BACKGROUND The United States Peace Corps has nearly 8000 Volunteers (PCVs) working in more than 70 countries, predominantly in the developing part of the world. The volunteers are challenged by many new and unfamiliar health problems, as a result of change in living conditions during their service. The goal of this study was to assess the health problems of PCVs in Madagascar, and to use this information to evaluate the effectiveness of the current PCV health support program. METHODS PCVs, finalizing their 2 years of service, were enrolled in the study. Data were retrieved from individual Peace Corps service medical records, the close of service (COS) physical evaluation, and a PCV questionnaire, which elicited additional self-reported health problems and concerns. RESULTS Sixty-nine PCVs took part in the study. Median age at COS was 24 years (95% CI 23-26 years), and the male/female ratio was 1 : 3.6 (15 males and 54 females). Skin, gastrointestinal and respiratory infections constituted the three most common reported health problems. Among the registered parasitic infections were ova and parasites in the stool (42.0%), confirmed and presumptive malaria (15.9%) and schistosomiasis (11.6%). Female PCVs more frequently reported dermatologic manifestations than male PCVs: postadolescent acne (48.2% vs. 13.3%) and telogen hair loss (33.3% vs. 6.7%). Amenorrhea, as the most commonly reported menstrual alteration during service, was reported by 15 (27.7%) female PCVs. CONCLUSIONS The PCVs in Madagascar encounter a broad range of health-related problems, most of which are preventable infectious diseases. Reinforcement of the preservice personal health-training curriculum later during service is needed. Reported dermatologic and menstrual disturbances in female subjects may be associated with stress-related estrogen imbalance. More studies are warranted to assess the stress impact of long-term travel on the female physiology.