Question

What protozoan parasite is acquired by the oral route, but once ingested can readily cross the placenta causing an infection in the fetus that can result in a number of congenital defects?

1) Giardia intestinalis
2) Toxoplasma gondii
3) Cryptosporidium parvum
4) Cyclospora cayetanensis

Answer 1

Toxoplasma gondii is the protozoan parasite that can be acquired orally and cross the placenta, causing toxoplasmosis in the fetus, which can lead to congenital defects.

Step-by-step explanation:

The protozoan parasite that is acquired by the oral route and can cross the placenta, causing an infection in the fetus that can result in a number of congenital defects, is Toxoplasma gondii. This organism causes toxoplasmosis and is typically transmitted from infected cat feces, unwashed fruit and vegetables, or undercooked meat. Pregnant women need to exercise caution as toxoplasmosis during pregnancy can lead to serious birth defects.

While other mentioned protozoans such as Giardia intestinalis, Cryptosporidium parvum, and Cyclospora cayetanensis are also responsible for gastrointestinal infections, only Toxoplasma gondii is known for its teratogenic effects on the fetus when transmitted from the mother.