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Is the vaccine safe?
The vaccine can be given to people with a previous history of shingles infection. It should not be given to anyone who currently has shingles. As stated above, the vaccine should not be given to people who are clinically immunosuppressed (either due to drug treatment or underlying illness) because the vaccine strain could replicate too much and cause a serious infection. For more information see the MHRA's Drug Safety Update (April 2016) .
In clinical trials of the vaccine, there have been no reports of someone who was vaccinated passing the virus on to anyone else. However, because the shingles vaccine is a live vaccine, it is thought that this may be possible in rare cases.
There is thought to be a very small risk that someone who has been vaccinated could pass on the virus to someone who is not immune to chickenpox. This is only thought to be a risk if the person who has been vaccinated develops a shingles type rash at the injection site or elsewhere on the body.
The shingles vaccine is not recommended for pregnant women as a matter of caution. However, studies have been carried out on pregnant women who have accidentally received chickenpox or shingles vaccines. 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.