Does MMR lead to bowel disease and autism? How do you weigh up the risks of immunisation against the risks of measles, mumps and rubella? Jane Bartlett on the dilemma facing all new parents

Despite loud reassurances from the Government about its safety, many parents are now refusing the MMR jab, routinely given to children at 12–15 months followed by a booster at 3–5 years. The chief medical officer, Liam Donaldson, is so concerned that he’s holding talks with leading doctors and nurses to discuss how to reverse the decline in uptake of the MMR injection.

There are those treading a middle path and requesting that the triple vaccine is administered in single doses, believing it may be safer. The NHS is reluctant to go down this road but the really committed are travelling abroad to find private clinics with single vaccine stocks (which are in short supply on the NHS) and paying up to £250 for treatment. All this and now we’re being told by the Government’s public health officials that there is a growing risk of a measles epidemic. What’s a parent to do?

The history of MMR

A possible link between Crohn’s disease and the MMR vaccine was raised in 1995, following the publication of research carried out by Dr Andrew Wakefield at the Royal Free Hospital in London. This research compared the incidence of Crohn’s disease (a bowel disease) in a group of people who had received the measles vaccine in 1964 with the incidence in two other groups. An association was found, but the researchers also said that there wasn’t necessarily a causal relation. Two later studies in 1997 showed no link between MMR and Crohn’s. Another study found no link either between Crohn’s and measles infection before birth. In 1999 another British study linked the MMR vaccine to autism, but this was widely criticised by researchers as being small and of poor quality. Then in January 2001, a major Finnish study was published. It followed three million children who had received MMR and apparently gives the vaccine a clean bill of health.

Others however are not convinced. About 2,000 families in Britain are taking legal action because they believe their children have been damaged by MMR, many saying that it has led to autism. Pressure groups claim there are many cases in which healthy children fell ill immediately or shortly after they received the MMR vaccine. Worried parents say they would rather risk measles, the side effects of which can range from a two-week spotty infection, to autism, a serious and life long communication disability.

The medical establishment is also divided. The British Medical Journal reports (January 13th 2001) that nearly half of family doctors, health visitors and practice nurses have reservations about giving children their second dose of MMR.

Warnings of a measles outbreak

Such has been the concern over MMR many parents have refused to have their children vaccinated. Uptake rates, which stood at 92% in 1992 have now fallen to 75% in some parts of the country. Other parents are requesting that the triple vaccine is administered to their children in single doses. This can mean a time delay in the immunisation schedule and reduced protection. As a result, the Government’s public health scientists warn that measles is making a comeback. There is already an increase of measles in Ireland, where two babies recently died of the infection. The vaccine can prevent measles in 90% of all immunised children, and a second dose raises protection to 99%.

How dangerous is measles?

The comic depiction of a spotty-faced child belies the fact that measles can be serious. These are the facts:

• Before a vaccine was developed this highly infectious viral illness was common in Britain, and every year it took lives and left children permanently disabled.
• Most children recover well, but for a few there are complications including infection of the middle ear and bacterial pneumonia, both of which can be treated with antibiotics.
• In about 1 in 1,000 cases, encephalitis occurs, an inflammation of the brain, which can cause long-term brain damage.
• A rare complication of measles is subacute sclerosing panencephalitis (SSPE), which causes the destruction of the nervous system and death. The measles virus can stay dormant for seven years and be reactivated later, causing this catastrophic condition.
• Between 1970 and 1989 in England and Wales, SSPE occurred at a rate of 4 per 100,000 cases of measles.
• Children whose health is already compromised in some way are at a greater risk from measles.

Symptoms of measles

• First symptoms include runny nose, sore eyes, a cough and fever.
• Around the fourth day a rash may appear – flat red or brown blotches – usually starting on the forehead and spreading downwards.
• There may be diarrhoea, vomiting and stomach pain.
• Some children shy away from light.

Campaigning parents’ organisations like Jabs (Justice, Awareness and Basic Support) claim that single component vaccines are less risky and should be offered by the NHS. It is only the combined vaccine that has been linked to autism and bowel disease.

The Government does not support single component vaccination. It believes this approach is counterproductive because the gaps between jabs put children at a higher risk of infection. In Japan, where the vaccinations are administered separately, 79 people died from measles between 1992 and 1997. Another consideration must be that it will cost the NHS a lot more money to immunise children in single doses. Cynics believe this is the real reason for their intransigence.

How do parents weigh up the risks?

Thanks to the vaccination programme we now live in a society where it is rare to have, or know of, a child who dies from a contagious illness. Those who support MMR believe that we have lost sight of how dangerous infections like measles can be.

The weight of evidence points to the MMR vaccine being safe, but in the face of these reassurances parents are still worried. So have we lost trust in the scientific and medical community? They often get it wrong and what is recommended one week can be cautioned the next.

MMR immunisation is not risk-free. Single component vaccination is not risk-free. Not having your child immunised at all may be even more chancy. It’s worth bearing in mind that currently there is no conclusive proof that MMR is unsafe, but we do know with certainty that children die each year from measles. Deciding what to do seems to be all about risk management, and hoping for the best.