The WHOrecommends the use of rubella vaccine in all countries with well-functioning childhood immunization programmes where reduction or elimination of CRS is considered a public health priority.

According to the WHO, “the primary purpose of rubella vaccination is to prevent the occurrence of congenital rubella infection including CRS, which is an important cause of deafness, blindness and mental retardation.”

Rubella itself is a mild and generally harmless illness. The trouble arises when a woman in the early weeks of pregnancy catches the disease and puts her baby at risk of birth defects or even death. Rubella (CRS) is a condition affecting around 90% of babies of mothers who contracted rubella in early pregnancy. The rates of CRS are not, however, numerically very high and especially not in countries such as the United Kingdom.

What is the real risk of giving a pregnant woman rubella if you fail to vaccinate your child?

This is important because it is a moral reason frequently cited by those who argue in favour of vaccination. They say that it is incumbent on all of us to protect unborn children by vaccinating the population at large. However, it appears from the WHO information that a foetus will in fact be almost completely protected from rubella if its mother has immunity.

The WHO says:

Natural rubella infection normally confers lifelong immunity. There have been rare cases of serologically documented re-infections either after earlier natural infection or after vaccination. Re-infection in pregnancy resulting in CRS has occasionally been reported in women with natural or vaccine-induced immunity, but the risk to the fetus is low.”

So the only babies having a material risk of CRS are those whose mothers have chosen not to be vaccinated and have no natural immunity: and even then the risks are relatively low because of the low incidence of rubella in this country. So where is the moral imperative on parents to vaccinate to protect these unborn children? The mothers can give protection, simply by ensuring that they have themselves been vaccinated.

What if the child catches rubella herself when older? Shouldn’t she be immunised now to avoid that risk? Well, no. There is absolutely no reason why she could not be immunised at a later date – when she is considering pregnancy or, at least, is old enough to make up her own mind.

The WHO itself recognises that in order to prevent CRS a strategy of immunsing adolescent girls or women of childbearing age is perfectly adequate.

I believe that it follows from the points made above that there is no real moral or medical case for immunising babies against rubella. The vaccination is thought to be very safe, which is perhaps why it is universally given as part of the MMR vaccine. That does not make it necessary.