Descriptive epidemiology of acute febrile illness patients in Nigeria

Abstract

BACKGROUND: Undifferentiated acute febrile illness (AFI) is a diagnosis that elicits public health concern, as it may be the result of an undiagnosed case of a pathogen of epidemic potential. This study compares the hospital-based incidence and distribution of AFI-causing pathogens in Nigeria, utilizing polymerase chain reaction (PCR)-based surveillance.

METHODS: Patients presenting with AFI at tertiary hospitals in Federal Capital Territory (north-central) and Edo (south) were enrolled from August 2023 to September 2024. Patients were screened for 25 pathogens using the TaqMan Array Card multi-pathogen PCR. The analysis compared the occurrence and distribution of pathogens, alongside environmental and demographic factors.

RESULTS: One thousand two hundred febrile patients were enrolled, 600 (50%) from each site with 37.5% children. Twenty pathogens were detected in 694 (57.8%) enrollees. The three most commonly detected pathogens in this AFI population were Rickettsia spp. (n = 312, 26.0%), Plasmodium spp. (n = 293, 24.4%), and Lassa fever virus (n = 184. 15.3%). Other pathogens include Brucella spp. (n = 14), Neisseria meningitidis (n = 12), dengue virus (n = 10), o'nyong'nyong virus (n = 7), chikungunya virus (n = 6), Crimean-Congo hemorrhagic fever virus (n = 4), and 11 additional pathogens. No statistically significant differences were shown between the regions.

CONCLUSIONS: This epidemiologic study screening for the presence of 25 pathogens was instrumental in identifying pathogens of public health significance, including the first detection of four pathogens in humans in Nigeria. These findings suggest that there are likely other undetected cases of these pathogens, highlighting the need for continued surveillance to monitor and respond to emerging health threats.