Potential conflicts of interest. T. V. H. reports grants from the NIH paid to her institution. Personal fees for NIH/NHLBI council member, co-chair of the American Thoracic Society Vaccine and Immunization initiative; Parker B. Francis council of scientific advisors grant reviewer, UpToDate content writer, speaker honorarium from the AAAAI, member data safety and monitoring board for Pfizer. Both authors have submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Conflicts that the editors consider relevant to the content of the manuscript have been disclosed.