Seroprevalence of HSV-1 and HSV-2 in the urban population of Qatar: a population-based study.

OBJECTIVES: Epidemiological data on herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) infections remain limited in the Middle East and North Africa. This study estimated HSV-1 and HSV-2 seroprevalence in the urban population of Qatar and examined associations with demographic characteristics. METHODS: A retrospective population-based cross-sectional study was conducted using archived serum specimens from a representative SARS-CoV-2 serosurvey undertaken in 2020 with a probability-based stratified sampling design. HSV-1 and HSV-2 IgG antibodies were measured using Mindray CL-900i chemiluminescence immunoassays. Associations were evaluated using logistic regression. RESULTS: Among 2002 archived specimens with sufficient volume, 2001 were tested for HSV-1 and 1981 for HSV-2. After excluding equivocal results, HSV-1 seroprevalence was 40.4% (789/1955; 95% CI 38.2% to 42.6%) and HSV-2 seroprevalence was 5.0% (99/1974; 95% CI 4.1% to 6.1%). HSV-1 seroprevalence increased from 16.4% (95% CI 12.8% to 20.6%) among those aged 10-19 years to approximately 50% among older age groups. HSV-2 seroprevalence increased steadily from 0.5% (95% CI 0.1% to 1.9%) among those aged 10-19 years to 13.2% (95% CI 7.8% to 20.6%) among those aged ≥60 years. No differences in HSV seroprevalence were observed between sexes. Some nationality differences were observed for HSV-1, with lower seroprevalence among individuals of Indian nationality, while HSV-2 showed small differences across nationalities. CONCLUSIONS: HSV-1 and HSV-2 seroprevalence in the urban population of Qatar were lower than regional and global estimates. Distinct age-specific patterns were observed, with early-life acquisition of HSV-1 and a gradual increase in HSV-2 seroprevalence across adulthood.