China’s mystery virus surge sparks global concerns over HMPV

Western health experts are calling on China to increase transparency about a viral outbreak that is overwhelming its hospitals, as evidence shows the virus is also gaining ground in the United States.

Beijing has dismissed viral footage showing overcrowded hospital waiting rooms, labeling respiratory infections as “less severe” and “smaller in scale” compared to last year. However, some fear parallels to the 2019 Covid outbreak, which was initially downplayed by China, may exist.

HMPV: The Suspected Culprit Behind China’s Outbreak

The outbreak in China is believed to be driven by human metapneumovirus (HMPV), a relatively lesser-known virus that typically causes mild cold-like symptoms, such as congestion, headaches, chills, and fatigue.

Dr. Sanjaya Senanayake, an infectious disease expert from The Australian National University, emphasized the importance of China sharing timely data about the outbreak. “It’s vital to understand who is being infected,” he said, adding that genomic data is necessary to confirm HMPV as the cause and ensure no significant mutations are present. Such information would be key to guiding potential vaccine development.

HMPV Cases Rising in the US

In the United States, HMPV cases are also on the rise. The Centers for Disease Control and Prevention (CDC) reported that the percentage of positive tests doubled throughout December, with nearly 300 cases confirmed in the last week of the month. Despite this, the CDC stated it is monitoring the situation and currently sees no cause for concern in the U.S.

Seasonal Virus or Something More?

Dr. Andrew Catchpole, chief scientific officer at hVIVO, highlighted that HMPV is a common seasonal virus in colder months. However, he noted that infection rates in China appear unusually high. “Normally, it’s not a major concern for hospitalizations, but it’s unclear whether the spike is due to the virus itself or coinciding high flu and Covid levels,” he said.

HMPV was first discovered in 2001 and is generally associated with mild symptoms. Severe cases, however, can lead to bronchitis, bronchiolitis, and pneumonia, with children, the elderly, and immunocompromised individuals most at risk.

China’s Response Under Scrutiny

China’s CDC has advised citizens to take precautions, such as frequent hand washing, while downplaying concerns about overwhelmed hospitals. Chinese foreign ministry spokesperson Mao Ning stated that respiratory infections are typical in winter and less severe than the previous year.

Nevertheless, experts like Vasso Apostolopoulos from RMIT University stress the importance of enhanced monitoring and timely responses, particularly in densely populated regions.

Experts Offer Reassurance

Many experts caution against drawing comparisons to the Covid-19 pandemic. Unlike Covid, HMPV is a known virus with established testing methods. Professor Jill Carr from Flinders University explained that HMPV is unlikely to cause a global crisis. “The scientific community already understands its genetic diversity and epidemiology, unlike the uncertainty surrounding Covid’s emergence,” she noted.

Similarly, Professor Andrew Easton of the University of Warwick said HMPV has posed a consistent but manageable risk for at-risk populations since its discovery over 20 years ago.

Hypervigilance or Real Concern?

The CDC’s recent data suggests HMPV test positivity rates in the U.S. remain slightly higher than last year. However, experts like Dr. Paul Hunter from the University of East Anglia caution that increased diagnoses may partly reflect better molecular testing rather than a genuine rise in cases.

Dr. Jacqueline Stephens from Flinders University attributed heightened concern to post-Covid vigilance. “Hearing terms like human metapneumovirus can sound alarming, but we’re simply more aware of outbreaks now,” she said.

While the CDC continues to monitor developments in China, it reassured that the situation currently poses no significant threat to the U.S.