The Texas Department of State Health Services (DSHS) and Cameron County Department of Health and Human Services have identified four additional cases of suspected locally transmitted Zika virus disease in Cameron County. The cases were part of the follow-up to the state's first case of Zika likely transmitted by a mosquito in Texas, announced on Nov. 28.
While the risk of exposure in Brownsville is thought to be low, in accordance with U.S. Centers for Disease Control and Prevention (CDC) guidance, DSHS recommends all pregnant Brownsville residents and those who travel there on or after Oct. 29 be tested for Zika. Residents and frequent travelers, who visit Brownsville on a daily or weekly basis, should get routine Zika testing once during the first trimester of pregnancy and once during the second trimester. Pregnant women with limited travel should discuss it with their doctor and be tested based on when the travel occurred. Because of the risk of sexual transmission, the same recommendations apply to women who have sex without a condom with a partner who is a Brownsville resident or traveler.
Health care professionals can find more detailed testing guidance in the CDC health alert. DSHS is also emphasizing its previous guidance to test pregnant women who have Zika symptoms or who travel to Mexico or other areas where mosquitoes are spreading Zika.
DSHS says the additional patients in Cameron County live in close proximity to the first case. Though the investigation is ongoing, the infections were likely acquired in that immediate area. The patients reported getting sick with Zika-like symptoms between Nov. 29 and Dec. 1 and were likely infected several days earlier, before mosquito control efforts intensified in that part of Brownsville. None are pregnant women. Testing of people living in an eight-block area around the homes of the identified cases continues but has yet to show any additional evidence of Zika transmission in the rest of that larger area.
"These cases were found through careful public health work and collaboration at the local, state, and federal levels," said John Hellerstedt, MD, DSHS commissioner, "and we’ll continue to follow through with the investigation and additional surveillance to identify other cases and other places experiencing local mosquito transmission of Zika. That information will be crucial to any future public health guidance."
DSHS says it's also important that health care professionals continue to be on the lookout for Zika and pursue testing pregnant women who have traveled to Mexico or other areas where Zika is spreading and testing anyone with symptoms compatible with Zika. More specific guidance for clinicians is available at www.texaszika.org.
"The combination of mosquito control and colder weather has decreased mosquito activity in Cameron County and greatly decreased the probability of more widespread mosquito transmission of Zika right now," Dr. Hellerstedt said. "However, winters are mild in southern Texas, and mosquito populations can rebound even during short periods of warmer weather. Whenever you see mosquito activity, protect yourself and your family from bites." You can do that by:
- Using Environmental Protection Agency-approved insect repellent.
- Using air conditioning or window and door screens that are in good repair to keep mosquitoes out of homes.
- Wearing long pants and long-sleeved shirts that cover exposed skin.
- Removing standing water in and around homes year-round, including water in trash cans, toys, tires, flower pots, and any other container that can hold water.
Prompted by the additional cases, the Texas Health and Human Services Commission is expanding the Medicaid benefit for mosquito repellent indefinitely for residents of Cameron County, as state health officials collect more information about the scope of transmission in Texas.
Zika virus is transmitted to people primarily through the bite of an infected mosquito, though it can also spread by sexual contact. The four most common symptoms are fever, itchy rash, joint pain, and conjunctivitis. While symptoms are usually minor, Zika can also cause severe birth defects, including microcephaly and other poor birth outcomes in some women infected during pregnancy.
DSHS recommends pregnant women avoid traveling to locations with sustained local Zika transmission, including Mexico. Pregnant women should also use condoms or avoid sexual contact with partners who have traveled to those areas. Travelers and the general public can find more information at TexasZika.org.
Action, Dec. 15, 2016