Which of the following causes serious congenital disease from transplacental transmission?
A Toxoplasmosis
B Trichomoniasis
C Balantidiasis
D Giardiasis
The correct answer and explanation is:
The correct answer is A) Toxoplasmosis.
Toxoplasmosis is caused by the protozoan parasite Toxoplasma gondii. It is one of the most common parasitic infections worldwide and can be transmitted through ingestion of oocysts from contaminated food, water, soil, or by handling cat litter that contains infected feces. However, its significance in terms of congenital disease arises when a pregnant woman becomes infected with Toxoplasma gondii, as the parasite can cross the placenta and infect the fetus.
If a woman acquires the infection during pregnancy, especially in the first trimester, there is a higher risk that the fetus will develop severe congenital complications. The infection can lead to a range of birth defects, including microcephaly (a smaller-than-normal head), hydrocephalus (excess fluid in the brain), chorioretinitis (inflammation of the retina), and intellectual disabilities. Toxoplasmosis may also result in miscarriage, stillbirth, or preterm birth.
Although many people who are infected with Toxoplasma gondii show no symptoms, the infection can cause serious complications in immunocompromised individuals, such as those with HIV/AIDS, and in unborn babies when the infection occurs during pregnancy. Because of this, pregnant women are often advised to avoid handling cat litter or consuming undercooked meats that may harbor the parasite.
The other options—Trichomoniasis, Balantidiasis, and Giardiasis—are parasitic infections, but they are not commonly transmitted transplacentally or associated with serious congenital diseases in the way that toxoplasmosis is. Trichomoniasis, for instance, is an infection caused by Trichomonas vaginalis and is primarily transmitted through sexual contact, while Balantidiasis and Giardiasis are caused by protozoans that typically cause gastrointestinal issues and do not cross the placenta to affect the fetus.