Burden of Respiratory Syncytial Virus Infection in Immunocompromised Adults: A Systematic Review of the Evidence From High-Income Countries

Individuals with immunocompromising conditions or receiving immunosuppressive therapy are at increased risk for severe outcomes and complications from respiratory syncytial virus (RSV). An in-depth systematic investigation into severe RSV disease among immunocompromised adults is lacking. We therefore performed this systematic literature review to summarize the literature (2000-2024) on the burden of RSV disease across a broad spectrum of immunocompromising conditions in adults residing in high-income countries, in terms of the incidence of RSV infection and the prevalence of hospitalizations, complications, and mortality among RSV-infected individuals. Relevant English-language articles were retrieved through PubMed and Embase searches. We included 36 articles in our review. All but four studies were conducted in Europe or the USA. Most evaluated solid organ transplant recipients (n = 11, including 8 evaluating lung transplants) or hematopoietic stem cell transplant recipients (n = 17). Our review shows that, in most studies, substantial proportions of RSV-infected immunocompromised adults required hospitalization (37.5-87.5% in lung transplant, 37.7-68.0% in any solid organ transplant, and 30.3-83.9% in stem cell transplant recipients), intensive care unit admission (11.7% in lung, 3.9-17.9% in any solid organ, and 4.8-29.8% in stem cell transplant recipients), and mechanical ventilation (0.0-10.4% in lung, 3.9-14.3% in any solid organ, and 2.7-29.8% in stem cell transplant recipients). Data from the identified articles indicate that in solid organ (especially lung) and stem cell transplant patients, the degree of immunosuppression-determined by anti-rejection regimens, corticosteroid dosing, and other adjunctive agents-may be an important determinant of the risk of RSV. Our review confirms that RSV poses a significant burden on immunocompromised adults, emphasizing the need to implement preventive strategies such as vaccination in this population.