Cases of human metapneumovirus (HMPV) and other seasonal viruses are on the rise across the northern hemisphere in early 2025, according to the World Health Organization. While news reports and social media videos have caused concern about a potential HMPV outbreak in China,

Experts say the disease is likely not going to be the next pandemic and the worry is a result of heightened wariness for respiratory illness in a post-Covid world. HMPV is a respiratory virus that regularly circulates during cold and flu season.

As cases of the HMPV virus continue to increase in the U.S. and in China, here's what you need to know about the virus.