Using point-of-view cameras (Crittercams) to document potential risk behaviors for Guinea worm (Dracunculus medinensis) transmission in domestic cats in Chad, Africa

Abstract

Guinea worm (Dracunculus medinensis) infection has historically been a concern for humans, with parasite transmission occurring through drinking water containing infected cyclopoid copepods. However, infections in domestic dogs and cats in Chad, Africa increased between 2015 and 2021, and the epidemiology of these infections suggests that parasite transmission may also occur through ingestion of infected paratenic and transport hosts such as fish, reptiles, and amphibians. While previous work has examined transmission in domestic dogs, little is known about routes of transmission in domestic cats. In this study, we used animal-borne video cameras (Crittercams) provided by National Geographic’s Exploration Technology Lab to document the nighttime behaviors of domestic cats in Chad. Our objective was to identify cat and human behaviors that may be contributing to Guinea worm transmission. Cameras were deployed on 11 owned cats in August 2018 and videos were examined to identify risky behaviors, including stalking and capturing prey, scavenging, being fed by humans, and drinking water. Guinea worm infection data for individual cats was collected from owners; infection data for each village was collected from the Chadian National Guinea Worm Eradication Program (GWEP). Nine cats were observed eating items such as insects, fish, amphibians, reptiles, rodents, and millet-based grain balls; 8 cats were observed scavenging; 6 cats were observed stalking and capturing prey; 4 cats were observed being fed fish or grain balls by humans; and 5 cats were observed drinking water. Cats demonstrated risky behaviors on 14 of the 17 recorded nights and 10 of the 11 enrolled cats demonstrated at least one risky behavior. Cats were observed engaging in risky behaviors between 0 and 20 times per night: cats scavenged up to 11 times per night, ate up to 10 times per night, and hunted up to four prey items per night. Three of the enrolled cats were owner-reported to have a previous Guinea worm infection; one cat infection per village was reported to the GWEP. Overall, we successfully used Crittercams to document behaviors that could be associated with Guinea worm transmission in cats. Additional work is needed to determine the role of these behaviors in transmission of D. medinensis, and specifically, whether behaviors within the household increase opportunities for transmission to cats.