Open Life Sci. 2016; 11: 524-532 while infections with E. granulosus s.s. which are highly infectious for humans are more commonly encountered in Romania and Hungary.Keywords: Echinococcus granulosus, genotype, DNA sequences, human, pig, central-eastern Europe
IntroductionThe larval stages of the tapeworm Echinococcus granulosus sensu lato (s.l.) are the causative agents of cystic echinococcosis (CE), one of the most important cestode infections causing morbidity and mortality in humans and significant economic losses in livestock. Around one million or more people are currently suffering from CE globally and the financial burden of the disease on the livestock industry is substantial, with up to two billion dollars lost annually [1]. Recent molecular phylogenetic analyses have revealed that E. granulosus is a complex of spesies/genotypes with at least five different species: E. granulosus sensu stricto (s.s.) (genotypes G1-G3), Echinococcus equinus (G4), Echinococcus ortleppi (G5), Echinococcus canadensis (G6-G10), and Echinococcus felidis ("lion strain") [2][3][4].CE remains one of the most important helminth zoonoses in many regions of Europe, especially the Mediterranean littoral (Spain, Italy, Greece and Turkey) and southeastern countries such as Bulgaria and Romania. The disease seems to be less prevalent in the UK, Central Europe, the Baltic States and the Scandinavian countries [5,6]. Surveys that addressed the incidence of CE over the last decade from central-eastern Europe has reported a relatively greater incidence in Romania (average incidence annual rate was 0.29 per 100,000 population) and Ukraine (0.30), whereas in Hungary (0.07), Poland (0.08) and Slovakia (0.10) lower numbers of human cases were documented [7]. This also is due to the fact that E. granulosus s.s., which is responsible for the majority Abstract: Central-eastern Europe is an endemic region for cystic echinococcosis where multiple species of intermediate hosts are commonly infected with Echinococcus granulosus sensu lato tapeworms of major medical and veterinary importance. Investigations of the genetic variation of 25 Echinococcus isolates from five countries (Slovakia, Romania, Ukraine, Hungary, Poland) were undertaken using three mitochondrial DNA markers. The 18 isolates from pigs derived from Slovakia and Ukraine and the four human isolates from Slovakia, Poland and Ukraine were identified as E. canadensis G7, whereas the three human isolates from Romania and Hungary were classified as E. granulosus sensu stricto G1. This study reports the first confirmed human case of E. granulosus s.s. in Hungary. The haplotype G7A with two polymorphic sites relative to the most common regional variant of E. canadensis G7 was recorded in both pigs from Ukraine and in a single pig isolate from Slovakia. The results of this study support the circumstantial evidence that E. canadensis G7 with low infectivity for humans is highly prevalent in the northern parts of the region (Poland, Slovakia, forest-steppe zone of Ukraine),