TWELVE years ago, Andrew Wakefield, a doctor at the Royal Free Hospital in London, published a paper pointing out that some children who had been vaccinated against three childhood diseases—measles, mumps and rubella—promptly developed inflammatory-bowel disease and autism. Alarmed parents duly began to refuse MMR jabs for their offspring and cases of the diseases soared. On May 24th Dr Wakefield was at long last banned from working as a doctor, not for reaching the conclusions he did but for the way in which he reached them.
The protracted episode illustrates how public health scares wax and wane. The paper that Dr Wakefield co-wrote, published in the Lancet in 1998, was not greeted with widespread alarm: the study was speculative and small. What breathed life into the story was the birth of a boy who lived in Downing Street. When Leo Blair's parents refused in 2001 to reveal whether he had had the MMR vaccine, newspapers—which are generally in the business of selling copies rather than accurately portraying risks—were suddenly filled with heart-wrenching stories of sick children. The contamination spread: the American Congress held hearings on why rates of autism had risen; and vaccination rates fell not only in Britain but also across much of Europe.
British parents who could afford it frequented plush Harley Street clinics to have their toddlers immunised with three separate jabs, as Dr Wakefield had recommended. The many who could not shunned the triple vaccine, leaving their children and communities vulnerable to disease. In 1998 around 88% of two-year-olds had the MMR jab; in 2003 80% did—well below what is known as the “herd-immunity threshold”, the point at which an epidemic can take hold.
Measles is the most serious of the three illnesses. According to the Health Protection Agency, which monitors infectious diseases in England and Wales, cases soared from 56 in 1998 to 1,144 in 2009. Cases of mumps (which is unpleasant but rarely fatal) ballooned from 121 to 7,628 in 2009; in 2005, almost 45,000 people contracted it. Rubella remains relatively rare.
Over time, no link was confirmed between the MMR vaccine and autism, and immunisation rates returned to their earlier levels. The condemnation this week of Dr Wakefield by his peers, for a series of failures including giving his research interests priority over the clinical interests of the children he studied, appears to conclude the matter.
An earlier investigation into the scare, however, led by Ian Hargreaves of Cardiff University, placed the blame squarely on the media, for coverage that “was unintentionally misleading in creating the impression that the evidence for the link [between the vaccine and autism] was as substantial as the evidence against it”. That is unlikely to prevent future scaremongering. On May 17th studies from 13 countries concluded that no clear link could be established between mobile-phone use and brain tumours. They provoked headlines saying just the opposite.