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\begin{document}

\title{Seasonal and inter-seasonal RSV activity in the European Region during
the COVID-19 pandemic from Autumn 2020 to Summer 2022}



\author[1]{Margaux Meslé}%
\author[2]{Mary Sinnathamby}%
\author[1]{Piers Mook}%
\author[3]{the European Region Respiratory Network}%
\author[1]{Richard Pebody}%
\affil[1]{World Health Organization Regional Office for Europe}%
\affil[2]{UK Health Security Agency}%
\affil[3]{Affiliation not available}%


\vspace{-1em}



  
  \date{June 17, 2024}


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\selectlanguage{english}
\begin{abstract}
Background: The emergence of the Severe Acute Respiratory Syndrome
Coronavirus 2 (SARS-CoV-2) in early 2020 and subsequent implementation
of public health and social measures (PHSM) disrupted the epidemiology
of respiratory viruses. This work describes the epidemiology of RSV
observed during two winter seasons (weeks 40 to 20) and inter-seasonal
periods (weeks 21 to 39) during the pandemic between October 2020 and
September 2022. Methods: Using data submitted to The European
Surveillance System (TESSy) by countries or territories in the World
health Organization (WHO) European Region between weeks 40/2020 and
39/2022, we aggregated country-specific weekly RSV counts of sentinel,
non-sentinel and Severe Acute Respiratory Infection (SARI) surveillance
specimens and calculated percentage positivity. Results for both 2020/21
and 2021/22 seasons and inter-seasons were compared to pre-pandemic
2016/17 to 2019/20 seasons and inter-seasons. Results: Although more
specimens were tested than in pre-COVID-19 pandemic seasons, very few
RSV detections were reported during the 2020/21 season in all
surveillance systems. During the 2021 inter-season, a gradual increase
in detections was observed in all systems. In 2021/22, all systems saw
early peaks of RSV infection, and during the 2022 inter-seasonal period,
patterns of detections were closer to those seen before the COVID-19
pandemic. Conclusion: RSV surveillance continued throughout the COVID-19
pandemic, with an initial reduction in transmission, followed by very
high and out-of-season RSV circulation (summer 2021) and then an early
start of the 2021/22 season. RSV circulation during the 2022/23 season
had not yet normalised.%
\end{abstract}%



\sloppy


\emph{Title} : Seasonal and inter-seasonal RSV activity in the European
Region during the COVID-19 pandemic from Autumn 2020 to Summer 2022

\emph{Running title} : RSV in Europe during the COVID-19 pandemic period

\emph{Authors} : Margaux MI Mesl\selectlanguage{ngerman}é\textsuperscript{1}, Mary
Sinnathamby\textsuperscript{1}, Piers Mook\textsuperscript{1}, the WHO
European Region respiratory network group and Richard
Pebody\textsuperscript{1}

Corresponding author: Dr Richard Pebody (pebodyr@who.int)

\emph{Affiliations}\textbf{:}

\textsuperscript{1} World Health Organization (WHO) Regional Office for
Europe, Copenhagen, Denmark

\subsection*{Acknowledgements}

{\label{acknowledgements}}

We gratefully acknowledge the input and feedback from colleagues at the
European Center for Disease Prevention and Control (ECDC), namely Eeva K
Broberg, Edoardo Colzani and Phillip Zucs.

We express our gratitude to all ECDC staff involved in the RSV data
collection and the TESSy data management team, especially Marius
Valentin Valcu, for the technical support. We would also like to
acknowledge the physicians and nurses of sentinel network sites and
hospitals for their contribution in collecting specimens for RSV
testing. We also gratefully acknowledge the input of national clinical,
laboratory and public health staff involved in surveillance activities
and data submission to TESSy. The authors would also like to thank all
countries for the provision of data, including the following:

Belarus: Inna Karaban (Head of Department of Hygiene, Epidemiology and
Prevention, Ministry of Health, Minsk, Belarus).

Belgium: BELSARI-NET group consisting of Department of Infectiology, UZ
Brussel, Brussels (Lucie Seyler), Department of Infectious Diseases,
Centre hospitalier Universitaire Saint-Pierre, Brussels (Nicolas Dauby,
Benedicte Delaere, Marc Bourgeois), Department of Laboratory Medicine,
Medical Microbiology, Algemeen Ziekenhuis Sint-Jan, Brugge-Oostende AV
(Evelyn Petit, Marijke Reynders), Department of Microbiology and
Infection control, UZ Brussel, Brussels (Els Van Nedervelde, Thomas
Demuyser, Arne Witdouck, Siel Daelemans, Virgini Van Buggenhout,
Caroline Wylock), Department of Microbiology, Jessa Ziekenhuis, Hasselt
(Door Jouck, Koen Magerman, Marieke Bleyen), Epidemiology of Infectious
Diseases, Sciensano, Brussels (Melissa Vermeulen, Sebastien Fierens),
National Influenza Centre, Sciensano, Brussels (François Dufrasne, Sarah
Denayer, Cyril Barbezange), Pediatrics Department, CHU Saint-Pierre,
Université Libre de Bruxelles (ULB), Brussels (Marc Hainaut), Service of
Clinical Biology, Grand Hôpital de Charleroi, Charleroi (Benédicte
Lissoir) and Service of Infectiology, Grand Hôpital de Charleroi,
Charleroi (Xavier Holemans, Catherine Sion).

Czechia: Jan Kyncl, Alexander Nagy, Pavel Slezak, Jaromira Vecerova,
David Vostrak (all from the National Institute of Public Health, Prague,
Czech Republic).

Denmark: Members of the Danish National Influenza Team: Hanne-Dorthe
Emborg, Jens Nielsen, Lisbet Krause Knudsen, Lasse Skafte Vestergaard,
Amanda Bolt Botnen, Jesper Schak Krog.

Estonia: Irina Eero (Laboratory of~ Infectious Diseases), Liisa Lilje
(Laboratory of~ Infectious Diseases) ~and Eliisa Metsoja (Estonian
Health Board Influenza Centre, chief specialist).

France: Bruno Lina, Martine Valette, Sylvie van der Werf, Thierry
Blanchon, Nael Zemali, Sylvie Behillil, Delphine Viriot.

Ireland: Joan O'Donnell, Jeff Connell, Irish sentinel GP network, ICGP,
NVRL, SARI surveillance team and HPSC influenza team.

The Netherlands: We thank the Dutch Working Group on Clinical Virology
(NWKV) from the Dutch Society for Clinical Microbiology (NVMM) and all
participating laboratories for providing the virological data from the
weekly laboratory virological report (non-sentinel data). We thank
Anne-Marie van den Brandt, Bas van der Veer, Lynn Aarts and Hai Xi
Wiegmans, representing the wider team of technicians participating in
RSV molecular diagnostics. We thank Rianne van Gageldonk-Lafeber, Marit
de Lange, Daphne Reukers and Liz Jenniskens, from the RIVM EPI
respiratory surveillance team. We thank Mariette Hooiveld from Nivel,
the GP's participating in the Nivel sentinel surveillance network and
their patients for participating in the respiratory surveillance.

Portugal: Portuguese GP Sentinel Network, Portuguese Laboratory Network
for Influenza and other Respiratory Viruses Diagnosis; Ana Rita Torres
(Department of Epidemiology, National Institute of Health Doctor Ricardo
Jorge); Aryse Melo, Camila Henriques, Inês Costa, Licínia Gomes, Miguel
Lança, Nuno Verdasca (National Reference Laboratory for Influenza and
Other Respiratory Viruses, Infectious Diseases Department, National
Institute of Health Doctor Ricardo Jorge).

Spain: Concepción Delgado-Sanz, Clara Mazagatos, Susana Monge (National
Center of Epidemiology, CIBERESP; Carlos III Health Institute);
Inmaculada Casas (National Center of Microbiology, CIBERESP; Carlos III
Health Institute); Tomás Vega (Servicio de Información de Salud Pública,
DGSP, Consejería de Sanidad, Castilla y León).

Sweden: AnnaSara Carnahan (Folkhälsomyndigheten, Solna).

Switzerland: Swiss Sentinel Network and the Federal Office of Public
Health.

United Kingdom (Wales): Jana Zitha, Panoraia Kalapotharakou, Anastasia
Couzens, Kathleen Pheasant and Laura Gifford (Public Health Wales
Virology and ARI surveillance team).

Uzbekistan: Dr Bakhodir Yusupaliyev, (Head of the Sanitary and
Epidemiological Welfare and Public Health Service of the Republic of
Uzbekistan) and Dr Sultan Djemileva, (Head of the Virological Laboratory
of the Sanitary and Epidemiological Welfare and Public Health Service of
the Republic of Uzbekistan).

Kosovo11This designation is without prejudice to positions on status,
and is in line with UNSCR 1244 and the ICJ Opinion on the Kosovo
Declaration of Independence. All references to Kosovo in this document
should be understood to be in the context of the United Nations Security
Council resolution 1244 (1999).: Zana Deva (National Institute of Public
Health of Kosovo) and Pranvera Kacaniku (National Institute of Public
Health of Kosovo).

\subsection*{Funding information:}

{\label{funding-information}}

The WHO Regional Office for Europe was supported for work on influenza
and other respiratory viruses by a cooperative agreement from the United
States Centers for Disease Control and Prevention (NU51IP000936); the
funder had no role in the analysis or interpretation of the data.

\subsection*{Conflict of interest:}

{\label{conflict-of-interest}}

The following authors declare having received funding from the
innovative medicines initiative (IMI): Adam Meijer (The Netherlands),
Anne Teirlinck (The Netherlands). All other authors have no conflicts of
interest to declare.

\emph{Disclaimer} :

The author affiliated with the World Health Organization (WHO) is alone
responsible for the views expressed in this publication and they do not
necessarily represent the decisions or policies of the WHO.

\section*{Abstract:}

{\label{abstract}}

\emph{Background} : The emergence of the Severe Acute Respiratory
Syndrome Coronavirus 2 (SARS-CoV-2) in early 2020 and subsequent
implementation of public health and social measures (PHSM) disrupted the
epidemiology of respiratory viruses. This work describes the
epidemiology of RSV observed during two winter seasons (weeks 40 to 20)
and inter-seasonal periods (weeks 21 to 39) during the pandemic between
October 2020 and September 2022.

\emph{Methods} : Using data submitted to The European Surveillance
System (TESSy) by countries or territories in the World health
Organization (WHO) European Region between weeks 40/2020 and 39/2022, we
aggregated country-specific weekly RSV counts of sentinel, non-sentinel
and Severe Acute Respiratory Infection (SARI) surveillance specimens and
calculated percentage positivity. Results for both 2020/21 and 2021/22
seasons and inter-seasons were compared to pre-pandemic 2016/17 to
2019/20 seasons and inter-seasons.

\emph{Results} : Although more specimens were tested than in
pre-COVID-19 pandemic seasons, very few RSV detections were reported
during the 2020/21 season in all surveillance systems. During the 2021
inter-season, a gradual increase in detections was observed in all
systems. In 2021/22, all systems saw early peaks of RSV infection, and
during the 2022 inter-seasonal period, patterns of detections were
closer to those seen before the COVID-19 pandemic.

\emph{Conclusion} : RSV surveillance continued throughout the COVID-19
pandemic, with an initial reduction in transmission, followed by very
high and out-of-season RSV circulation (summer 2021) and then an early
start of the 2021/22 season. RSV circulation during the 2022/23 season
had not yet normalised.

\subsection*{Key words:}

{\label{key-words}}

Respiratory Syncytial Virus; sentinel; non-sentinel; severity;
surveillance; epidemiology; Europe; COVID-19 pandemic

\section*{Main text}

{\label{main-text}}

\subsection*{Introduction}

{\label{introduction}}

In temperate regions, respiratory syncytial virus (RSV) typically
circulates in the winter months, causing more severe illness
particularly in infants and older adults which often results in
hospitalisation, including admission to intensive care
units\textsuperscript{1,2}. There are often periods of co-circulation
with influenza and other seasonal respiratory viruses. RSV is monitored
through sentinel and/or non-sentinel surveillance in many countries,
territories and areas (henceforth referred to as countries) in the World
Health Organization (WHO) European Region, the European Union (EU) and
European Economic Area (EEA) countries (hereafter referred to as
Europe). These sentinel surveillance systems were originally established
for influenza and previously described \textsuperscript{3}. A number of
RSV vaccines are approaching possible licensure \textsuperscript{4--6}.
Monoclonal immunoglobulins are available as prophylaxis during the
typical period of RSV circulation to protect young infants with chronic
underlying heart and lung disease at higher risk of severe
disease\textsuperscript{7}.

The emergence and spread of Severe Acute Respiratory Syndrome
Coronavirus 2 (SARS-CoV-2) in early 2020 and the subsequent public
health and social measures (PHSM) implemented by Member states to reduce
its transmission and anticipated morbidity and mortality have disrupted
the spread of other respiratory viruses, including RSV, in both the
southern \textsuperscript{5,8,9} and northern
hemispheres\textsuperscript{10--12}.

This work aims to describe the epidemiology of RSV in Europe during the
2020/21 and 2021/22 winter seasons (weeks 40/2020 to 20/2021 and 40/2021
to 20/2022) and two inter-seasonal periods (weeks 21 to 39/2021 and 21
to 39/2022) through three surveillance systems (primary care sentinel,
secondary care Severe Acute Respiratory Infection (SARI), and
non-sentinel surveillance) in comparison to historical pre-COVID-19
pandemic data.

\subsection*{Methods}

{\label{methods}}

This retrospective epidemiological analysis of RSV used weekly data
submitted to The European Surveillance System (TESSy) by the European
Regional surveillance network jointly coordinated by ECDC and the WHO
Regional Office for Europe. As RSV is not notifiable, reporting is
voluntary. Weekly counts of detections and specimens tested in 48
reporting countries between week 40/2020 and week 39/2022 were
downloaded on 14\textsuperscript{th} October 2022. Countries were
included in this analysis if at least one sample tested was reported.

Using specimens taken from selected cases of influenza-like illness
(ILI) and acute respiratory infection (ARI) presenting toe primary care
sentinel surveillance system (these systems have been described
previously \textsuperscript{3}, we calculated the aggregated weekly
counts of RSV detections and tests and the percentage positivity when at
least ten tests were performed. These counts and percentages were
compared to the four previous seasons (2016/17 to 2019/20; hereafter
referred to as pre-COVID-19 pandemic seasons). Using weekly RSV
percentage positivity from four pre-COVID-19 pandemic seasons of
sentinel data, we used the Moving Epidemic Method (MEM) to calculate
RSV-specific epidemic thresholds for each country (Supplementary table
2) and identify potential changes in seasonal patterns, as previously
shown \textsuperscript{13}. It is important to note that these
thresholds may differ from those used in country for surveillance
purposes. Epidemic activity was determined to have started when
percentage positivity was above the country-specific epidemic threshold
for the first of at least two consecutive weeks. The duration of the
epidemic period was defined as the total number of weeks above the
threshold (including non-consecutive weeks).

Similarly, aggregated weekly counts of detections and specimens tested
were calculated, along with percentage positivity, for SARI sentinel
surveillance (hospital inpatients meeting the case definition). Only two
countries reported data in 2020/21 and sixteen in 2021/22al periods;
historical data regarding number of tests performed were unavailable for
this surveillance system. Data included aggregated SARI cases by age
group (\selectlanguage{english}[?]4 years, 5 to 14 years, 15 to 64 years and \selectlanguage{english}[?]65 years).

For the non-sentinel surveillance system, only the weekly counts of
detections were aggregated but percentage positivity could not always be
calculated given the unavailability and/or uncertainty around some of
the denominators. Specimens from this system were taken from patients
that originated from hospitals, schools, primary care facilities not
involved in sentinel surveillance, or nursing homes and other
institutions.

For all three systems, data in the study period were compared to
historical data. Some countries stopped surveillance or reporting data
to TESSy over the summer months for some surveillance systems
considered. All analyses were conducted in R version
4.0.5\textsuperscript{14}.

\subsection*{Results}

{\label{results}}

Primary care sentinel surveillance

When compared to pre-COVID-19 pandemic seasons, there was an increase in
the number of specimens tested for RSV in both the 2020/21 and the
2021/22 season: 21,803 and 36,040, respectively, compared to an annual
average of 15,796 in pre-COVID-19 pandemic seasons (from 21 countries on
average), representing a 38\% and 128\% increase, respectively. More
countries reported during the 2021/22 season than during the 2020/21 and
pre-COVID-19 pandemic seasons (Figure 1A, B, Table 1).

A total of 19 countries reported only 195 RSV detections from a total of
21,803 primary care sentinel surveillance specimens tested during the
2020/21 seasonal period. This represents an overall positivity of 1\%,
ranging up to 7\% in France, which was lower than in the four
pre-COVID-19 pandemic seasons (mean of 1,669 positive specimens, 11\%
positivity from an average of 21 countries) (Figure 1A, B, Table 1).
Only seven countries reported at least five detections during the
2020/21 season (Supplementary table 1). Only France and Switzerland saw
clear waves of activity. Between weeks 5/2020 and 19/2021 in France,
percentage positivity was above 10\% for all but two weeks, whereas
Switzerland saw percentage positivity between 4\% and 17\% between weeks
16 and 20/2021 (Supplementary table 1).

During the 2020/21 season, of the nine countries where the epidemic
thresholds could be calculated, only France reported peaks of RSV
positivity above its threshold. France, Germany and Slovenia experienced
early starts to their 2021/22 seasonal period compared to the average
starting week of pre-COVID-19 pandemic seasons (Figure 2).

During the 2021 inter-seasonal period, a total of 316 positive specimens
from 5,076 specimens tested (6\% positivity) were reported from 17
countries (Figure 1A, B and Table 1). A total of nine countries (Estonia
(n=8, 5\% positivity), France (n=5, 4\%), Georgia (n=21, 3\%), Germany
(n=175, 7\%), Ireland (n=7, 2\%), the Netherlands (n=39, 22\%), Slovenia
(n=16, 16\%), Switzerland (n=35, 9\%) and Ukraine (n=5, 4\%)) saw higher
than usual activity (Supplementary Figure 1). Of the countries with
inter-seasonal activity, three (Germany, the Netherlands and Slovenia)
exceeded their MEM epidemic threshold, with only the Netherlands having
experienced activity during this inter-seasonal time period in
pre-COVID-19 pandemic seasons. This represents only sporadic detections,
as numbers of collected samples are generally low in the inter-seasonal
time period (Figure 2, Supplementary Figure 1).

During the 2021/22 season, 34 countries reported 2,018detections from
36,040 tests performed (6\% positivity). This was higher than during the
2020/21 season, but lower than during the pre-COVID-19 pandemic seasons
(Figure 1A, B, Table 1). A peak of 17\% positivity was observed in week
40/2021 which then fell to 3\% (week 2/2022) and remained below this
level until the end of the season. Regionally, this peak was higher than
in the pre-COVID-19 pandemic season when regional positivity did not
rise above 5\% for any given week (Figure 1B, Table 1). In six countries
(Denmark, Slovenia, Sweden, United Kingdom (Northern Ireland, Scotland
and Wales)), the start of the 2021/22 season was already discernible in
the latter part of the 2021 inter-seasonal period with detections
peaking before or after week 40/2021. Where possible to compare with
pre-COVID-19 pandemic seasons (n=23 countries), 14 countries experienced
similar or higher positivity. Positive specimens continued to be
detected in several countries during the second half of the season
leading into the 2022 inter-seasonal period, most notably in Georgia,
the Netherlands, Spain and Switzerland (Supplementary Figure 1B).

During the 2022 inter-seasonal period, 375 detections were reported from
19,197 samples tested (2\% positivity) from 27 countries. Both the
number of tests performed and positivity for this period were higher
than seen in pre-COVID-19 pandemic inter-seasons: up to 1,336 tests and
up to 1\% positivity (Table 1). Eight countries reported RSV activity
outside of the characteristic winter season with at least five
detections: Denmark (n=59, 3\% positivity), Georgia (n=33, 5\%), Germany
(n=15, 1\%), the Netherlands (n=40, 6\%), Spain (n=103, 1\%),
Switzerland (n=9, 1\%), United Kingdom (Scotland) (n=86, 9\%) and
Slovenia (n=12, 15\%) (Supplementary Figure 1, Supplementary table 1).
During this period, only the Netherlands and United Kingdom (Scotland)
experienced RSV positivity reaching the epidemic levels previously
calculated (Figure 2).

Non-sentinel surveillance

A total of 18 countries reported at least one non-sentinel RSV detection
in the 2020/21 season, with a total of 6,966 detections. This compares
to an average of 49,738 detections from 32 countries in pre-COVID-19
pandemic seasons (Figure 1C, Table 1). Between weeks 40/2020 and 1/2021,
fewer than 60 weekly detections were recorded, much less than the weekly
average during the pre-COVID-19 pandemic seasons for the same weeks: 180
(week 40) to 3,437 (week 1). Detections peaked in week 12/2021 (Iceland
and Ukraine) with 722 RSV detections and fell thereafter until week
18/2021. Between weeks 12 and 18/2021, the number of detections was
comparable to pre-COVID-19 pandemic seasons (Figure 1C). For the
countries with at least one historical season for comparison (n=17),
only Iceland and Ukraine experienced more detections (Supplementary
table 2) and Finland, Greece, Hungary, Poland, Portugal, Republic of
Moldova, Serbia, and the United Kingdom saw an earlier peak in 2020/21
than in pre-COVID-19 pandemic seasons.

The 2021 inter-season saw 18,325 RSV detections reported from 20
countries, all of which could be compared to pre-COVID-19 pandemic
seasons and mostly had higher numbers in 2021 in comparable weeks
(average of 220 detections from 13 countries), with the exceptions of
Estonia and Latvia (Figure 1C, Table 1, Supplementary table 2). This
period was characterised by a gradual rise in detections (peaking in
week 39/2021 with 2,646 detections) which had previously not been
reported.

During the 2021/22 season, 62,426 detections were reported from 34
countries, of which 32 could be compared to pre-COVID-19 pandemic
seasons (Figure 1, Table 1). The start of the 2021/22 season was a
continuation of the high levels of detections already seen during the
2021 inter-seasonal period, with two peaks of detections: weeks 40/2021
(observed in Denmark, Slovenia, United Kingdom (Northern Ireland,
Scotland, Wales) and 46/2021 (observed in France and Spain). From week
48/2021 until week 7/2022, the numbers of positive detections then
gradually fell to levels lower than in pre-COVID-19 pandemic seasons.
Between weeks 17 and 20/2022, the weekly average of detections was 514,
higher than any pre-COVID-19 pandemic season (Figure 1C). Of the
countries with historical comparisons, nine recorded fewer, 10 recorded
more and 13 recorded a similar number of detections than in pre-COVID-19
pandemic seasons (Supplementary table 2).

Most countries recorded unusually high and/or early peaks of activity
during the 2021/22 season. Some countries (Iceland, the Netherlands) saw
a biphasic seasonal activity. Others, (Denmark, Portugal, Russian
Federation, Slovenia, United Kingdom (England, Scotland and Wales)) saw
their number of detections decline after an early peak but then rise
into the 2022 inter-seasonal period Supplementary table 2).

The 2022 inter-season saw 8,876 RSV detections from 24 countries, of
which 18 had historical data for comparison (Figure 1C, Table 1,
Supplementary table 2). Bulgaria, Iceland, Portugal, Russian Federation
and United Kingdom (Northern Ireland and Scotland) observed more
detections than during pre-COVID-19 pandemic inter-seasons but without a
distinct peak of activity (Supplementary figure 2). In contrast, the
Netherlands and United Kingdom (Wales) did experience a peak of
detections in weeks 23/2022 and 28/2022, respectively. Denmark, France,
Slovenia and Spain reported a rise in activity late in the period and
leading into the 2022/23 season (Supplementary figure 2).

SARI surveillance

During the 2020/21 season, only Belgium and Malta reported SARI data,
but only Belgium reported 144 cases identified among 682 patients tested
(21\% positivity). This compares to an average of 200 detections from 7
countries in pre-COVID-19 pandemic seasons (Table 1). Detections peaked
in week 20/2021 with 55\% positivity (n=17) (Figure 1D, E). Of the 480
patients with known age (all from Belgium), 136 tested positive (28\%
positivity), with children \selectlanguage{english}[?]4 years representing 90\% of patients (41\%
positivity). Children aged 5 to 14 years saw 26\% positivity which was
higher than in the oldest age group (7\%) (Table 2).

During the 2021 inter-season, seven countries (Armenia, Belgium,
Georgia, Ireland, Malta, Russian Federation and Ukraine) reported SARI
data with a total of 148 RSV detections from 1,983 patients (7\%
positivity). This compares to up to 15 detections from up to three
countries in pre-COVID-19 pandemic seasons (Table 1, Supplementary Table
1). Between weeks 24 and 37/2021, the percentage positivity ranged
between 2\% and 9\%, except for week 30/2021 when no detections were
reported. Percentage positivity peaked in week 39/2021 at 10\%, leading
into the 2021/22 season (Figure 1E, supplementary Figure 3). When
possible to compare with sentinel systems (Georgia, Ireland, Russian
Federation and Ukraine), all countries but Ireland saw a delayed peak in
SARI positivity after the one in sentinel detections. Among 898 patients
with known age tested in five countries, 89 (10\%) were positive.
Children \selectlanguage{english}[?]4 years accounted for 81\% (n=72) of all cases with known age,
and 18\% of their samples tested positive for RSV. Only Belgium reported
over 10\% positivity in another age group (those \selectlanguage{english}[?]65 years) (Figure 3,
Table 2).

During the 2021/22 season, 948 SARI cases were reported among 9,478
patients tested (10\% positivity) in 16 countries (Figure 1 D, E, Table
1). A peak of 25\% positivity was observed in week 47/2021 in Georgia
and Turkiye, after which it fell until week 3/2022 and mostly ranged
between 1\% and 5\% until the end of the season (Figure 1E). Among 5,220
patients with known age, 569 detections (11\%) were reported by 12
countries. These included 506 (89\%) in children \selectlanguage{english}[?]4 years and 13 (2\%)
in persons \selectlanguage{english}[?]65 years with a percentage positivity of 20\% and 1\%,
respectively (Table 2). Positive specimens in the youngest age group
peaked at the start of the season and in week 18/2022 (Figure 3).

During the 2022 inter-season, 136 RSV detections were reported from
4,238 patients tested (3\% positivity) in 11 countries, with positivity
ranging between 1\% and 6\% and peaking in week 24/2022 (Table 1, Figure
1E, Supplementary Table 1, Supplementary figure 3). Of the 32 cases
reported with known age, 29 were \selectlanguage{english}[?] 4 years from 6 countries (4\%
positivity) (Table 2).

\subsection*{Discussion}

{\label{discussion}}

We showed that the COVID-19 pandemic and its response has impacted the
circulation of RSV in Europe since the Autumn of 2020. Very little
circulation was seen during the 2020/21 season, but unusual
inter-seasonal activity was seen in summer 2021, followed by early and
high peaks of activity during the 2021/22 season as observed in all
surveillance systems. This atypical inter-seasonal activity continued in
many countries in the summer months of 2022. Hospitalised cases of RSV
have been predominantly in those aged \selectlanguage{english}[?]4 years.

Although countries included in this analysis have tested more specimens
from sentinel surveillance systems for RSV during the COVID-19 pandemic
than in prior seasons, fewer viruses were detected during the usual
weeks of RSV circulation of the 2020/21 season. The similar findings
from three separate surveillance systems (primary care sentinel,
non-sentinel and SARI) and a higher number of countries reporting
compared to pre-COVID-19 pandemic seasons provide some assurance that
this is a true observation of reduced circulation of RSV, likely due to
the impact of public health and social measures in the early phase of
the pandemic rather than a change in testing practices.

Many countries also observed an unusual increase in RSV activity in the
summer months of 2021 and 2022, representing out-of-season activity, in
all systems, usually translating into an early start of the next
epidemic season. In primary care sites in some countries (Denmark,
Germany and Slovenia, among others), the 2021/22 season began earlier
than during pre-COVID-19-pandemic seasons. In other parts of the Region
(such as in France, Ireland and the Netherlands among others),
seasonality returned to similar timing to those observed in
pre-COVID-19-pandemic seasons, but with much higher positivity. Both
observations may be associated with the lack of RSV circulation observed
during the 2020/21 season and hence a widespread lack of exposure to
RSV, particularly in younger cohorts, resulting in the build-up of an
increased pool of susceptibles.

When comparing SARI activity to historical data, a higher peak of
detections was seen late in the 2020/21 season and early during the
2021/22 season. Due to a lack of historical denominator data, it was not
possible to compare the patterns of positivity. Children aged \selectlanguage{english}[?]4 years
were disproportionately more affected than any other age group,
accounting for at least 89\% of all SARI cases during all four periods
considered whereas those aged \selectlanguage{english}[?]65 years accounted for 2\% of cases,
fewer than would be expected \textsuperscript{15}. This may be a result
of PHSM against COVID-19 and continued behavioural changes, especially
in older generations, such as continued social distancing or mask
wearing even after measures have been lifted. However, it may also be
explained by some countries (in eastern Europe and Central Asia) having
a lower threshold for hospitalising young children than other age
groups\textsuperscript{3} or changing their testing practices during the
COVID-19 pandemic.

Previous studies have looked at the importance of RSV infection causing
hospitalisation in the first two years of life \textsuperscript{7,16}.
Given that children born during the COVID-19 pandemic are unlikely to
have been exposed to RSV in their first or second year of life, it is
possible that when they are older, the severity of a primary RSV
infection is reduced. However, it is also possible that the number of
children hospitalised during the 2022/23 season will still be greater
due to the large number of RSV-naive children born since the start of
the pandemic, resulting in a high burden of disease and hospitalisation
rate \textsuperscript{5}. Combined with hospitalisations resulting from
other respiratory viruses across all age groups, RSV has the potential
to cause high pressure on healthcare systems across the
Region\textsuperscript{8}.

This significant shift in circulation patterns was also observed in
other parts of the world where RSV typically also circulates during the
winter months such as in Australia and New Zealand\textsuperscript{5,10}
or South Africa \textsuperscript{5,8,10,17}. RSV circulation was not
uniform across these countries, with some experiencing stronger than
expected out-of-season activity\textsuperscript{8}, while others
experienced delayed or continued circulation \textsuperscript{5}. A
delayed circulation of RSV during the summer months had previously been
reported after the 2009 A(H1N1) influenza pandemic \textsuperscript{18}.
The overall reduction in transmission was a very possible result of PHSM
implemented (such as mask wearing, stay-at-home orders and school
orders) to restrict the spread of SARS-CoV-2 within and between
countries \textsuperscript{9} by breaking transmission chains. We know
this implementation was neither uniform between countries nor over time
and may be an important factor; similar results were found by other
groups \textsuperscript{19}.

This analysis contains several limitations, including the limited and
varying number of countries that report data through various
surveillance systems, some of which are not an integral part of routine
surveillance but have been part of ECDC projects initiated during the
COVID-19 pandemic. Changes in testing practices and number of reporting
sites because of the COVID-19-pandemic were not considered here. The MEM
thresholds were based on only four historical seasons, and very few
countries could be included due to the intermittent absence of weekly
data or denominators. The interpretation of the calculated epidemic
thresholds should therefore be taken with caution, and do not
necessarily represent the national epidemic threshold that are set by
the individual countries. There were too few countries for a robust
investigation into geo-temporal patterns of increased activity across
countries in the Region. The lack non-sentinel denominator data did not
allow systematic percentage positivity calculations, a potential
weakness of this data source when interpreted alone. However, the
consistency of non-sentinel trends with those from other surveillance
systems provides some reassurance to the validity of the results.
Additionally, the availability of age data for sentinel, non-sentinel
and historical SARI surveillance systems would have allowed a better
understanding of which age groups have been most affected by these
unusual circulation patterns and whether children were overrepresented.
Finally, the limited number of countries reporting SARI age data may not
be representative of the Region (also given that these countries are
mostly located in its Eastern part) or of the age distribution of
patients at large (it is unclear if cases have an a priori equal chance
of being tested for RSV regardless of their age). Unfortunately, the
absence of historical SARI denominator data and the large age groups
into which cases are grouped do not allow for more detailed
interpretation of our results. In addition, during the COVID-19 pandemic
there was varying degrees of disruption to national sentinel
surveillance systems due to changes in health seeking behaviours and
limitations in the capacity of sites to receive cases and take
specimens, impacting the ability of these systems to monitor respiratory
viruses, including RSV.

Despite these limitations, this descriptive study illustrates how the
emergence of a novel respiratory virus and associated public health
measures can significantly disrupt the circulation of established
seasonal respiratory viruses. It is likely that absence of circulation
of seasonal respiratory pathogens during a season led to out-of-season
activity, and potentially, to larger than expected peaks of activity
thereafter, as observed in summer 2021 and the early 2021/22 season. RSV
activity during the 2022/23 season continues to follow unusual patterns
and the implementation of integrated surveillance systems monitoring
multiple respiratory viruses simultaneously may prove invaluable to both
monitor RSV and other seasonal viral respiratory infections, but also in
planning for the future emergence of a novel pandemic respiratory virus.

\subsection*{Conclusion}

{\label{conclusion}}

The emergence and spread of SARS-CoV-2 and associated control measures
in the EU/EEA and in the WHO European Region have significantly impacted
the spread and timing of seasonal respiratory viruses such as RSV. For
the last two winter seasons, and for the summer periods in between, much
higher proportions of RSV detections or a temporal shift in
transmissions were detected compared to pre-COVID-19 pandemic seasons.
Further work is required to determine the possible explanatory factors
including the implementation and relaxation in PHSM and factors such as
possible SARS-CoV-2 viral interference to this shift in timing, activity
and potential difference in age distribution of RSV cases. These results
highlight the importance of being aware of and preparing for continued
potential unusual patterns in the epidemiology of RSV (and other
respiratory viruses). It is also a lesson learnt with regard to the
impact of future emergence and spread of respiratory viruses with
pandemic potential on the epidemiology of seasonal respiratory viruses.

\emph{Addendum} :

The WHO European Region respiratory network group authorship consists
of:

Anissa Lakhani\textsuperscript{2}, Maria Zambon\textsuperscript{2},
Odette Popovici\textsuperscript{3}, Mihaela Laz\selectlanguage{polish}ă\selectlanguage{english}r\textsuperscript{4},
Amela Dedei\selectlanguage{polish}ć \selectlanguage{english}Ljubovi\selectlanguage{polish}ć\selectlanguage{english}\textsuperscript{5}, Nina Rodi\selectlanguage{polish}ć
\selectlanguage{english}Vukmir\textsuperscript{6, 7}, Ay\selectlanguage{polish}ş\selectlanguage{english}e Ba\selectlanguage{polish}ş\selectlanguage{english}ak Alta\selectlanguage{polish}ş\selectlanguage{english}\textsuperscript{8}, Emine
Avci\textsuperscript{8}, Katarzyna \selectlanguage{polish}Ł\selectlanguage{english}uniewska\textsuperscript{9}, Karol
Szyma\selectlanguage{polish}ń\selectlanguage{english}ski\textsuperscript{9}, Greta Gargasiene\textsuperscript{10},
Svajune Muralyte\textsuperscript{11}, Ausra
Dziugyte\textsuperscript{12}, Graziella Zahra\textsuperscript{12}, Ana
Rita Gon\selectlanguage{ngerman}çalves\textsuperscript{13}, Tania
Spedaliero\textsuperscript{13}, Guillaume Fournier\textsuperscript{14},
Daniel Alvarez-Vaca\textsuperscript{14}, Goranka
Petrovi\selectlanguage{polish}ć\selectlanguage{english}\textsuperscript{15}, Irena Tabain\textsuperscript{15}, Katarina
Prosenc\textsuperscript{16}, Maja Socan\textsuperscript{17}, Jelena
Protic\textsuperscript{18}, Dragana Dimitrijevic\textsuperscript{19},
Alina Druc\textsuperscript{20}, Mariana Apostol\textsuperscript{20},
Kate Karolina Kalasnikova\textsuperscript{21}, Sergejs
Nikisins\textsuperscript{22}, Janine Reiche\textsuperscript{23}, Wei
Cai\textsuperscript{23}, Adam Meijer\textsuperscript{24}, Anne
Teirlinck\textsuperscript{24}, Amparo Larrauri\textsuperscript{25},
Inmaculada Casas\textsuperscript{25}, Vincent Enouf\textsuperscript{26},
Sophie Vaux\textsuperscript{27}, Frederikke Kristensen
Lomholt\textsuperscript{28}, Ramona Trebbien\textsuperscript{28}, Helena
Jirincova\textsuperscript{29}, Helena Sebestova\textsuperscript{29},
M\selectlanguage{ngerman}ónika Rózsa\textsuperscript{30}, Zsuzsanna Molnár\textsuperscript{30},
Gudrun Aspelund\textsuperscript{31}, Gudrun Erna
Baldvinsdottir\textsuperscript{32}, Simon Cottrell\textsuperscript{33},
Catherine Moore\textsuperscript{33}, Athanasios
Kossyvakis\textsuperscript{34}, Kassiani Mellou\textsuperscript{35},
Olga Sadikova\textsuperscript{36}, Johanna Kristina
Tamm\textsuperscript{36}, Nathalie Bossuyt\textsuperscript{37}, Isabelle
Thomas\textsuperscript{37}, Edita Staro\selectlanguage{polish}ň\selectlanguage{english}ov\selectlanguage{ngerman}á\textsuperscript{38},
Lyudmila Kudasheva\textsuperscript{39}, Boris
Pleshkov\textsuperscript{39}, Niina Ikonen\textsuperscript{40}, Otto
Helve\textsuperscript{40}, Emma Dickson\textsuperscript{41}, Tanya
Curran\textsuperscript{42}, Kseniya Komissarova\textsuperscript{43},
Kirill Stolyarov\textsuperscript{43}, Veronika
Vysotskaya\textsuperscript{44}, Natallia Shmialiova\textsuperscript{45},
Bo\selectlanguage{polish}ž\selectlanguage{english}idarka Rako\selectlanguage{polish}č\selectlanguage{english}evi\selectlanguage{polish}ć\selectlanguage{english}\textsuperscript{46}, Danijela
Vujo\selectlanguage{polish}š\selectlanguage{english}evi\selectlanguage{polish}ć\selectlanguage{english}\textsuperscript{46}, Romella Abovyan\textsuperscript{47},
Shushan Sargsyan\textsuperscript{47}, Khatuna
Zakhashvili\textsuperscript{48}, Ann Machablishvili\textsuperscript{48},
Oksana Koshalko\textsuperscript{49}, Iryna
Demchyshyna\textsuperscript{49}, Michal Mandelboim\textsuperscript{50},
Aharona Glatman-Freedman\textsuperscript{50}, Rory
Gunson\textsuperscript{51}, Shivani Karanwal\textsuperscript{52}, Raquel
Guiomar\textsuperscript{53}, Ana Paula Rodrigues\textsuperscript{54},
Charlene Bennett\textsuperscript{54}, Lisa Domegan\textsuperscript{55},
Arijana Kalaveshi\textsuperscript{56}, Xhevat
Jakupi\textsuperscript{56}, Gurbangul Ovliyakulova\textsuperscript{57},
Neli Korsun\textsuperscript{58}, Nadezhda
Vladimirova\textsuperscript{58}

\emph{Affiliations}\textbf{:}

\textsuperscript{2} UK Health Security Agency, London, England, United
Kingdom (UK)

\textsuperscript{3} National Institute of Public Health, Bucharest,
Romania

\textsuperscript{4} Cantacuzino National Military-Medical Institute for
Research and Development, Bucharest, Romania

\textsuperscript{5} Clinical Center University of Sarajevo, Sarajevo,
Bosnia and Herzegovina

\textsuperscript{6} Public Health Institute of the Republic of Srpska,
Banja Luka, Bosnia and Herzegovina

\textsuperscript{7} Faculty of Medicine University of Banja Luka, Banja
Luka, Bosnia and Herzegovina

\textsuperscript{8} General Directorate of Public Health, Ankara,
T\selectlanguage{ngerman}ürkiye

\textsuperscript{9} National Research Institute, Warsaw, Poland

\textsuperscript{10} National Public Health Center under the Ministry of
Health, Vilnius, Lithuania

\textsuperscript{11} National Public Health Surveillance Laboratory,
Vilnius, Lithuania

\textsuperscript{12} Ministry for Health Regulation, Pieta, Malta

\textsuperscript{13} University of Geneva Hospitals, Geneva, Switzerland

\textsuperscript{14} Laboratoire national de santé, Dudelange,
Luxembourg

\textsuperscript{15} Croatian Institute of Public Health, Zagreb,
Croatia

\textsuperscript{16} National Laboratory of Health, Environment and
Food, Ljubljana, Slovenia

\textsuperscript{17} National Institute of Public Health, Ljubljana,
Slovenia

\textsuperscript{18} Institute of Virology, Vaccines and Sera Torlak,
Belgrade, Serbia

\textsuperscript{19} Institute of Public Health of Serbia, Belgrade,
Serbia

\textsuperscript{20} National Agency for Public Health, Chi\selectlanguage{polish}ş\selectlanguage{english}in\selectlanguage{polish}ă\selectlanguage{english}u,
Republic of Moldova

\textsuperscript{21} Centre for Disease Prevention and Control, Riga,
Latvia

\textsuperscript{22} Riga East university hospital, Riga, Latvia

\textsuperscript{23} Robert Koch Institute, Berlin, Germany

\textsuperscript{24} Centre for Infectious Disease Control, Bilthoven,
The Netherlands

\textsuperscript{25} Carlos III Health Institute, Madrid, Spain

\textsuperscript{26} Institut Pasteur, Paris, France

\textsuperscript{27} Sant\selectlanguage{ngerman}é Publique France, Saint Maurice, France

\textsuperscript{28} Statens Serum Institute, Copenhagen, Denmark

\textsuperscript{29} National Institute of Public Health, Prague,
Czechia

\textsuperscript{30} National Public Health Center, Budapest, Hungary

\textsuperscript{31} The Directorate of Health, Reykjavik, Iceland

\textsuperscript{32} The National University Hospital of Iceland,
Reykjavik, Iceland

\textsuperscript{33} Public Health Wales, Cardiff, Wales, United Kingdom

\textsuperscript{34} Hellenic Pasteur Institute, Athens, Greece

\textsuperscript{35} National Public Health Organization, Athens, Greece

\textsuperscript{36} The Estonian Health Board, Tallinn, Estonia

\textsuperscript{37} Sciensano, Brussels, Belgium

\textsuperscript{38} Public Health Authority of the Slovak Republic,
Bratislava, Slovakia

\textsuperscript{39} Sanitary and Epidemiological Welfare and Public
Health Service of the Republic of Uzbekistan, Toshkent, Uzbekistan

\textsuperscript{40} Finnish Institute for Health and Welfare, Helsinki,
Finland

\textsuperscript{41} Public Health Agency, Belfast, Northern Ireland,
United Kingdom

\textsuperscript{42} Belfast Health and Social Care Trust, Belfast,
Northern Ireland, United Kingdom

\textsuperscript{43} Smorodintsev Research Institute of Influenza, St
Petersburg, Russian Federation

\textsuperscript{44} Republican Center for Hygiene, Epidemiology and
Public Health, Minsk, Belarus

\textsuperscript{45} Republican Research and Practical Center for
Epidemiology and Microbiology, Minsk, Belarus

\textsuperscript{46} Institute of Public Health of Montenegro,
Podgorica, Montenegro

\textsuperscript{47} National Center for disease control and prevention,
Yerevan, Armenia

\textsuperscript{48} National Center for Disease Control and Public
Health, Tbilisi, Georgia

\textsuperscript{49} Public Health Center of the Ministry of Health of
Ukraine, Kyiv, Ukraine

\textsuperscript{50} Israel Ministry of Health, Ramat Gan, Israel

\textsuperscript{51} West of Scotland Specialist Virology Centre,
Glasgow, Scotland, United Kingdom

\textsuperscript{52} Public Health Scotland, Glasgow, Scotland, United
Kingdom

\textsuperscript{53} National Institute of Health Doctor Ricardo Jorge,
Lisbon, Portugal

\textsuperscript{54} National Virus Reference Laboratory, Dublin,
Ireland

\textsuperscript{55} Health Protection Surveillance Centre, Dublin,
Ireland

\textsuperscript{56} National Institute of Public Health of Kosovo,
Prishtina, Kosovo11This designation is without prejudice to positions on
status, and is in line with UNSCR 1244 and the ICJ Opinion on the Kosovo
Declaration of Independence. All references to Kosovo in this document
should be understood to be in the context of the United Nations Security
Council resolution 1244 (1999).

\textsuperscript{57} Ministry of Health and Medical Industry of
Turkmenistan, Ashgabat, Turkmenistan

\textsuperscript{58} National Center of Infectious and Parasitic
Diseases, Sofia, Bulgaria

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{\label{bibliography}}

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19. Bardsley M, Morbey RA, Hughes HE, et al. Epidemiology of respiratory
syncytial virus in children younger than 5 years in England during the
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Diseases 2023;23:56-66.

Table 1: Summary breakdown of RSV data by surveillance system for the
2020/21 (weeks 40/2020 to 39/2021) and 2021/22 (weeks 40/2021 to
39/2022) seasons and corresponding inter-seasonal periods, with
percentage positivity in brackets, and previous seasons (seasonal and
inter-seasonal periods), in the selection of countries included.
\selectlanguage{english}\textsuperscript{+}Reporting at least one specimen tested.
\selectlanguage{english}\textsuperscript{++} Note that the 50\% was based on 10 specimens tested
in one country.\selectlanguage{english}
\begin{longtable}[]{@{}llllllllll@{}}
\toprule
& & \textbf{2021/22 season} & \textbf{2021/22 season} & \textbf{2020/21
season} & \textbf{2020/21 season} & \textbf{2016/17-2019/20 seasons} &
\textbf{2016/17-2019/20 seasons} & \textbf{2016/17-2019/20 seasons} &
\textbf{2016/17-2019/20 seasons}\tabularnewline
\midrule
\endhead
& & \textbf{Seasonal period} & \textbf{Inter-season period} &
\textbf{Seasonal period} & \textbf{Inter-season period} & \textbf{Mean
during seasonal period} & \textbf{Range during seasonal period} &
\textbf{Mean during inter-season period} & \textbf{Range during
inter-season period}\tabularnewline
\textbf{Sentinel surveillance} & \textbf{Sentinel surveillance} &
\textbf{Sentinel surveillance} & \textbf{Sentinel surveillance} &
\textbf{Sentinel surveillance} & \textbf{Sentinel surveillance} &
\textbf{Sentinel surveillance} & \textbf{Sentinel surveillance} &
\textbf{Sentinel surveillance} & \textbf{Sentinel
surveillance}\tabularnewline
Number of countries \textsuperscript{+} & Number of countries
\textsuperscript{+} & 34 & 27 & 19 & 17 & - & 18 - 23 & - & 7 -
12\tabularnewline
Specimens tested & Regional totals & 36,040 & 19,197 & 21,803 & 5,076 &
15,796 & 13,853 - 18,026 & 1,338 & 1,121 - 1,532\tabularnewline
& Country ranges & 0 - 5,688 & 3 - 8,031 & 1 - 4,723 & 1 - 2,477 & 2 -
4,502 & 2 - 5,654 & 2 - 542 & 1 - 731\tabularnewline
Detections & Regional totals & 2,018 (6\%) & 375 (2\%) & 195 (1\%) & 316
(6\%) & 1,669 (11\%) & 1,461 - 1,905 & 15 (1\%) & 4 - 26\tabularnewline
& Country ranges & \vtop{\hbox{\strut 0 - 635}\hbox{\strut (0\% -
15\%)}} & \vtop{\hbox{\strut 0 - 103}\hbox{\strut (0\% - 15\%)}} &
\vtop{\hbox{\strut 0 - 78}\hbox{\strut (0\% - 7\%)}} &
\vtop{\hbox{\strut 0 - 175}\hbox{\strut (0\% - 22\%)}} &
\vtop{\hbox{\strut 0 - 312}\hbox{\strut (0\% - 50\%) ++}} & 0 - 430 &
\vtop{\hbox{\strut 0 - 11}\hbox{\strut (0\% - 2\%)}} & 0 -
20\tabularnewline
\textbf{Non-sentinel surveillance} & \textbf{Non-sentinel surveillance}
& \textbf{Non-sentinel surveillance} & \textbf{Non-sentinel
surveillance} & \textbf{Non-sentinel surveillance} &
\textbf{Non-sentinel surveillance} & \textbf{Non-sentinel surveillance}
& \textbf{Non-sentinel surveillance} & \textbf{Non-sentinel
surveillance} & \textbf{Non-sentinel surveillance}\tabularnewline
Number of countries \textsuperscript{+} & Number of countries
\textsuperscript{+} & 34 & 24 & 18 & 20 & - & 30 - 33 & - & 9 -
15\tabularnewline
Detections & Regional totals & 62,426 & 8,876 & 6,966 & 18,325 & 49,738
& 44,081 - 55,614 & 220 & 118 - 426\tabularnewline
& Country ranges & 0 - 14,071 & 0 - 1,955 & 0 - 5,454 & 0 - 6,983 & 0 -
11,888 & 0 - 16,456 & 0 - 61 & 0 - 164\tabularnewline
\textbf{SARI surveillance} & \textbf{SARI surveillance} & \textbf{SARI
surveillance} & \textbf{SARI surveillance} & \textbf{SARI surveillance}
& \textbf{SARI surveillance} & \textbf{SARI surveillance} & \textbf{SARI
surveillance} & \textbf{SARI surveillance} & \textbf{SARI
surveillance}\tabularnewline
Number of countries \textsuperscript{+} & Number of countries
\textsuperscript{+} & 16 & 11 & 2 & 7 & - & 5 - 10 & - & 1 -
3\tabularnewline
Specimens tested & Regional totals & 9,478 & 4,238 & 682 & 1,983 & - & -
& - & -\tabularnewline
& Country ranges & 28 - 2,370 & 2 - 1,630 & 94 - 588 & 27 - 736 & - & -
& - & -\tabularnewline
Detections & Regional totals & 948 (10\%) & 136 (3\%) & 144 (21\%) & 148
(7\%) & 200 & 178 - 227 & 7 & 3 - 15\tabularnewline
& Country ranges & \vtop{\hbox{\strut 0 - 355}\hbox{\strut (0\% -
60\%)}} & \vtop{\hbox{\strut 0 - 98}\hbox{\strut (0\% - 18\%)}} &
\vtop{\hbox{\strut 0 - 144}\hbox{\strut (0\% - 24\%)}} &
\vtop{\hbox{\strut 0 - 55}\hbox{\strut (0\% - 25\%)}} & 0 - 93 & 0 - 105
& 0 - 3 & 0 - 9\tabularnewline
\bottomrule
\end{longtable}

Table 2: Number of SARI detections (and percentage positivity when at
least ten specimens were tested per age group) per country by age group
(in years).\selectlanguage{english}
\begin{longtable}[]{@{}lllllllllllllllllllll@{}}
\toprule
\begin{minipage}[b]{0.03\columnwidth}\raggedright\strut
Country\strut
\end{minipage} & \begin{minipage}[b]{0.03\columnwidth}\raggedright\strut
2022 inter-season\strut
\end{minipage} & \begin{minipage}[b]{0.03\columnwidth}\raggedright\strut
2022 inter-season\strut
\end{minipage} & \begin{minipage}[b]{0.03\columnwidth}\raggedright\strut
2022 inter-season\strut
\end{minipage} & \begin{minipage}[b]{0.03\columnwidth}\raggedright\strut
2022 inter-season\strut
\end{minipage} & \begin{minipage}[b]{0.03\columnwidth}\raggedright\strut
2022 inter-season\strut
\end{minipage} & \begin{minipage}[b]{0.03\columnwidth}\raggedright\strut
2021/22 season\strut
\end{minipage} & \begin{minipage}[b]{0.03\columnwidth}\raggedright\strut
2021/22 season\strut
\end{minipage} & \begin{minipage}[b]{0.03\columnwidth}\raggedright\strut
2021/22 season\strut
\end{minipage} & \begin{minipage}[b]{0.03\columnwidth}\raggedright\strut
2021/22 season\strut
\end{minipage} & \begin{minipage}[b]{0.03\columnwidth}\raggedright\strut
2021/22 season\strut
\end{minipage} & \begin{minipage}[b]{0.03\columnwidth}\raggedright\strut
2021 inter-season\strut
\end{minipage} & \begin{minipage}[b]{0.03\columnwidth}\raggedright\strut
2021 inter-season\strut
\end{minipage} & \begin{minipage}[b]{0.03\columnwidth}\raggedright\strut
2021 inter-season\strut
\end{minipage} & \begin{minipage}[b]{0.03\columnwidth}\raggedright\strut
2021 inter-season\strut
\end{minipage} & \begin{minipage}[b]{0.03\columnwidth}\raggedright\strut
2021 inter-season\strut
\end{minipage} & \begin{minipage}[b]{0.03\columnwidth}\raggedright\strut
2020/21 season\strut
\end{minipage} & \begin{minipage}[b]{0.03\columnwidth}\raggedright\strut
2020/21 season\strut
\end{minipage} & \begin{minipage}[b]{0.03\columnwidth}\raggedright\strut
2020/21 season\strut
\end{minipage} & \begin{minipage}[b]{0.03\columnwidth}\raggedright\strut
2020/21 season\strut
\end{minipage} & \begin{minipage}[b]{0.03\columnwidth}\raggedright\strut
2020/21 season\strut
\end{minipage}\tabularnewline
\midrule
\endhead
\begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
0 - 4\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
5 - 14\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
15 - 64\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
[?]65\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
Total\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
0 - 4\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
5 - 14\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
15 - 64\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
[?]65\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
Total\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
0 - 4\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
5 - 14\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
15 - 64\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
[?]65\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
Total\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
0 - 4\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
5 - 14\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
15 - 64\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
[?]65\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
Total\strut
\end{minipage}\tabularnewline
\begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
Armenia\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
2 (5\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (0\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (0\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (-\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
2 (2\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
9 (6\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
2 (3\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (0\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (-\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
11 (3\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
11 (12\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (0\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (0\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (-\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
11 (5\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage}\tabularnewline
\begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
Belarus\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (0\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (0\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (-\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (-\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (0\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
5 (9\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
1 (3\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (-\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (-\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
6 (7\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage}\tabularnewline
\begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
Belgium \textsuperscript{+}\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
14 (35\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (-\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (-\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (0\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
14 (16\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
70 (20\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
4 (8\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
5 (2\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
4 (1\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
83 (9\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
41 (39\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
5 (45\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (0\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
7 (14\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
53 (28\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
122 (41\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
5 (26\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (0\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
9 (7\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
136 (28\%)\strut
\end{minipage}\tabularnewline
\begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
Bosnia and Herzegovina\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
6 (24\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (0\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (-\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (-\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
6 (17\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage}\tabularnewline
\begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
Croatia \textsuperscript{+}\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
4 (7\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (0\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (-\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (0\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
4 (1\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
6 (9\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (0\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
1 (-\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
1 (0\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
8 (2\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage}\tabularnewline
\begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
Malta\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (-\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (-\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (-\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
1 (1\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
1 (1\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (-\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (-\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (-\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
8 (3\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
8 (3\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (-\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (-\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (-\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
1 (1\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
1 (1\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (-\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (-\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (-\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
1\\
(0\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (0\%)\strut
\end{minipage}\tabularnewline
\begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
Montenegro\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
24 (67\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
2 (-\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
1 (-\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (-\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
27 (60\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage}\tabularnewline
\begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
Republic of Moldova\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (-\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (-\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (-\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (-\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (-\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
21 (26\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
2 (8\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
4 (6\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (0\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
27 (12\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage}\tabularnewline
\begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
Russian Federation\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
5 (2\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
1 (1\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (-\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (-\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
6 (2\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
40 (9\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
6 (3\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
1 (1\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (-\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
47 (6\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
18 (11\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
2 (5\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
1 (2\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (-\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
21 (8\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage}\tabularnewline
\begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
T\selectlanguage{ngerman}ürkiye\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
4 (1\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (0\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
1 (1\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (-\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
5 (1\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
258 (22\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
8 (4\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
8 (3\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (-\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
274 (17\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage}\tabularnewline
\begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
Ukraine\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
3 (17\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
2 (-\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (0\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (-\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
5 (7\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
2 (4\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
1 (8\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (0\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (-\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
3 (2\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage}\tabularnewline
\begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
Uzbekistan\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (0\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (0\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (-\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (-\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (0\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
64 (29\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
1 (3\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
2 (73\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
0 (-\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
67 (24\%)\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\strut
\end{minipage}\tabularnewline
\begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\textbf{Total}\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\textbf{29 (4\%)}\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\textbf{1 (0\%)}\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\textbf{1 (1\%)}\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\textbf{1 (0\%)}\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\textbf{32 (2\%)}\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\textbf{506 (20\%)}\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\textbf{28 (4\%)}\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\textbf{22 (2\%)}\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\textbf{13 (1\%)}\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\textbf{569 (11\%)}\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\textbf{72 (18\%)}\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\textbf{8 (10\%)}\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\textbf{1 (0\%)}\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\textbf{8 (6\%)}\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\textbf{89 (10\%)}\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\textbf{122 (41\%)}\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\textbf{5 (26\%)}\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\textbf{0 (0\%)}\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\textbf{9 (5\%)}\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\textbf{136 (25\%)}\strut
\end{minipage}\tabularnewline
\begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\textsuperscript{+}Country data has been updated upon request after data
collection date.\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\textsuperscript{+}Country data has been updated upon request after data
collection date.\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\textsuperscript{+}Country data has been updated upon request after data
collection date.\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\textsuperscript{+}Country data has been updated upon request after data
collection date.\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\textsuperscript{+}Country data has been updated upon request after data
collection date.\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\textsuperscript{+}Country data has been updated upon request after data
collection date.\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\textsuperscript{+}Country data has been updated upon request after data
collection date.\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\textsuperscript{+}Country data has been updated upon request after data
collection date.\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\textsuperscript{+}Country data has been updated upon request after data
collection date.\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\textsuperscript{+}Country data has been updated upon request after data
collection date.\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\textsuperscript{+}Country data has been updated upon request after data
collection date.\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\textsuperscript{+}Country data has been updated upon request after data
collection date.\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\textsuperscript{+}Country data has been updated upon request after data
collection date.\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\textsuperscript{+}Country data has been updated upon request after data
collection date.\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\textsuperscript{+}Country data has been updated upon request after data
collection date.\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\textsuperscript{+}Country data has been updated upon request after data
collection date.\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\textsuperscript{+}Country data has been updated upon request after data
collection date.\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\textsuperscript{+}Country data has been updated upon request after data
collection date.\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\textsuperscript{+}Country data has been updated upon request after data
collection date.\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\textsuperscript{+}Country data has been updated upon request after data
collection date.\strut
\end{minipage} & \begin{minipage}[t]{0.03\columnwidth}\raggedright\strut
\textsuperscript{+}Country data has been updated upon request after data
collection date.\strut
\end{minipage}\tabularnewline
\bottomrule
\end{longtable}\selectlanguage{english}
\begin{figure}[H]
\begin{center}
\includegraphics[width=0.70\columnwidth]{figures/RSV-Figure-1/RSV-Figure-1}

\end{center}
\end{figure}\selectlanguage{english}
\begin{figure}[H]
\begin{center}
\includegraphics[width=0.70\columnwidth]{figures/RSV-Figure-2/RSV-Figure-2}

\end{center}
\end{figure}\selectlanguage{english}
\begin{figure}[H]
\begin{center}
\includegraphics[width=0.70\columnwidth]{figures/RSV-Figure-3/RSV-Figure-3}

\end{center}
\end{figure}

\selectlanguage{english}
\FloatBarrier
\end{document}

