Today the Texas Department of State Health Services (TDSHS) reported a case of locally acquired Zika in Cameron County, a first for a state that has been on high alert for local transmission since the beginning of October and the first local US case outside of Florida.
"We knew it was only a matter of time before we saw a Zika case spread by a mosquito in Texas," John Hellerstedt, MD, TDSHS commissioner, said in a press release. "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."
So far, one patient, a non-pregnant woman with no recent travel or sexual transmission risks, has been diagnosed as having locally acquired Zika. The disease was confirmed through urine analysis late last week. According to the US Centers for Disease Control and Prevention (CDC) the patient lives in Brownsville, Texas.
The Zika virus, which goes undetected in 80% of patients, is transmitted by Aedes species of mosquito. Both Ae aegypti and Ae albopictus are found in Brownsville.
Heightened surveillance in Brownsville
The CDC said it would be aiding TDSHS about continued, heightened surveillance of the Rio Grande Valley, including conducting an environmental assessment at the patient's home and trapping and testing mosquitoes across the region. According to the TDSHS, Brownsville has recently sprayed for mosquitoes in the area and will continue to do so.
"Even though it is late in the mosquito season, mosquitoes can spread Zika in some areas of the country," said CDC Director Tom Frieden, MD, MPH, in a media release. "Texas is doing the right thing by increasing local surveillance and trapping and testing mosquitoes in the Brownsville area."
Beginning this evening, health workers from TDSHS will be going door to door in the patient's neighborhood to educate people on how to remove standing water and protect themselves against Zika. They will also collect voluntary urine samples to determine if there are other local infections.
As of Nov 23, the CDC said 4,444 cases of Zika have reported in the continental United States and Hawaii; 182 of these were the result of local spread by mosquitoes in Florida. Those numbers do not include the Brownsville case.
Both the CDC and the TDSHS said pregnant women in the region need to take extra precautions, including using insecticide spray and wearing long-sleeved clothing.
Two new cases in Florida
Last week the Florida Department of Health (Florida Health) reported two new locally acquired Zika cases, one in Broward County and the other in Miami-Dade County. Florida Health is still investigating where transmission occurred, but it said active transmission is still taking place in Miami Beach and Little River only.
See also:
Nov 28 TDSHS news release
Nov 28 CDC press release
Oct 4 CIDRAP News story on enhanced surveillance in Rio Grande Valley
Nov 23 Florida Health update
