Pneumovirus (Pneumoviridae)

Pneumovirus is a genus of negative-sense RNA viruses, including subfamilies of human Metapneumovirus (hMPV) or Orthopneumovirus, such as human respiratory syncytial virus (RSV). hMPV has been circulating in humans for at least a half century prior to its discovery in 2001. Almost all humans are infected with hMPV by the age of five with potential re-infections. hMPV circulates as two genotypes, A and B, which is further grouped into four subgroups, A1, A2, B1, and B2.

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.