Do all cats have toxoplasmosis?

Toxoplasmosis scare is one of the reasons why a cat owner would decide to be parted from the pet. It is certainly frustrating to see a cat being left to an animal shelter by obviously loving owners because the wife is an expecting mother. Toxoplasmosis is a much publicized zoonotic disease. Infection in humans can result to encephalitis, a condition characterized by the inflammation of the brain. The risk is greater in pregnant people as the fetus can be infected. While cats are the only definitive hosts of the single celled called Toxoplasma gondii NOT ALL cats have toxoplasmosis.

Toxoplasmosis is caused by Toxoplasma gondii (T. gondii). This one celled parasite can be found in raw meat and in infected soil. All warm blooded animals can be infected with this parasitic disease. However, toxoplasmosis is more identified with cats as cats are the only definitive host of this one celled parasite. Toxoplasma gondii has to have two types of hosts – definitive and intermediate. Definitive host means that oocytes or eggs can only be produced by this organism in the definitive hosts which are cats. Cats get infected by ingesting infected prey or by eating raw or improperly cooked meat. Other animals (and even humans) infected by the organism will not produce oocyts. How are cats infected by T. gondii? A few days after eating infected prey or infected raw meat, the cat will start shedding oocytes with its feces. The organisms will continue producing eggs for about 14 days thus the cat will produce millions and millions of eggs that will be passed with the feces. Oocyte production will only stop when the cat’s immune system responds to the infection. The eggs that were passed by the cat will go through a process called sporulation. In about five days the sporulated eggs would now be infective. The eggs can now infect cats, other warm blooded animals and humans when oocytes from the environment are ingested like when contaminated fruits and vegetables are eaten. Infection can also occur if fresh meat containing tissues cysts are ingested and through contact with contaminated water. Although extremely rare, infection can occur through inhalation of dust containing sporulated oocytes. Once infected, the sporulated oocytes will form tissue cysts in different parts of the intermediate host’s body. Infection to other animals will occur if these tissue cysts are eaten.

Not all cats can be infected with toxoplasmosis. Indoor cats that are not allowed to hunt and eat prey or not fed raw meat have very low risk of being infected. T. gondii though is common in cats. In fact it is believed that about 50% of cats are infected by the organism but not all infections would result to toxoplasmosis. This disease usually occurs if the cat has a suppressed immune system as the pet’s immune response would not be able to put a stop to the production of oocyts and stop the rapid division of the tachyzoite form. Common symptoms of toxoplasmosis are fever, inappetance, vomiting, diarrhea and general feeling of malaise. This disease can affect the eyes. Affected cats would have inflamed retina. In pregnant cats, this parasitic disease can cause abortion and still births.

Toxoplasmosis is a dreaded parasitic infection especially by pregnant women. This disease can cause the baby to have visual, hearing and learning disabilities. The risk of the disease to the unborn child would make a pregnant cat owner decide to be parted from the pet. Contrary to common beliefs, petting and cuddling the pet or physical contact with an infected animal will not spread the infection. Instead of giving away the pet, the owner should take the necessary precautions to prevent toxoplasmosis.