As China experiences a rise in respiratory infections this winter, one little-known virus has gotten a lot of attention – and some people may worry whether the rise in cases could be felt more broadly around the world.

As China continues to monitor an increase in cases of human metapneumovirus (HMPV), here's what you need to know about the illness.

Cases of human metapneumovirus, or HMPV, are in the U.S. too, and it looks similar to other seasonal illnesses. Here's what to know before you panic.