Serological screening for hydatidosis in households of surgical cases in central Tunisia

Household members of surgical cases of hydatidosis were screened for the disease in two high-risk districts in Central Tunisia. Seventy-four index cases were identified from the 1980-1984 surgical records of Sousse University Hospital. Household members over five years of age were tested by ELISA, and if positive by counterelectrophoresis (CEP) for detection of band 5. Positive subjects underwent a chest X-ray and echotomography (ECT). Eight of the 355 household members (2.2%) living in four different houses were serologically positive. All eight had a normal chest X-ray; a hepatic cyst was detected in seven of them. Five of the seven subjects in whom a cyst was diagnosed lived in two neighbouring houses (19 household members from the same family). Among these 19 subjects, six had been previously operated on for hydatidosis (cumulative rate: 11/19). The comparisons of these results with results obtained through community-based screening in the same area suggest that households members of patients are not at particularly high risk of hydatidosis.