CDC Updates Guidance for Investigating Locally Acquired Malaria in the United States

CDC updated its operational guidance for investigating suspected locally acquired mosquito-transmitted malaria in the United States following 10 autochthonous cases reported across four states in 2023 after two decades without documented local transmission.

The guidance emphasizes that, although malaria was eliminated in the 1950s, widespread presence of Anopheles mosquitoes and increasing imported cases sustain reintroduction risk. It outlines enhanced investigations for cases without travel history, requiring coordinated epidemiologic, entomologic, and laboratory response across local, state, and federal levels.

Public health action includes rapid diagnostic testing, mandatory reporting, standardized case classification, and parallel field and molecular investigations to assess and interrupt potential local transmission. Read more in CDC’s MMWR here.