BackgroundIn children, respiratory infections such as SARS-CoV-2, respiratory syncytial virus (RSV), and influenza share similar clinical signs and symptoms. Here we compared the performance of a rapid antigen diagnostic test using a self-collected anterior nasal swab (COVID-VIRO ALL IN TRIPLEX) and multiplex RT-PCR. MethodsFrom October to December 2022, in the emergency pediatrics unit of Orleans Hospital, France, we evaluated the diagnostic accuracy of the triplex test. ResultsFor the 263 children, sensitivity of the test was 88.9% (95%CI 51.8–99.7), 79.1% (95%CI 64.0–90.0), and 91.6% (95%CI 84.1–96.3), for SARS-CoV-2, RSV, and influenza, respectively. Specificity was 100% for each virus. For RT-PCR with cycle threshold < 32, sensitivity was 100.0% [95%CI 59.0–100.0], 87.2% [95%CI 72.6–95.7] and 92.3% [95%CI 84.896.9] for SARS-CoV-2, RSV, and influenza respectively. ConclusionsThis easy-to-perform triplex test is a considerable advance, allowing clinicians to obtain an accurate diagnosis in most cases of respiratory infection. More data are needed to validate this test in different contexts and across several seasons.