Diagnostic accuracy of a molecular-based point-of-care test for rapid detection of respiratory syncytial virus in children admitted to high-dependency care in Nepal.

Background: Rapid respiratory syncytial virus (RSV) diagnostics are largely unavailable in low-resource settings. We compared the diagnostic accuracy of a molecular-based point-of-care test (POCT) with standard reverse transcription polymerase chain reaction (RT-PCR) in children admitted to high-dependency care. Methods: We analysed data from a larger study (RSV GOLD - ICU Network study) in two Nepali tertiary hospitals over two respiratory seasons. Children aged ≥4 days and <2 years admitted to high-dependency units were tested for RSV using POCT at admission. We calculated sensitivity, specificity, and predictive values of POCT against laboratory RT-PCR on stored samples as the gold standard. Results: We analysed 124 randomly selected stored samples, of whom 70 (56.5%) tested positive with POCT and 74 (59.7%) with RT-PCR. The median cycle threshold (CT) value was 29.1 (interquartile range = 25.1-33.4). All cases with false-negative POCT had low viral loads (CT value >31). The sensitivity (93.2%; 95% confidence interval (CI) = 86.0, 97.5), specificity (98.0%; 95% CI = 91.5, 99.9), positive predictive values (98.6%; 95% CI = 93.9, 99.9), and negative predictive values (90.7%; 95% CI = 81.1, 96.6) of POCT for RSV infection were all satisfactory. Conclusions: We conducted the first prospective study showing excellent accuracy of molecular RSV POCT in a poor resource setting. Affordable molecular-based POCT in resource-constrained settings can improve care of children with acute respiratory infections and strengthen surveillance for vaccine effectiveness during rollout of RSV interventions.