Vaccination and autism: the link is still missing

Between January and July of this year there were more cases of measles in the United States reported to the Centres for Disease Control and Prevention in Atlanta, Georgia, then at any time since 1996. This is a worrying statistic, and all the more so since it is being attributed to parents refusing to have their children vaccinated because of fears of a link between vaccinations and autism. This is an issue that has been gaining momentum for many years and it is unlikely to go away any time soon. Moreover, the situation is not limited to the United States. Parents' worries have quickly spread to other countries.

The consensus among the medical fraternity is that all vaccination programmes should remain in place, and although health professionals continue to try to alleviate parents' fears, that does not appear to have had an effect. This could be disastrous if a solution is not found, public health officials warn. Measles is a barometer for other diseases that may follow in unvaccinated populations. A rise in the number of cases of mumps and rubella could follow the spike in measles cases, doctors say.

Any link between vaccinations and autism in children has never been scientifically proven. Yet, as some autism research groups are eager to point out, there has never been categorical evidence to disprove the link either. The foundation for the entire vaccine-autism debate rests on a scientific paper published in The Lancet in 1998, in which lead author Dr Andrew Wakefield suggested the possibility of a link between the MMR (Measles Mumps Rubella) vaccine and certain cases of autism in children.

The work carried out by Dr Wakefield has never been replicated and he has even been accused of scientific misconduct. Although overall a growing body of data supports the 'no link' camp, this is an issue that will not go away. In an attempt to allay public fears, manufacturers of the MMR vaccine in the United States reduced the level of mercury as an ingredient of the product. The change was instituted seven years ago and now appears to have had little effect on reducing incidence of autism. But it could be argued that by doing this the public became more suspicious about this vaccine. After all, why tamper with a product that you are claiming is completely safe?

The situation became further complicated when earlier this year a leading physician at the centre of health policy in the United States made a claim about the possible susceptibility of some children to autism from vaccine jabs. Dr Bernadine Healy, the ex-head of the US National Institutes of Health, in an interview with CBS in May, is quoted as saying: "What we are seeing is that, in the bulk of the population vaccines are safe, but there may be a susceptible group."

Dr Healy has suggested that studies being carried out might be missing crucial factors that may offer a possible link between vaccinations to autism in a small group of individuals. Or rather, because this type of research is being overlooked any link cannot be discounted. Indeed part of her claim is that as part of the research, the Institute of Medicine (IOM), as far back as 2004 was allegedly looking to avoid seeking patient groups who might be susceptible. The reason for this was put down to public safety concerns by the IOM.

Critics claimed that the institute feared that if the slightest suggestion of research offering a link between vaccinations and autism was revealed, the knock-on effect would be masses of parents refusing to have their children immunised, with serious consequences to long term public health. Although for some this might be construed as a legitimate reason, the outcome has backfired in spectacular fashion, at least in the United States. Elsewhere, vaccination programmes are administered as planned, including in the UAE.

Mohammad al Emadi, the Director General of the Dubai Autism Centre, feels a level of bemusement over the current situation in the United States. "We've noticed that the people who are talking about this are in America," he said. "Around the world this isn't happening. You can't really say that's the proof that causes autism. There have been exercises that have removed the vaccinations and still the cases of autism are there."

Mr Emadi indicated there is no single factor relating to why a child will become autistic, and there is continued research to explain its exact causes. "You can't say it's the environment, you cannot say it's genetic, you can't say it's because of a food allergy, or that it's a vaccination. It is multiple entries. Autism can come from anywhere," he said. "Each child has a different autism and they've got it from a different place. Some have got it from an infection in the ear; some have got a very high fever... You cannot say this is the cure and this is the problem," he concluded.

Mr Emadi believes that decisions can only be made once adequate research indicates the root causes of autism, echoing a view shared by the majority of policy-makers and medical professionals. Yet, as long as the debate continues to rage in the United States it could spread to other countries quickly. First and foremost, parents worry about the health of their children, and if there are any doubts about the safety of vaccines in the long term this will have a massive bearing on how successful that vaccination programme will be.

Whether it is in the United States or the UAE, a solution has to be found for the problem at hand: how to adequately provide a vaccination programme that protects children while alleviating the fears of the public. Peter Donnelly is a science correspondent with the Life Science Division of IIR Middle East.