New Virus Outbreak In China After COVID-19: What is HMPV? Know Symptoms And Preventive Measures

Five years after COVID-19 outbreak, China has a new health headache: the sudden outbreak of HMPV in the country. According to sources, the viral infection is growing at an exponential rate, thereby overloading health facilities and crematories, all of which could be seen online through social media posts and videos that have surfaced on the viral network. Amid these concerns, other respiratory illnesses like influenza A, Mycoplasma pneumoniae, and COVID-19 are said to be also circulating simultaneously with the same conditions, making a heavy strain on the health services. As of this, neither the Chinese government nor the WHO has given official warnings or declared any emergency in these cases.

To combat this upsurge, Chinese health authorities have implemented a pilot system to track cases of pneumonia with unknown origins. This new initiative was launched by China's disease control agency to increase preparedness for respiratory outbreaks during the winter months, a drastic change from the way the nation responded to the COVID-19 pandemic.

This outbreak has affected mostly vulnerable populations, including children whose immune systems are still developing and elderly persons who have a pre-existing respiratory disease. The symptoms of HMPV tend to be those of a cold or flu-like illness, characterized by fever, coughing, and nasal congestion. In some cases, these infections can develop into bronchitis or pneumonia, which significantly increase the risk of complications for individuals with diseases like asthma or COPD.

What is Human Metapneumovirus (HMPV)?

First identified in the Netherlands in 2001, human metapneumovirus is a respiratory RNA virus within the Paramyxoviridae family. It is a seasonal virus, most actively circulating during the winter and spring seasons. This virus is responsible for one of the most significant causes of hospitalization in the acute respiratory infection (ARI) category among young children, after RSV.

Research indicates that almost all children older than five years have been infected with HMPV, although the immunity developed against subsequent infections is partial. Though it is more of a cold-season disease, cases have been reported throughout the year, with the prevalence of the disease fluctuating every year.

HMPV is commonly spread through contaminated respiratory droplets from infected person to person often by cough, sneeze, or the transfer of aerosolized microorganisms from touch of contaminated fingers on doorknobs and toys. Similar to RSV and influenza within the United States, HMPV follows an annual peak or surge that mostly occurs during winters and springs in many parts.

Human metapneumovirus Symptoms

HMPV infections are highly similar to some of the classic symptoms of 'common cold', they include:

Most symptoms of bronchiolitis go away in a few days. However, more severe cases may lead to complications such as bronchitis or pneumonia, or even life-threatening conditions. Sometimes, young children may suffer from severe bronchiolitis that can be fatal.

While HMPV can affect all age groups, it significantly affects the following:

Those with immature immune systems are highly susceptible to developing severe complications like bronchiolitis or pneumonia.

Individuals with conditions such as COPD, asthma, or pulmonary fibrosis have a higher chance of developing serious symptoms.

People who are undergoing chemotherapy or have recently received an organ transplant are highly vulnerable.

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Diagnosis of HMPV is usually based on a physical examination, patient history, and laboratory tests. In severe cases, advanced diagnostic techniques, like bronchoscopy, are applied to confirm the virus. Treatment is usually symptomatic as there are no specific antiviral therapies or vaccines for HMPV. Some treatments according to the American Lung Association include:

- Over-the-counter medications for relieving fever and pain.

- Inhalers or corticosteroids to control wheezing or harsh coughing.

- Prednisone is the prescription medication only in extreme conditions.

Human Metapneumovirus (HMPV) vs. COVID-19 HMPV and COVID-19 have similarities in their transmission modes and respiratory symptoms. HMPV is a seasonal virus, mostly surfacing during winter and spring. COVID-19, on the other hand, is a year-round virus, with emerging variants.

Surprisingly, the number of cases for other respiratory viruses, such as HMPV, rose drastically during this time as restrictions against COVID-19 relaxed. Scientific evidence shows that during the lockdowns, fewer instances of contact with regular viruses resulted in a vulnerability to them, including HMPV, after restrictions eased.

The only prevention from the virus, however is to avoid contracting it in the first place, particularly for high-risk populations. Dr. Sunil Kumar K, Lead Consultant - Interventional Pulmonology explains, "Preventive strategies include maintaining good hand hygiene, wearing masks in crowded places, and practicing respiratory etiquette, such as covering coughs and sneezes. It's also advisable to avoid close contact with individuals exhibiting respiratory symptoms. Given the absence of a vaccine, these measures are crucial in controlling the spread of the virus."

"While HMPV shares transmission characteristics with COVID-19, such as spread through respiratory droplets, it is generally less severe. However, co-circulation with other respiratory pathogens, including influenza and Mycoplasma pneumonia, as reported in China, can complicate clinical outcomes and pose additional challenges to public health systems.

Continuous surveillance and public awareness are vital in managing this outbreak. Learning from the COVID-19 pandemic, early detection, transparent communication, and adherence to preventive measures are key to mitigating the impact of HMPV and safeguarding public health."

Individuals with chronic conditions of the respiratory system should keep their environment, very clean and shy away from contaminated areas.

As respiratory illnesses continue to rise in China, health experts stress the importance of proactive measures and public awareness. While HMPV is typically mild, its potential to cause severe complications in vulnerable groups underscores the need for vigilance. For now, a combination of symptom management, robust healthcare systems, and effective monitoring initiatives will be critical in managing this growing health challenge.

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Human Metapneumovirus (hMPV). American Lung Association.