Malaria, 2010

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 2010, 48 malaria cases (0.9 per 100,000 population) were reported in Minnesota residents. This represents a 12% increase from the 43 cases reported in 2009 and a 33% increase from the median number of cases reported annually from 2000 to 2009 (median, 36 cases; range, 29 to 47). Of 46 cases in which the Plasmodium species was specified, 33 (72%) were identified with P. falciparum, 10 (22%) with P. vivax, 2 (4%) with P. malariae, and 1 (2%) with P. ovale. The median age of cases was 35 years (range, 2 to 66 years). Of 36 cases of known race, 31 (86%) were black, 4 (11%) were white, and 1 (3%) was Asian. Seventy-nine percent of cases resided in the metropolitan area, including 27 (56%) in Hennepin County. Of the 31 cases with known country of birth, 5 (16%) were born in the United States. Forty-one (85%) cases in 2010 likely acquired malaria in Africa. Four cases were likely acquired in Asia, 1 in South America, 1 in Central America, and 1 in Oceana. Sixteen countries were considered possible exposure locations for malarial infections, including Liberia (13 cases), Ghana (6 cases), Nigeria (5 cases), and Ethiopia (5 cases).

Updated Monday, 28-Nov-2011 14:10:34 CST