A cross-sectional survey of malaria in asymptomatic and symptomatic individuals in an endemic area of Northcentral Nigeria.

Background objectives: The proportion of asymptomatic malaria is no doubt one of the factors determining the dynamics of its transmission and burden in endemic areas. This research focused on screening for Plasmodium parasitemia and analysing the relationship between proportions of malaria cases among asymptomatic and symptomatic persons in Lokoja, Northcentral Nigeria.

Methods: Cross-sectional survey and experimental designs were adopted. A semi-structured interview guide was used to collect data on socio-demography and clinical status of the participants. Blood samples were randomly collected from 328 consenting participants during high transmission season (April - October) of malaria within a three-year period (2018-2021), and screened for Plasmodium species by light microscopy (LM). Statistical analyses of related parameters were performed using the Statistical Package for the Social Sciences (SPSS) version 25 software.

Results: A total of 12.4% (25/202) and 85.7% (108/126) asymptomatic and symptomatic individuals were recorded respectively. There was no significant difference (p > 0.05) between the mean distributions of malaria cases among the asymptomatic and those of symptomatic persons. All cases identified were uncomplicated and falciparum-specific; and a 40.5% (133/328) prevalence of P. falciparum malaria with hyperparasitemia was observed in the area. The implications of these findings were discussed in relation to previous rates and other nearby endemic settings.

Interpretation conclusion: As a matter of success towards malaria elimination, a renewed call is made for regular monitoring of malaria prevalence using more efficient means of diagnosis and consideration of control strategies such as regular mass antimalarial administration, particularly targeting the often-neglected asymptomatic reservoir subset.