Hospitalization costs for adults infected with human metapneumovirus (hMPV) are comparable to those hospitalized with respiratory syncytial virus (RSV) infection, researchers reported today on Open Forum Infectious Diseases.

The retrospective study, based on patient data from Kaiser Permanente Southern California, examined total hospitalization costs for adults who tested positive for hMPV or RSV and were hospitalized from July 2011 through July 2024. A total of 5,775 adults who tested positive for hMPV (2,810) and RSV (2,965) were included in the study. 

“Although the economic impact of influenza-, SARS-CoV-2-, and RSV-associated disease in adults has been studied extensively, there are limited data on hMPV-associated healthcare costs in adult populations,” researchers from Kaiser Permanente and drugmaker AstraZeneca, which funded the study, wrote. 

AstraZeneca makes the monoclonal antibody Nirsevimab, which protects infants against RSV, and is developing a vaccine for hMPV.

Adults hospitalized with hMPV had slightly shorter hospital stays than those with RSV (6.4 vs 6.8 days), similar proportions of intensive care unit admission (14.8% vs 16.5%) and respiratory support requirement (24.8% vs 25.7%), and a greater proportion of pneumonia diagnosis (66.7% vs 56.8%). The adjusted mean hospitalization costs were $20,188 for hMPV and $21,759 for RSV. 

The study authors say the burden of disease associated with RSV and hMPV infection in older adults is considerable. 

“The increasing proportion of older adults combined with the high cost of hospitalization for hMPV and RSV underscore the importance of the development of vaccines and therapeutics directed against both hMPV and RSV,” the authors wrote.