This is a disgusting, but necessary topic for everyone who is currently exposed. Many don't know of the danger.
BRAIN WORMS: 'Toxoplasma gondii'
It's worm-like, really, in only one stage of its life-cycle:
This parasite is a protozoa (one-celled creature) that dwells in the body of mammals and spreads by contact with infectious cat feces or ingestion of undercooked meat. The brain worm protects itself by encysting and is amazingly hardy, able to survive in hostile environments outside of the host body, even in salt water, dirt, or sewage treatment plants, for many months.
Only high prolonged temperatures are capable of killing the "oocysts" that protect the worm.
There is a serum test for toxoplasmosis which indicates it's one of the most common of humans infections throughout the world, mostly in warm climates in North and South America -- and France, where they eat undercooked meat, truffles and other unsavory things.
According to the Government's third National Health and Nutritional Assessment Survey (NHANES III) between 1988 and 1994, Toxoplasma "brain worms" were found in 22.5% of the US population, more than 60 million infestations.
The Toxoplasma gondii is unusual in that it can cause behavioral changes in the host, some of which seem to aid in its reproductive cycle. For example, mice infected with brain worms lose their fear of cat urine, and thus are more readily ingested by cats, leading to infestation of the predating cat, and further spread of the oocysts in that cat's feces over the next few weeks.
There is some evidence that infected humans exhibit behavioral changes, also, losing curiosity and becoming more tranquil in the face of danger, or on the other hand exhibiting various clinical pathologies.
"Brain worms" are the third leading cause of death attributed to food-borne illness in the United States.
According to the CDC, "...More that 60 million men, women, and children in the U.S. carry the Toxoplasma parasite, but very few have symptoms because the immune system usually keeps the parasite from causing illness."
Surfers and swimmers, in particular, are most at risk. But magazines such as "Surfer Boy" shrug off the problem, claiming that it only affects those with weakened immune systems; naturally, all the surfers imagine that they don't have weak systems.
But continued ingestion of viable brain worm oocysts can lead to huge numbers of them infesting the brain, causing continuous strain on the immune system so that other illnesses are potentially more likely and more serious. In addition, if the brain worms overwhelm the host immune system, they spread to other cells, reproducing and bursting those cells while multiplying the "brain worm breakout".