RSV Incidence Likely Underestimated Due to Low Rates of Testing

More than three-quarters of US hospitals tested fewer than 1 in 4 older adults hospitalized with lower respiratory tract infection (LRTI) for respiratory syncytial virus (RSV), according to a study published in Infectious Diseases and Therapy.

“These findings imply that relying on retrospective real-world database analyses to determine the RSV-related hospitalization incidence can result in a substantial underestimation of the true RSV incidence,” researchers wrote. “Current incidence estimates based on real-world administrative data should be adjusted upwards to account for this underestimation.”

Researchers used the all-payer Premier Healthcare Database (PHD) to identify 937 US hospitals with LRTI-related hospitalizations of adults aged 65 and older during the 2016-2019 RSV seasons. Proportions of patients with RSV testing were calculated.

Most hospitals infrequently tested for RSV during LRTI hospitalization of older adults, according to the study. The median percentage of LRTI hospitalizations with RSV testing was just 4.3%. Some 78.4% of hospitals tested for RSV in less than 25% of patients hospitalized with LRTI.

Testing varied considerably by hospital type, the study found. Testing was significantly higher in hospitals with 200 or more beds compared with less than 200 beds (median 9.1% vs 1.6%), in teaching hospitals compared with non-teaching hospitals (11% vs 2.5%), and in urban compared with rural (7.4% vs 0.7%) hospitals.

Over time, RSV testing across all inpatient visits increased from a median 0.8% in the 2016-2017 season to 6.3% in the 2018-2019 season.

“A strength of our analysis is the size and comprehensiveness of the PHD database, which lends high generalizability to our study findings,” researchers wrote. “Further, the results from these analyses were straightforward and transparent, with a clear indication of low RSV testing frequency, which can lead to an underestimated RSV incidence.”

Reference

Rozenbaum MH, Judy J, Tran D, Yacisin K, Kurosky SK, Begier E. Low levels of RSV testing among adults hospitalized for lower respiratory tract infection in the United States. Infect Dis Ther. 2023;12(2):677-685. doi:10.1007/s40121-023-00758-5