Knowledge, Attitudes and Opinions towards Measles and the MMR Vaccine across Two NSW Cohorts

"Understanding a parent's knowledge and vaccine literacy is likely to facilitate communication and informed decisions making, ultimately improving MMR uptake."

Fear of adverse events and concerns over vaccine safety are frequently identified as major contributors to vaccine hesitancy, in both Australian and international studies. However, the relationship between parental knowledge and immunisation acceptance in New South Wales (NSW), Australia, populations remains unclear. The aim of this paper is to investigate the knowledge and opinions of parents on the measles disease and measles, mumps, and rubella (MMR) vaccine in 2 location cohorts: one with poor immunisation rates (NSW North Coast), and one with high immunisation rates (NSW Central Coast). Results from this study can be used to inform future interventions addressing vaccine hesitancy among Australian parents.

As outlined in the article's introduction, following fraudulent claims of associations with autism, MMR has been the subject of numerous studies on vaccine acceptance, hesitancy, and refusal. Literature describes 2 general groups of non-immunisers: those with social and logistical barriers, and those with conscientious objection. Australian estimates propose that this latter group represents up to 3.3% of parents. Conscientious objection has been attributed to multiple factors, especially to the actions of an anti-vaccination movement that works, e.g., via the internet and social media, to provide (mis)information minimising the clinical effect of measles while maximising alleged side effects of vaccination.

A total of 201 parents with at least one child aged under 12 years were surveyed in the Central and North Coast of NSW using a questionnaire that was constructed based on the Health Belief Model (HBM) and themes identified by previous research.

Overall, 17 out of the 201 (8.46%) respondents reported that they chose not to immunise their child with the MMR vaccine. Most respondents recognised that measles is a highly contagious disease. The vast majority of respondents were able to identify typical non-specific symptoms of measles such as rash and fever. However, very few could correctly identify any further clinical features, or the potential complications that can arise from the disease. No statistically significant difference was found for these results between immunisers and non-immunisers, which may be a consequence of the low sample size. Non-immunisers were found to be older, had a lower perceived severity of measles, were less likely to agree with the efficacy and safety of the vaccine, and were more likely to have encountered someone who had suffered side-effects of the vaccine.

The researchers reflect on these findings. Some of the salient points:

• In this study, the majority of parents who chose not to vaccinate their child did not change their opinion even after measles infection. Thus, it can be suggested that familiarity with measles may produce complacency among parents and serve as a barrier to vaccine uptake. This is indeed contrary to the hypothesis that lack of familiarity with the disease is partially responsible for the growing aversion to immunisation.
• "It is significant that 2.5% of participants still believe there is a causative relationship between the MMR vaccination and autism....It is concerning that belief in the claim is so persistent, despite repeated international rejection."
• The results of this study demonstrate that there is limited knowledge of the disease among Australian parents and raises the question as to whether parents are sufficiently informed to be making these decisions. Concerned parents often look to the internet as a source of information, rendering them susceptible to the anti-vaccination narrative. This reinforces the important role of healthcare providers as educators.

Along the lines of the latter, based on the findings, the paper goes on to explore the potential for intervention and role of healthcare workers. It looks at some of the strategies that have been used to address vaccine hesitancy. For example, "social media may provide opportunity for 'face-to-face' communication, and parental social networks have been isolated as significant contributors to immunisation decision making....Although the exact method remains to be elucidated, the results of this study suggest that addressing vaccine-related misconception and risk/benefit interpretation should be future targets for intervention."

In conclusion: "Misconceptions about the reality of measles and suspicion over the safety and efficacy of the MMR vaccine continue to be prevailing concerns of the non-immuniser group. It is important that Australian public health groups and primary healthcare providers seek to address these concerns to minimise the burden of non-immunisers on the community. Better means of public education need to be developed. Perhaps the power of 'social media' could be harnessed to this effect."