Species and genotypes belonging to Echinococcus granulosus sensu lato complex causing human cystic echinococcosis in Europe (2000–2021): a systematic review

Abstract

Background This study aimed to fill a gap of knowledge by providing a quantitative measure of molecularly identified species and genotypes belonging to Echinococcus granulosussensu lato (s.l.) causing human cystic echinococcosis (CE) in Europe during the period 2000–2021. As these species and genotypes are characterized by genetic, animal host and geographical differences, studying the E. granulosuss.l. complex is epidemiologically relevant. Methods A systematic review (SR) was conducted on the basis of both scientific and grey literature considering primary studies between 2000 and 2021 in four databases. From a total of 1643 scientific papers, 51 records were included in the SR. The main inclusion criterion for this study was the molecular confirmation of E. granulosuss.l. at the genotype/species level as a causative agent of human CE cases in selected European countries. Results Relevant data were obtained from 29 out of 39 eligible European countries. This SR identified 599 human molecularly confirmed echinococcal cysts: 460 (76.8%) identified as E. granulosussensu stricto (s.s.), 130 (21.7%) as E. canadensis cluster (G6/7 and G10), 7 (1.2%) as E. ortleppi (G5), and 2 as E. vogeli (0.3%). Three geographical hotspots of human CE caused by different species of the E. granulosuss.l. complex were identified: (1) E. granulosuss.s. in Southern and South-eastern Europe (European-Mediterranean and Balkan countries); (2) E. canadensis (G6/7) in Central and Eastern Europe; (3) E. ortleppi in Central and Western Europe. This SR also identified data gaps that prevented a better definition of the geographical distribution of the Echinococcus granulosuss.l. species complex in Europe: western Balkan countries, part of Central Europe, and Baltic countries. Conclusions These results mandate longitudinal, multi-centre, intersectoral and transdisciplinary studies which consider both molecular and clinical epidemiology in animals and humans. Such studies would be valuable for a better understanding of the transmission of the E. granulosuss.l. species complex and their potential clinical impact on humans. Graphical Abstract

The European Union One Health 2021 Zoonoses Report

“…Surveillance of the latter parasite therefore depends on national regulations. Approximate geographical distribution of E. granulosus sensu stricto, E. canadensis and E. ortleppi species causing human cystic echinococcosis in Europe are reported in Figure 27 (Casulli et al., 2022 ).…”

Unveiling the incidences and trends of the neglected zoonosis cystic echinococcosis in Europe: a systematic review from the MEmE project

“…Nationality of patients retrieved from the records included in this systematic review was used as a proxy for the identification of locally acquired and imported cases at the national level, such that nationals were assumed to have been infected in their home country even if they currently resided in a different country. 25…”

The spatial distribution of cystic echinococcosis in Italian ruminant farms from routine surveillance data

“…E. granulosus s.s. (G1) is responsible for the majority of infections in humans worldwide (7). In Italy, cases in intermediate hosts including humans are predominantly caused by E. granulosus s.s. (8). E. granulosus s.s. is also considered to be responsible for most cases in cattle across Europe (9).…”