A respiratory virus that doesn’t have a vaccine or a specific treatment regimen is spreading in some parts of California — but there’s no need to sound the alarm just yet, public health officials say.
A majority of Northern California communities have seen high concentrations of human metapneumovirus, or HMPV, detected in their wastewater, according to data from the WastewaterScan Dashboard, a public database that monitors sewage to track the presence of infectious diseases.https://www.latimes.com/california/story/2026-03-04/human-metapneumovirus-in-california-what-you-need-to-know?utm_source=firefox-newtab-en-us
A Los Angeles Times data analysis found the communities of Merced in the San Joaquin Valley, and Novato and Sunnyvale in the San Francisco Bay Area have seen increases in HMPV levels in their wastewater between mid-December and the end of February.
HMPV has also been detected in L.A. County, though at levels considered low to moderate at this point, data show.
While HMPV may not necessarily ring a bell, it isn’t a new virus. Its typical pattern of seasonal spread was upended by the COVID-19 pandemic, and its resurgence could signal a return to a more typical pre-coronavirus respiratory disease landscape.