Toxoplasmosis, also known as toxo, is caused by one of the most common parasites, Toxoplasma gondii. It is found in humans worldwide, and in many species of animals and birds, but cats are the definitive host of the parasite. A healthy immune system can usually keep this parasite from causing illness, so pregnant woman and people who are immunocompromised should be especially careful. Toxoplasmosis can cause severe complications, and cannot be completely treated with medications. The best approach is prevention.
The single celled parasitic organism is only sexually reproduced in cats, which is why they remain the ultimate host for the organism. The complex life cycle of the parasite begins when a cat eats infected prey, usually a mouse or a bird. The organism then invades cells in the walls of the cat’s small intestines and forms oocysts. These cells next get eliminated in feces, and deposited into soil. Other animals become infected by ingesting soil that contains oocytes. T. gondii then eventually forms an inactive cyst that lodge mainly in the brain or muscles, but usually doesn’t cause any illness. Although the new host animal usually remains symptom-free and won't excrete oocysts, it can still transmit the parasite to any predator that eats it.
The pattern is similar in humans. After you're infected with T. gondii, the parasite forms cysts that can affect almost any part of the body, but often affects your brain and muscles, including the heart. If you're generally healthy, your immune system keeps the parasites inactive, and they remain in your body for life. But if your resistance is weakened by disease or certain medications, the infection can be reactivated, leading to serious complications. Although you can't catch toxoplasmosis from an infected child or adult, you can become infected if you come in contact with cat feces, ingest contaminated food or water, contaminated kitchen utensils, fruits or vegetables, or an infected...