A profile of sickle cell disease in Nigeria.
Nigeria has a population of 112 million with an annual growth rate of 3.2%. About 25% of adults throughout the country have the sickle cell trait, AS, while the Hb C trait is largely confined to the Yoruba people of southwestern Nigeria in whom it occurs in about 6%. Other variant hemoglobins including beta thalassemia are rare, but alpha thalassemia occurs in 39% (32% with 3 alpha-globin genes; 7% with 2 alpha-globin genes). Of a total of 5.4 million expected live births in 1988, about 90,000 will have SCD and 1.1 million the trait, AS. The clinical phenotype of sickle cell anemia is severe with manifestations occurring very early in childhood and mean Hb level 7.6 g/dl with HbF 5.9%. A very high infant mortality due to infections occurs especially in rural areas. Gallstones, leg ulcerations, and stroke appear less common than in American sicklers, and aplastic crises have not been described. Poor availability of resources to the public health and welfare sectors and economic inflation are severely curtailing access to appropriate medical and social services. This situation is frustrating to the families of a growing number of surviving patients in urban or middle to upper income groups. Efforts to create more awareness of SCD are paradoxically increasing frustration and stigmatization in the absence of a commensurate improvement of services. Any measures aimed at enhancing the sensitization of health professionals, policy makers, and resource allocators to the pertinent issues in the control of SCD would seem to be at this stage an important step in the right direction.