Clearing Tritrichomonas foetus from a Multi-Cat Household
Warning: this is a lengthy article!
The first time I had ever heard of Tritrich (also sometimes shorted to TF) was in the summer of 2010, in the car on the way back from the Abyssinian BAC (Breed Advisory Committee) Seminar in Worcestershire. Elisabeth Stark (Dushenka Russian Blues) and I were both given a lift by David Miskelly (Glendavan Abyssinians), and on the way home the conversation somehow turned to Tritrich. Tritrichomonas foetus is a protozoal parasite that was originally known as a reproductive problem in cattle, but for the past 20 or so years has also been known as a gut problem in cats. It is passed on through contact with wet faeces (it dies when it dries out), so is very easily passed on when cats are sharing litter trays.
David was telling us about how they had cleared this infection from their household and when he described the symptoms of liquid, strong-smelling diarrhoea, I commented that that sounded very much like Monty. Even the day that we collected him, from the Cumberland show, he came stinking of diarrhoea, having had an 'explosion' in his breeders' car on the way to the show. We knew that both his parents had also suffered from bad diarrhoea and he was rather in-bred, so we had always just assumed that it was genetic. Now I wondered if perhaps there was more to it after all, but we were so used to it, unpleasant as it was, that I had almost forgotten about it by the time we got home.
Seeing The Effects
We had our first litter of kittens at the time, and over the following few weeks they drove us half demented by weaning and then un-weaning repeatedly. One had died of a gut problem at 11 days old and by the time the others were about 11 weeks, one seemed absolutely fine, one was static in terms of weight gain, and the third was so unwell that we had to force feed him for a weekend, during which we genuinely thought he wasn't going to make it.
On the umpteenth visit to the vets I insisted that there had to be something we could do to find out what was causing the problem, so he suggested that we run a full faecal panel. I asked what that tested for and he reeled off a whole list of disorders, one of which sprung out at me - Tritrichomonas foetus. I asked him to confirm that he had said that Tritrich was one of the disorders on the list and when he confirmed that it was, I mentioned my earlier concerns about Monty and asked if we could test him as well. The vet's suggestion was that we test Monty only for Tritrich and do the full panel on the kittens.
Sure enough, Monty's panel came back positive for Tritrich, whilst the kittens came back positive for Tritrich and Clostridium perfringens Type A, which is one of the most common causes of food poisoning in humans. It occurs naturally in the guts of both humans and cats but if something causes an imbalance in the gut, can multiply out of control and cause serious problems. In the case of our kittens, the Tritrich had given the Clostridium a chance to proliferate.
The First Treatment
Our vet sought advice on clearing the problem from Professor Danielle Gunn-Moore, who is one of the UK's leading specialists in feline medicine, based at Dick Vet School in Edinburgh. She advised that there was no way to clear a multi-cat household but that since Monty seemed to have a permanent reaction to the parasite, we should treat him and then find him a new home away from the other cats. She said the kittens would be fine with a course of antibiotics to treat the bacterial (Clostridium) infection and that they would then clear the Tritrich themselves.
We therefore set about treating Monty with the extremely toxic Ronidazole capsules and, by the time he was half-way through his treatment, his permanent diarrhoea had cleared up: he had never produced a solid stool in all the time we had him and suddenly his digestion seemed to be completely normal. He also gained weight, filling out and looking less adolescent and girly, and his coat condition and even colour improved. The kittens did indeed respond to the antibiotics and by the end of the course seemed completely fine.
A Plan for the Others
In the meantime, however, I had started to research Tritrich, contacting Dr Jody Gookin (Associate Professor of Internal Medicine at North Carolina State University) and Dave Dybas (Highgait Abyssinians), who are probably the world's leading experts in Tritrich in cats and had written an owner's manual for the treatment of Tritrich. Through my online research, reading that manual, and talking to Dave, I formulated a treatment plan that would enable us to clear the whole household of this horrible parasite.
The treatment is known to fail about once in every ten times, so with 11 infected cats, chances were one of ours were going to fail their treatment. If the treatment fails and the cat is sharing a room with another cat at the time, the failed cat can reinfect the other cat even before the treatment has been completed. We decided that if we were going to mess about with doing the treatment and spend a fortune on tests and Ronidazole tablets, we might as well do everything we could to ensure success.
We therefore had the living-room as the 'infected room', one of the bedrooms as a 'clear room', and the other rooms for treatment. The cats were to be moved individually into one of the 'treatment rooms', tested for Tritrich and, if positive, given 14 days Ronidazole treatment. After the end of the 14 day treatment we had to wait a further two to three weeks, after which time we could test again, the test results taking about another 14 days. The most common test used at the time was the 'pouch test' but it's only 55% accurate, which my vet pointed out is barely more accurate than tossing a coin! The PCR test is over 97% accurate so we decided that we would need to test three times to achieve an almost 100% certainty of the cat being negative.
The Testing Begins
We obviously couldn't send our girls off to stud again until they had been confirmed clear of Tritrich so we decided to do them first, but since Dàrna had very young kittens at the time we discovered the infection, she couldn't be treated (we did test her, though). We had five rooms available to split the cats up, so we decided to do our two Devon Rexes as well, since they had a tendency to diarrhoea. None of the girls had shown signs of Tritrich, so imagine our surprise when we received the first set of results and it turned out that the girls were all positive but the Devons were both clear. Given that the bug is picked up through the sharing of litter trays, however, that actually made a lot of sense, because the Devons never actually stood into the trays, preferring instead to perch, swaying, on the edge of the tray.
They had still been very lucky not to have encountered any infected faeces, even when cleaning the other cats etc. and so our vet's recommendation was that we should find a new home for them. Initially we were going to refuse but then I worked out the minimum duration of the treatment programme and realised that we were going to have the cats split up for a minimum of about six months. The Devons are very gregarious cats who need a lot of time and attention and it wasn't going to be fair to keep them shut away by themselves for such a long period. We therefore sought their breeders' permission to re-home them and they ended up going to live with a couple who came to look at our kittens. We also found a new home for Monty, since he obviously had a particular susceptibility to the bug and we didn't want to risk him becoming re-infected.
Undertaking Treatment
The Ronidazole is provided in large capsules that are highly toxic, particularly to women, so Richard had to be the one to handle the actual capsules and even then it was with gloves on. We had to use pill-poppers in order to 'fire' the capsules well down the cats' throats, because once wet the capsules are extremely sticky and would be likely to get stuck if they didn't go down first time. We purchased protective overalls, plastic bootees for our feet and gloves for our hands, and had two sets of each outside every door so that we didn't risk transferring the infection from one room to the next.
In this way, we set about treating each of the cats in turn, in batches of five, and had only one failure, with Katie. She therefore had to be treated a second time, but at least the fact that she was by herself meant that it was only her needing treated twice. The wait for each set of post-treatment tests to come back seemed almost interminable but one by one the cats were all cleared.
Keeping Clear
As I mentioned before, Dàrna had just given birth when we found out that we had Tritrich in the house and she was one of the first batch of tests that we sent off, which came back positive. Given our experiences with the Devons managing to stay clear by not actually standing in the trays, and through talking to Dave Dybas again, we formulated a strategy for keeping her kittens clear. It would still take luck, because the kittens could pick the bug up by licking their mum, but we had to at least try.
We built a platform that was tall enough for the kittens to stand underneath, but was too low for Dàrna to go under. We put the kittens' litter tray underneath the platform so that the kittens could get into it but not their mum. Meanwhile, to stop the kittens getting into Dàrna's tray, we placed her covered tray on top of the platform. By the time the kittens were about five weeks old, they were starting to try and climb into Dàrna's tray, so we had to take her and her tray, away from them at that point. We then had a very anxious wait until the kittens were about ten weeks old, at which point we tested them to see if the process had been successful, hardly daring to hope. The results were exactly what we wanted, though, and all six kittens came up clear.
Since starting our experience with Tritrich, we have begun testing every cat coming into our house, for any reason, to ensure that we don't get it back. Initially, we tested each cat only once but one of the cats whom we bought in during 2013 (we now know which one) gave a false negative and ended up re-infecting most of the household, necessitating going through the experience of living in an isolation ward for a second time. Since then, we now test every incoming cat three times, including girls coming back from stud, new cats coming in and also our boys after they've had a girl in to stud. It doesn't mean that we think the stud owners, breeders or owners of the girls have Tritrich in their households, just that we're not prepared to take the chance - quite apart from anything else, our finances wouldn't withstand having to clear it again! The wisdom of the policy has been proven more than once, with positive results on four girls coming back from stud (studs of four different breeds!) and one kitten bought in, all of whom have since been successfully cleared of the parasite. The girls infected at stud were all pregnant and we've therefore had to use the same strategy as we used for Dàrna's litter in order to keep the kittens clear; waiting anxiously until we'd had the three negative results back on the kittens.
Our household has now been confirmed clear since the end of 2013 and we test regularly to ensure that it stays that way! If anyone wants any advice on clearing TF in multi-cat households I would recommend Dave Dybas but am happy to help wherever I can.