The flagellated protozoan parasite Tritrichomonas foetus is a common cause of large bowel diarrhea in cats in the United States. In this study, the prevalence of T foetus infection in the United Kingdom was examined. Of 111 diarrheic feline fecal samples, 16 (14%) were found to be positive for T foetus DNA. Significantly more of the infected cats were 1 year of age or younger, and pedigreed cats were significantly more likely to test positive than domestic crossbred cats. Siamese and Bengal cats were found to be overrepresented. T foetus may be an important, common, and previously unrecognized cause of diarrhea in cats in the United Kingdom.            

COMMENTARY: Significance of T foetus as a potential cause of large bowel diarrhea in cats has only recently been recognized in the United States. This study suggests a similar importance of the parasite in the United Kingdom and reports that younger, purebred cats are at apparently higher risk. Prevalence in the United States may be higher than that in the United Kingdom (31% in 1 study of cats at an American cat show), which might be related to a higher density of indoor pedigreed cats in the United States. Regardless, T foetus should be a differential for cats with persistent large bowel diarrhea, especially in younger cats and/or those from a household with pedigreed cats or another multicat establishment.

Prevalence of Tritrichomonas foetus infection in cats with diarrhea in the UK. Gunn-Moore D, McCann TM, Reed N, et al. J FelINE Med Surg 9:214-218, 2007.