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.

An assessment of household water quality among Peace Corps volunteers in Guatemala.

BACKGROUND: Gastrointestinal (GI) illness is the most commonly reported health concern among Peace Corps Volunteers (PCVs) serving in Guatemala. This project identified water types and treatment and storage practices used by PCVs and measured select water quality parameters in their household water. METHODS: A survey about water types and practices was conducted of PCVs in Guatemala. The water type most frequently consumed in the household ("primary drinking water") and other water types present in the household ("secondary water") were tested for free chlorine residual (FCR) and for the presence of Escherichia coli and total coliforms. A negative binomial regression model was used to analyze data on incidence of self-reported GI illness. RESULTS: Tambo (commercially purified water in a 5-gal bottle) was the water type most frequently (64%) reported as primary drinking water in 39 PCV households. Most (74%) PCVs reported drinking water other than primary drinking water ≥1 day per week; the incidence rate of GI illness per PCV per month was significantly lower among PCVs who reported never consuming water other than primary drinking water compared to those who did (0.4 and 1.6 GI illnesses per PCV per month, respectively) (p < 0.05). E. coli was not detected in any primary drinking water sample, but was detected in 35% of secondary water samples. Total coliforms were detected in more than two-thirds of primary drinking water and secondary water samples. Nearly all water samples had an FCR of < 0.2 mg/L. CONCLUSIONS: Consuming primary drinking water exclusively likely contributes to reducing the rate of GI illness among PCVs. However, most PCVs reported drinking multiple water types, which may include contaminated secondary water types in the household. All water intended for consumption, including secondary sources within and outside the household, should be properly treated and safely stored.