Low Levels of RSV Testing Among Adults Hospitalized for Lower Respiratory Tract Infection in the United States.

A small proportion of older adults hospitalized with LRTI are tested for RSV in US hospitals. Large variability occurs across hospital types. Consequently, retrospective database analyses likely result in a substantial underestimation of the true RSV-related hospitalization incidence. RSV incidence studies using real-world data need to assess for RSV testing frequency and adjust their results for under ascertainment associated with limited testing.