Parental understandings of MMR vaccination and the MMR controversy
Two hundred years after Jenner’s observations on the protective effect of cowpox on smallpox, the success of mass immunisation has contributed to the decline of many once-common infectious diseases; paradoxically, as people have less experience of these diseases they have again become more concerned about the safety of immunisation. Such concerns were evidenced after the publication of Andrew Wakefield’s Lancet paper in 1998 on the safety of the measles, mumps, and rubella vaccine (MMR). Uptake rates fell from 92% before the controversy to around 80% in some parts of the UK by 2003/04. To investigate parental understandings of the evidence on MMR safety we conducted eighteen focus groups (representing a diverse range of ages, socio-economic backgrounds, family circumstances, and previous vaccine decisions) in 2002/2003.
We found many gaps in knowledge about some vaccine-preventable diseases, most notably diphtheria, tetanus, and haemophilus influenzae type b, three of the diseases covered by the pentavalent vaccine introduced into the UK Childhood Immunisation Programme in 2004. These gaps led some parents to be doubtful about the need for vaccination. Poliomyelitis and diphtheria were no longer seen as a threat to children’s health in the UK, and some parents viewed mumps as only relevant for boys’ health and rubella as only being relevant for girls’.
We also identified a further factor in decision-making about vaccination: parents’ assessment of their children's immune system’s ability to ‘cope’ with the challenge of combined vaccines. Parents referred to two closely related terms, ‘immune-overload’ and ‘immune-vulnerability’. ‘Immune-overload’ was used as a generic term to describe the immune system being ‘overwhelmed’ by receiving too many antigens in too short a time at too young an age. ‘Immune vulnerability’ was used to describe how well their own child’s immune system could cope both with the antigens contained within the vaccines and the invasion of other pathogens. Recurrent colds, ear, chest and urinary tract infections, and chronic conditions such as eczema, asthma, and allergies were often cited as evidence that a child might have a ‘deficient’ immune system. Some parents expressed concern that such a ‘deficient’ immune system could render a child more vulnerable to potential harms of the MMR vaccine.
These findings suggest there are still challenges to overcome in communicating information to parents about vaccine-preventable diseases. However, an even greater challenge exists in reversing a decline in public trust in politicians and health professionals (also observed in our earlier work on BSE, heart disease etc). We found considerable uncertainty about whom people could trust to offer balanced and accurate information; politicians were seen to be untrustworthy in matters of health, and the motives of primary health care staff were questioned by some parents, who saw them as having vested interests (including financial) in promoting vaccination. Andrew Wakefield, whose publication fuelled the MMR controversy, was viewed by some as an important ‘whistle-blower’ and champion of ordinary parents. Providing accurate information is insufficient in helping parents make well-informed immunisation decisions; establishing and maintaining trust in the information provided is also crucial.
Much of the focus of the MMR controversy was on whether the vaccine might be linked to the onset of autistic spectrum disorder. We undertook additional focus groups with parents caring for children with autism, and found that some experienced “agonising uncertainty” as to whether the MMR vaccine may have provoked their child’s autism, and many wondered whether they were to blame for their child’s condition by deciding to vaccinate. The discussions also showed that most parents found it extremely difficult to make subsequent decisions about further vaccination for their children with autism or other children within the family. Many parents also felt let down by health professionals.
Hilton S, Hunt K, Petticrew M. Gaps in parental understandings and experiences of vaccine-preventable diseases: a qualitative study. Child: Care, Health and Development 2007;33:170-179pubmed open access
Hilton S, Hunt K, Petticrew M. MMR: marginalised, misrepresented and rejected? Autism: a focus group study. Archives of Disease in Childhood 2007;92:322-327pubmed open access
Hilton S, Petticrew M, Hunt K. Parents' champions vs. vested interests: who do parents believe about MMR? A qualitative study. BMC Public Health 2007;7:42pubmed open access
Hilton S, Petticrew M, Hunt K. Combined vaccines are like a sudden onslaught to the body's immune system: parental concerns about vaccine overload and immune-vulnerability. Vaccine 2006;24:4321-4327pubmed
Hilton S. Parental perceptions of childhood immunisation in the context of the MMR controversy [PhD], MRC/CSO Social and Public Health Sciences Unit 2005.