A Cross-Sectional Study in Northeast India to Assess Malaria, Scrub Typhus, and Dengue in Patients with Acute Febrile Illness Using ELISA

Abstract Aim Acute febrile illness (AFI) is a major reason for hospitalization in tropical and subtropical regions. Overlapping clinical features might also lead to confusion about the diagnosis of AFI. In India, dengue, scrub typhus, and malaria continue to be the most prevalent causes. Early laboratory validation using ELISA-based assays is essential for timely medication and a reduction in morbidity and death. Methods Using commercial ELISA kits to detect dengue NS1 antigen, dengue IgM antibodies, scrub typhus IgM antibodies, and malaria pLDH antigen in accordance with manufacturer instructions, a cross-sectional study of 200 patients presenting with AFI—95 urban and 105 rural residents—was carried out. Data on demographics, residential status, and length of fever were recorded, and statistical analysis was carried out using PAST software. Result The results showed that 51% of the patients were male and 49% were female. Patients from rural areas made up a higher proportion (53%) than those from metropolitan areas (47%). 16% of patients in cities were positive for dengue NS1, 7% for dengue IgM, 12% for scrub typhus, and 17% for malaria. Dengue (18%), scrub typhus (19%), and malaria (22%) were more prevalent among rural people. Longer fevers, particularly those lasting between 6 and 14 days, were related to greater positives. Malaria and scrub typhus were the leading causes of AFI. Conclusion ELISA-based diagnostics are useful for early detection of AFI etiology. Higher rural incidence highlights the importance of improved monitoring, early diagnostic access, and focused public health interventions.