Plasmodium falciparum parasite density in symptomatic and asymptomatic malaria among residents of Abuja, Nigeria

Abstract

Plasmodium falciparum is prevalent in sub-Saharan Africa and constitutes the greatest public health burden relative to the four species of the parasite that infect humans. World Health Organization (WHO) uses parasite density to describe malaria severity, where 250,000 parasites/µL and 500 parasites/µL are set as the cutoff points for hyperparasitemia in low and high P. falciparum endemic regions, respectively. This classification may not be universal as different factors influence parasite density. This study evaluated the parasite densities in symptomatic and asymptomatic persons in Abuja with a view to understanding host tolerance to P. falciparum in an endemic condition. This study was carried out using 246 blood samples each from symptomatic and asymptomatic volunteers, from two area councils in Abuja following WHO standard methods for Malaria microscopy. The result revealed symptomatic and asymptomatic groups with median axillary temperature that differed significantly (P = 0.012), parasite densities both lower that WHO cut off mark, and did not differ significantly between symptomatic and asymptomatic, among different age groups and catchment areas (P > 0.05). Parasite density does not differ in symptomatic and asymptomatic subjects in P. falciparum, which is endemic in Abuja and is lower than WHO set values.