The Department of Health advises that all children should receive the two-dose MMR vaccine. The first dose is given between 12 and 15 months; the second, a booster, is given between 3 and 5 years. The first injection confers immunity to 90 per cent of those who receive it, the double dose raises this to 99 per cent.

The WHO recommends coverage of 95 per cent to prevent outbreaks; in the UK, about 81 per cent of children are vaccinated by the age of 2, although the figure is creeping upwards again.

Single vaccinations — which became popular after the MMR triple vaccine was rumoured to be linked to several cases of bowel disease in children with autism — are not licensed for use in the UK and parents are cautioned against having their children immunised in this way.

The single-vaccination route requires six separate injections; health officials say that this route is more risky because there is less research on its effectiveness, and because children are left vulnerable between jabs. Other research also shows that single-vaccination courses are less likely to be completed.

The research that caused the furore has been discredited, and many epidemiological studies have confirmed that the MMR vaccine is safe. The Government’s refusal to support single vaccines, because of the existence of the safer alternative of MMR, is widely supported by the medical profession.The MMR jab can be administered at any age, and can also be given to children who have had some or all of the single vaccines. Parents who now wish their child to receive the MMR vaccine should consult their GP or health visitor.