Seasonal respiratory viruses and specialist lung assessment
The Rise in Viral Respiratory Infections: Human Metapneumovirus
Human metapneumovirus can cause symptoms ranging from a mild cold to bronchiolitis, pneumonia or worsening of an existing lung condition. Although it has recently received greater public attention, hMPV is not a new virus. Understanding who is at risk, when testing is useful and when respiratory assessment is needed can help patients obtain appropriate care.
- What hMPV is
- Symptoms
- Testing
- High-risk patients
- Treatment
- Prevention
- Post-viral symptoms
Human metapneumovirus is not new
The virus was identified in 2001, but research indicates that it had circulated in humans for decades before its discovery. Wider molecular testing has made it easier to identify.
Most infections are managed supportively
There is currently no specific approved antiviral treatment or licensed vaccine for hMPV. Severe illness may require oxygen, fluids or hospital care.
What is human metapneumovirus?
Human metapneumovirus, commonly abbreviated to hMPV or HMPV, is a respiratory virus that can infect the nose, throat, airways and lungs. It belongs to the Pneumoviridae family, which also includes respiratory syncytial virus.
hMPV can affect people of all ages. In many healthy adults and children it causes a self-limiting upper-respiratory illness similar to a common cold.
In susceptible people, however, infection can spread into the lower respiratory tract and cause bronchitis, bronchiolitis or pneumonia. It can also aggravate asthma, COPD, bronchiectasis or another existing respiratory condition.
People can be infected more than once during their lifetime. Previous infection does not always produce complete, lifelong protection.
hMPV is an established seasonal respiratory virus—not a newly emerged pandemic virus. Increased awareness may reflect seasonal circulation, more respiratory testing and greater public attention to viral infections.
Why are viral respiratory infections receiving more attention?
Several respiratory pathogens can circulate during the same season, including influenza, RSV, SARS-CoV-2, rhinovirus and hMPV. This can produce substantial pressure on healthcare services, particularly during colder months.
Seasonal circulation
In temperate climates, hMPV is commonly detected from winter into spring, although infection can occur at other times.
Several viruses circulate together
Similar symptoms may be caused by hMPV, influenza, RSV, COVID-19 or another respiratory virus.
More molecular testing
Multiplex PCR panels can test for several respiratory viruses at once, increasing recognition of infections that were previously labelled simply as viral illness.
Greater public awareness
The COVID-19 pandemic increased awareness of respiratory surveillance, transmission and the impact of infection on vulnerable people.
Changing seasonal patterns
Respiratory-virus circulation was disrupted during the pandemic, and the timing of some seasonal epidemics subsequently changed.
An ageing and vulnerable population
Older age, chronic disease, cancer therapy, transplantation and immunosuppression increase the number of people at risk of complications.
A rise in reported infections does not necessarily mean the virus has become more dangerous
Case numbers can be influenced by season, testing availability, healthcare attendance and surveillance. Severity should be judged using hospitalisation, intensive-care and mortality data rather than case counts alone.
How does hMPV spread?
hMPV spreads in ways similar to other respiratory viruses. Infection can pass between people through respiratory particles, close contact and contaminated hands or surfaces.
Respiratory particles
Coughing, sneezing, talking and breathing can release infectious particles into the surrounding air.
Close personal contact
Transmission is more likely during prolonged close contact, especially in enclosed or poorly ventilated spaces.
Hands and surfaces
Infection may occur after touching a contaminated object and then touching the eyes, nose or mouth.
Household and care settings
Families, nurseries, care homes, hospitals and other shared environments can facilitate respiratory-virus transmission.
Symptoms of human metapneumovirus
Symptoms overlap considerably with other viral respiratory infections. It is usually not possible to identify hMPV from symptoms alone.
Mild infection may feel like a cold. More significant lower-airway infection can cause persistent fever, wheeze, chest discomfort, rapid breathing, reduced oxygen levels or difficulty breathing.
Symptoms may reflect more than one process
Wheeze may result from viral airway inflammation or an asthma exacerbation. Breathlessness may reflect pneumonia, COPD, bronchiectasis, heart disease, deconditioning or another condition. Clinical assessment is important when symptoms are significant or prolonged.
Who is at greater risk of severe hMPV infection?
Babies and young children
Young children may develop bronchiolitis, croup, wheezing or pneumonia. Feeding difficulty and dehydration can accompany respiratory symptoms.
Older adults
Older adults may have reduced physiological reserve and a higher risk of pneumonia, oxygen requirement, frailty-related decline or hospital admission.
People with weakened immunity
Risk may be greater in people receiving chemotherapy, transplant treatment, prolonged corticosteroids or other immunosuppressive medicines.
Significant immune deficiency can also lead to prolonged viral shedding or more extensive lower-respiratory disease.
People with chronic lung or heart disease
Asthma, COPD, bronchiectasis, pulmonary fibrosis and significant cardiovascular disease may increase the impact of respiratory infection.
Viral infection may aggravate baseline cough, mucus, breathlessness, wheeze or oxygen requirements.
hMPV in people with asthma, COPD or bronchiectasis
Asthma
Viral infection can trigger wheeze, chest tightness and reduced peak flow. Patients should follow their prescribed asthma action plan and seek review if reliever use increases.
COPD
hMPV can contribute to a COPD exacerbation, causing increased breathlessness, cough, wheeze or sputum. Oxygen levels and the need for additional treatment may require assessment.
Bronchiectasis
Viral infection can increase airway inflammation and mucus production. A secondary bacterial exacerbation should be considered when sputum becomes more purulent or symptoms worsen.
Pulmonary fibrosis
Patients with limited respiratory reserve may become more breathless during infection and should seek early assessment if oxygen levels fall or recovery is delayed.
Continue prescribed respiratory treatment unless advised otherwise
Do not stop inhaled corticosteroids, bronchodilators or other regular respiratory medicines simply because the illness is viral. Patients should follow their individual treatment or exacerbation plan and obtain medical advice when control worsens.
How is hMPV diagnosed?
Many mild viral illnesses do not require identification of the exact virus. Testing becomes more useful when the result may influence infection control, clinical monitoring or the investigation of severe disease.
- Clinical assessment The clinician reviews symptoms, duration, oxygen levels, medical history and risk factors for severe disease.
- Respiratory examination Examination may identify wheeze, crackles, increased breathing effort or signs of dehydration or systemic illness.
- Respiratory PCR testing A nose or throat sample may be tested using a molecular panel that detects hMPV and other respiratory viruses.
- Oxygen measurement Pulse oximetry helps identify reduced oxygen saturation, although readings must be interpreted with the clinical picture.
- Chest imaging when needed Chest X-ray or CT may be appropriate when pneumonia, another complication or an alternative diagnosis is suspected.
- Additional investigations Blood tests, sputum culture or other tests may be required in people with severe symptoms, immune suppression or chronic lung disease.
A positive viral test does not exclude another problem
A patient can have hMPV together with bacterial pneumonia, an asthma exacerbation, pulmonary embolism, heart failure or another illness. Persistent or disproportionate symptoms require clinical reassessment.
How is human metapneumovirus treated?
There is currently no routinely approved antiviral medicine specifically for hMPV. Treatment is mainly supportive and depends on illness severity and the patient’s underlying health.
| Treatment | Possible role | Important points |
|---|---|---|
| Rest and fluids | Support recovery and reduce dehydration during mild illness | Fluid intake may need individual adjustment in heart or kidney disease |
| Paracetamol or appropriate pain relief | Reduce fever, headache, throat discomfort and muscle aches | Follow dosing guidance and check for contraindications |
| Bronchodilators | May help wheeze in asthma, COPD or reactive airway disease | Should be used according to the prescribed respiratory plan |
| Oxygen | Used in hospital when oxygen levels are clinically low | Oxygen targets may differ in patients at risk of carbon dioxide retention |
| Intravenous fluids or nutritional support | May be required when oral intake is inadequate | More likely in infants, frail adults or severe illness |
| Antibiotics | Used only when bacterial infection is suspected or confirmed | Antibiotics do not treat hMPV itself |
Antibiotics do not treat viral infection
Antibiotics may be needed when bacterial pneumonia or a bacterial exacerbation is suspected, but they should not be used automatically for an uncomplicated hMPV infection.
How to reduce transmission
Stay home when unwell
Avoid close contact with vulnerable people while feverish or acutely unwell with respiratory symptoms.
Improve ventilation
Opening windows or improving airflow can reduce the concentration of respiratory particles indoors.
Cover coughs and sneezes
Use a tissue or the inside of the elbow, dispose of tissues and clean hands afterwards.
Clean hands regularly
Wash with soap and water or use an appropriate alcohol-based hand sanitiser when handwashing is unavailable.
Consider a mask
A well-fitting mask can provide additional protection in crowded, poorly ventilated spaces or around vulnerable people.
Keep other vaccinations current
There is no licensed hMPV vaccine, but recommended influenza, COVID-19, pneumococcal and RSV prevention can reduce the burden of other respiratory infections.
When a private respiratory assessment may help
A specialist assessment may be useful when symptoms are persistent, recurrent, disproportionate or difficult to distinguish from an existing lung condition.
Prolonged cough
Persistent cough may require assessment for post-viral airway sensitivity, asthma, infection or another respiratory cause.
Ongoing breathlessness
Spirometry, lung volumes, gas transfer or imaging may help identify an underlying respiratory abnormality.
Worsening asthma or COPD
Review can assess inhaler treatment, lung function, oxygen levels and whether infection or another complication is present.
Recurrent viral or chest infections
Investigation may consider bronchiectasis, immune deficiency, airway disease, aspiration or an environmental exposure.
Abnormal chest imaging
Persistent infiltrates, nodules, airway changes or other findings may need specialist interpretation and follow-up.
Post-infection fitness decline
Exercise assessment may help distinguish respiratory limitation, cardiovascular factors and deconditioning when recovery is slower than expected.
When to seek urgent medical help
Seek urgent assessment for significant deterioration
- Severe or rapidly worsening breathlessness
- Blue or grey lips, collapse or confusion
- A marked fall in oxygen saturation
- Chest pain with breathlessness or fainting
- Inability to keep fluids down or signs of dehydration
- Persistent high fever with worsening general condition
- Severe wheeze not responding to the prescribed treatment
- New respiratory symptoms during chemotherapy, transplantation or intensive immunosuppression
Call 999 for severe breathing difficulty, collapse, blue lips or another immediately life-threatening symptom.
Conclusion
Human metapneumovirus is a well-established seasonal respiratory virus rather than a newly emerged infection. Wider testing and greater awareness have made it more visible.
Most infections cause cold-like symptoms and improve with rest, fluids and appropriate symptom relief. However, hMPV can cause bronchiolitis, bronchitis or pneumonia and may aggravate asthma, COPD, bronchiectasis or another chronic lung condition.
Babies, older adults, immunocompromised people and patients with underlying lung or heart disease have a greater risk of severe illness.
PCR testing may identify hMPV, but testing is not necessary for every mild illness. It is more useful when disease is severe, the patient is vulnerable or the result will influence clinical or infection-control decisions.
There is currently no specific approved antiviral treatment or licensed hMPV vaccine. Management is supportive, while antibiotics are reserved for suspected or confirmed bacterial infection.
Persistent cough, breathlessness, recurrent infection or reduced exercise capacity after a viral illness should be assessed in context rather than assumed to be normal post-viral recovery.
Frequently asked questions
Is human metapneumovirus a new virus?
No. It was identified in 2001, but evidence indicates that it had circulated in people for decades before its discovery.
Is hMPV the same as RSV?
No. They are different viruses within the same broader virus family and can cause similar upper- and lower-respiratory symptoms.
How can I tell whether I have hMPV, flu or COVID-19?
Symptoms overlap substantially, so the precise virus cannot usually be identified reliably without appropriate testing.
Is there a vaccine for hMPV?
There is currently no licensed hMPV vaccine. Vaccine research is continuing.
Is there an antiviral medicine for hMPV?
There is currently no routinely approved antiviral treatment specifically for hMPV. Care is mainly supportive.
Do antibiotics treat hMPV?
No. Antibiotics treat bacterial infections, not viruses. They may be prescribed when a bacterial complication is suspected or confirmed.
Can hMPV cause pneumonia?
Yes. Pneumonia is less common than mild upper-respiratory illness but is more likely in older adults, young children, immunocompromised people and those with underlying disease.
Can hMPV worsen asthma or COPD?
Yes. Viral infection can trigger wheeze, increased breathlessness and loss of disease control. Patients should follow their prescribed action plan and seek assessment when symptoms are significant.
How long does hMPV infection last?
Many mild infections improve within several days, although cough and fatigue may last longer. Severe infection and underlying lung disease can prolong recovery.
When should persistent symptoms be investigated?
Seek assessment when symptoms are worsening, unusually prolonged, associated with low oxygen levels, or accompanied by recurrent infection, significant breathlessness, chest pain or weight loss.
References and further information
- World Health Organization. Human metapneumovirus infection: questions and answers. View WHO information
- Centers for Disease Control and Prevention. About human metapneumovirus. View CDC information
- Jobe NB, et al. Human metapneumovirus seasonality and co-circulation with respiratory syncytial virus—United States, 2014–2024. Morbidity and Mortality Weekly Report. 2025;74. View the CDC surveillance report
- World Health Organization. Advisory on trends of acute respiratory infection, including human metapneumovirus. 2025. View the WHO advisory
