Three types of parasites can cause disease in humans. They are protozoa, carried by mosquitos, helminths, such as roundworm, and ectoparasites, for instance lice and bed bugs. Parasites are organisms ...

Parasites live in other host organisms and depend on them for survival. Parasites that can affect humans include ticks, lice, and hookworms. Symptoms of a parasite infection in humans can vary widely.

A common parasite long thought to lie dormant is actually much more active and complex. Researchers found that Toxoplasma gondii cysts contain multiple parasite subtypes, not just one sleeping form.

People typically become infected with toxoplasmosis by eating undercooked meat or through contact with contaminated soil or cat feces. Once inside the body, the parasite is known for its ability to ...