Human metapneumovirus: an underestimated cause of severe respiratory infection

Since its identification in 2001, human metapneumovirus (hMPV) has been recognized as an important cause of acute respiratory tract infection in all age groups. Although infection is often mild in healthy adults, hMPV can cause severe lower respiratory tract disease, including pneumonia, in young children, older adults, individuals with chronic diseases and immunocompromising conditions, and residents of long-term care facilities. Accumulating evidence demonstrates that hMPV contributes substantially to hospitalization, intensive care unit admission, and mortality in these high-risk populations. Globally, hMPV circulates seasonally, most commonly in late winter and spring, contributing to both community- and healthcare-associated respiratory infections; however, the COVID-19 pandemic disrupted established epidemiology, resulting in shifts in epidemic timing, off-season resurgences, genotype replacement, and increased overlap with other respiratory viruses, while also providing insights into viral interference and multivirus cocirculation. Clinical manifestations of hMPV overlap with other respiratory viruses, including influenza virus and SARS-CoV-2, and selective diagnostic practices contribute to under-recognition and undertesting. Although no specific antiviral therapies or licensed vaccines are currently available, identification of hMPV has important implications for diagnostic accuracy, prognosis, antimicrobial stewardship, and infection prevention, particularly in hospital and long-term care settings. This review summarizes current evidence on the virology, epidemiology, post–COVID-19 trends, clinical manifestations, outcomes, diagnosis, and prevention of hMPV, with a particular focus on adults and other high-risk populations. We also review the current landscape of hMPV vaccine development and its potential implications for clinical practice and public health.

Target Audience

Pulmonologists, critical care specialists, translational researchers, and clinicians

Learning Objectives

  • Identify patients at increased risk for severe human metapneumovirus infection who may benefit from enhanced diagnostic evaluation, monitoring, and supportive care.
  • Apply evidence-based diagnostic strategies to detect human metapneumovirus infection in adults with suspected lower respiratory tract infection.
  • Integrate current evidence on human metapneumovirus into infection control practices, including prevention and antimicrobial stewardship.

Course summary

Available credit: 
  • 1.00 AMA PRA Category 1 Credit(s)™

    The American Thoracic Society designates this Journal-based CME activity for a maximum of 1.00 AMA PRA Category 1 Credit(s)™. Physicians should claim only the credit commensurate with the extent of their participation in the activity.

  • 1.00 Participation
Publication Date: 
09/30/2026
Credit Expires: 
09/30/2028
Cost:
$25.00
Rating: 
0

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Accreditation Statement

The American Thoracic Society is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians.

Disclosure Declaration

Article Authorship Disclosures (as submitted to the ATS prior to article publication date)

Catia Cilloniz MSc, PhD, FERS (Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain), reported no relevant financial relationships with ineligible companies.

Antonia Ho (MRC-University of Glasgow Centre for Virus Research, Glasgow, UK) reported a grant from MRC (grant ref: MC_UU_00034/6) in support of this manuscript and Grant funding from UKRI, Wellcome Trust, MRC, Public Health Scotland and Medical Research Foundation.

Chanu Rhee (Department of Population Medicine, Harvard Medical School and Harvard Pilgrim Health Care Institute, Boston, MA, USA), reported grants from Centers for Disease Control and Prevention and the Agency for Healthcare Research and Quality. Additionally, Dr. Rhee reported royalties from UpToDate and consulting fees from DynaMed.

All other authors reported no relevant financial relationships with ineligible companies.

AnnalsATS CME Planners 

Margaret M. Hayes, M.D., (Harvard Medical School, Boston, MA, USA) reported receiving payments as an author for a chapter on heliox for UpToDate.

Caroline Okorie, M.D., M.P.H., (Stanford University School of Medicine, Stanford, CA, USA) reported no financial relationships with ineligible companies.

Off-Label Usage Disclosure

This activity includes discussion of investigational vaccines and vaccine candidates for human metapneumovirus (hMPV) that have not been approved by the U.S. Food and Drug Administration (FDA). No licensed antiviral therapies or vaccines for hMPV are currently available.

All relevant financial relationships have been reviewed and mitigated.

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Available Credit

  • 1.00 AMA PRA Category 1 Credit(s)™

    The American Thoracic Society designates this Journal-based CME activity for a maximum of 1.00 AMA PRA Category 1 Credit(s)™. Physicians should claim only the credit commensurate with the extent of their participation in the activity.

  • 1.00 Participation

Price

Cost:
$25.00
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