The combined measles, mumps, and rubella immunization has been used in the UK since 1988. It is generally administered to children at the age of one year, and is continued in a booster several years later. Uptake of the second shot is much lower than the first, but it is necessary for adequate protection from disease. Single antigen vaccines are also available, but are not licensed for use in the UK, and are only available on a private basis.
Research published in 1998 suggested a link between the vaccine and autism and bowel disease, and rates of vaccination fell from 92% in 1995 to 79% in 2003. Although MMR uptake rates have increased recently, more cases of the measles were reported in 2007 than for any year in the past decade.
Investigators at the UCL Institute of Child Health and the Great Ormond Street Hospital for Children found that, by the age of three, 88.6% of children had been immuzied with MMR. Additionally, 5.2% had received at least one of the three individual vaccines, and 6.1% were not immunized. Of the children with at least one single vaccination, just over half had received all three.
The researchers also explored the social, economic, and cultural factors that went into uptake, and the parents' reasons for omitting the MMR vaccine. For this, focused on uptake of the first dose of MMR. Children without MMR immunization were more likely to: come from a large family, have a mother who smoked, and have a mother who was younger than average (under 20 years) or older than average (more than 34 years) at the time of birth. In comparison with the full immunization, parents who chose single vaccines were more likely to be white, well educated, wealthy, older, and have single children. Parents who chose not to have their child immunized overwhelmingly (74.4%) stated that it was a "conscious decision," often citing general fear, an impression that the vaccine was dangerous, the purported link to autism, and negative media attention.
Although the MMR vaccination rates in this study were high, the authors stress that this is far below the level necessary to prevent disease outbreak. A substantial proportion of children still remain at risk for avoidable infection -- for the most part, this is because parents consciously decide against immunization. Additionally, the single antigen vaccines are not considered a good substitute for the combined MMR vaccine. The authors conclude that improvement in this area is essential, and to achieve most effective control of these vaccine preventable diseases, many different measures should be used to target the low uptake groups.
Factors associated with uptake of measles, mumps, and rubella vaccine (MMR) and use of single antigen vaccines in a contemporary UK cohort: prospective cohort study
Anna Pearce, Catherine Law, David Elliman, Tim J Cole, Helen Bedford
BMJ, published 28 February 2008
Written by Anna Sophia McKenney