Varicella is an infectious disease caused by a virus. Children in good general health usually recover from it in approximately one week. In an adult who has not had varicella before, the varicella virus can cause a serious infection and difficult complications. Varicella contracted during pregnancy, in particular, can cause a significant risk of complications to both the mother and the foetus. Varicella may also be dangerous to patients whose immune system is compromised.
A varicella vaccine is recommended to everyone over 13 years of age who has not had the disease. It is also recommended for health care professionals who have not had the disease and other persons working with children. In addition, a vaccination is recommended for those who care for or live in the same household with persons with immune deficiency. Vaccinating those who are in close contact with persons with immune deficiency reduces the risk of the latter contracting varicella. A varicella vaccination can also be given to all children from the age of 12 months.
The vaccination does not necessarily prevent the person from contracting the virus. For persons under 13 years of age whose general health is good, one vaccine is sufficient in preventing the serious forms of varicella. A series of two vaccinations can also be used. The goal of two doses is to prevent varicella infection completely. Two doses are recommended for people over 13 years of age.
If it is known that a person has had varicella, there is no need to vaccinate them. Sometimes it is unclear whether a person has actually had varicella. However, vaccinating a person who has had the disease does not do any harm.