People who are clinically immunosuppressed should not have this vaccine because the vaccine strain could replicate too much and cause a serious infection. This includes babies whose mothers have had immunosuppressive treatment while they were pregnant or breastfeeding. For more information see the MHRA's Drug Safety Update (April 2016).
The chickenpox vaccine is not recommended for pregnant women as a matter of caution. However, studies have not shown any link between the weakened virus in the vaccine and any specific problems in babies born to women who received a chickenpox vaccine while they were pregnant. These have not shown any link between the weakened virus in the vaccine and any specific problems in babies born to these women. See this Public Health England statement for more information.
Studies have shown that the vaccine virus does not get passed to the baby through breast milk, so it is safe for breast-feeding women to be vaccinated (see the Green Book chapter on Varicella, page 438).
Why the chickenpox vaccine is not offered routinely in the UK
The Joint Committee on Vaccination and Immunisation (JCVI), which advises the UK Government, has so far advised that it would not be cost effective to introduce the chickenpox vaccine or the MMRV vaccine into the routine UK schedule. As long as most children received the vaccine it would be very effective in reducing cases of severe chickenpox disease, but it is thought that cases of shingles in older people would increase.
Shingles is very expensive for the NHS to treat. It is believed that many adults in the UK get their immunity to chickenpox boosted by coming into contact with children who have the disease. Several studies have shown that this may make adults less likely to develop shingles as they get older.
If a chickenpox vaccine was introduced but not taken up by many people, there might be more adults who did not receive the vaccine or have “wild” chickenpox in childhood. They would then be at an increased risk of severe chickenpox infection as adults.
However, the JCVI is currently reviewing data from other countries where the vaccine has been in routine use over the past decade or two. It will use this to see what impact the chickenpox or MMRV vaccine is having on chickenpox and on shingles, and then advise the Government on whether there should be any change to the current advice on chickenpox vaccine. For more information see the JCVI minutes from October 2009.
Information about other treatments
A treatment called human varicella zoster immunoglobulin (VZIG) is given to people in risk groups who have been exposed to chickenpox. Immunoglobulins are special concentrated antibody preparations which provide immediate short-term protection against disease. VZIG can help to reduce the severity of chickenpox symptoms for some people in risk groups.
Chickenpox vaccine outside of the UK
The chickenpox vaccine currently available in the UK is a single vaccine. However, several countries use a vaccine that combines the measles, mumps and rubella (MMR) vaccine with a chickenpox (varicella) vaccine, called the MMRV vaccine.
For children aged two and younger, studies have shown that more of them develop fever after the MMRV vaccine, compared with giving the MMR vaccine and the chickenpox vaccine separately on the same day. In particular there is an increased risk of febrile convulsions (fits). These occur 7-10 days after MMRV vaccination.