Spleen enlargement and genetic diversity of Plasmodium falciparum infection in two ethnic groups with different malaria susceptibility in Mali, West Africa

• The high resistance to malaria in the nomadic Fulani population needs further understanding. The ability to cope with multiclonal Plasmodium falciparum infections was assessed in a cross-sectional survey in the Fulani and the Dogon, their sympatric ethnic group in Mali. The Fulani had lower parasite prevalence and densities and more prominent spleen enlargement. Spleen rates in children aged 2–9 years were 75% in the Fulani and 44% in the Dogon (P < 0.001). There was no difference in number of P. falciparum genotypes, defined by merozoite surface protein 2 polymorphism, with mean values of 2.25 and 2.11 (P = 0.503) in the Dogon and Fulani, respectively. Spleen rate increased with parasite prevalence, density and number of co-infecting clones in asymptomatic Dogon. Moreover, splenomegaly was increased in individuals with clinical malaria in the Dogon, odds ratio 3.67 (95% CI 1.65–8.15, P = 0.003), but not found in the Fulani, 1.36 (95% CI 0.53–3.48, P = 0.633). The more susceptible Dogon population thus appear to respond with pronounced spleen enlargement to asymptomatic multiclonal infections and acute disease whereas the Fulani have generally enlarged spleens already functional for protection. The results emphasize the importance of spleen function in protective immunity to the polymorphic malaria parasite.

Ämnesord

MEDICIN OCH HÄLSOVETENSKAP  -- Klinisk medicin -- Infektionsmedicin (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Clinical Medicine -- Infectious Medicine (hsv//eng)

Nyckelord

Adolescent

Adult

Aged

Animals

Antigens; Protozoan/genetics

Child

Child; Preschool

Cross-Cultural Comparison

Cross-Sectional Studies

Disease Susceptibility

Genetic Variation/genetics

Humans

Infant

Infant; Newborn

Malaria; Falciparum/*ethnology/parasitology

Mali

Middle Aged

Plasmodium falciparum/*genetics

Protozoan Proteins/genetics

Splenomegaly/*ethnology/parasitology

MEDICINE

MEDICIN

Infectious diseases

Infektionssjukdomar

Infektionssjukdomar

Infectious Diseases

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)