Occurrence of Echinococcus granulosus Infection Among Owned Dogs in Kilosa District, Morogoro Region, Tanzania: A Copro-Antigen ELISA and PCR Analysis.

Abstract

Echinococcus is a taeniid cestode of public health concern with a cosmopolitan distribution that can be transmitted between animals and humans. Cystic echinococcosis caused by E. granulosus is among the neglected zoonotic tropical diseases highlighted by the World Health Organization, aiming to diminish the disease burden by 2030. Dogs are the definitive hosts of E. granulosus and play a key role in maintaining transmission cycles. Current data on the epidemiology of E. granulosus infection in dogs are limited in Tanzania, particularly in the Kilosa District. We conducted a cross-sectional study between October and December 2025 involving 204 owned dogs in six wards of the Kilosa District. We collected dog fecal samples into a clean Falcon tube (15 mL) and analyzed them by screening with copro-antigen enzyme-linked immunosorbent assay (ELISA) and confirmed them by conventional polymerase chain reaction (PCR) with sequencing and BLAST search in GenBank. The overall copro-prevalence of canine infection was 8.8% (18/204; 95% CI = 5.6-13.6) based on the copro-antigen ELISA. Further PCR analysis of the 18 ELISA-positive samples yielded a copro-PCR prevalence of 16.7% (3/18; 95% CI = 5.8-39.2). Sequencing and BLAST analysis revealed a complete sequence match with Echinococcus granulosus clone JKL.4 repeat region (Accession number: KR347168.1) from Mumbai, Maharashtra, India. Only deworming status was a significant predictor of canine infection, with dewormed dogs being 0.321 times (95% CI: 0.114-0.909; p = 0.03) less likely to have an infection than undewormed dogs. This is the first report of the presence of E. granulosus infection among owned dogs in the Kilosa District. There is a need for the One Health approach in controlling the disease and educating the public on proper protective measures.