Bellaby, P. (2003) ‘Communication and miscommunication of risk: understanding UK parents' attitudes to combined MMR vaccination’, British Medical Journal, 327, 27 September 2003, pp. 725–28. Reproduced by permission from the BMJ Publishing Group; Mary Evans Picture Library Ltd; P A Photos.
In 1998 Wakefield was the first to make the claim that autism and the MMR vaccine are linked.1 It is based on a dozen clinical cases of gastrointestinal disorders with which developmental regression seemed to be linked. They arose in previously normal children. His team found that eight of the 12 parents attributed the onset to the MMR vaccination. On a population level, diagnoses of autism increased rapidly from 1988, when MMR was introduced, and through the 1990s, not only in Britain but also in North America. Yet epidemiologi-cal studies have found no link between increasing numbers of diagnoses of autism and the Introduction of MMR vaccine.2, 3 The weight of scientific opinion is that the risk is insignificant.
By contrast, there is both laboratory and epidemio-logical evidence for the transmission of BSE from cat-tle to humans. Consumption of mechanically recovered meat, common among children, has been implicated.4 The risk is considered real but small. Brown et al estimate 10–15 cases a year from its first appearance in 1994, eight years after BSE was identified in UK cattle,5 and Ghani et al suggest that the primary epidemic in the known susceptible genotype began to decline in 2001.6 It seems that the outbreak of
BSE that led to vCJD abated long ago, and no further cases are likely to be incubating.
Injuries incurred in road transport crashes by children (ages 0–15 years) are easy to demonstrate, common, and recur year on year. In 2002 there were 34 689 casualties from road crashes in Great Britain, of whom 4596 received serious injuries or were killed.7 Children (like elderly people) are relatively vulnerable as pedestrians. They are also prone to cycling injuries. But about 45% of child road casualties are car passengers (more than 70% for those aged under 2 years). Although the overall number of casualties from road crashes continues to decline, children are progressively more likely to travel by car and less likely to walk or cycle, even to get to school.8 This is one of the factors implicated in the decline of exercise and increasing obesity in children.