Healthy adults easily fight the infection. But a pregnant woman who becomes infected has up to a 50 percent chance of transmitting it to her fetus, say the National Institutes of Health. Pregnant women with weak immune systems who were carriers also risk passing the infection.
According to the Center for the Evaluation of Risks to Human Reproduction, two in 1,000 babies are infected. The March of Dimes says 10 percent show symptoms at birth; 55 to 85 percent develop symptoms later.
Because the infection often goes unnoticed, experts say pregnant women should be tested. "This is a preventable, treatable disease," says study co-author Dr. Rima McLeod of the University of Chicago Hospitals.
The study, published in the American Journal of Obstetrics and Gynecology, followed 131 children. Researchers found more than half the at-risk mothers couldn’t be identified by routine exams. A blood test could have identified the rest, they concluded, but only 8 percent of the mothers were given blood tests. Insurance ususally covers screenings. The disease is treated with antibiotics.
People contract the disease by ingesting parasite eggs contained in cat feces. That can happen when people touch kitty litter or contaminated soil or eat unwashed vegetables. The parasite is also passed through undercooked, infected meat. The American College of Obstetrics and Gynecology recommends routine screening only in women with HIV and possibly for cat owners.
Fiona Forward, a New York mother of one girl in the study, encourages pregnant friends to get screened. When Forward learned she was infected, she started taking medication. Her daughter, now 5, was born with 40 brain calcifications. After a year of medication, she has slight vision problems and three calcifications. "We’re very lucky we had a good result," Forward says.
Dr. Laura Riley, of the American College of Obstetrics and Gynecology, warns that screening early in pregnancy results in many false positives, which can cause anxiety and may lead women to terminate a pregnancy for no reason.
Paige Fumo Fox