A descriptive analysis of dengue in Peace Corps Volunteers, 2000-2019

Background: Peace Corps Volunteers (PCVs) are a unique expatriate population at risk for dengue. Previous studies examined travelers or lacked demographic information about expatriates. We examined dengue incidence among PCVs before and after deployment of an electronic medical record (EMR) to assess temporal and demographic factors. Methods: Dengue cases within Peace Corps' Epidemiologic Surveillance System from 2000 to 2019 were identified using a standard case definition, and two timeframes were compared: pre-EMR 2000-2015 and post-EMR 2016-2019. Results: Annual infections occurred in a roughly 3-year cyclic pattern from 2007 to 2019. Incidence rate decreased from 1.35 cases per 100 dengue Volunteer-years (95% CI 1.28-1.41) in 2000-2015 to 1.25 cases (95% CI 1.10-1.41) in 2016-2019. Among PCVs who served from 2016 to 2019, the majority of infections occurred in females and 20-29 year olds, and 7% were medically evacuated. Among PCVs who served from 2015 to 2019, 21% were hospitalized in-country. Conclusions: Among PCVs, a non-significant decrease in dengue incidence occurred from 2000-2015 to 2016-2019. Annual infection rates peaked every three years, offering opportunities for targeted prevention efforts. Dengue infection in PCVs appears to mimic the overall demographic of Peace Corps. Expatriates like PCVs are at an increased risk for dengue infection compared to short-term travelers.