Tritrichomonas foetus is a single celled flagellated protozoan. It is more commonly known as a cause of reproductive disease in cows where it is passed from the prepuce (foreskin) of the bull to the vagina and uterus of the cow.

In cats however Tritrichomonas foetus colonizes the colon of the cat which results in large bowel diarrhea.

For a far more detailed look at the background of TF please read this article by Dr. Jody L Gookin.

What are the symptoms of Tritrichomonas foetus?

According to studies carried about by Dr. Jody L Gookin TF causes large bowel diarrhea. The diarrhea may come and go and sometimes it may contain fresh blood or mucus. The consistency of the diarrhea appears to vary from cat to cat, with some cats having cow pie like stools, and others having looser stools, on occasion a cat may dribble feces involuntarily.

The diarrhea may be gassy and malodorous. (In our experience it had the most awful smell)

In general, apart from the diarrhea the cats will appear otherwise healthy. Click on this link to read Indigo’s story.

How did my cat catch this?

It is believed that TF is passed on through the feces of an infected cat. At the moment it would seem that cats get it from ingesting the feces of another cat. It is possible that one cat will step in the feces of another cat in the litter box, and then become infected when they later groom themselves.

Can I catch Tritrichomonas foetus from my cat?

According to Doctor Jody Gookin "There has only been one published case of TF in a human and the person had undergone a bone-marrow transplant and was heavily immunosuppressed. TF was found in his urine, testicles and cerebrospinal fluid."

This would seem to suggest that under normal circumstances the transmission of TF to humans is unlikely, however, it is always wise to observe good sanitation procedures. Wash hands thoroughly with soap and water after cleaning or handling litter boxes, or contact with any fecal matter.

If you have young children, pregnant, or immunosuppressed individuals in the household, consult your physician and veterinarian for advice on further precautions that may need to be taken when handling a cat which you suspect may be infected with Tritrichomonas foetus.

How is Tritrichomonas foetus diagnosed?

There are several different methods of diagnosing TF. The first and least effective method is a direct Fecal Smear Examination. The probability of detecting TF using this method is low, less than 15%.

The second method is Fecal Protazoal Culture with the use of a commercially available product, the InPouch ™ TF testing kit available from Biomed Diagnostics. Biomed Diagnostics do not recommend that cat owners try to read this test themselves. They advise that results should be reviewed by an animal practitioner.

The third is the PCR (Polymerase Chain Reaction) test.

The PCR test is the most expensive of the three, and for catteries and shelters its cost may preclude its use for all of the cats in your care. It is currently $100 if conducted at NC State University but this is of course before the costs of your own vet, and the cost to transport the sample to them.

Speak to your vet about the tests available and based on your circumstances he or she will be able to advise you as to which test is right for you.

What is the prognosis for my cat now it has been diagnosed with TF?

Until Dr. Gookin published her findings last year there was no effective drug treatment. Thankfully this is no longer the case and a treatment has been identified.

Dr. Gookin has stated that “Most cats have spontaneous resolution of diarrhea in two years. More than half the cats remained positive for presence of the organisms however, up to 4-years after diagnosis, and possibly many can carry the infection for life."

In a multiple cat environment this could mean an endless cycle of re-infection. Therefore it is important that if you suspect your cat has TF, you have it tested and where necessary treated.

Spontaneous resolution of symptoms without treatment does not mean your cat is TF free. This may be less of an issue if you only have one cat, but in a multiple cat household, cattery, or rescue, your asymptomatic cat could infect others.

What is the treatment?

Until last year (2005) no effective treatment had been identified for the treatment of TF. However, treatment is now available.

For full details of the treatment for TF with Ronidazole please read this article.

Please consult your vet for advice on the diagnosis and treatment of Tritrichomonas foetus.