6 Harris County women report new Zika infections

Those who tested positive able to deliver babies with no clear signs of microcephaly

Six pregnant women in Harris County have tested positive for Zika, the first cases of the mosquito-borne disease to be reported locally in 2017.

All of the women have since delivered their babies, none with the abnormally small head that characterizes the worst form of the disease when the virus is passed on by the mother. The women, who contracted the virus south of the border, were tested because of their risky travel histories, not because they were experiencing Zika symptoms.

“All indications we have are that the babies are healthy,” said Dr. Ann Barnes, chief medical officer at Legacy Community Health, a Southeast Texas network of clinics where the expectant mothers had gone for appointments and to have their blood drawn.

Babies born to mothers infected with Zika can appear healthy at birth, only to have neurological problems become apparent later. Dr. Peter Hotez, a Baylor College Medicine infectious disease specialist and expert on Zika, said he hopes all of the babies have been referred to pediatric neurologists for a work-up, emphasizing that the full impact of Zika on the nervous system is still being determined.

Barnes said the cases show pregnant women should remain vigilant about Zika, even though the disease threat appears lower this year than it did last year in the U.S. Gulf Coast, when public health officials sounded the alarm that imported cases could trigger a local outbreak. New reports have shown decreased viral activity in the Caribbean, Central America and most of South America, all hotbeds of activity last year, and the World Health Organization now says the virus is no longer a global health emergency.

The six Harris County cases were confirmed in late May by the

Centers for Disease Control and Prevention and announced Thursday by Legacy. Three of the women had their blood drawn in late 2016, and three had it drawn in 2017, between January and April. Legacy sent the blood to the Texas Department of Health for preliminary testing before it went to the CDC.

Zika emerged as a global threat in 2007. It started spreading extensively in 2015 and 2016, reaching at least 80 countries and territories, mostly in the Southern Hemisphere. The only reported cases in Harris County have involved people acquiring the virus while traveling to regions that had outbreaks. Seventy-five such cases were imported to Harris County in 2016.

Microcephaly research

Local transmission of the virus occurred in Florida last summer and in South Texas in November and December.

Zika is not considered fatal, but it has been linked to thousands of cases of microcephaly, in which the infected mother’s baby is born with an abnormally small head and brain. The condition can result in developmental delays, intellectual disability and hearing, vision and feeding problems.

But recent research has also found the babies affected by the virus can experience developmental delays even though they do not have microcephaly. The finding suggests a baby whose head looks normal may in fact suffer from serious brain deficits that parents and doctors may not notice until they get older.

The Harris County mothers delivered the babies at hospitals. Barnes said Legacy’s information that the babies appear healthy is based on predelivery imaging and postdelivery updates.

Conflicting data exists about the level of birth defects caused by Zika. One Brazilian study reported defects in 42 percent of such babies while another in the U.S. reported defects occurred in just 5 percent, 15 if the mother was infected during the first trimester of pregnancy.

Zika and pregnancy

Texas’ health department has received 206 reports of pregnancy-related Zika infections, most not involving women experiencing symptoms, since the virus’ onset in the state in late 2015. Ninety-two of those have been reported in 2017.

Overall, Zika disease has started slowly this year, with only 14 people having been reported to have been infected and experiencing symptoms.

An exact breakdown was not available, but Mexico, Guatemala and El Salvador were the countries to which the Harris County women traveled while pregnant. It is unclear what the level of Zika activity was in those countries when they were there, but Barnes and Hotez said their experience shows the virus is still being transmitted and can be spread, despite the current lesser threat.

“Patient education in Harris County must continue through this year’s mosquito season,” Barnes said in a statement put out by Legacy. “Prevention must still be the key message coming from public health officials and health care providers.”

In the U.S., CDC-issued travel alerts are still in effect for Cameron County in South Texas and MiamiDade County in Florida.