I don't really care what people's opinions on household pets are. If they don't like dogs--fine. If they don't like cats--that's fine too. But I completely object to twisting scientific data to suit one's agenda, like this article. It makes one sound like a crooked politician.
First of all, a lot of people are already infected with Toxoplasmosis (more than 60 million people in the U.S. alone, according to the CDC) and the majority of those don't show any symptoms. That's because most people have normal immune systems that can contain the disease.
Toxoplasma gondii is a parasitic protozoan that can come in two different forms--the active tachyzoite with fast growth and the bradyzoite which is basically a dormant cyst. One reason why toxoplasmosis is so widely spread is the parasite's success in allowing the host's immune system to regulate its growth. Killing the host is a bad thing for the parasite so through sensing the signals from the immune system (of which the mechanism is still unknown), it switches from the tachyzoite form to the bradyzoite where it can lurk undetected. Some recent research suggest that maybe one of these regulators is a metabolism pathway that curiously is completely eliminated in Toxoplasma.
Typically people get Toxoplasmosis from contamination of cat feces or eating undercooked meat. Any living thing can get infected with Toxoplasma, but it's particularly important in the cat because the cat is the only known host where the parasite reproduces sexually. Cats don't show symptoms of infection either, but in rodents, the parasite attacks the brain (if you want to be dramatic, using mind control) so that the infected mouse or rat might run into danger rather than away from it. One can easily speculate from that how the parasite gets from the rodent to the cat.
The only people who have to worry about Toxoplasma are severely immunocompromised patients such as those with AIDS and pregnant women who get infected while they're carrying the child. Otherwise I wouldn't worry too much about the typical cat owner going "mad".
