Detection of Giardia duodenalis Zoonotic Assemblages AI and BIV in Pet Prairie Dogs (Cynomys ludovicanus) in Bangkok, Thailand.

Abstract

Simple SummaryPrairie dogs are native to the United States, Canada, and Mexico. They have been brought to Thailand and become popular as exotic pets and providing humans with exotic pets in close-contact environments. Prairie dogs have been known to carry several waterborne protozoan pathogens. One of those pathogens is known as Giardia, a flagellate protozoan parasite which can cause gastrointestinal illness in humans and other animals. This study has identified the Giardia parasite in the feces of prairie dogs. There were 13% of prairie dogs pets in Bangkok, Thailand that carried the Giardia parasite. We also found that the parasite was categorized as a human parasite. Therefore, there was potential risk that prairie dogs could contract a Giardia infection from humans as a source, and that humans could receive the parasite from their exotic pets via the fecal-oral route in shared environments. We suggest that exotic pet owners should pay more attention to effective sanitation and provide clean food and water for their exotic pets. Owners should bring their exotic pets for veterinary services and screening of zoonotic pathogens using fecal examination regularly. Treatment can successfully cure the infected pets as well as prevent the spreading of pathogen to the environment. Giardia is a flagellate protozoa that can be transmitted via direct contact and by consuming contaminated water. It is pathogenic in humans and various other animals, including exotic pets. Pet prairie dogs are popular in Thailand, but they have not been investigated regarding giardiasis. Giardia infection was measured, and genetic characterization was performed to investigate the zoonotic potential of Giardia carried by pet prairie dogs. In total, 79 fecal samples were examined from prairie dogs visiting the Kasetsart University Veterinary Teaching Hospital during 2017–2021. Simple floatation was conducted. Two Giardia-positive samples were submitted for DNA extraction, PCR targeting the Giardia ssu rRNA, tpi and gdh genes was performed, and genetic characterization using sequencing analysis was conducted. Risk factors associated with Giardia infection were analyzed. Giardia infection was found in 11 out of the 79 pet prairie dogs (13.9%). Giardia infection was significantly higher in male prairie dogs (p = 0.0345). Coccidia cysts (12.7%), the eggs of nematodes (6.3%), and amoeba cysts (2.5%) were also detected. Genetic characterization of the two Giardia-positive samples revealed that they were G. duodenalis assemblage A, sub-genotypes AI and assemblage B, and sub-genotype BIV, the zoonotic assemblages. This was the first report of Giardia infection in pet prairie dogs in Bangkok, Thailand. The results revealed that these pet prairie dogs in Thailand were infected with zoonotic assemblages of G. duodenalis sub-genotype AI, which might have been derived from animal contaminants, whereas sub-genotype BIV might have been derived from human contaminants. Owners of prairie dogs might be at risk of giardiasis or be the source of infection to their exotic pets.