Toxoplasmosis in Cats and Humans

Since the question “Why don’t we just vaccinate cats?” was asked in class. I decided to do some research with this particular question in mind. It turns out that, currently, there is no vaccine to prevent toxoplasmosis in cats or humans. However, there is treatment. Cats are usually treated with a course of antibiotics called Clindamycin. Like humans, healthy cats who become infected with the parasite are usually asymptomatic and unless they contract feline immunodeficiency virus (FIV) or feline leukemia (FELV). Thus, cats do not need treatment unless their immune systems are compromised. I did find it curious that toxoplasmosis is treated with antibiotics, which, to my understanding, treat bacterial infections, and I would not think antibiotic drugs would prove effective against a parasite, which falls under the eukaryote family. Treatment of toxoplasmosis in humans is usually Pyrimethamine, an anti-malarial drug, taken in tandem with the antibiotic Sulfadiazine. Like cats, humans can also be treated with Clindamycin. Due to the nature of the disease and it’s close genetic make up of humans, especially when compared to viruses and bacteria, it is difficult to target the toxoplasmosis gondhii and the effects of the treatment can be hard on the body. In humans, treatment with Pyrimethamine can prevent the body from absorbing B vitamin folate as well as cause bone marrow suppression and liver toxicity. However cats are not spared the brunt of treatment, Clindamycin can cause severe diarrhea in both cats and humans.

In defense of cats everywhere, people, especially Americans, are not usually infected with toxoplasmosis from their precious Mr. Whiskers. Instead, most Americans contract toxoplasmosis through ingestion of raw/undercooked meat or unwashed produce that has contaminated soil on it. So, the best way to avoid getting toxoplasmosis in developed countries is to thoroughly cook or clean your food. So, some of this has been reiteration of what was covered in class, but I thought the treatment plans as well as the immune system similarities between cats and humans were noteworthy or at the very least, interesting. If you would like to read more or view the sites where I got my information, here are the links:

http://www.vet.cornell.edu/fhc/brochures/toxo.html

http://www.mayoclinic.com/health/toxoplasmosis/DS00510/DSECTION=causes