BROWNSVILLE, Texas (CN) – A Brownsville woman who has not traveled to any Zika-virus hotspots tested positive last week, Texas health officials said Monday, marking the first suspected local transmission in Texas.
Lab tests last week found the virus in the woman’s urine, not her blood, which indicates the virus can no longer be spread from her by a mosquito, the Texas Department of State Health Services said in a statement.
“There are no other cases of suspected local transmission at this time, but health officials continue to conduct disease surveillance activities as part of the state’s ongoing Zika response,” according to the agency.
Though more than 250 people in Texas have tested positive for the virus that is spread by the Aedes aegypti mosquito, all of them had traveled to areas where it is actively spreading, according to the agency.
Brownsville is just across the border from Matamoros, Mexico, where it’s possible the virus is being passed locally, but the woman said she had not recently traveled to Mexico.
“We knew it was only a matter of time before we saw a Zika case spread by a mosquito in Texas. We still don’t believe the virus will become widespread in Texas, but there could be more cases, so people need to protect themselves from mosquito bites, especially in parts of the state that stay relatively warm in the fall and winter,” Texas DSHS Commissioner Dr. John Hellerstedt said in a statement.
Florida is the only other U.S. state where the virus is known to have been spread locally, and aggressive pesticide-spraying there has apparently worked.
Florida and federal health officials declared on Nov. 22 that two areas of Miami Beach are free of local Zika transmission, meaning that no one has contracted the virus there in the past 45 days.
The Zika virus has swept across the Western Hemisphere since Brazil reported its first cases in March 2015 and scientists have confirmed it is responsible for a spike in babies born with congenital defects, while warning pregnant women not to travel to areas where mosquitoes carry the virus.
Recent studies show Zika can also cause latent birth defects in babies who were apparently healthy at birth.
The news of the suspected local transmission is especially worrisome for South Texas residents because the region’s mild winters mean Aedes aegypti mosquitoes can be active into January.
The state health department said further testing will try to pinpoint how and where the woman, whose name was not disclosed, contracted the virus.
The city of Brownsville is spraying pesticides by the woman’s home and health workers are going door-to-door in the area, collecting voluntary urine samples of residents and looking for any small water-filled containers that are the preferred habitat of Aedes aegypti mosquitoes, which can also spread dengue fever, chikungunya and yellow fever.
Dr. Peter Hotez, director of Texas Children Hospital’s Center for Vaccine Development and a molecular biology and pediatrics professor at Baylor College of Medicine, has been warning Texans about the potentially devastating consequences of the Zika virus since early this year.
He says impoverished people are more at peril for contracting the virus because they are more likely to be living in a home without air conditioning and window screens to keep the mosquitoes out.
Scientists say most adults don’t show symptoms of the virus and those that do usually experience only mild flu-like symptoms, which means the virus could be more widespread than documented.
“We won’t know how widespread the virus really was until babies with microcephaly begin being born, probably in the spring. And I expect it to return next year,” Hotez told the New York Times.