Respiratory syncytial virus, illustration - stock illustration

Respiratory syncytial virus (RSV) particles, computer illustration. This pneumovirus, a type of paramyxovirus, is a major cause of human respiratory tract infections in patients of all ages. Each virion consists of RNA (ribonucleic acid) genetic material enclosed in a protein coat, or capsid, within a phospholipid envelope. The envelope is covered in protein spikes, which enable the virus to attach to and enter a host cell. In adults, RSV only affects the upper respiratory tract, but in infants bronchiolitis (bronchiole inflammation) or bronchopneumonia can result.