Abstract

Background: Dengue fever (DF) is a mosquito-borne viral infection with rising global incidence, posing a significant public health challenge in many tropical regions, including Sudan. Kassala State has witnessed recurring outbreaks, underscoring the need for updated epidemiological data. Objective: To assess the prevalence of recent dengue virus infection among febrile patients and explore demographic and clinical associations with seropositivity. Methodology: A cross-sectional study was conducted from January to April 2025 in Kassala State. Febrile patients were enrolled, and 3 mL blood samples were collected 4–6 days after fever onset. Serum samples were tested for anti-DENV IgM using a commercial ELISA. Data were analyzed using SPSS version 28. Results: Among 93 patients tested, 83 (89.2%) were positive for DENV IgM and 10 (10.8%) were negative. The highest positive cases occurred in the 1–5 year age group (43.3% of seropositive cases). 47/93 (50.5%) were male and 46/93 (49.5%) were female. The majority (90.3%) reported symptom duration of 3–7 days. Urban residents comprised 74.2% of the patients, with no significant association between residence (urban vs. rural) and seropositivity (P = 0.23). Reported symptoms among IgM-positive patients included fever (100%), headache (89.2%), vomiting (52.7%), bleeding (16.1%), and convulsions (10.8%). There were no statistically significant associations between DENV IgM seropositivity and age group (P = 0.075), gender (P = 0.97), or duration of symptoms (P = 0.65). Conclusion: A high rate of recent dengue infection was observed among febrile patients in Kassala State, indicating active transmission and the need for strengthened surveillance and control measures.

Keywords

dengue virus, IgM antibodies, ELISA, kassala, Sudan, febrile illness, arboviruses