The research that led parents to doubt whether to vaccinate their children has today, finally, been retracted. In 1998, Dr Andrew Wakefield and others published a speculative study in the prestigious British medical journal The Lancet, associating behavioral and intestinal problems in eight children with the measles mumps and rubella (MMR) vaccine.
But no other researchers have replicated his results, and finally The Lancet's editors have retracted the paper, something they should have done back in 2004 (or preferably they should have never published the paper). Numerous flaws--including a small sample, no control group, and unresolved reverse causality (the vaccine is given around the same age that autism is generally diagnosed)--led 10 of the study's 12 authors to recant in 2004, saying "no causal link was established between MMR vaccine and autism as the data were insufficient." But still Dr Wakefield kept campaigning.
It's been a bad week for Dr Wakefield, since he was censured by Britain's General Medical Council for a whole slew of charges relating to ethical infractions, and generally poor behavior for a researcher using human subjects, in this case children.
More important and more dangerous than Dr Wakefield's strife is that he convinced many parents to stop vaccinating their children: the result is at least a ten-fold increase in measles in UK alone. And today, steadily weakening vaccination coverage in Britain and four other countries is undermining efforts to eradicate measles across Europe and increasing the threat to the United States.
As I noted last year:
In the United States, the vast majority of the measles reported "were imported from or associated with importations from other countries, particularly countries in Europe, where several outbreaks are ongoing," says the U.S. Centers for Disease Control. "Measles is one of the first diseases to reappear when vaccination coverage rates fall," CDC also noted.
EUVac, a European network for tracking vaccine-preventable diseases, found Europeans have also taken measles to South America, which was previously free of the disease. EUVac blamed Britain, Germany, Romania, Switzerland, and Italy. Europeans have taken measles to South America, which was previously free of the disease.
The MMR vaccine has cut death from measles worldwide from roughly 750,000 in 2000 to 197,000 in 2007, according to the World Health Organization. Two-thirds of the reduction was in Africa, where deaths dropped by 89 percent. In rich countries, measles is often viewed as a nuisance--indeed, there were only seven deaths in Europe out of 12,132 cases in 2006 and 2007, according to EUVac. However, such a statistic hides the long-term consequences of the disease and the suffering it creates. Even if measles does not kill you, it can cause pneumonia and miscarriage. Rubella can cause miscarriage or stillbirth and can leave surviving children with heart defects, deaf-blindness, and other organ damage. Before the introduction of the MMR vaccine in 1969, mumps was the most common cause of viral meningitis. Mumps can also cause encephalitis in children and young adults and can sterilize men.
Despite the importance of vaccination to healthy children and adults, the commitment to vaccination in the West is weakening, due to the MMR controversy. Nearly a quarter of children in Britain are not getting the two doses required for total immunity.
Dr Wakefield must take most of the blame for this fiasco, but The Lancet editors deserve some too. At issue is how a journal treats new and explosive findings. Studying potentially dangerous practices, from smoking to occupational hazards, such as carcinogens in factories, required epidemiology to establish the link – in much the same way Dr Wakefield tried for the MMR. But he didn't follow most of the guidelines (written by Sir Austin Bradford Hills) for finding a likely causal relationship between two factors – his sample was tiny, he could not explain a plausible biological link, and his subjects were self-selected with no controls, all major factors, which should have led The Lancet editors to reject the paper and ask for further evidence before publication.
We need academic risk takers prepared to take a chance of going against establishment thinking, but they should play by the scientific rules, because the result when they don't can be fatal.
Roger Bate is the Legatum Fellow in Global Prosperity at AEI.