Another similarity to COVID: A case of HMPV can last about a week, with symptoms peaking around the third day, Dr. Hoy told us. However, you can still be contagious for several days after you're feeling better and your symptoms subside. This is especially the case for patients with compromised or weakened immune systems.

While cases are climbing in China, the situation is very different from what it was when Covid-19 emerged five years ago, medical experts say. HMPV has circulated in humans for decades.

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.

The human metapneumovirus is reportedly surging in China, but should Americans be concerned? Here's what to know about HMPV symptoms and more.

The WHO said Chinese data up to Dec 29 showed detections of HMPV, seasonal influenza, rhinovirus, and respiratory syncytial virus (RSV) have all increased in recent weeks, particularly in northern parts of China. Influenza is currently the most commonly reported cause of disease, it said.

Symptoms of HMPV are similar to that of the common cold and can include a cough, fever, runny nose, sore throat, wheezing, shortness of breath and a rash. It can also cause upper and lower respiratory infections.

While news reports and social media videos have caused concern about a potential HMPV outbreak in China, experts from the WHO, U.S. Centers for Disease Control and Prevention and other agencies say the rise is not currently a cause for concern and within the normal range for the season.