Malaria is a febrile illness caused by several protozoan species in the genus Plasmodium. The parasite is transmitted to humans by bites from infected Anopheles genus mosquitoes. The risk of malarial infection is highest in the tropical and sub-tropical regions of the world. Although local transmission of malaria frequently occurred in Minnesota over 100 years ago, all of the cases reported in Minnesota residents since that time likely have been imported infections acquired abroad.
In 2012, 58 malaria cases (1.1 per 100,000 population) were reported in Minnesota residents, above the 2000 to 2012 annual median of 41 cases (range, 29 to 58). Forty (69%) cases were identified with P. falciparum, 8 (14%) with P. vivax, 3 (5%) with P. ovale, 2 (3%) with P. malariae, and 1 (2%) with mixed Plasmodium species infections; infections with unidentified Plasmodium species were detected in 4 (7%) cases. The median age of cases was 34 years (range, 3 to 77 years). Of 41 cases of known race, 37 (90%) were black, 3 (7%) were Asian, and 1 (2%) was white. Eighty-one percent of cases resided in the metropolitan area, including 44 (76%) in Hennepin or Ramsey Counties. Of the 38 cases with known country of birth, 1 (3%) was born in the United States. Forty-eight (83%) cases in 2012 likely acquired malaria in Africa and 7 (12%) cases were likely acquired in Asia. Fifteen countries were considered possible exposure locations for malaria infections, including Liberia (19), Nigeria (5), Ethiopia (5), Kenya (5), and India (5).
- For up to date information see>> Malaria
- Full issue>> Annual Summary of Communicable Diseases Reported to the Minnesota Department of Health, 2012