Human Metapneumovirus (HMPV)

Overview

Human metapneumovirus (HMPV) is a respiratory virus identified for the first time in 2001 by Dutch researchers. It belongs to the pneumoviridae family, which is further characterized by the presence of the respiratory syncytial virus (RSV). Human metapneumovirus (HMPV) is considered one of the major causes of respiratory diseases that start as mild colds and develop into severe conditions, such as pneumonia, in people with weaker immunity.

What Is Human Metapneumovirus (HMPV)?

HMPV usually causes upper respiratory infections but can sometimes cause lower respiratory infections including: Pneumonia Asthma exacerbations COPD flare-ups Most people get infected with HMPV before the age of 5. Though reinfections are common, subsequent infections are usually milder. Those at higher risk for severe outcomes include:

• Infants and young children
• Elderly individuals
• Immunocompromised people

HMPV mainly transmits during the winter and the early spring and is spread when people are closely in contact with infected people or surfaces.

Prevalence of HMPV

HMPV is highly prevalent. Research indicates that most children are infected at least once before the age of 5. In children, HMPV makes up about 10% of all respiratory infections. Besides these, reoccurring infections persist throughout life and vary in severity.

Symptoms of Human Metapneumovirus (HMPV)

Most HMPV infections are mild with symptoms of common cold:

• Cough
• Nasal congestion
• Running nose
• Fever
• Sore throat
• Nausea
• Vomiting
• Diarrhea

In rare cases, symptoms may lead to:

• Severe breathing difficulties
• Middle ear infections
• Persistent fever

If symptoms last more than two weeks or worsen, consult a doctor immediately.

How Prevalent Is HMPV?

Surprisingly, human metapneumovirus (HMPV) is relatively common. Most individuals are infected by the age of 5, according to research. Although you can contract it more than once in your lifetime, subsequent infections are usually less severe. In children, HMPV causes approximately 1 in 10 respiratory infections, but it doesn't discriminate—anyone can catch it. Certain groups, including young children, older adults, and those with weakened immune systems, are at greater risk of complications.

Is Human Metapneumovirus Contagious?

Yes, just like most viruses, HMPV is contagious. You get it from close contact with an infected person, perhaps during a handshake, shared food, or even just from the air when they sneeze. In the United States, human metapneumovirus has a seasonal pattern, usually appearing during the winter and early spring months, just like the flu. Understanding this may also help you take preventive measures against the bug.

How Severe Is Human Metapneumovirus?

For most individuals, HMPV results in mild, cold-like symptoms. Some people may develop more severe complications, such as:

- Wheezing
- Asthma exacerbations
- Dyspnea or shortness of breath
- Fatigue
- Bronchitis
- Severe bronchiolitis, a potentially fatal chest infection, especially in young children
- Pneumonia

It’s worth noting that while severe cases are rare, they can require hospitalization, especially in vulnerable populations.

How Does HMPV Compare to COVID-19?

At first glance, HMPV and COVID-19 share similarities. Both are contagious respiratory viruses with symptoms like a runny nose, cough, fever, and shortness of breath. They also spread in similar ways—through respiratory droplets and contact with contaminated surfaces. However, there are key differences:

Treatment: Unlike COVID-19, HMPV has no antiviral therapy or vaccine.
Seasonality: HMPV peaks during winter and spring, but COVID-19 can circulate year-round with the emergence of new variants.

In some countries, HMPV cases increased sharply when COVID-19 restrictions were eased, even tripling. This is believed by experts because measures taken for pandemics decrease exposure to other respiratory viruses; then, people become more vulnerable to infections once restrictions are relaxed.

Is Human Metapneumovirus the Same as RSV?

HMPV and RSV (respiratory syncytial virus) are not the same, though they are very similar. They both belong to the Pneumovirus family and can produce similar respiratory symptoms. Severe cases of HMPV tend to occur in children aged 6 to 12 months, whereas RSV is more likely to cause severe illness in infants younger than 6 months.

Causes and Transmission

HMPV is caused by a virus in the pneumoviridae family. It spreads through:

- Respiratory droplets from coughing or sneezing
- Direct contact like handshakes, hugs, or kisses
- Touching contaminated surfaces, such as door handles, phones, or toys

Diagnosis of Human Metapneumovirus

Healthcare providers diagnose HMPV using a combination of physical examinations, symptom review, and laboratory tests. Diagnostic methods include:

- Swab tests: Specimens from the nostrils or the throat that can be sent to the lab to be analyzed by rapid antigen or PCR tests for the virus
- Bronchoscopy: Rarely, a camera-tipped tube collects lung fluid samples in severe cases
- Chest X-rays: imaging to detect lung changes

In most cases, routine testing of HMPV is not practiced unless symptoms worsen or complications arise

Treatment and Care

Currently, there is no known cure or antiviral therapy specifically for HMPV. Symptomatic care is done as follows:

Home remedies

These include:

• Acetaminophen or ibuprofen for fever and pain
• Decongestants in case of nasal congestion
• Corticosteroid nasal sprays when there is pressure in the nasal passages
• In relieving wheezing and respiratory distress
• Hydration and rest is one's key to recovery

Antibiotics have no effect on HMPV, but will be prescribed in case of secondary bacterial infection.

Prevention of HMPV

Prevention mainly depends on limiting exposure and hygiene. The best methods include:

- Washing hands often with soap and water for a minimum of 20 seconds
- Avoid close contact with anyone who has an illness
- Sanitize frequently touched surfaces
- Cover the mouth and nose upon coughing and sneezing
- Continue to get updated vaccinations and also regular health checks