The horrors of the coronavirus pandemic are still fresh in most minds. China, meanwhile, is threatened by the outbreak of another virus -- the Human metapneumovirus or HMPV. It belongs to the same group of viruses that cause RSV, measles and mumps, medical websites point out. HMPV causes symptoms similar to the common cold in humans. Children, sexaganerians (and above) and people with weak immune systems are most vulnerable to metapneumovirus. Studies show most HMPV cases are mild in nature and most people get it before they turn 5.