BACKGROUND: In hospital-based studies, alpha(+)-thalassemia has been found to protect against severe, life-threatening falciparum malaria. alpha(+)-Thalassemia does not seem to prevent infection or high parasite densities but rather limits progression to severe disease--in particular, severe malarial anemia. We assessed to what extent alpha(+)-thalassemia influences the association between mild, asymptomatic Plasmodium falciparum infection and hemoglobin concentration. METHODS: The study was based on 2 community-based surveys conducted among afebrile children (0.5-8 years old; n=801) in Kenya and Tanzania. RESULTS: Among children without inflammation (whole-blood C-reactive protein concentration <or=10 mg/L), P. falciparum infection was associated with only small reductions in hemoglobin concentration, and effects were similar across alpha-globin genotypes. By contrast, the reduction in hemoglobin concentration associated with P. falciparum infection accompanied by inflammation was larger and strongly depended on genotype (normal, -21.8 g/L; heterozygous, -16.7 g/L; and homozygous, -4.6 g/L). Relative to children with a normal genotype, this difference in effect was 5.1 g/L (95% confidence interval [CI], -1.0 to 11.1 g/L) for heterozygotes and 17.2 g/L (95% CI, 8.3 to 26.2 g/L) for homozygotes (estimates are adjusted for study site, age, height-for-age z score, and iron deficiency). CONCLUSIONS: alpha(+)-Thalassemia limits the decline in hemoglobin concentration that is associated with afebrile infections, particularly those that are accompanied by inflammation.
BACKGROUND: In hospital-based studies, alpha(+)-thalassemia has been found to protect against severe, life-threatening falciparum malaria. alpha(+)-Thalassemia does not seem to prevent infection or high parasite densities but rather limits progression to severe disease--in particular, severe malarial anemia. We assessed to what extent alpha(+)-thalassemia influences the association between mild, asymptomatic Plasmodium falciparum infection and hemoglobin concentration. METHODS: The study was based on 2 community-based surveys conducted among afebrile children (0.5-8 years old; n=801) in Kenya and Tanzania. RESULTS: Among children without inflammation (whole-blood C-reactive protein concentration <or=10 mg/L), P. falciparum infection was associated with only small reductions in hemoglobin concentration, and effects were similar across alpha-globin genotypes. By contrast, the reduction in hemoglobin concentration associated with P. falciparum infection accompanied by inflammation was larger and strongly depended on genotype (normal, -21.8 g/L; heterozygous, -16.7 g/L; and homozygous, -4.6 g/L). Relative to children with a normal genotype, this difference in effect was 5.1 g/L (95% confidence interval [CI], -1.0 to 11.1 g/L) for heterozygotes and 17.2 g/L (95% CI, 8.3 to 26.2 g/L) for homozygotes (estimates are adjusted for study site, age, height-for-age z score, and iron deficiency). CONCLUSIONS: alpha(+)-Thalassemia limits the decline in hemoglobin concentration that is associated with afebrile infections, particularly those that are accompanied by inflammation.
Authors: Erasto V Mbugi; Marjolein Meijerink; Jacobien Veenemans; Prescilla V Jeurink; Matthew McCall; Raimos M Olomi; John F Shao; Hans Verhoef; Huub Fj Savelkoul Journal: Malar J Date: 2010-05-17 Impact factor: 2.979
Authors: Michael A Krause; Seidina A S Diakite; Tatiana M Lopera-Mesa; Chanaki Amaratunga; Takayuki Arie; Karim Traore; Saibou Doumbia; Drissa Konate; Jeffrey R Keefer; Mahamadou Diakite; Rick M Fairhurst Journal: PLoS One Date: 2012-05-18 Impact factor: 3.240
Authors: Roger C K Tine; Magatte Ndiaye; Helle Holm Hansson; Cheikh T Ndour; Babacar Faye; Michael Alifrangis; K Sylla; Jean L Ndiaye; Pascal Magnussen; Ib C Bygbjerg; Oumar Gaye Journal: BMC Res Notes Date: 2012-10-11
Authors: Eric M Foote; Kevin M Sullivan; Laird J Ruth; Jared Oremo; Ibrahim Sadumah; Thomas N Williams; Parminder S Suchdev Journal: Am J Trop Med Hyg Date: 2013-02-04 Impact factor: 2.345