Trends and patterns of varicella zoster virus infection in Kilifi: A population-based serosurvey.
About 40% of Kenyan young adults remain susceptible to varicella zoster virus infection.
Trends and patterns of varicella zoster virus infection in Kilifi: A population-based serosurvey.
There is limited epidemiologic data on varicella zoster virus (varicella zoster virus) infections from low- and middle-income countries including Kenya.
We aimed to describe the seroepidemiology of varicella zoster virus in Kilifi, Kenya, where varicella vaccine is not included in the national infant immunization program, in order to generate evidence to inform vaccine policy.
We conducted a retrospective serosurvey utilizing archived plasma and serum samples from cross-sectional population-based serosurveys conducted within the Kilifi Health and Demographic Surveillance System between 2009 and 2021.
most young Kenyan adults are immune, but a sizable minority remain unprotected from varicella zoster virus
We fitted an age-dependent catalytic model to estimate the force of infection (force of infection) in children aged 0.5-4, 5-9 and 10-14 years.
The overall population-weighted seroprevalence of varicella zoster virus immunoglobulin G antibodies among children aged 0-14 years was 38.4% (95% CI 27.5-49.5).
Age-specific seroprevalence rose from 13.3% (95% CI 5.8-21.6) in children aged 0-4 years to 60.9% (95% CI 45.0-76.2) in those aged 10-14 years.
Children aged 5-9 years had the highest force of infection (0.098; 95% CI 0.077-0.120) per susceptible year while mean age of infection was 24.3 years (95% CrI 17.6-30.1).
An infant varicella immunization program might avert disease across both paediatric and adult populations.