Because of the seriousness of the disease and the level of infection, hydatidosis is a significant public health problem in Beirut. It occurs more frequently in predominantly Christian quarters than in predominantly Moslem quarters of the city. There was no significant difference between former patients and uninfected controls with regard to socio-economic status or hygienic condition of their homes. The only statistically significant difference observed between the infected and non-infected group was dog ownership. An estimate of the relative risk of owning and not owning a dog and acquiring hydatid disease in Beirut was calculated to be 21.5.
Former patients retested after operation showed persistently positive Casoni reactions up to 11 years after surgery. In contrast, some of the serological positives to the complement-fixation and indirect hemagglutination tests reverted to negative.