Human Metapneumovirus (hMPV) Meet the Human Metapneumovirus, commonly known as hMPV! This little virus was first identified in 2001, and has since been recognized as a prevalent cause of respiratory infections in both children and adults worldwide. Be it bronchitis or pneumonia, hMPV has been associated with a range of severe respiratory disorders. The virus makes a strenuous appearance mostly during the winter and spring seasons, making sure you pay attention to the seasonal cough and cold.