Detection of Dengue virus infection among febrile patients presumptively diagnosed with malaria in Ogun State, Nigeria

Background: In Nigeria, where malaria is endemic, greater than 70% of febrile illnesses are treated presumptively as malaria, often without a laboratory evaluation for other possible causes of fever. Dengue virus infection presents a significant health challenge in tropical regions, often exhibiting clinical symptoms similar to malaria. In Ogun State, Nigeria, febrile patients are frequently presumed to have malaria, potentially overlooking concurrent or alternative infections like dengue. Accurate diagnosis is crucial for appropriate treatment and management. The aim of this study was to determine the prevalence of dengue virus antibodies and antigen among febrile patients attending a state hospital in Ogun State. Methodology: Blood samples from 120 consenting febrile patients suspected of malaria in Ogun state were evaluated for the presence of malaria parasites by microscopic examination of Giemsa-stained blood smears and also tested for the presence of anti-dengue immunoglobulin M (IgM) and immunoglobulin G (IgG), as well as anti-non-structural protein (NS1) using lateral flow chromatographic immunoassay in line with manufacturer’s instructions. The study lasted for three months (January- March, 2024). Data analysis was done using the Statistical Package for the Social Sciences (SPSS). A p value <0.05 was considered statistically significant. Results: The percentage occurrence of Dengue IgG Ab only, NS1 Ag, IgM Ab + NS1 Ag and IgM Ab + IgG Ab + NS1 Ag combined were: 4.2%, 0.8%, 3.3% and 6.7%, respectively. In all, 50% tested positive to malaria. A statistically significant association (p=0.026) was found between gender and preventive practice. Females exhibited higher proportions of good preventive practice 45.0% compared to males (20.8%). A significant association (p=0.014) was observed between age range and Dengue NS1 antigen status. Conclusion: These findings imply dengue fever should feature as a prominent differential diagnosis for febrile illnesses and screening for dengue virus should be part of routine tests amongst patients that presents with febrile illness. Given the prevalence of dengue virus infections, there is also a need for a dengue control programme and public education to prevent outbreaks and occurrence of severe dengue complications.