AN OUTBREAK OF ACUTE FASCIOLIASIS AMONG AYMARA INDIANS IN THE BOLIVIAN ALTIPLANO

Fasciola hepatica is a common and important parasite of sheep, cattle, and other ruminants. In May 1991, 30 persons with possible acute fasc ioliasis were identified by health care providers at a district hospit al in the Bolivian Altiplano, and two deaths were associated with this illness. A cross-sectional survey of a random sample of 30 (20%) of t he 148 households in the community and a case-control study were perfo rmed to determine the extent of the outbreak and the vehicle of transm ission, Ninety-one members from 23 of the 30 selected families partici pated in the cross-sectional survey, Twenty-one of the 91 members met the case definition for acute fascioliasis (illness since 16 February 1991 that was characterized by fever and abdominal pain plus serum IgG antibodies to F. hepatica), and 38 (49%) of 78 members had serum IgG antibodies to F. hepatica. If this rate is extrapolated to the entire community, an estimated 116 individuals (23% of 504) would have acute fascioliasis and 247 individuals (49% of 504) would have evidence of c urrent or previous infection. Case-control analysis indicated that the only factor associated with illness was eating kjosco (an aquatic pla nt) while tending animals in the fields; 27 (52%) of the 52 case-patie nts vs. 9 (14%) of the 66 controls ate kjosco (OR = 6.84; 95% CI = 2.6 0, 18.44). The cause of the two deaths attributed to fascioliasis coul d not be firmly established. Fascioliasis is a significant human healt h problem and is highly endemic in the Aymara Indian community in the Bolivian Altiplano. Efforts to prevent fascioliasis should include edu cating people to avoid eating uncooked aquatic plants such as kjosco.