Epidemiology of Plasmodium spp. Detection Among Acute Febrile Illness Patients in Two Regions of Nigeria.

Abstract

Malaria is a common cause of acute febrile illness (AFI) in Nigeria. Patients presenting with AFI at two tertiary hospitals were enrolled from August 2023 to September 2024. Specimens were screened for 25 pathogens using a multi-pathogen screening assay. Demographic, seasonal, clinical, and environmental associations with Plasmodium spp. detection via the assay are described and analyzed. An exploratory analysis of climatic predictors for percent positivity was conducted. Other pathogens detected, alongside Plasmodium spp., are reported. Plasmodium spp. was detected in 293 (24.4%) enrollees. Larger household size (crude odds ratio [COR] = 3.70, 95% confidence interval [CI] = 1.12-12.28), being a healthcare worker (COR = 3.39, CI = 1.22-9.41), children aged 11-14 (COR = 1.86, CI = 1.15-3.02), enrollment from FCT (COR = 1.30, CI = 1.00-1.69), and start of the dry season were associated with an increased risk for Plasmodium spp. detection. Coinfections were detected in 37.2% (n = 109) of the enrollees with Plasmodium spp. detected. Among these, nine biodefense pathogens, per the National Institute of Allergy and Infectious Diseases' list, were detected in 105 enrollees. No statistical significance among climatic predictors was found; however, a systematic directionality in minimum temperature effects across lag periods was observed. The magnitude of association varied by site with percent positivity in Edo State being more influenced by minimum temperature. These findings suggest the need for updated diagnostic options in healthcare facilities and expanded surveillance for emerging health threats. An expanded comparative analysis of differential climatic predictors for ecologically distinct regions may reveal insights relevant to prevention efforts.