CDC adjusts Zika guide

Longer testing time for pregnant women

At-risk pregnant women who have Zika symptoms may undergo a key blood test as many as 14 days after they begin showing signs of the mosquito-borne virus, the Centers for Disease Control and Prevention told doctors Monday.

Earlier guidance from the CDC had suggested the blood test during the first seven days after symptoms begin. But new information indicates that some infected pregnant women can retain evidence of Zika in their blood beyond that window, the Atlanta-based agency said.

Its advisory applies to pregnant women with possible exposure to the virus, including those who recently visited outbreak-stricken countries. Sexual contact can spread Zika, too.

“Expanding the use of the Zika-specific test could provide more women with Zika virus infection a definite diagnosis and help direct medical evaluation and care,” the CDC said in a statement. Research has linked the virus to birth defects such as microcephaly, a neurological condition.

By July 14, 400 pregnant women in the continental United States had shown some laboratory evidence of possible Zika infection, according to the CDC. It wasn't clear how many of them might have been in Pennsylvania. None were in Allegheny County, said Kristen Mertz, a medical epidemiologist with the county.

Dr. Mertz said the revised

CDC guideline will probably lead to a small increase in overall Zika testing in pregnant women. A less-definitive antibody test, already in use, can help alert doctors to Zika as many as 12 weeks after a person’s exposure to the virus, clinicians said.

The state Department of Health said it anticipates no increases in overall Zika testing or in confirmed cases as a result of the modified federal guidance.

CDC tests have confirmed 51 Zika cases in Pennsylvania since early this year, all of them linked to travel in outbreak-affected areas abroad. Six of the cases were in Allegheny County, where more than 135 people have been approved to undergo Zika testing.

Also, the CDC now recommends a Zika blood test for all pregnant women with possible exposure to the virus, even if they show no symptoms, which can include a fever, joint pain or other mild ailments. Only about 20 percent of infected people develop such symptoms.

No mosquitoes are confirmed to have spread Zika on the U.S. mainland, but two cases reported last week in Florida may change that. Health authorities are looking into whether infected insects inside the state are likely responsible for sickening those people.