CDC Investigates U.S. Malaria Cases

CDC is collaborating with state and local health departments to investigate locally acquired malaria cases (Plasmodium vivax or P. vivax ). To date, Florida has identified seven cases, and Texas has detected one, with illnesses identified between May and July. There is no evidence to suggest the cases in the two states are related. The risk to the public for locally acquired mosquito-transmitted malaria remains very low. However, the Anopheles species of mosquito that transmits malaria is present across the United States, and areas with this type of mosquito coupled with higher numbers of imported malaria cases are at higher risk for local malaria transmission.

While severe complications and death can occur with P. vivax infections, the frequency of these outcomes is low. However, without proper treatment, relapses can occur months or years later. The most effective way to prevent malaria is to prevent mosquito bites and ensure early diagnosis and treatment of imported cases.

CDC continues to educate clinicians on the diagnosis and treatment of malaria. CDC’s July 20 Clinician Outreach and Community Activity call, Review of Malaria Diagnosis and Treatment in the United States, provided pertinent clinical information.

Public health officials who are concerned about potential cases of locally acquired malaria should contact CDC’s Malaria Branch or call 770-488-7788 during regular business hours. Contact CDC’s Emergency Operations Center or call 770-488-7100 outside of regular business hours for assistance with recommendations and testing.

For more information on malaria, visit CDC’s Malaria Is a Serious Disease webpage.