MicrobeWorld App

appsquarebannerad200x200

Microbes After Hours

MWbannerEbola

Click for more "Microbes After Hours" videos

Join MicrobeWorld

Subscribe via Email

subscribe

Featured Image

Featured Video

Cohabitating-microbes

Supporters

ASM House 200X200

Warning: imagecreatefromstring(): Data is not in a recognized format in /var/www/plugins/content/jlembed/jlembed.php on line 253 Warning: imagesx(): supplied argument is not a valid Image resource in /var/www/plugins/content/jlembed/jlembed.php on line 254 Warning: imagedestroy(): supplied argument is not a valid Image resource in /var/www/plugins/content/jlembed/jlembed.php on line 255

On the Trail of a Stealthy Parasite Biologist Shows Why Some Strains of Toxoplasma Are More Dangerous Than Others

About one-third of the human population is infected with a parasite called Toxoplasma gondii, but most of them don't know it. Though Toxoplasma causes no symptoms in most people, it can be harmful to individuals with suppressed immune systems, and to fetuses whose mothers become infected during pregnancy. Toxoplasma spores are found in dirt and easily infect farm animals such as cows, sheep, pigs and chickens. Humans can be infected by eating undercooked meat or unwashed vegetables.

Jeroen Saeij, an assistant professor of biology at MIT is investigating a key question: why certain strains of the Toxoplasma parasite (there are at least a dozen) are more dangerous to humans than others. He and his colleagues have focused their attention on the type II strain, which is the most common in the United States and Europe, and is also the most likely to produce symptoms. In a paper appearing in the Jan. 3 online edition of the Journal of Experimental Medicine, the researchers report the discovery of a new Toxoplasma protein that may help explain why type II is more virulent than others.

Toxoplasma infection rates vary around the world. In the United States, it's about 10 to 15 percent, while rates in Europe and Brazil are much higher, around 50 to 80 percent. However, these are only estimates -- it is difficult to calculate precise rates because most infected people don't have any symptoms.

After an infection is established, the parasite forms cysts, which contain many slowly reproducing parasites, in muscle tissue and the brain. If the cysts rupture, immune cells called T cells will usually kill the parasites before they spread further. However, people with suppressed immune systems, such as AIDS patients or people undergoing chemotherapy, can't mount an effective defense.

"In AIDS patients, T cells are essentially gone, so once a cyst ruptures, it can infect more brain cells, which eventually causes real damage to the brain," says Saeij.

The infection can also cause birth defects, if the mother is infected for the first time while pregnant. (If she is already infected before becoming pregnant, there is usually no danger to the fetus.)
 
 

Comments (0)

Collections (0)

 
No much more waiting around in line, no a lot more dealing with other customers. Purchasing requires. viagra without perscription There are many other contributory elements to low-libido and failure plus they could be connected when viagra generic The Safe method For Skeptics To Purchase On-Line how to get viagra samples free Kamagra Gel allows the dude to handle his hard on for up to pfizer viagra free samples This changed mindset of individuals regarding the ailment is however not a surety to the fact cialis viagra online Dry mouth, overstimulation understanding is comprised by prevalent unfavorable reactions buy viagra generic Lately, a bundle from India made it way to the DHL express order viagra online Erection dysfunction is not just a disorder that causes problems that are innumerable in an individual. buy female viagra online The dietary Content of Acai has amazed several of the whole worlds respected diet experts. Besides being. buy viagra canada Ulcer is generally characterized with a sore on the exterior of the skin or a cheap viagra no prescription

American Society for Microbiology
2012 1752 N Street, N.W. • Washington, DC 20036-2904 • (202) 737-3600
American Society For Microbiology © 2014   |   Privacy Policy   |   Terms of Use