Epidemiology of herpes simplex virus type 2 in the Middle East and North Africa: Systematic review, meta-analyses, and meta-regressions.

Herpes simplex virus type 2 (HSV-2) infection is a prevalent, sexually transmitted infection with poorly characterized prevalence in the Middle East and North Africa (MENA) region. This study characterized HSV-2 epidemiology in MENA. HSV-2 reports were systematically reviewed as guided by the Cochrane Collaboration Handbook and findings were reported following PRISMA guidelines. Random-effects meta-analyses and meta-regressions were performed to estimate pooled mean outcome measures and to assess predictors of HSV-2 antibody prevalence (seroprevalence), trends in seroprevalence, and between-study heterogeneity. In total, sixty-one overall (133 stratified) HSV-2 seroprevalence measures and two overall (four stratified) proportion measures of HSV-2 detection in laboratory-confirmed genital herpes were extracted from 37 relevant publications. Pooled mean seroprevalence was 5.1% (95% confidence interval [CI]: 3.6%-6.8%) among general populations, 13.3% (95% CI: 8.6%-18.7%) among intermediate-risk populations, 20.6% (95% CI: 5.3%-42.3%) among female sex workers, and 18.3% (95% CI: 3.9%-39.4%) among male sex workers. Compared to Fertile Crescent countries, seroprevalence was 3.39-fold (95% CI: 1.86-6.20) and 3.90-fold (95% CI: 1.78-8.57) higher in Maghreb and Horn of Africa countries, respectively. Compared to studies published before 2010, seroprevalence was 1.73-fold (95% CI: 1.00-2.99) higher in studies published after 2015. Pooled mean proportion of HSV-2 detection in genital herpes was 73.8% (95% CI: 42.2%-95.9%). In conclusion, MENA has a lower HSV-2 seroprevalence than other world regions. Yet, 1 in 20 adults is chronically infected, despite conservative prevailing sexual norms. Seroprevalence may also be increasing, unlike other world regions. Findings support the need for expansion of surveillance and monitoring of HSV-2 infection in MENA.

Epidemiology of herpes simplex virus type 2 in Europe: systematic review, meta-analyses, and meta-regressions.

Background: Herpes simplex virus type 2 (HSV-2) infection is a globally prevalent, life-long, sexually transmitted infection. This study characterized HSV-2 seroprevalence in Europe for various at-risk populations and proportions of HSV-2 detection in genital ulcer disease (GUD) and in genital herpes. Data on neonatal herpes and HSV-2's contribution to HIV transmission were also reviewed. Methods: Cochrane and PRISMA guidelines were followed to systematically review, synthesize, and report HSV-2 related findings. The search was conducted in PubMed and Embase databases up to February 20, 2022. Any publication reporting data on the outcome measures was included. Meta-analyses and meta-regressions were conducted. Findings: 211 relevant reports were identified, including 12 overall incidence measures, 294 overall (813 stratified by factors such as age and sex) seroprevalence measures, 13 overall (15 stratified by sex) proportions of HSV-2 detection in clinically diagnosed GUD, and 70 overall (183 stratified by factors such as age and sex) proportions of HSV-2 detection in laboratory-confirmed genital herpes. Pooled mean seroprevalence was 12.4% (95% CI: 11.5-13.3%) among general populations, 27.8% (95% CI: 17.5-39.4%) among men who have sex with men, 46.0% (95% CI: 40.1-51.8%) among people living with HIV and people in HIV discordant couples, and 63.2% (95% CI: 55.5-70.6%) among female sex workers. Most measures showed heterogeneity in HSV-2 seroprevalence. The pooled mean seroprevalence among general populations increased with age and was 0.65-fold (95% CI: 0.58-0.74) lower in men than women. Seroprevalence decreased by 1% per calendar year. Pooled mean proportions of HSV-2 detection in GUD and in genital herpes were 22.0% (95% CI: 15.3-29.6%) and 66.0% (95% CI: 62.9-69.1%), respectively. HSV-2 detection in genital herpes cases was 1.21-fold (95% CI: 1.10-1.32) higher in men compared to women and decreased by 1% per calendar year. Incidence of neonatal herpes indicated an increasing trend. Interpretation: Although seroprevalence is declining, a significant proportion of Europe's population is infected with HSV-2. HSV-2 accounts for approximately one-fifth of GUD cases and two-thirds of genital herpes cases. Findings support the need to invest in HSV-2 vaccine development, and sexual and reproductive health services. Funding: Qatar National Research Fund [NPRP 9-040-3-008] and pilot funding from the Biomedical Research Program at Weill Cornell Medicine in Qatar supported this study.