Chinese health officials are observing a rise in human metapneumovirus (HMPV) cases, although they report that this increase appears to be within normal expectations and does not indicate the emergence of a new respiratory virus. The World Health Organization (WHO) has noted that the overall scale and intensity of respiratory infectious diseases in China this year remain lower than that of the previous year.
Recent data indicates that HMPV cases have also been climbing in the United States since late November, with the Centers for Disease Control and Prevention (CDC) reporting a 1.94% positivity rate for HMPV in tests as of late December 2024. In comparison, the flu’s positivity rate stood at 18.71%, and COVID-19 at 7.10%. Experts attribute the heightened activity of various respiratory viruses during the winter season to increased indoor gatherings, particularly around the holidays.
HMPV, discovered in 2001 and belonging to the Pneumoviridae family, causes respiratory illnesses that can affect individuals of all ages, with its symptoms being similar to those of other respiratory viruses, such as cough, nasal congestion, fever, and shortness of breath. Young children and older adults, especially those with underlying health conditions, are at a higher risk of severe complications like bronchitis or pneumonia.
The virus spreads through respiratory secretions, making direct contact and touching contaminated surfaces another route of transmission. Most people have likely been exposed to HMPV by the time they reach the age of five, and while re-infection is possible, symptoms are usually less severe upon subsequent exposures.
Currently, there are no antiviral treatments specifically for HMPV; management focuses on supportive care for those experiencing moderate to severe symptoms. This includes administering bronchodilators for wheezing and hydration for those who are dehydrated. Patients may also need antibiotics if secondary bacterial infections arise.
Preventive measures include practicing good hygiene, such as frequent handwashing and wearing masks in crowded settings—especially for high-risk groups—along with staying home when ill. Vaccination against other respiratory illnesses like COVID-19, influenza, and RSV is also recommended to reduce the risk of co-infections that could complicate recovery.
As researchers and health officials continue to monitor the situation, there is a positive outlook due to increased awareness and diagnostic capabilities surrounding respiratory viruses, which could lead to better management of any potential HMPV cases that arise in the coming months. Understanding and addressing respiratory health remains a priority, especially during the winter season when such viruses tend to thrive.