Toxoplasmosis

Toxoplasmosis is a parasitic disease caused by Toxoplasma gondii, an apicomplexan.[3] Infections with toxoplasmosis usually cause no obvious symptoms in adults.[2] Occasionally, people may have a few weeks or months of mild, flu-like illness such as muscle aches and tender lymph nodes.[1] In a small number of people, eye problems may develop.[1]... Toxoplasmosis is usually spread by eating poorly cooked food that contains cysts, exposure to infected cat feces... Up to half of the world's population is infected by toxoplasmosis, but have no symptoms.[7] In the United States, approximately 11% of people are infected, while in some areas of the world this is more than 60%. https://en.wikipedia.org/wiki/Toxoplasmosis

• Latent T. gondii infection in humans has been associated with a higher risk of automobile accidents,[173] potentially due to impaired psychomotor performance or enhanced risk-taking personality profiles.
• "Crazy cat-lady syndrome" is a term coined by news organizations to describe scientific findings that link the parasite Toxoplasma gondii to several mental disorders and behavioral problems.[91][92] The suspected correlation between cat ownership in childhood and later development of schizophrenia suggested that further studies were needed to determine a risk factor for children;[93] however, later studies showed that T. gondii was not a causative factor in later psychoses.

Jaroslav Flegr’s thinking is jarringly unconventional. Starting in the early 1990s, he began to suspect that a single-celled parasite in the protozoan family was subtly manipulating his personality, causing him to behave in strange, often self-destructive ways. And if it was messing with his mind, he reasoned, it was probably doing the same to others... When you add up all the different ways it can harm us, says Flegr, “Toxoplasma might even kill as many people as malaria, or at least a million people a year.”... T. gondii, reports Sapolsky, can turn a rat’s strong innate aversion to cats into an attraction, luring it into the jaws of its No. 1 predator. Even more amazing is how it does this: the organism rewires circuits in parts of the brain that deal with such primal emotions as fear, anxiety, and sexual arousal... The far more common victims of parasitic mind control—at least the ones we know about—are fish, crustaceans, and legions of insects, according to Janice Moore, a behavioral biologist at Colorado State University... Flegr began to make a connection that, he readily admits, others might find crazy: his behavior, he noticed, shared similarities with that of the reckless ant. For example, he says, he thought nothing of crossing the street in the middle of dense traffic, “and if cars honked at me, I didn’t jump out of the way.” He also made no effort to hide his scorn for the Communists who ruled Czechoslovakia for most of his early adulthood. “It was very risky to openly speak your mind at that time,” he says. “I was lucky I wasn’t imprisoned.”... Fortunately for him, 30 to 40 percent of Czechs had the latent form of the disease, so plenty of students were available “to serve as very cheap experimental animals.”... The subjects who tested positive for the parasite had significantly delayed reaction times. Flegr was especially surprised to learn, though, that the protozoan appeared to cause many sex-specific changes in personality. Compared with uninfected men, males who had the parasite were more introverted, suspicious, oblivious to other people’s opinions of them, and inclined to disregard rules. Infected women, on the other hand, presented in exactly the opposite way: they were more outgoing, trusting, image-conscious, and rule-abiding than uninfected women... Why men and women reacted so differently to the parasite still mystified him. After consulting the psychological literature, he started to suspect that heightened anxiety might be the common denominator underlying their responses. When under emotional strain, he read, women seek solace through social bonding and nurturing. In the lingo of psychologists, they’re inclined to “tend and befriend.” Anxious men, on the other hand, typically respond by withdrawing and becoming hostile or antisocial. Perhaps he was looking at flip sides of the same coin... Many schizophrenia patients show shrinkage in parts of their cerebral cortex, and Flegr thinks the protozoan may be to blame for that. He hands me a recently published paper on the topic that he co-authored with colleagues at Charles University, including a psychiatrist named Jiri Horacek. Twelve of 44 schizophrenia patients who underwent MRI scans, the team found, had reduced gray matter in the brain—and the decrease occurred almost exclusively in those who tested positive for T. gondii... When I ask Sapolsky about Flegr’s most recent research, he says the effects Flegr is reporting “are incredibly cool. However, I’m not too worried, in that the effects on humans are not gigantic. If you want to reduce serious car accidents, and you had to choose between curing people of Toxo infections versus getting people not to drive drunk or while texting, go for the latter in terms of impact.”... Webster is more circumspect, if not downright troubled. "The rat may live two or three years, while humans can be infected for many decades, which is why we may be seeing these severe side effects in people. We should be cautious of dismissing such a prevalent parasite."... E. Fuller Torrey agrees: “Schizophrenia did not rise in prevalence until the latter half of the 18th century, when for the first time people in Paris and London started keeping cats as pets. The so-called cat craze began among “poets and left-wing avant-garde Greenwich Village types,” says Torrey, but the trend spread rapidly—and coinciding with that development, the incidence of schizophrenia soared."... Just as worrisome, says Torrey, the parasite may also increase the risk of suicide. In a 2011 study of 20 European countries, the national suicide rate among women increased in direct proportion to the prevalence of the latent Toxo infection in each nation’s female population... Indoor cats pose no threat, he says, because they don’t carry the parasite. As for outdoor cats, they shed the parasite for only three weeks of their life, typically when they’re young and have just begun hunting.

When a woman acquires the infection for the first time while she is pregnant and transfers the parasite to her fetus, this causes a congenital parasitic infection. It can be a terrible disease when untreated or caught too late. In that setting, it can cause loss of sight, severe brain inflammation and permanent neurologic damage.

Appropriate safeguards for cat owners include keeping pet cats indoors, scooping litter daily (the oocysts take one to five days to become infectious after being shed) and washing your hands afterward, and letting someone else have scooping duty while you’re pregnant or immunocompromised.

The single most effective thing you can do to avoid contracting a disease from an animal or from the shelter environment is to: ALWAYS WASH YOUR HANDS AFTER HANDLING ANYTHING. In addition, make certain to wash before handling any food or putting your hands in your mouth or up to your face and eyes. Most diseases are spread through the oral route or by penetration through breaks in the skin or mucus membranes. This one simple step of handwashing will prevent the spread of most diseases by avoiding the route of infection... Other precautions: Wear gloves when cleaning and disinfecting cages, food and water bowls, litter pans, etc.; Use gloves and the proper equipment when handling dangerous animals to avoid injury. Wash hands using iodine based disinfectant soaps... Avoid letting animals lick your face or wounds.

It is unlikely that you would be exposed to the parasite by touching an infected cat, because they usually do not carry the parasite on their fur.

Allowing shelter cats to sit on your lap while you eat doesn’t sound like a good idea. There are plenty of other parasites and bacteria you could pick up that way.

Most healthy people don't require toxoplasmosis treatment. But if you're otherwise healthy and have signs and symptoms of acute toxoplasmosis, your doctor may prescribe the following drugs: Pyrimethamine (Daraprim); Sulfadiazine.