Metapneumovirus Nucleoprotein (MPV NP) [hMPV57]

Metapneumovirus is a discovered paramyxovirus of the subfamily Pneumovirinae, which also includes avian pneumovirus and human respiratory syncytial virus (HRSV). Human metapneumovirus (HMPV) is classified as a member of the family Pneumoviridae, which comprises large enveloped negative-sense RNA viruses. This taxon was formerly a subfamily within the Paramyxoviridae family but was reclassified in 2016 as a separate family with two genera, Metapneumovirus (which includes HMPV) and Orthopneumovirus (which includes respiratory syncytial virus). HMPV is an enveloped virus with a nonsegmented negative-sense RNA genome. HMPV is most closely related phylogenetically to avian metapneumovirus (APV). The complete genome sequence reveals a high level of homology with APV. Phylogenetic analysis has identified two subgroups of HMPV, subgroups A and B, and two clades within each of these subgroups (designated A1, A2, B1, and B2), which often circulate concurrently. A study of 727 Australian HMPV isolates was undertaken from 2001 to 2004 to determine the epidemiologic profile of genetic subtypes associated with acute respiratory tract infections. Concurrent annual circulation of all four HMPV subtypes was common, although a single, and usually different, HMPV subtype predominated each year. HMPV is an important cause of respiratory disease worldwide, can cause upper and lower respiratory disease in people of all ages, especially among young children, older adults, and people with weakened immune systems. Broader use of molecular diagnostic testing has increased identification and awareness of HMPV as an important cause of upper and lower respiratory infection.