Health Ministry Extends Guidelines for Zika Testing

Every pregnant woman who could have been exposed must now be tested.

A mother holds her daughter, an 8-month-old with microcephaly, after a bath on Christmas Eve in Areia, Brazil, December 24, 2016.

The Health Ministry has broadened its testing guidelines for the Zika virus this week. Starting now, every pregnant woman who could have been exposed to the virus in one of the countries where Zika is widespread will be tested, even if she doesn't exhibit any symptoms. Women who were potentially exposed up to eight weeks before becoming pregnant will also be tested.

Prof. Eli Schwartz, director of the Center for Travel Medicine and Tropical Diseases at the Sheba Medical Center at Tel Hashomer, explained that as physicians and researchers delve deeper into Zika, they gain new insights into how the virus behaves.

“In recent months we learned that even in cases where the pregnant woman was infected but displayed no symptoms, there were cases of fetal infection,” Schwartz said, adding that the virus’ incubation period can vary depending on the method of infection. “When infected by a mosquito bite, the virus remains in the blood for two to three weeks, while infection through sexual intercourse carries longer incubation periods of up to a month in vaginal fluids and up to six months in semen,” he said.

In addition to pregnant women, the ministry advises the testing of men and women who could have been exposed and exhibit symptoms; babies born to women who suspect they are ill and were potentially exposed to the virus; and any person who could have been exposed in one of the affected countries, mostly in Central and South America, complaining of neurological problems of unclear origin.

Although lab tests are the only way to detect the virus, the ministry stressed that negative results don't completely rule out infection. For this reason, the ministry calls on pregnant women at risk to have three fetal brain scans, the first at 16 weeks of pregnancy, no matter what their lab results show.