Researchers may have discovered the most infectious parasite in the world. Toxoplasma gondii is a microscopic creature that scientists believe could infect up to 50 percent of people. The parasite is easily transmittable and is carried for life once a person has been infected.
In addition to serious eye disease, toxoplasmosis can cause severe lung or brain disease for a person with weakened immunity. Rarely, the infection can show up in other tissues throughout the body. Lung infection may cause: Breathing problems.
Toxoplasmosis is caused by the protozoan parasite Toxoplasma gondii. In the United States it is estimated that 11% of the population 6 years and older have been infected with Toxoplasma. In various places throughout the world, it has been shown that more than 60% of some populations have been infected with Toxoplasma.
Toxoplasmosis is considered to be a leading cause of death attributed to foodborne illness in the United States. More than 40 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.
How do people get toxoplasmosis? A Toxoplasma infection occurs by one of the following: Eating undercooked, contaminated meat (especially pork, lamb, and venison) or shellfish (for example, oysters, clams or mussels).
Toxoplasma gondii – a protozoan – occurs worldwide in mammals and birds. Asymptomatic infection in humans is common. The main host in Australia is the domestic cat, which become infected mainly through eating small infected mammals, including rodents and birds.
One in 150 Australians have retinal scars caused by the Toxoplasma parasite, according to new Flinders University analysis.
No, you do not have to give up your cat. Owning a cat does not mean you will be infected with the parasite. It is unlikely that you would be exposed to the parasite by touching an infected cat because cats usually do not carry the parasite on their fur.
Because of the cysts left behind by T. gondii, toxoplasmosis may never be fully cured. Medication can treat an active infection, but it doesn't destroy the cysts. If you have a healthy immune system, the cysts shouldn't reactivate.
Symptoms of toxoplasmosis include fever, swollen glands and muscle aches. Most people who become infected with Toxoplasma have no symptoms. If people develop symptoms, they usually begin 1 to 3 weeks after being exposed to the parasite. Symptoms usually last for 2 to 4 weeks.
Your brain on Toxoplasma
Infection with Toxoplasma does not usually produce symptoms in humans unless their immune systems are compromised, but the parasites remain in the body for life as latent tissue cysts. These tissue cysts are commonly found in the brain, heart and skeletal muscle.
A total of 14,181 cases were included in the analysis, of which 3831 (27.0%) were seropositive for T. gondii antibody. The median follow-up time of the whole cohort was 22.5 (interquartile range 16.3, 24.5) years. A total of 5082 deaths were observed in this cohort, a mortality rate of 35.8%.
Cysticercosis is an infection caused by the larvae of the parasite Taenia solium. This infection occurs after a person swallows tapeworm eggs. The larvae get into tissues such as muscle and brain, and form cysts there (these are called cysticerci).
Which is exactly what happens to rodents infected with T. gondii—they lose their innate fear of cats and actually become attracted to them.
They found that both men and women infected with T. gondii were more extroverted and less conscientious than the infection-free participants. These changes are thought to result from the parasite's influence on brain chemicals, the scientists write in the May/June issue of the European Journal of Personality.
Almost all parasitoses involving the human brain can be associated with seizures and epilepsy, either by a diffuse encephalitis or encephalopathy, or by intracerebral location of the parasite [5].
Heat treatment like boiling water can inactivate T. gondii oocysts. Beef, lamb and veal roasts and steaks should be cooked to at least 63°C. Pork, ground meat and wild game should be cooked to 71°C before eating.
It's unlikely that your cat will give you toxoplasmosis. In fact, according to the Centers for Disease Control and Prevention, "people are more likely to get [toxoplasmosis] from eating raw meat or from gardening."
Ammonia, which is a toxic gas, can cause serious breathing issues and other problems. The ammonia can cause irritation of the bronchial membranes in your lungs, and lead to lots of coughing, as well as severe injury to the tissues in your trachea and lungs.
Interestingly, most people acquire toxoplasma by eating undercooked meat or contaminated produce. A pregnant woman can also become infected by inadvertently ingesting contaminated cat feces or inhaling litter dust while cleaning the litter box.
Healthy people (nonpregnant) Most healthy people recover from toxoplasmosis without treatment. Persons who are ill can be treated with a combination of drugs such as pyrimethamine and sulfadiazine, plus folinic acid.
As an obligately intracellular parasite, T. gondii must successfully enter a cell, replicate, and then exit by a process known as egress. Parasite egress results in the death of the host cell and is directly and indirectly (by the ensuing inflammatory response) responsible for major tissue damage (3).
This prevalence varies according to different continents, from 45% in North America to 74% in Africa. Toxoplasmosis is usually more prevalent, especially in moist, warm and low altitude regions [23]. This fact is associated with longer viability of T. gondii sporulated oocysts in a warm and humid areas [24].
Toxoplasmosis in wallabies has been shown to produce a number of ocular lesions. Unilateral or bilateral cataract formation, as well as various degrees of keratitis, uveitis, chorioretinitis, and endophthalmitis, have been observed among affected animals.
No, but they may make you less afraid of risk. There's a single-celled parasite called Toxoplasma gondii, and it can turn a normally risk-averse mouse into a bold, cat-seeking rodent. Cats that devour such mice can then pass the parasite onto humans.