Toxoplasma gondii. Most people who are infected with the parasite do not get sick. But the parasite can cause serious problems for people with weak immune systems and unborn babies." > Toxoplasma gondii. Most people who are infected with the parasite do not get sick. But the parasite can cause serious problems for people with weak immune systems and unborn babies." /> Toxoplasma gondii. Most people who are infected with the parasite do not get sick. But the parasite can cause serious problems for people with weak immune systems and unborn babies." />