Toxoplasmosis is best described as which of the following?

• A. Toxoplasmosis is a parasite that can cause a serious blood infection and is found in the waste of cats.
• B. Listeria is a fungus that causes skin infections.
• C. Lyme disease is a virus transmitted by ticks.
• D. Zika virus is a parasite transmitted by insects.

Answer: (A)

Toxoplasmosis is a parasitic infection caused by a protozoan called Toxoplasma gondii. Cats are a primary source because they shed the parasite in their feces; contact with cat litter or soil contaminated by infected feces can lead to human infection. This is why describing toxoplasmosis as a parasite linked to cat waste fits best among the options. The other choices describe different organisms or infectious agents: Listeria is a bacterium, not a fungus; Lyme disease is caused by a bacterium transmitted by ticks, not a virus; Zika is a virus spread by mosquitoes, not a parasite.