Cases of human metapneumovirus (HMPV), a relatively lesser-known respiratory infection, are rising across the United States, prompting increased monitoring by health authorities. Data shared by the Centers for Disease Control and Prevention shows the virus accounted for around 5% of positive respiratory tests nationwide in early March, with wastewater surveillance also pointing to heightened activity.
The surge, observed since fall 2025, has drawn attention because the illness often mimics the common cold, making it harder to distinguish without testing.
Officials say that while most cases remain mild, the absence of a vaccine or specific antiviral treatment adds to concerns, especially for vulnerable populations.
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What is HMPV?
HMPV is a respiratory virus first identified in 2001 and belongs to the same family as Respiratory Syncytial Virus. It typically circulates in seasonal patterns, peaking from winter through spring in the US.
According to the CDC, the virus spreads through respiratory droplets released when an infected person coughs or sneezes, as well as through close contact such as handshakes or by touching contaminated surfaces and then the face.
Symptoms resemble common infections
{{/usCountry}}According to the CDC, the virus spreads through respiratory droplets released when an infected person coughs or sneezes, as well as through close contact such as handshakes or by touching contaminated surfaces and then the face.
Symptoms resemble common infections
{{/usCountry}}One of the challenges with HMPV is that its symptoms closely mirror other respiratory illnesses. Patients commonly experience cough, fever, nasal congestion and shortness of breath. In some cases, the infection can escalate into more serious conditions such as bronchitis or pneumonia.
Dr Tyler B Evans, an infectious diseases physician, told the Daily Mail that “for the vast majority of people outside those groups, HMPV is not a serious concern.” However, he added that in high-risk groups, “it can progress to lower respiratory tract disease,” particularly in shared living environments.
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Who faces higher risk?
Health experts warn that infants and young children, older adults above 65, and individuals with weakened immune systems are more likely to develop severe illness. Outbreaks in settings like nursing homes or shelters can be especially concerning due to faster transmission.
No vaccine yet
There is currently no vaccine or targeted treatment available for HMPV. The CDC notes that care is largely supportive, with most people recovering on their own.
To reduce the risk of infection, authorities recommend basic preventive measures such as frequent handwashing, avoiding close contact with sick individuals, disinfecting commonly touched surfaces, and maintaining good ventilation indoors.