A resident of Brownsville, TX, has been diagnosed with Zika virus infection without any other known risk factors, meaning it may be the first local transmission of the virus by mosquitos in the state, the Centers for Disease Control and Prevention announced yesterday. State and local officials are responding with a community-wide search for additional cases, as recommended in CDC’s Zika interim response plan, and working with CDC to increase surveillance and vector control activities in the area. Residents, especially pregnant women, should take steps to protect themselves from mosquito bites, the agency said. Zika infection during pregnancy can cause microcephaly and other severe brain defects in fetuses and infants. CDC recently released a tool to help health care providers apply its recommendations for Zika virus testing, interpretation of results and clinical management for pregnant women with possible exposure to the virus. As of Nov. 23, CDC’s ArboNET has reported 182 locally acquired cases of the mosquito-borne virus in Florida and more than 4,200 travel-associated cases in the continental United States and Hawaii.