Prevalence, risk factors, and molecular identity of Giardia infections in dogs in Nairobi County, Kenya

Giardia duodenalis is an emerging zoonotic protozoan parasite that is significantly affecting the health and welfare of dogs in Nairobi County, Kenya. There is limited data on canine giardiasis in Kenya. A cross-sectional study was conducted to determine the prevalence, risk factors and molecular identity of G. duodenalis infections in dogs in Nairobi County, Kenya. Four hundred fecal samples were collected from randomly selected dogs and subjected to Giardia SNAP test which is a rapid antigen ELISA test to determine the Giardia antigen in the faeces. Positive fecal samples were subjected to molecular analysis through PCR and thereafter sequencing to determine the circulating Giardia genotypes. A Spatial Bernoulli model in SaTScan was used to investigate clustering of Giardia infection in dogs within Nairobi County. A questionnaire was administered to the dog owners to capture data on risk factors for Giardia infection in dogs. Multivariate analysis was used to determine the association between the occurrence of infection and the predicted risk factors. The overall prevalence of Giardia infection in dogs in Nairobi County, Kenya in this study was 22.3%. The risk of infection was 0.99 times during wet season and 0.22 times in young dogs < 12 months.  Roaming/stray or dogs that were never housed in kennels had 3.04 times the chances of contracting the infection. Spatial analysis showed two clusters with a high risk of Giardia infection within Nairobi County. Zoonotic assemblages A and B and a mixed infection of both were also isolated in dogs in Nairobi County, Kenya. In conclusion, young and roaming or stray dogs have a higher risk of Giardia infection with the risk of infection being high during the wet season. Dogs within Nairobi County harbor zoonotic assemblages A and B which could pose a public health risk to humans. Key words: Dogs, Giardia duodenalis, prevalence, risk factors, zoonotic genotypes.