The complications and controversies surrounding feline trichomoniasis, regarded as one of the most common infectious causes of large bowel diarrhoea in cats, are explored in a review article published this month in the Journal of Feline Medicine and Surgery.
Over the past two decades, the protozoan Tritrichomonas foetus has come to be recognised as a cause of chronic colitis in cats worldwide.
The culprit, T. foetus, a teardrop shaped, highly motile flagellate, is thought to be transmitted from cat to cat via the fecal-oral route; cats acquired from breeding catteries and shelters are at increased risk of infection, as dense housing conditions favour this route of transmission.
T. foetus also infects cattle, in which it is sexually transmitted and a potential cause of abortion and infertility.
In their paper, authors Dr Jody Gookin and colleagues at the College of Veterinary Medicine, North Carolina State University, explained that feline trichomoniasis is resistant to all commonly used antiprotozoals.
Currently, the only drug that has been demonstrated to be effective in cats is ronidazole, but this agent has a narrow safety margin and clinical resistance is increasingly recognised.
The authors wrote that there remain many unanswered questions that are pivotal to future progress: Are feline and bovine T. foetus genotypes truly biologically distinct, residing in separate hosts, or is there the potential for cross infection between cattle and cats? Should all cats in contact with a Tritrichomonas species infected cat also be treated? What is the long-term effect of Tritrichomonas species infection on feline gastrointestinal health, and can safer and more effective drugs for treatment of the infection be identified?