Epidemiology and spatial distribution of Echinococcus granulosus in sheep and goats slaughtered in a hyperendemic European Mediterranean area

Antonio Bosco,Maria Paola Maurelli,Rafael Antonio Nascimento Ramos,Laura Rinaldi,Kleber Régis Santoro,Edyniesky Ferrer-Miranda,Giuseppe Cringoli,Leucio Camara Alves,Paola Pepe,Maria Elena Morgoglione,Alessandra Amadesi,Paola Cociancic

doi:10.1186/s13071-021-04934-9

Abstract

BackgroundCystic echinococcosis (CE) is a worldwide parasitic zoonosis caused by the larval stage of Echinococcus granulosus sensu lato affecting livestock, particularly sheep and goats. However, often this parasitosis is underestimated. For this reason, this study aimed to evaluate the epidemiological features and spatial distribution of CE in sheep and goats slaughtered in a hyperendemic Mediterranean area.MethodsA survey was conducted in the Basilicata region (southern Italy) from 2014 to 2019. A total of 1454 animals (1265 sheep and 189 goats) from 824 farms were examined for hydatid cyst detection by visual inspection, palpation and incision of target organs. All the CE cysts were counted and classified into five morphostructural types (unilocular, multiseptate, calcified, caseous and hyperlaminated). Molecular analysis was performed on 353 cysts. For spatial analysis, a kriging interpolation method was used to create risk maps, while clustering was assessed by Moran’s I test.ResultsCE prevalence of 72.2% (595/824) and 58.4% (849/1454) was observed at the farm and animal levels, respectively, with higher values in sheep (62.9%) than goats (28.0%). The liver and lungs were the most frequently infected organs in both sheep and goats. Most of recovered cysts were of the calcified and multiseptate morphotypes. All the isolates were identified as E. granulosus sensu stricto (genotypes G1–G3). Spatial distribution showed a moderate clustering of positive animals.ConclusionThe findings of this study can be used to better understand the eco-epidemiology of echinococcosis and to improve CE surveillance and prevention programs in regions highly endemic for CE.Graphical abstract

Highlights

Cystic echinococcosis (CE) is a worldwide parasitic zoonosis caused by the larval stage of Echinococcus granulosus sensu lato affecting livestock, sheep and goats
Cystic echinococcosis (CE) is a parasitic zoonosis caused by taeniid tapeworms, belonging to the Echinococcus
CE was higher in sheep (796/1265, 62.9%; 95% 95% confidence interval (CI) 60.3–65.5%) than goats (53/189, 28.0%; 95% CI 22.1–34.8%) (P < 0.0001)

Summary

Introduction

Cystic echinococcosis (CE) is a worldwide parasitic zoonosis caused by the larval stage of Echinococcus granulosus sensu lato affecting livestock, sheep and goats. Cystic echinococcosis (CE) is a parasitic zoonosis caused by taeniid tapeworms, belonging to the Echinococcus. Bosco et al Parasites Vectors (2021) 14:421 organs (e.g. liver, lungs, spleen, heart) of infected intermediate hosts, sheep and goats. Humans are considered accidental intermediate hosts [2]. G1 is the most widespread genotype in intermediate hosts, as well as in human CE cases (88.4%) [4]. The global burden of CE has been estimated at approximately 1 million disability-adjusted life-years (DALYs),and the world’s livestock industry loss has been estimated at around $3 billion a year [5, 6]

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