Malaria Cases Reported in Florida and Texas

June 27, 2023

The Centers for Disease Control and Prevention (CDC) issued a Health Alert Network health advisory on Monday in response to several confirmed cases of locally acquired malaria in Florida and Texas. The current cases have been identified as Plasmodium vivax malaria transmitted by the bite of infected Anopheles mosquitoes. The cases are the first instances of locally acquired mosquito-borne malaria in the United States since 2003.

In Florida, the Department of Health issued a statewide mosquito-borne illness advisory on Jun 26 after confirming four locally transmitted cases of malaria in Sarasota County. The advisory noted that effective treatment is readily available in the state and that all individuals have been treated and have recovered. It also recommended that residents be diligent in their personal mosquito-prevention efforts, including covering skin with clothing or appropriate repellent.

The Texas Department of State Health Services reported a single confirmed case of locally acquired malaria on June 23, in an individual who spent time working outdoors in Cameron County. The state agency said the individual had not recently traveled outside of the country or state. The state health advisory urged clinicians to routinely obtain a travel history if a symptomatic person spent time outdoors in an area with malaria activity and to promptly report suspected malaria cases.

Information for Blood Collectors

The Food and Drug Administration’s 2022 malaria guidance defines a malaria-endemic area as “any areas with malaria where CDC recommends anti-malarial chemoprophylaxis in travelers in the CDC Health Information for International Travel (commonly known as the Yellow Book) at the time the donor is screened.”

For donor screening purposes, FDA recommends use of the table in the “Malaria” chapter of the Yellow Book for CDC’s most current recommendations on anti-malarial chemoprophylaxis. The CDC has not made recommendations for the use of chemoprophylaxis in the affected areas.

Donor screening questions for travel to Florida or Texas have not been recommended at this time. However, AABB Standards, consistent with FDA regulations, require AABB-accredited facilities to confirm during the donor screening process that each donor is feeling healthy and well and is free of fever at the time of donation. Furthermore, donors are routinely instructed to notify the blood collection center if they develop symptoms or identify other risk of illness following their donation, providing an additional safety net to protect the blood supply.

AABB’s Transfusion Transmitted Diseases Committee is closely monitoring the reported cases. AABB will continue communications with the CDC and FDA and provide updates to AABB members in Weekly Report and on AABB’s Thursday Forum as new information emerges. Individuals with questions may contact