The Health Department is recommending expanded Zika testing for pregnant women in six south Texas counties.
The health alert is for Cameron, Hidalgo, Starr, Webb, Willacy and Zapata counties.
Pregnant women are being urged to get tested during their first and second trimesters.
Last year, there were six cases of mosquitoes transmitting the virus to people in Brownsville, Texas.
Zika is transmitted to people from the bite of an infected mosquito. Symptoms are usually minor but can cause severe birth defects in babies of some women infected during pregnancy.