A new look at the protection of hemoglobin AS and AC genotypes against plasmodium falciparum infection: a census tract approach.

A total of 4,097 randomly selected children under 5 years in Accra, Ghana were investigated for Hb type, malarial parasite species, and parasite density. Even though malarial infection rates in this metropolitan population were lower as compared to holoendemic areas, the differential survival of Hb S carriers was confirmed. In addition, similar but less pronounced survival effects were seen in Hb C heterozygotes.