Probable primary and secondary dengue viral infections and associated host factors among university undergraduates in Osun State, Nigeria

Introduction: According to the World Health Organization, global dengue cases have continually increased in recent decades. In resource-poor countries, such as Nigeria, diagnoses are often missed, putting the general population at risk of significant mortality and morbidity. This study investigated exposure to dengue virus (DENV) and probable primary and secondary DENV infections among new undergraduates in Southwestern Nigeria. Methodology: Institutional-based retrospective study was carried out among 89 eligible undergraduates selected using systematic sampling method. The students were tested for the presence of DENV IgM and IgG antibodies using ELISA kits. Data were statistically analyzed using the SPSS software version 23.0 vis-a-vis their serologic results. Results: Students aged 15-33 years (mean age: 19.7 +/- 2.9 years). Mean age of the 46 female students (19.8 +/- 3.2 years) was comparable (p = 0.64) to that of the 43 males (19.5 +/- 2.7 years). DENV IgM and IgG prevalence rates were 41.6% and 33.7%, respectively. Unlike DENV IgG prevalence, older age (18-33 years) and feminine gender were, respectively, associated with IgM positivity (p = 0.05 [odds ratio (OR) = 2.7]; p = 0.001 [OR = 4.7]). Probable primary and secondary DENV infections were 22.5% and 33.7%, respectively, with 43.8% of the students being susceptible to DENV infection. Those with primary infections not only stood the risk of secondary heterotypic infections with possibility of severe dengue but they might also be infectious to Aedes mosquitoes, thus further spreading the virus. Conclusions: The observed high antibody prevalence rates further establish local endemicity of dengue and calls for intensification of prevention efforts targeting the general population.