Abstract

Background and Aim: Cystic echinococcosis is a neglected parasitic zoonosis caused by the larval stage of the cestode Echinococcus granulosus sensu lato. This study aimed to determine the coprevalence of E. granulosus sensu lato in owned domestic dogs and to identify associated epidemiological risk factors in a high-altitude endemic district of the Peruvian Andes.

Materials and Methods: An analytical, community-based, cross-sectional study was conducted in the district of Ascension, Huancavelica, Peru (altitude 3,650 m), from April to December 2021. Simple random sampling selected 159 households across nine communities. Fresh fecal samples were collected from 453 owned dogs. Diagnosis combined conventional coproparasitological examination using the simple flotation technique for helminth eggs and copro-polymerase chain reaction targeting the mitochondrial cox1 gene for specific detection of E. granulosus sensu lato DNA. An interviewer-administered epidemiological questionnaire captured owner demographics, household characteristics, dog management practices, and cohabitation with livestock. Associations were assessed using the Chi-square test, odds ratios, and 95% confidence intervals; statistical significance was defined as p < 0.05. Data were analyzed using SPSS v.25 software (IBM Corp., Armonk, NY, USA).

Results: The overall coprevalence of E. granulosus sensu lato was 10.8% (49/453; 95% CI: 7.9–13.8). Village-specific prevalences were highest in Pastales (29.4%) and Sacsalla (16.7%). Canine positivity showed significant associations with household cohabitation with donkeys (p < 0.05) and alpacas (p < 0.01). Households of copro-polymerase chain reaction (PCR)-positive dogs raised significantly more alpacas (mean = 293) than households of negative dogs (mean = 215) (p < 0.01). Concurrent gastrointestinal helminths included Strongyloides sp. (7.2%), Taenia sp. (6.6%), Toxascaris sp. (1.8%), and Trichuris sp. (0.4%). Statistically significant coinfection patterns were observed between E. granulosus sensu lato and both Taenia sp. and Strongyloides sp. (p < 0.01 each). No significant associations emerged with dog sex, owner educational level, housing materials, water source, or sanitation infrastructure.

Conclusion: Active transmission of E. granulosus sensu lato is confirmed in domestic dogs in this high-altitude Andean setting, perpetuated primarily by the dog–alpaca epidemiological interface and likely facilitated by unsupervised home slaughter and raw offal feeding practices. The moderate-to-high coprevalence, together with identified livestock cohabitation risk factors and helminth coinfection patterns, indicates a persistent zoonotic threat to human health. Implementation of a One Health strategy, including quarterly praziquantel-based canine deworming, regulation of domestic slaughter, secure offal disposal, and sustained community health education, is urgently needed to interrupt the domestic cycle and reduce the burden of human cystic echinococcosis in the region.

Keywords: cox1 gene, copro-PCR, cystic echinococcosis, DNA detection, Echinococcus granulosus, mitochondrial markers, molecular epidemiology, polymerase chain reaction