Paramyxovirus (Paramyxoviridae)

 Paramyxovirus is a genus of negative-sense RNA viruses, including subfamily of human metapneumovirus respiratory syncytial virus (RSV), pneumonia virus of mice (PVM), and avian pneumoviruses. RSV is a leading cause of pneumonia and bronchiolitis in infants and the elderly and is estimated to cause 3 million lower respiratory tract infections and more than 60,000 deaths worldwide each year. Two major RSV subtypes, A and B, circulate with 1-2 epidemic periods per year. The RSV fusion (F) glycoprotein is a dominant antigen and a prominent vaccine target, and has been determined in the pre- and postfusion states.