Evaluation of the Performance of a Dengue NS1 Assay During the 2024 Epidemic in Brazil

Accurate diagnosis of dengue in the acute phase is crucial for proper patient management, reducing mortality rates, and enabling public health authorities to implement effective vector control measures. Our study, conducted during the 2024 dengue epidemic in Brazil, compared the results of a rapid dengue NS1 antigen detection assay with dengue RT-PCR using 300 serum specimens. Ninety-five percent of the patients reported symptoms consistent with dengue infection. We observed substantial agreement between the two tests (kappa = 0.8). The rapid NS1 test demonstrated 87% sensitivity and 92.7% specificity, using dengue RT-PCR as the gold standard. Our findings confirm that the rapid NS1 antigen detection test can be reliably used during the acute phase of dengue infection to provide an accurate diagnosis.