EPIDEMIOLOGIC INVESTIGATION OF TAENIA-SOLIUM TAENIASIS AND CYSTICERCOSIS IN A RURAL VILLAGE OF MICHOACAN STATE, MEXICO

We performed a survey for taeniasis and cysticercosis among persons li ving in a Mexican village where Taenia solium infection in pigs was kn own to be enzootic. A standardized questionnaire was administered in a ll 577 households to obtain medical histories and information on demog raphic and environmental factors and on risk factors associated with t ransmission of infection. Serum and/or stool specimens were obtained f rom 1005 volunteers and examined for cysticercosis antibodies and inte stinal parasites. Faecal examination of 828 participants revealed infe ction by Taenia sp. in 2 (0.2%). Three additional cases of taeniasis w ere detected in individuals who evacuated proglottids after treatment with praziquantel. Of 1005 human serum specimens, 49 (4.9%) were posit ive in the cysticercosis immunoblot assay. Seropositivity increased wi th age and reached a peak in subjects aged 46-55 years (P < 0.05). A h istory of seizures was significantly associated with seropositivity (P < 0.05); approximately 25% of persons with such histories were seropo sitive. Histories of headache, dizziness, trembling, blurred vision, a nd vomiting were also significantly associated with positive immunoblo t assays. This study has demonstrated previously undiagnosed morbidity associated with T. solium neurocysticercosis and identified community behavioural and environmental practices that must be modified to prev ent continued transmission of cysticercosis and taeniasis.