Karnataka health minister Dinesh Gundu Rao has clarified that human metapneumovirus (HMPV) is not a new virus, emphasizing its long-standing existence

A common respiratory virus, HMPV is known to spike every winter and spring, health officials said. The virus has circulated among humans for at least six decades, experts added. Common symptoms include fever, cough, and nasal congestion. In severe cases, symptoms may result in bronchitis and pneumonia.

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.