Overcoming ‘vaccine hesitancy’ can reduce the global spread of measles infection
With a 30% increase in measles cases worldwide in 2018, the World Health Organization, in January 2019, included ‘vaccine hesitancy’ as one of the 10 threats to global health this year. The threat from vaccine hesitancy, which is defined as the “reluctance or refusal to vaccinate despite the availability of vaccines”, only appears to have grown more dangerous to public health. After a surge in measles cases in 2018, there have been around 3,65,000 measles cases reported from 182 countries in the first six months of 2019. The biggest increase, of 900% in the first six months this year compared with the same period last year, has been from the WHO African region, with the Democratic Republic of the Congo, Madagascar and Nigeria accounting for most cases. There has been a sharp increase in the WHO European region too with 90,000 cases recorded in the first six months — more than the numbers recorded for the whole of 2018. The infection spread in the European region has been unprecedented in recent years — 1,74,000 cases from 49 of the 53 countries between January 2018 and June 2019. Last month the U.K., Greece, the Czech Republic and Albania lost their measles elimination status.
A 2018 report on vaccine confidence among the European Union member states shows why vaccine coverage has not been increasing in the European region to reach over 90% to offer protection even to those not vaccinated. It found younger people (18-34 years) and those with less education are less likely to agree that the measles, mumps, and rubella (MMR) vaccine is safe. According to a March 2019 report, only 52% respondents from 28 EU member states agree that vaccines are definitely effective in preventing diseases, while 33% felt they were probably effective. More alarming is that 48% of the respondents believed that vaccines cause serious side effects and 38% think vaccines actually cause the disease that they are supposed to protect against. A striking similarity was seen in India too. A 2018 study found low awareness to be the main reason why 45% of children missed different vaccinations in 121 Indian districts that have higher rates of unimmunised children. While 24% did not get vaccinated due to apprehension about adverse effects, 11% were reluctant to get immunised for reasons other than fear of adverse effects. Thus, much work remains to be done to address misinformation. With social media playing a crucial role in spreading vaccine disinformation, the commitment by Facebook to “reduce distribution” of vaccine misinformation will be helpful in winning the war against vaccine deniers. Measles vaccine not only provides lifelong protection against the virus but also reduces mortality from other childhood infections. This is because measles viruses kill immune cells, leaving the child vulnerable to infectious diseases for two to three years.