Respiratory syncytial virus (RSV) infection may cause serious illness and lead to death in older adults (≥ 65 years), causing over 60,000 hospitalizations and 6,000 deaths each year in the United States. Seroprevalence rates vary by age and geographic location but are typically high due to the repeated nature of RSV infections. This study investigated the seroprevalence of antibodies against human RSV in a convenience sample of adults from Olmsted County, Minnesota. Of the 480 subjects studied, 83.8% tested RSV IgG positive, 8.1% tested RSV IgG negative, and 8.1% had equivocal results. Additional cohorts from recently vaccinated individuals or those with a recent diagnosis of RSV infection were tested for comparison, yielding antibody positivity rates of 95.8% and 97.5% respectively.

The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Dr. Poland is the chair of a Safety Evaluation Committee for novel investigational vaccine trials being conducted by Merck Research Laboratories. Dr. Poland provides consultative advice to AiZtech; GlaxoSmithKline; Merck & Co. Inc.; Moderna; and Syneos Health. Dr. Poland is an adviser to the White House and World Health Organization on COVID-19 vaccines and monkeypox, respectively. Drs. Poland and Ovsyannikova hold patents related to vaccinia and measles peptide vaccines. Drs. Kennedy, Poland, and Ovsyannikova hold a patent related to vaccinia peptide vaccines. Drs. Poland, Kennedy, and Ovsyannikova have received grant funding and royalties from ICW Ventures for pre-clinical studies on a peptide-based COVID-19 vaccine. Drs. Poland, Kennedy, Ovsyannikova and Haralambieva hold a patent related to the impact of single nucleotide polymorphisms on measles vaccine immunity. Dr. Kennedy has received funding from Merck Research Laboratories to study waning immunity to mumps vaccine. Dr. Kennedy also offers consultative advice on vaccine development to Merck & Co. and Sanofi Pasteur. These activities have been reviewed by the Mayo Clinic Conflict of Interest Review Board and are conducted in compliance with Mayo Clinic Conflict of Interest policies. This research has been reviewed by the Mayo Clinic Conflict of Interest Review Board and was conducted in compliance with Mayo Clinic Conflict of Interest policy.

This study was funded by Mayo Clinic internal funds

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The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

The Mayo Clinic Institutional Review Board gave ethical approval for this work (IRB#: 08-007049)

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I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance).

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All data produced in the present study are available upon reasonable request to the authors