Cats & Toxoplasma

I am pregnant, do I need to put my cat down? This is a question I am asked again and again at the clinic, by women that have been told by their doctor that it is dangerous for the unborn baby to keep the cat at home. The reason for this outrageous allegation is a tiny parasite, the protozoo Toxoplasma gondii, which can be shed in the cats faeces. All pregnant women get tested for toxoplasmosis, and it is true that if you are pregnant, and get infected with toxoplasmosis for the first time, it is dangerous for the foetus. But that does not mean that you have to get rid of your cat! Toxoplasma is one of the most prevalent parasites infecting warm-blooded vertebrates, but only the cat can complete the parasites’  life cycle and pass infective oocysts (eggs) in the faeces. Humans can get infected in 3 ways: 

1.  Via oral ingestion of the infective oocysts, this is a possibility if you eat vegetables that haven´t been  washed enough, or if you fail to wash your hands before meals and might have been in contact with sand or dirt containing cat-faeces.
2. If you eat meat that hasn´t been cooked properly, or if you eat for example uncooked sausages or smoked ham, etc, because the parasite can sit in the muscle.
3. Transplacentally, this meaning the mother passes it on to her unborn baby via the placenta.

In the first two cases, we eat the parasite, and it moves on to the intestine. For the cat, this normally means that the parasite completes its life cycle and is shed with the faeces. In humans, and other mammals, it can sometimes happen that the parasite via the intestine invades the body, and forms cysts in organs, muscle and central nervous system. In the case of the mouse, it can then be eaten by a cat, and the parasite´s cycle starts all over again. The next 3 – 21 days the toxoplasma-oocysts are shed in the cats´ faeces, and 1-5 days after the eggs become infectious. The cat itself normally only gets ill, if its immune system was compromised beforehand, and under normal circumstances the cat will only shed infectious eggs after the very first time it´s infected. Therefore, if you are pregnant, you only need to follow some simple rules in order to keep your cat:

1. Don´t let the cat go out, and feed it proper cat-food, or well-cooked meat, because if it can´t eat anything that can give it the parasite, it can´t infect you. 
2. Empty the litter-tray every day, before the oocysts become infectious, and if you are the one in charge of that, use gloves. As cats are very fastidious and usually do not allow faeces to remain on their fur long enough to lead to oocyst-activation, you can touch your cat as normal, as long as you wash your hands regularly, which you should normally do anyway.