Multimodal Assessment of The Transmission Risk of Neotropical Echinococcosis by Domestic Dogs in The Upper Maroni, French Guiana: Estimation of Canine Prevalence Using Molecular Biology and Survey of Human Exposure
Background: In French Guiana, several cases of polycystic neotropical echinococcosis caused by Echinococcus vogeli have been reported. Definitive hosts (the bush dog, Speothos venaticus, considered the main definitive host) and intermediate hosts (mainly the paca, Cuniculus paca, commonly hunted for its meat in the Amazon) are present in the region and participate in the parasite wild life cycle. To investigate potential transmission pathways, a field study was conducted in Amerindian communities along the Upper Maroni River, at the border between French Guiana and Suriname combining a household survey and the collection of domestic dog fecal samples.Methods: We conducted a two-phase study. First, a household survey was used to assess exposure-related practices, including dog ownership, feeding habits, hunting activities, and paca consumption. In parallel, canine fecal samples collected during two field missions in 2022 and 2024 were analyzed by real-time PCR targeting E. vogeli, E. granulosus, Toxocara spp., and cestodes, with sequencing confirmation when appropriate.Results: Sixty-two households were surveyed, representing 391 individuals, including children. Dog ownership was reported by 69% of households, and 60% reported hunting practices. Overall, 44% reported that their domestic dogs consumed paca more than once per year, and 48% reported human consumption of paca at a similar frequency. A total of 150 fecal samples were analyzed across five villages, of which 145 (97%) originated from domestic dogs. No samples tested positive for E. vogeli, while 11 were positive for other cestodes (7%), including Dipylidium caninum (n=4) and 11 for Toxocara spp. (7%).Conclusion: These findings suggest that canine infection, if present, occurs at a very low level, although survey data indicate substantial exposure to potential risk factors. Integrated eco-epidemiological approaches combining wildlife, domestic animal, and environmental sampling are needed to better elucidate transmission pathways of neotropical echinococcosis in Amazonian settings.