Cystic echinococcosis in Bulgaria 1996-2013, with emphasis on childhood infections.

The objective of this study was to determine some features of cystic echinococcosis among children and adolescents, such as epidemiology, diagnosis, organ localization, treatment, and social and environmental factors favoring transmission of the disease. The 18-year study period (1996-2013) includes officially registered primary cases treated surgically, and/or with drug therapy, and/or with the puncture, aspiration, injection, reaspiration technique. Organ localization of the cysts and the most common diagnostic procedures were studied from the patients' medical records. Groups of diseased and healthy children were surveyed to outline some of the environmental and social factors influencing morbidity. From 1996 to 2013, the average annual incidence of cystic echinococcosis in the country was 6.7 per 100,000, but with significant variations in the incidence between different age groups. The hydatid cysts in children aged 0 to 9 years may most frequently be found in the lungs, in contrast to patients from other age groups. Almost 90% of the affected children had sustained contact with dogs. At present, among the countries of the European Union, Bulgaria holds the highest incidence and prevalence of cystic echinococcosis. Childhood echinococcosis remains a serious health problem for the country. Therefore, the study of cystic echinococcosis in children has important epidemiological significance concerning the intensity of transmission.