The MMR vaccine – which acts against measles, mumps and rubella – is introduced in the UK. It has been used in the US since 1971
The gastroenterologist Dr Andrew Wakefield, then of London's Royal Free hospital, proposes measles jab causes Crohn's disease
Uptake rate of MMR vaccine peaks at 92%
Wakefield suggests a link between the MMR vaccine and an increased risk of autism and bowel disorders. He says his team have found a "genuinely new syndrome" and suggest the combination might be overpowering the body's immune system.
The Medical Research Council says there is no evidence showing a link between the MMR jab and bowel disease or autism
Finnish scientists find no danger associated with the MMR vaccine, after a 14-year study
Research published in the Lancet from the Royal Free Hospital, where Wakefield did his research, finds no evidence for MMR and autism link
Wakefield and the pathologist Prof John O'Leary, of Coombe Women's hospital in Dublin, present research to the US Congress. Their study shows that tests on 25 children with autism reveal 24 had traces of the measles virus in their gut. The Department of Health says the findings prove nothing.
Andrew Wakefield resigns from the Royal Free and University College Medical School
The Daily Mail and other papers launch campaigns backing Wakefield
Then prime minster Tony Blair refuses to reveal whether his son Leo has been given the MMR vaccine. Seven years later, Cherie Blair reveals that Leo was given the vaccine
A study by the British Medical Journal finds that autism has continued to rise despite MMR administration being static
A review of previous research, conducted by the MRC, finds no link between the vaccine and autistic spectrum disorders
Wakefield and O'Leary publish a paper in the journal Molecular Pathology, that suggests a link between the measles virus and bowel disease in children with developmental disorders
A large number of scientific studies find no link between MMR and autism including research published in British Medical Journal, New England Journal of Medicine, Pediatrics and Lancet
An investigation by journalist Brian Deer for The Sunday Times exposes the flawed scientific basis for Wakefield's claims, and reveals conflicts of interest which suggest Wakefield could have profited financially by the scare
Ten co-authors on the 1998 Wakefield Lancet paper issue a retraction and editor of the Lancet says, with hindsight, they shouldn't have published the paper
Uptake of MMR vaccine falls to 81%
Japanese scientists say the MMR vaccination is unlikely to be linked to an increase in autism after they find a rise in the condition following the withdrawal of the MMR jab in that country in 1993
Uptake of MMR vaccine at 84%
A 13-year-old boy becomes the first person in the UK to die from measles in 14 years
US scientists report they have found the measles virus in the guts of autistic children with bowel disease. The research leader, Dr Stephen Walker, adds that the finding does not show that the MMR vaccine caused the condition.
Announced that Wakefield is to face the General Medical Council over charges of professional misconduct
Uptake of MMR vaccine increases to 85%. Department of Health says it would like the vaccine uptake to rise to 95% – a level that would give "herd immunity".
A team from London's Guy's and St Thomas's hospitals study the immune responses from the MMR jab in 240 children, and find no evidence to link it to autism
The Health Protection Agency warns of a measles "epidemic" after cases of the disease exceed 1,000 for the first time in a decade. The agency reports 1,049 confirmed cases in England and Wales during the first 10 months of this year, the highest total since 1995. Dr Mary Ramsay, an immunisation expert at the agency, puts the problem down to "relatively low uptake" of the triple vaccine. She adds there is now a "real risk of a large measles epidemic".
The GMC rules that Wakefield "failed in his duties as a responsible consultant" and showed a "callous disregard" for the suffering of children involved in his research. It also found that he acted dishonestly.
Source: Science media centre