G6PD and infection: Since these polymorphisms may not protect against initial infection but rather result in a slower parasite growth rate, as a consequence of a reduced parasite multiplication [26] or increased clearance of infected red blood cells [27], we hypothesize that the prevalence of sub-microscopic parasite carriage is higher in α+-thalassaemic and G6PD deficient individuals while that of high density parasitaemia is reduced.