What factors influence measles, mumps and rubella vaccine hesitancy among parents? A systematic review

Measles, mumps and rubella (MMR) are infectious diseases that can lead to severe complications including disability or death (Demicheli et al, 2012). Measles in particular is a highly contagious viral disease affecting both children and adults (Public Health England (PHE), 2019a) with unvaccinated children under the age of 5 years being most at risk of harm because of their vulnerability (World Health Organization (WHO), 2020).

Prior to the introduction of the MMR vaccine in 1988 (PHE, 2019b), major outbreaks of measles were seen every few years, resulting in millions of deaths each year (WHO, 2020). Since the vaccine's introduction, death rates have declined; however, in 2018, measles surveillance saw a rising trend of cases across Europe and led to the UK losing its ‘measles free status’ in 2019 (WHO, 2019). According to Demicheli et al (2012), fatalities are more commonly seen in countries with higher levels of deprivation and less advanced healthcare systems; however, the risk remains in any country, regardless of wealth. MMR, like many other infectious diseases, are preventable with vaccination, a cost-effective method of protecting the public and preventing ill health. The childhood immunisation schedule recommends two doses of the MMR vaccine: the first at 12 months old and the second at 3–5 years old, to ensure that those with a poor response to the first vaccine achieve an adequate level of protection (PHE, 2019a; b). The current MMR vaccination uptake for first vaccines in under 5-year-olds is high at 94.5%; however, uptake of second doses has fallen to 86.8% and the negative effect of social media has been linked to non-acceptance of this vaccination (Nuffield Trust, 2021).