Rising HMPV cases in China spark concerns

CHENNAI: Planet Earth stood still in the year 2020 when COVID hit, triggering a worldwide shutdown of all human interactions. History may not repeat itself this time, mercifully, as the medical fraternity is far more prepared to prevent a global spread of the Human Metapneumovirus (HMPV) that threatens to wreak havoc on the breathing populace.

However, media reports on the rise in the cases of HMPV in China and the related social media messages are bringing back flashbacks of 2020 as the COVID-19 infection had its genesis in China’s Wuhan province.

Visuals of overcrowded hospitals with alleged cases of HMPV have been a cause for concern in the neighbouring countries, especially India.

However, the situation is under control, stated health authorities in China and the Union Health Ministry, who also advised the public not to panic. While China has reported a rise in respiratory illnesses, triggered by HMPV, the Union Health Ministry pointed out that there was no surge in influenza cases or any other winter respiratory diseases.

What is HMPV?

The Human Metapneumovirus, another flu-like virus with influenza-like symptoms, was discovered in 2001 in nasopharyngeal aspirate samples of children with respiratory infections caused by unknown pathogens. Serological studies have shown that it has existed for at least 60 years, being identified all over the world as a common respiratory pathogen.

HMPV belongs to the Pneumoviridae Metapneumovirus genus, which is an enveloped single-stranded negative-sense RNA virus. The diagnosis can be made through a rapid antigen test or Polymerase Chain Reaction (PCR)

Transmission

Similar to common cold and flu, HMPV is mainly transmitted through droplets or aerosols produced by coughing and sneezing. It can spread through close contact with infected people and exposure to virus-contaminated environments.

As per the Chinese Centre for Disease Control and Prevention (CCDCP), the incubation period after infection is around 3-5 days. Getting infected with HMPV puts the patients at risk for repeated infection.

HMPV can be detected throughout the year, but the detection rate is highest during winter and spring. Additionally, HMPV infection can also cause outbreaks. However, unlike COVID-19, HMPV is considered a winter illness and a surge in cases is more common in cold temperatures.

At-risk individuals

HMPV infections are reportedly more common in children under 14 years. Immunocompromised populations and the elderly are also vulnerable and can be co-infected with other respiratory viruses.

Symptoms include cold, cough, fever, nasal congestion, wheezing and shortness of breath, with potential complications like bronchitis and pneumonia.

A Lancet report from September 2023 titled ‘Neutralising Antibodies Against Human Metapneumovirus’ states that HMPV has a global prevalence and seasonal distribution similar to most respiratory viruses. Children younger than 5 years are the primary target population, with infants younger than 12 months at high risk of severe infection.

It is estimated that HMPV can lead to over 14 million suffering from acute lower respiratory infections and fatalities in the 1:1000 ratio. Such deaths are attributed to HMPV annually among children younger than 5 years. Another report in Lancet Global Health from 2021 stated that 1% of acute lower respiratory infection-related fatality in children under 5 years can be attributed to HMPV.

Currently, there is no vaccine or effective medication against HMPV. Treatment is mostly focused on alleviating symptoms, similar to influenza.

Mask-up, wash hands

The CCDCP has advised the public to wear a mask when going to crowded places. Also, frequent hand-washing, having proper ventilation, and scientific disinfection can effectively reduce the chance of HMPV infection, it stated.

The Chinese Foreign Ministry recently stated that respiratory infections tend to peak during the winter season in the Northern Hemisphere. “Diseases appear to be less severe and spread on a smaller scale compared to the previous year. The Chinese government cares about the health of its citizens and foreigners in China. It’s safe to travel in China,” said Mao Ning, spokesperson, Chinese Foreign Ministry.

The Director of Public Health and Preventive Medicine Dr TS Selvavinayagam urged the public not to panic. “There are thousands of pathogens around us, each having a different mode of invasion, pathogenesis and implications. A surveillance system is in place at the global, national and state levels, which will alert us if there is a real challenge. There’s no need to panic with reports of every infection across the globe. The state is fully prepared to handle any public health emergency, if any.”