The epidemiology of medically attended respiratory syncytial virus in older adults in the United States: A systematic review
OBJECTIVE: This review was undertaken to assess the historical evidence of the disease incidence and burden of laboratory-confirmed respiratory syncytial virus (RSV) in medically attended older adults.
DESIGN: A qualitative systematic literature review was performed; no statistical synthesis of the data was planned, in anticipation of expected heterogeneity across studies in this population.
METHODS: A literature search of PubMed, Embase, and the Cochrane Library was conducted for studies of medically attended RSV in older adults (≥ 50 years) published in the last 15 years. Two independent reviewers screened titles and abstracts based on predefined inclusion and exclusion criteria.
RESULTS: From 10 studies reporting incidence proportions, RSV may be the causative agent in up to 12% of medically attended acute respiratory illness in older adults unselected for comorbidities, with variations in clinical setting and by year. In multiple studies, medically attended-RSV incidence among older adults not selected for having underlying health conditions increased with increasing age. Of prospectively followed lung transplant recipients, 16% tested positive for RSV. In hospitalized adults with chronic cardiopulmonary diseases, 8% to 13% were infected with RSV during winter seasons (8%-13%) or metapneumovirus season (8%). Hospitalizations for RSV in older adults typically lasted 3 to 6 days, with substantial proportions requiring intensive care unit admission and mechanical ventilation. Among older adults hospitalized with RSV, the mortality rate was 6% to 8%.
CONCLUSIONS: Protection of older adults against RSV could reduce respiratory-related burden, especially as age increases and the prevalence of comorbidities (especially cardiopulmonary comorbidities) grows.