[Morbidity and severity of malaria attacks in carriers of sickle-cell trait].

The authors made a survey in a permanent high Plasmodium falciparum transmission area to compare frequency and severity of malaria attacks in children belonging to different haemoglobin types before 15 years; 291 young out-patients of the local infirmary and 467 outpatients of the hospital were examined. Diagnosis of malaria was inferred from clinical and parasitological criteria and subsequent evolution of the disease. Pathogenic threshold of parasitaemia was similar in all haemoglobin type groups of children and was about 3,000 parasite-infected red cells per mm3. Malaria was diagnosed more often among HbAA patients, than among other patients. Mortality rate in AA haemoglobin children was higher than 3% whereas in sickle cell trait carriers no death could be certainly attributed to malaria. The S gene rate was significantly weaker (p < 0.05) in subjects attacked by Malaria (5%) than in all other groups of children. In the endemic malaria areas the susceptibility of S gene carriers appears to be lesser than in AA haemoglobin children and could explain the paradoxically lower rate of mortality in this group.