Epidemiology of herpes simplex virus type 2 in China: Systematic review,
meta-analyses, and meta-regressions
Abstract
Background: Herpes simplex virus type 2 (HSV-2) infection is
prevalent and a significant public health problem. Understanding its
epidemiology will help assess the current HSV-2 prevention efforts and
inform future interventions in China. Methods: We followed
Cochrane and PRISMA guidelines for a systematic review and included
publications published in Chinese and English bibliographic systems
until March 18 th, 2023. We synthesized
seroprevalence, sero-incidence, and proportions of HSV-2 isolated in
genital ulcer disease (GUD) and genital herpes data. We used
random-effects models for meta-analyses and conducted meta-regression to
assess the association between population characteristics and
seroprevalence. Results: Overall, 21,849 articles were
identified, and 457 publications (1,051,035 participants) were included.
A total of 429 studies reported the overall seroprevalence rates (939
stratified measures), 5 reported seroincidence rates, 4 reported overall
proportions of HSV-2 isolation in GUD (8 stratified proportions), and 24
reported overall proportions of HSV-2 isolation in genital herpes (59
stratified proportions). Pooled HSV-2 seroprevalence among overall
populations was 14.9% (95% confidence interval (CI): 13.8-16.1%) and
was 7.9% (95% CI: 6.9-8.8%) among the general population.
Seroprevalence was highest among key populations (e.g., female sex
workers and men who have sex with men) (32.1% (95% CI: 27.8-36.5%)).
Among the general population, we found northeastern regions had a higher
HSV-2 seroprevalence (12.4%, 95% CI: 7.8-17.9%). HSV-2 seroprevalence
also increased with age. The pooled HSV-2 seroincidence rate was 4.3 per
100 person-years (95% CI: 1.0-7.6). Pooled HSV-2 seroprevalence among
GUD and genital herpes were 45.2% (95% CI: 29.0-61.9%) and 52.8%
(95% CI: 46.6-59.0%), respectively. We also found higher HSV-2
seroprevalence estimates in publications published in English
bibliographic databases than those in Chinese databases (20.5%
vs. 13.6%, risk ratio=1.10 (1.05-1.14)), indicating a potential
existence of language bias in publication. Conclusion: Around 1
in 12 among the general population and 1 in 7 among all included
populations were infected with HSV-2. The data revealed vulnerability to
HSV-2 infection among higher-risk populations calling for expanding the
intervention to prevent HSV-2 infection. It also revealed
heterogeneities in synthesized HSV-2 prevalence results, suggesting the
necessity to include Chinese bibliographic databases in conducting
systematic reviews and meta-analyses of this topic.