Chickenpox (varicella)

Caused by highly contagious virus; causes low grade fever and vesicular rash.

Effects of the disease

One in 100,000 patients develops encephalitis (brain inflammation). About three in 100,000 patients die. Infection during pregnancy can result in congenital malformations in the baby. Onset of chickenpox (varicella) infection in the mother in the period five days before to two days after delivery results in severe infection in the newborn baby in up to one-third of cases.

How to immunise and when

The combination measles, mumps, rubella and varicella (MMRV) vaccine is given at 18 months of age. This vaccine replaced the second dose of measles, mumps, rubella (MMR) vaccine previously given at 4 years of age and the varicella vaccine at 18 months of age.

The vaccine should not be given to pregnant women, but it is safe to vaccinate children who are in contact with pregnant women.

Side effects of immunisation

One in 100 recipients may develop swelling of the salivary glands. One in three million recipients develops mild encephalitis (inflammation of the brain).

More serious reactions are rare. Thrombocytopenia (bleeding or bruising) is very rarely associated with the measles, mumps, rubella vaccine, occurring in three to five per 100 000 doses of vaccine administered.

If you have any concerns about side effects of vaccines, talk to your doctor or nurse.

Page last updated: 10 Aug 2017