Epidemiology of human alveolar echinococcosis in Armenia.

Background: Since the 90s’ E.multilocularis infection in foxes is rising and central-eastern European countries had seen first Alveolar echinococcosis (AE) human cases. AE is considered to be a very rare disease in Europe with average incidences of 0.03-0.20/100,000 inhabitants/year. Because of a suitable orography, this study aims to confirm whether there are human AE cases in Armenia, identify areas at risk, and also estimate AE annual incidence. Methods: Retrospective AE case finding was carried out at main 6 multiprofile medical centers equipped with the most innovative diagnostic means. The medical records of all patients with liver surgery admitted between January 2008 and June 2020 were reviewed. A specific form was developed in EpiInfo v. 7.2. Annual national incidence was estimated using population denominators provided by the National Institute of Statistics (the population of Armenia is estimated at 2 963 243 people). Results: From September 2019 until June 2020, overall 11 AE cases have been identified. All patients were diagnosed at advanced stages, with subsequent poor prognosis and costly treatment. Confirmation was based on tissue biopsy results. Age ranged from 19-59 years with a median of 39yrs. E. multilocularis was detected in rural communities, mostly in the Gegharkunik region (6 cases, 55%). Annual average incidence of AE was 0.033 varying between 0.032 in 2008 and 0.1 in 2017. For comparison with Armenia, an annual incidence in France was 0.026/100,000 in 2008 (the population of France is estimated at 65 273 511 people). Conclusions: All cases were not notified by the surveillance system and the real prevalence of AE in the country is unknown. This young age could indicate widespread of infection in animals. Therefore, the burden of AE disease is difficult to estimate. The surveillance system in Armenia can be improved by the development of national guidelines for the prospective registry, AE awareness campaigns. Key messages: First-time identification of human AE in Armenia calls for implementation of surveillance with a case definition and registry of all cases. AE is an emerging, and so far silent threat in Armenia. [ABSTRACT FROM AUTHOR]