Molecular Screening of Echinococcus spp. and Other Cestodes in Wild Carnivores from Central Italy

SIMPLE SUMMARY: Tapeworm infections are among the most relevant parasitic diseases in both human and animal health. Several tapeworms rely on wild animals to complete their life cycle, among them, taeniids from the Genus Echinococcus are particularly important as they are the causative agents of cystic and alveolar echinococcosis. The study’s aim was to perform a molecular screening of fecal samples collected from carcasses of wild carnivores from Central Italy using a multiplex PCR and Sanger sequencing approach. Out of 279 samples, 134 tested positive for either Taenia spp. Or Echinococcus granulosus sensu lato. Sanger sequencing was performed on every positive sample to produce a taxonomical attribution of the parasitic DNA. Echinococcus granulosus sensu stricto (genotype G3) was detected in only one Apennine wolf, whereas no sample tested positive for E. multilocularis. Other tapeworms that were commonly found in the sample pool were: Mesocestoides corti (syn. M. vogae), M. litteratus, Taenia serialis, and T. hydatigena. The results of the survey suggest that Echinococcus infections in the study area do not seem to be sustained by sylvatic cycles. The survey corroborates, yet again, the importance of passive surveillance of wild animals that can serve as reservoirs for zoonotic pathogens. ABSTRACT: Tapeworm infections are among the most relevant parasitic diseases in humans and animals. Tapeworms from the Genus Echinococcus are particularly important as they can cause cystic or alveolar echinococcosis. A molecular screening was performed on 279 fecal samples collected from carcasses of wild carnivores from Central Italy using PCR targeting diagnostic fragments of nad1, rrnS, and nad5 genes. Samples positive for either Taenia spp. or Echinococcus granulosus were sequenced to taxonomically identify the parasitic DNA. Of the 279 samples, 134 (48.0%) gave positive results in the multiplex PCR. Only one (0.4%) sample from an Apennine wolf tested positive for Echinococcus granulosus sensu stricto (genotype G3), whereas no sample tested positive for E. multilocularis. The most frequently detected tapeworms were: Mesocestoides corti (syn M. vogae) (12.9%), M. litteratus (10.8%), Taenia serialis (9.3%), and T. hydatigena (6.5%), other tapeworms were rarely detected. The results suggest that Echinococcus infections in Central Italy do not seem to be sustained by sylvatic cycles, confirming the absence of E. multilocularis in Central Italy. The survey corroborates, yet again, the importance of passive surveillance of wild animals that can serve as reservoirs for zoonotic pathogens, especially on wild canids that in other areas are strongly implicated in the transmission of E. granulosus and E. multilocularis.