Respiratory syncytial virus respiratory infection morbidity and mortality in adult populations

Purpose of review

Respiratory syncytial virus (RSV) is increasingly recognized as an important cause of morbidity and mortality in adults, particularly in older adults and those with frailty, immunosuppression, or chronic diseases. This review aims to assess the epidemiology, clinical burden, complications, and long-term outcomes of RSV infection in adults.

Recent findings

The burden of RSV in adults is underestimated, and age alone does not well identify those at risk of severe disease. Frailty is associated with a more than threefold higher risk of severe disease. Bacterial co-infection has been reported in up to 23% of hospitalized adults undergoing microbiological testing, with Streptococcus pneumoniae and Haemophilus influenzae as the most common pathogens. Acute cardiac events occur in about one in five hospitalized adults. Clinically relevant functional decline was reported in 28% of patients at 6–12 months.

Summary RSV causes acute and long-term morbidity in vulnerable adults. Risk assessment should consider frailty, comorbidities, and immune status in addition to age. Better identification of high-risk adults may help guide prevention and clinical management.