Here’s what to know about human metapneumovirus (HMPV), a respiratory virus currently being detected in parts of the US.
Although the name may be unfamiliar to many, HMPV isn’t new. It was first identified in 2001 and typically follows a seasonal pattern, often appearing in January, peaking through March and April, and declining by June.
That usual timing was thrown off in recent years, with Covid-19 altering the normal circulation of several respiratory viruses. Even so, HMPV activity has been noted again this year in states including New Jersey and California.
According to the Centers for Disease Control and Prevention (CDC), HMPV ‘can cause upper and lower respiratory illness in people of all ages, especially in young children, older adults, and people with weakened immune systems’.
Common symptoms include coughing, fever, nasal congestion, and shortness of breath — signs that can resemble other respiratory infections, including Covid.
Experts believe the virus spreads in several ways: through droplets in the air when an infected person coughs or sneezes, via close personal contact such as touching, and by contact with contaminated surfaces followed by touching the eyes or mouth.
While clinicians can test for HMPV, there is currently no vaccine or specific antiviral treatment. Guidance generally focuses on isolating while sick and getting adequate rest to support recovery.
New Jersey has seen a notable rise in cases, with the New Jersey Department of Health reporting a significant increase in patients seeking emergency care linked to HMPV.
In California, the WastewaterScan Dashboard — which tracks infectious diseases through sewage monitoring — has reported high levels of HMPV in Northern California wastewater, as per USA Today.
HMPV has also been detected in LA County, though reported concentrations there have been described as low to moderate.
For many people, illness may be mild. However, those at higher risk can develop more serious complications, including pneumonia, or experience worsening symptoms if they have asthma or chronic obstructive pulmonary disease (COPD).
Professor Paul Griffin, director of infectious diseases at Mater Health Services in Brisbane, Australia, told the Guardian: “It certainly can and does cause severe disease, that’s why I think it’s important that people know it’s out there.
“The challenge is at the moment there’s not much we can do except educate people [that] it’s around to reduce transmission. There’s no vaccine or antivirals, although there are some vaccines in development.”
With no vaccine or targeted treatment currently available, health specialists continue to stress the importance of hygiene measures to help limit spread.