Friday, July 12, 2013
A parasite that makes women shopaholics
Toxoplasma gondii is a parasite that can infect any warm-blooded animal, but does best in cats. T. gondii in cats undergoes sexual reproduction, producing new oocysts or spore cells. The amazing property of T. gondii is the technique it uses to spread from one cat to another. Infected cats distribute oocysts in their faeces and these oocysts can survive as long as a year. When rodents, birds or other animals ingest the oocysts they too become infected. Animals can then become infected by eating the flesh of an infected animal. Once an animal is infected, the T. gondii cells are distributed through the body by bloodstream and they pretty much say put inside muscle and brain cells. So how does the T. gondii re-enter its favourite host- The cat. When a mouse is infected by T. gondii, the parasite as usual moves into the muscles and brain of the mouse. Once inside the mouse's brain, the parasite alters its behaviour. The mouse becomes fat and lethargic and loses its fear of predators- Cats. Instead of fleeing away from cats, the mouse gets drawn towards it. So a fat, slow moving mouse makes an ideal cat food- and T. gondii gets to move into a new host. Scientist today believe that more than half the human population has T. gondii in them. It's mostly benign in humans, unless you have a compromised immune system, like people with HIV. Another group of people who should be careful are pregnant women. If a woman already has T. gondii infection in her then there is no risk, but if the infection is acquired during pregnancy then there is a 40% chance of the foetus getting infected and resulting in complications like blindness, damage to heart and liver and encephalitis. For these reasons pregnant women should avoid raw or partly cooked meat and cat litter boxes. There is also increasing evidence that past infection with T. gondii may trigger schizophrenia in some people, though this is not yet confirmed. T. gondii's influence on mouse brain, made scientist look closely in the human brain too. Now there is evidence that women infected with T. gondii spend more money on clothes, are more easy-going, warm hearted, had more friends and cared more about how they looked. They also were less trustworthy and had more relationships with men. Infected men on the other hand, tend to be less well groomed, likely to be loners and more willing to fight. They were also more likely to be suspicious and jealous and less willing to follow rules. So if you feel your lady is spending a lot on shopping, or if you think your man is shabby, blame it on the cat!