In 1975, 447 cases of malaria were reported in the United States. This represents a 38.4% increase compared with the 323 cases reported for a similar period in 1974, and was primarily related to a substantial increase in the number of malaria cases in civilians. Only 17 reported cases (4% of all cases reported in the United States) were in military personnel in 1975, the smallest number since 1959. As in previous years, imported Plasmodium vivax infections were more common than P_. falciparum (61.3% versus 24.4%).

In 2 instances, infection was acquired in the United States: in 1 case infection was induced by transfusion and in 1 the disease was transmitted congenitally. Two deaths attributed to malaria were reported in 1975, compared with 6 in 1974. Both deaths occurred in civilians; 1 patient was infected with P. falciparum acquired in Cambodia, and the other had acquired £. malariae malaria by blood transfusion. The P. falciparum malaria death-to-case ratio of 0.9% was lower than that in 1974 (6.4%), but did not differ significantly from the 10-year (1965-1974) ratio of 1.6%.

Stephen B. Thacker CDC Library collection

United States