Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Toxoplasmosis ?
    ### Response:
    Toxoplasmosis is a disease caused by the parasite Toxoplasma gondii. More than 60 million people in the U.S. have the parasite. Most of them don't get sick. But the parasite causes serious problems for some people. These include people with weak immune systems and babies whose mothers become infected for the first time during pregnancy.
    