Cough, congestion or fever: Could you have the UK’s new ‘Mystery Virus’ HMPV?

Health authorities in the UK are closely monitoring a sharp rise in cases of human metapneumovirus (HMPV), a respiratory virus that recently caused a surge of illnesses in northern China. Initially dubbed a “mystery virus,” HMPV has sparked concern as it spreads to new regions, with UK cases increasing significantly over the past week.

The latest data from the UK Health Security Agency shows a huge surge in cases of HMPV in the UK, with a positivity rate of 4.9 per cent. The virus, which is part of the same family as RSV (respiratory syncytial virus), typically causes cold-like symptoms such as coughing, congestion and fever. However, it can lead to more severe respiratory problems in vulnerable groups, including young children, the elderly, and those with weakened immune systems.

Health authorities are now urging the public to take basic precautions to limit the spread of the virus. Measures include regular handwashing, wearing masks in crowded spaces and avoiding close contact with people who show symptoms of illness. Experts believe these steps, which became routine during the COVID-19 pandemic, can help slow the transmission of HMPV.

While HMPV has been known to scientists for decades, it has gained attention recently due to its sudden rise in cases and potential to strain healthcare systems. One of the main challenges is its similarity to other respiratory viruses, which can make it difficult to diagnose without specific testing. This means many cases may go unreported, and the actual number of infections could be higher than currently recorded.

What are the symptoms?

HMPV primarily affects the respiratory system and can cause a range of symptoms, from mild to severe. Most people experience:

• Cough
• Nasal congestion or a runny nose
• Sore throat
• Fever

For many, these symptoms are similar to those of a common cold or flu and resolve on their own within a few days. However, in vulnerable groups, the virus can lead to more serious respiratory problems. Young children, older adults, and individuals with weakened immune systems are at higher risk of complications, such as bronchiolitis or pneumonia. In severe cases, symptoms may include:

• Difficulty breathing
• Wheezing
• Extreme fatigue

Because these symptoms overlap with illnesses like RSV, the flu, or even COVID-19, it can be difficult to identify HMPV without specific testing.

In China, emergency measures were put in place to control the spread of HMPV, especially in the northern regions where hospitals were dealing with a high number of cases. Videos shared on social media showed hospital wards crowded with young children suffering from symptoms similar to COVID-19. This led to fears that the virus could become the ‘new’ Covid, but experts have assured the public that these scenes were not on the same scale as the beginning of the pandemic.

The World Health Organisation (WHO) has also clarified that the situation in China did not amount to a state of emergency, despite the rapid spread.

Although HMPV does not currently pose the same level of threat as COVID-19 once did, its spread does highlight the importance of early detection and response to emerging health threats. The virus could still place significant pressure on healthcare services if cases continue to rise, especially during winter when hospitals are already stretched by seasonal illnesses like the flu. The UK government is working with public health bodies to monitor the situation and ensure hospitals are prepared to handle any potential surge in cases.

For now though, health officials stress that there is no need for panic.