Immunology Division, Bureau of Laboratories, and General Parasitology Branch, Parasitology Division, Bureau of Laboratories, Center for Disease, Control, Public Health Service, U.S. Department of Health, Education, and Welfare, Departmento de Genética, Instituto do Biociências, Universidade Federal do Rio Grande do Sul, Instituto Nacional de Pesquisas da Amazônia (INPA), Department of Human Genetics, University of Michigan Medical School, Atlanta, Georgia 30333, Brazil
The prevalence of microfilaremia among Indians in 13 Amazon Indian villages was determined by examining Giemsa-stained peripheral blood smears and preparations from peripheral blood lymphocyte cultures. Mansonella ozzardi was the only species found in the 601 persons tested. Prevalence was highly village-specific, ranging from 0% in four villages to as high as 93% among persons aged 10 years and older in others. Comparisons of the two methods showed that the concentration effect of the peripheral blood lymphocyte culture preparations allowed the detection of a greater number of microfilaria-positive persons, especially women and children with lower levels of parasitemia.