West Nile Virus Exposure in Gezira State, Sudan: An ELISA-Based Study

West Nile Virus (WNV) is a mosquito-borne flavivirus responsible for West Nile fever. Although most infections are asymptomatic or mild, fewer than 1% progress to West Nile neuroinvasive disease (WNND), which has an estimated fatality rate of 10% (Petersen et al., 2013). This cross-sectional study assessed WNV exposure among 400 residents of Gezira State, Sudan (2019–2022). Blood samples were collected and analyzed for WNV-specific IgG and IgM antibodies using ELISA, while RT-PCR was performed on IgG-positive samples to detect active viral RNA. Overall, 62.3% (249/400) of participants were positive for WNV-IgG antibodies, indicating past exposure, whereas all samples were negative for WNV-IgM antibodies, suggesting the absence of recent infection. No significant correlations were observed between common risk factors and IgG positivity (P > 0.05), except for neck stiffness, which showed a significant association (P < 0.05). The high prevalence of WNV-IgG antibodies, coupled with the absence of IgM positivity, highlights widespread prior exposure and a lack of current infection in the population. These findings underscore the need for sustained surveillance and public health initiatives focusing on mosquito control and community awareness to prevent future WNV outbreaks.