TOPLINE:

Respiratory syncytial virus (RSV) infections occurred more frequently than human metapneumovirus (hMPV) infections in adults with chronic underlying health conditions. The odds of RSV test positivity were more than 60% higher than those of hMPV across settings.

METHODOLOGY:

• Researchers conducted a systematic review and meta-analysis of observational and interventional studies to compare the disease burden of hMPV- and RSV-positive respiratory tract infections among adults with chronic underlying health conditions.
• They searched six databases — MEDLINE, EMBASE, Global Health, CINAHL, Web of Science, and Global Index Medicus — for studies from 2001 onward; a total of 50 studies were included.
• Key eligibility criteria included laboratory-confirmed hMPV and RSV infections, adults aged 18 years or older, and sample sizes of at least 100 tested episodes or specimens for test-positivity outcomes.
• Most studies (88%) were conducted in high-income countries; only six were conducted in lower-middle-income and upper-middle-income countries.

TAKEAWAY:

• In inpatient settings across 22 studies, the odds of testing positive for RSV were 88% higher than the odds of testing positive for hMPV among adults with at least one chronic illness (odds ratio [OR], 1.88; P < .001).
• A meta-analysis of 32 studies found that across all settings, adults with at least one chronic illness had higher 65% higher odds of testing positive for RSV than for hMPV (OR, 1.65; P < .001).
• Significant differences between RSV and hMPV test positivity were seen among adults with chronic respiratory disease (annual OR, 2.02; seasonal OR, 1.42), cardiovascular disease (seasonal OR, 1.53), immunocompromised status (annual OR, 1.47), or hematologic diseases (annual OR, 2.11; P < .05 for all). No significant difference was seen among solid organ transplant recipients.

IN PRACTICE:

“Human metapneumovirus and RSV contribute substantially to the respiratory disease burden among adults with chronic underlying health conditions, with RSV generally being more frequent,” the authors wrote.

SOURCE:

The study was led by Durga Kulkarni, University of Edinburgh, Edinburgh, Scotland. It was published online on June 8, 2026, in Open Forum Infectious Diseases.

LIMITATIONS:

Studies reporting only hMPV or only RSV were excluded. Most included studies were descriptive and not designed to estimate effect sizes. Heterogeneity in populations and study designs further complicated evaluation, and selective reporting could not be ruled out.

DISCLOSURES:

This study was supported by AstraZeneca. Several authors disclosed institutional grants, institutional consulting fees, lecture payments to the institution, support for meetings, and participation on advisory boards from multiple organizations.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.