Nosocomial infection with respiratory syncytial virus (RSV) is an important health risk in pediatric care but is largely preventable by efficient infection control measures. Commonly applied rapid antigen detection tests (RADTs) miss a considerable number of RSV-infected patients. The objective of our analysis was to evaluate whether readily available host parameters are associated with false-negative RADT, and to assess how these parameters could be applied in an optimized RSV isolation strategy.We retrospectively analyzed a cohort of 242 children under the age of 2 years hospitalized with acute respiratory tract infection to identify host parameters associated with false-negative RADT test result. We subsequently simulated the outcome of different isolation strategies based on RADT result and host parameters in view of the overall isolation efficacy.Out of 242 hospitalized patients, 134 (55%) patients were found RSV-positive by RT-PCR, whereas 108 (45%) patients were tested negative. The performance of the RADT was compared with the result obtained by reverse transcription polymerase chain reaction on the identical nasopharyngeal wash. Overall, we found that 85 patients (35%) were tested true positive, 108 (45%) were tested true negative, whereas a false-negative test result was obtained in 49 patients (20%). Duration of respiratory symptoms for >3 days and a respiratory admission diagnosis are associated with false-negative RADT result. In comparison with RADT alone, consideration of these clinical parameters and RADT result can decrease the rate of nonisolated RSV-infected patients from approximately 24% to 8% (65% RSV pretest probability).Consideration of both RADT and clinical parameters associated with false-negative RADT can result in an optimized RSV infection control policy.