Instituto de Lengua Espanola, Department of International Health, and Division of Public Health, The Johns Hopkins University School of Hygiene and Public Health, College of Physicians and Surgeons, Columbia University, Genelabs Technology, Epidemiology Division, Naval Medical Research Institute, San Jose, Costa Rica
The seroprevalence and incidence of hepatitis A, B, C, and E virus infection were determined among North American missionaries (n = 328) serving in various geographic locations between 1967 and 1984. The mean age of subjects at entry into the study was 39.7 years (range 5–73 years); 65% were female; 89% had lived outside the United States before the study began. Seventy-eight percent of subjects served in sub-Saharan Africa during the study. At initial evaluation, 50.9% of the subjects had antibodies to hepatitis A virus (total anti-HAV), 8.5% to hepatitis B virus core antigen (total anti-HBc), 0.6% to hepatitis C virus (total anti-HCV by second-generation immunoblot assay), and 0% to hepatitis E virus (IgG anti-HEV). After an average period of service of 7.3 years (2,396 person-years total), 5.8% of the missionaries seroconverted to anti-HAV, 5.5% to anti-HBc, 0.6% to anti-HCV, and 0% to anti-HEV. This study indicates a relatively low risk of hepatitis C and E virus infection among missionaries while confirming the previously reported high risk of hepatitis A and B virus infection. Hepatitis A and B vaccination is recommended for long-term travelers to developing countries.