Molecular epidemiology of Echinococcus species and other cestodes in free-roaming dogs in north-eastern Türkiye

Abstract

North-eastern Türkiye is highly endemic for human cystic (CE) and alveolar echinococcosis (AE), but the contribution of free-roaming dogs to transmission remains poorly understood. The molecular occurrence and diversity of Echinococcus species and other taeniid cestodes in free-roaming dogs were therefore evaluated across the region, comparing probe-based copro-real-time PCR (copro-qPCR) with a sieving/flotation-based classical PCR (S/F-cPCR) and with a classical polymerase chain reaction PCR performed directly on copro-DNA (copro-cPCR). A total of 494 canine fecal samples collected in 2019–2020 across 7 provinces were analysed. Copro-qPCR was used for Echinococcus granulosus sensu lato ( s.l. ) and E. multilocularis , and both copro-qPCR and copro-cPCR were used for Taenia spp., each followed by sequencing. Echinococcus granulosus sensu stricto ( s.s. ) was the most frequently detected species (20.0%), followed by E. multilocularis (5.7%) and E. canadensis (G6/G7) (0.4%). Among other cestodes, livestock-associated species ( Taenia hydatigena, T. multiceps, T. ovis ; 1–19.4%) and rodent/lagomorph-associated species ( T. crassiceps, T. serialis, T. pisiformis ; 0.4–0.6%) were identified, along with Mesocestoides spp. (8.9%). Taenia crassiceps is reported for the first time in dogs in Türkiye. Co-infections between domestic and sylvatic cycle parasites highlighted the bridging role of dogs in transmission dynamics. Methodological comparisons showed only fair agreement between copro-qPCR and S/F-cPCR for E. multilocularis , while moderate agreement was observed between copro-qPCR and copro-cPCR for Taenia spp. These findings demonstrate that free-roaming dogs link domestic and wildlife cycles, escalating zoonotic risks in a region where CE and AE are co-endemic. Targeted control strategies, including dog population management and public education, are urgently required to mitigate transmission.