Recently, RSV-LRTI prevention trials for a long-acting, monoclonal antibody (mAb) and a maternal RSV F protein (RSV-F) vaccine were published 4,5, as was a systematic review and meta-analysis assessing the risk of recurrent wheeze given early childhood RSV-LRTI 2. While public health programs for prevention of RSV-LRTI would be major accomplishments, the impact of such programs on chronic respiratory illness is unknown, but would likely be small.Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.Acknowledgements There was no specific funding for this study. Product Product efficacy1 Medically-attended, respiratory syncytial virus lower respiratory tract infection (RSV-LRTI) attack rate2 Relative risk for recurrent wheeze in RSV-LRTI vs. non-RSV-LRTI children3 Baseline risk of recurrent childhood wheezing illness4 Relative risk of recurrent wheeze in intervention vs. control groups5 Trial sample size, both arms (1:1 randomization)5 Number needed to treat5 Maternal RSV F protein vaccine 44.4% 9.5% 2.45 4.9% 0.95 179,353 334 44.4% 9.5% 2.45 9.5% 0.95 87,526 172 44.4% 9.5% 2.45 20.0% 0.95 36,172 82 Long-acting, monoclonal antibody 70.1% 9.5% 2.45 4.9% 0.92 70,865 212 70.1% 9.5% 2.45 9.5% 0.92 34,615 110 70.1% 9.5% 2.45 20.0% 0.92 14,343 52 Table 1 Total sample sizes for efficacy trials of RSV-LRTI prevention to demonstrate a significant effect on recurrent childhood wheezing outcomes and number needed to treat.