Measurements of disease burden necessitate a clear case definition, but current surveillance for RSV in humans uses multiple case definitions with “debatable” accuracy, according to results published in the Journal of Public Health.

Francesco Vitale, MD, of the University of Palermo and colleagues noted that RSV is responsible for many cases of influenza-like illnesses (ILI) among elderly adults, as well as severe acute respiratory infections (SARI). They conducted a study to assess the accuracy of different case definitions used in RSV surveillance. The following search query was used on PubMed and Scopus to perform a systemic literature review, with a 15-year-old baseline age restriction: ‘Respiratory Syncytial Virus’ OR ‘RSV’ OR ‘hRSV’ AND ‘case definition.’

Assessing Current Definitions

Among the 12 records assessed by the researchers, more than half (58%) used the SARI definition, 50% used the ILI definition, and 42% used the acute respiratory infection (ARI) definition, with some overlap.

For adults aged 18-64, most studies reported an RSV prevalence that ranged from 6.25 to 72.54 cases per 1,000 per year; prevalence ranged from 19.23 to 98.5 in older adults. Dr. Vitale and colleagues found that the outpatient ARI and hospitalized SARI criteria were especially sensitive and specific. “Disease burden measurement requires a clear case definition; however, current literature is questionable,” Dr. Vitale and col – leagues wrote. “Currently, RSV surveillance uses numerous case definitions with debatable accuracy. The epidemiology, clinical characteristics, and disease burden of RSV are difficult to characterize without a standard surveillance case definition.”