High rate of unrecognized dengue virus infection in parts of the rainforest region of Nigeria

• Prevalence of 23.4% recent dengue virus exposure was found in 8 months.
• Highest monthly prevalence of 40% dengue exposure occurred in April and August.
• People in 11 Local Government Areas were exposed to dengue virus.
• Routine dengue testing is recommended for febrile illnesses in Nigeria.

Outbreaks and sporadic dengue virus infections continue to occur in Africa. Several reports of dengue among travellers returning from some African countries to Europe and North America have raised concerns about the epidemiological situation in Africa. We investigated recent dengue infections in febrile patients during the rainy season in various urban centres in the rainforest region of Nigeria, West Africa. This cross-sectional study was conducted for 8 months in 2014 with study participants from Adeoyo Hospital Yemetu – Ibadan, Nigeria. Plasma were collected from 274 febrile patients residing in 11 Local Government Areas of Oyo State. IgM antibodies were determined using semi-quantitative sandwich ELISA. Data was analyzed using Chi - Square and Fisher's exact test with SPSS 16.0. An overall prevalence of 23.4% dengue virus infection was found among study participants. Highest monthly prevalence of 40% was in April and August. The monthly distribution pattern of dengue virus infection indicates efficient virus transmission. Routine diagnosis will enhance dengue virus surveillance and improve patient care in West Africa.

Detection of DENV IgM in a cross-section of febrile patients using ELISA to determine sero-prevalence in the rain forest region in West Africa.Figure optionsDownload as PowerPoint slide