human case metapneumovirus (HMPV) is a relatively unknown respiratory infection that is on the rise across the United States, prompting health authorities to increase surveillance. Data shared by the U.S. Centers for Disease Control and Prevention shows that about 5% of positive respiratory cases nationwide in early March were caused by the virus, and wastewater surveillance has also shown increased activity of the virus.
The surge in cases observed since autumn 2025 is a cause for concern because the disease is often associated with common coldwhich is even harder to tell without testing.
Officials said that while most cases remain mild, the lack of a vaccine or specific antiviral treatments has increased concerns, especially among vulnerable populations.
Also read: HMPV cases in India: What is it and how is it spread? Experts share symptoms
What is HMPV?
HMPV is a respiratory virus first discovered in 2001 and belongs to the same family as respiratory syncytial virus. It typically cycles in a seasonal pattern, peaking from winter to spring in the United States.
The virus is spread through respiratory droplets released when an infected person coughs or sneezes, and through close contact such as shaking hands or touching contaminated surfaces and faces, according to the Centers for Disease Control and Prevention.
Symptoms are similar to common infections
One of the challenges with HMPV is that its symptoms are very similar to other respiratory illnesses. Patients usually present with cough, fever, nasal congestion and shortness of breath. In some cases, the infection can escalate into a more serious condition, such as bronchitis or pneumonia.
Dr Tyler B Evans, an infectious disease doctor, told MailOnline that “HMPV is not a serious problem for the vast majority of people outside of these groups.” However, he added that in high-risk groups, “it can develop into lower respiratory tract disease,” particularly in shared living environments.
Also read: HMPV vs Covid-19: Know the key differences and dangers
Who is at higher risk?
Health experts warn that infants and young children, people over 65 and people with weakened immune systems are more likely to develop severe illness. Outbreaks in settings such as nursing homes or shelters are particularly concerning because they spread more quickly.
no vaccine yet
There is currently no vaccine or targeted therapy for HMPV. The CDC notes that care is largely supportive and most people recover on their own.
To reduce the risk of infection, authorities recommend basic preventive measures such as frequent hand washing, avoiding close contact with sick people, disinfecting frequently touched surfaces, and maintaining good indoor ventilation.
 cases in the US has health authorities on alert. ){kind=link}