Herpes simplex virus type 2 cross-sectional seroprevalence and the estimated rate of neonatal infections among a cohort of rural Malawian female adolescents
- Christopher R Sudfeld1,
- Paul C Hewett2,
- Nadia N Abuelezam1,
- Satvika Chalasani3,
- Erica Soler-Hampejsek3,
- Christine A Kelly3,
- Barbara S Mensch3
- 1Department of Epidemiology, Harvard School of Public Health, Boston, Massachusetts, USA
- 2Population Council, Lusaka, Zambia
- 3Population Council, New York, New York, USA
- Correspondence to Dr Christopher R Sudfeld, Department of Epidemiology, Harvard School of Public Health, 667 Huntington Ave, Building 1, Room 1102, Boston, MA 02115, USA; and Dr Barbara S Mensch, Population Council, One Dag Hammarskjold Plaza, 9th Floor, New York, NY 10017, USA;
- Received 8 October 2012
- Revised 24 April 2013
- Accepted 21 May 2013
- Published Online First 21 June 2013
Objective To assess herpes simplex virus type 2 (HSV-2) seroprevalence among rural Malawian adolescent women and estimate the number of neonatal herpes infections among infants of these adolescents.
Methods A longitudinal cohort study of adolescents (14–16 years at entry) residing in rural Malawi was initiated in 2007 with annual observation. HSV-2 testing was introduced in 2010. In this study, we (1) determined, using cross-sectional analysis, risk factors for positive serostatus, (2) adjusted for non-response bias with imputation methods and (3) estimated the incidence of neonatal herpes infection using mathematical models.
Results A total of 1195 female adolescents (age 17–20 years) were interviewed in 2010, with an observed HSV-2 seroprevalence of 15.2% among the 955 women tested. From a multivariate analysis, risk factors for HSV-2 seropositivity include older age (p=0.037), moving from the baseline village (p=0.020) and report of sexual activity with increasing number of partners (p<0.021). Adjusting for non-response bias, the estimated HSV-2 seroprevalence among the total female cohort (composed of all women interviewed in 2007) was 18.0% (95% CI 16.0% to 20.2%). HSV-2 seropositivity was estimated to be 25.6% (95% CI 19.6% to 32.5%) for women who refused to provide a blood sample. The estimated number of neonatal herpes infections among the total female cohort was 71.8 (95% CI 57.3 to 86.3) per 100 000 live births.
Conclusions The risk of HSV-2 seroconversion is high during adolescence, when childbearing is beginning, among rural Malawian women. Research on interventions to reduce horizontal and vertical HSV-2 transmission during adolescence in resource-limited settings is needed.