Respiratory syncytial virus (RSV) often causes respiratory tract infections manifesting symptoms of upper respiratory tract infection such as cold. This virus can also cause infections of lower respiratory tract such as bronchiolitis, inflammation of small airways in the lung, and pneumonia. RSV is the most frequent cause of bronchiolitis in infants. Almost all children have been infected with RSV by the age of two. In infants and small children symptoms appear four to six days after exposure to the virus, and the majority of children recover within seven to fourteen days.
At first infection with RSV, in around 25-40 children out of 100, the illness manifests as bronchiolitis or pneumonia symptoms, and 5-20 children out of 1000 infected ones will need to be admitted to hospital. Most frequent hospital admissions are among children younger than six months.
As RSV infection does not ensure permanent protection against future infections, adults can also become infected with RSV, but these repeated infections have a milder clinical course. However, in those at risk, such as children born prematurely, those younger than 2 years with congenital heart or lung disease, and children with weakened (compromised) immune system, RSV infections may be severe and life-threatening.
Man is the only reservoir of infection. The virus spreads through close contact – large droplets emitted via coughing, sneezing or kissing – with infected person and indirectly by touching contaminated surfaces (e.g. toys, surfaces) or hands. In moderate climates RSV epidemics occur in winter and early spring, from November until March each year, in regular epidemic cycles every 8-14 months.
How to protect yourself
In spite of numerous investigations, vaccine against RSV is not available yet. However, spread of RSV may be prevented by simple steps, especially when symptoms of common cold are present:
- wash hands regularly (yours and the child’s)
- avoid places where many people gather, especially closed ones
- avoid sharing a child’s personal belongings (pacifiers, glasses, cutlery)
- wash toys more frequently
If your child belongs to a group at a high risk of developing severe form of disease caused by RSV, consult your physician about additional steps you might take.