Locally Acquired Cases of Malaria in Florida, Texas, and Maryland

CDC is collaborating with three state health departments on an investigation of seven locally acquired cases of Plasmodium vivax (P. vivax) malaria in Sarasota County, FL, one case of P.vivax in Cameron County, TX, and one case of P. falciparum malaria in a Maryland resident who lives in the National Capital Region. There is no evidence to suggest that the cases in the three states are related. All patients were promptly treated at area hospitals and are recovering.

Most malaria cases diagnosed in the United States are imported, usually by persons who travel to countries where malaria is endemic (regularly occurring). However, locally acquired mosquito-transmitted malaria cases can occur, as Anopheles mosquito vectors exist throughout the United States. In 2003 there were 8 cases of locally acquired P. vivax malaria identified in Palm Beach County, FL.

Florida, Texas, and Maryland have been engaging in additional surveillance activities and mitigation efforts to reduce the possibility of additional local transmission. CDC is coordinating with, and providing technical assistance to, state and local officials.

The risk of locally acquired malaria is very low in the United States. Malaria is primarily spread by mosquitoes. If you have traveled to an area where malaria occurs and develop fever, chills, headache, body aches, and fatigue, seek medical care urgently and tell your healthcare provider that you have traveled.

To prevent mosquito bites, use Environmental Protection Agency (EPA)-registered insect repellants, wear loose-fitted long-sleeved shirts and pants, and use screens on windows and doors.
In addition to routinely considering malaria in febrile patients with a history of travel to areas where malaria is transmitted, the diagnosis of malaria should also be considered in any person with fever of unknown origin regardless of travel history.

See the CDC malaria website for additional health information about malaria including prevention of mosquito bites and drugs for malaria prevention.

Read the Health Alert Network Health Advisory: Locally Acquired Malaria Cases Identified in the United States.