Why People Reject Vaccination—and How to Change Their Minds

As of early December, about 8.5 billion doses of COVID-19 vaccine have been administered worldwide. That makes the COVID-19 vaccination effort easily the largest public health intervention in history—and yet, its success has been mixed. The world’s most vulnerable countries have been denied their fair share of vaccination doses, while in wealthier countries, the main problem is not access but hesitancy, often concentrated in specific regions of anti-vaccination sentiment. For example, the eastern German state of Saxony has full vaccination rates of only around 56 percent, and an infection rate more than twice as high as the country as a whole.

Much of the discussion around COVID-19 vaccine hesitancy has focused on how different the COVID-19 vaccine is from other vaccines—for example, no other vaccine has been developed as quickly. But to view COVID-19 vaccine hesitancy as a new phenomenon neglects the meteoric rise of broader anti-vaccination sentiment worldwide over the last few decades. 

There may be no better illustration of this concept than the measles vaccine. As an extraordinarily contagious disease, measles requires a vaccination rate of around 95 percent to achieve herd immunity—the point at which the disease won’t circulate through the population freely. In 1978, after the year before the first dose of the measles vaccine was introduced in Romania, 540 out of every 100,000 people contracted measles. By the turn of the millennium, child vaccinations had hit 96 percent and incidence in Romania had reduced to 0.16 per 100,000 people—a tremendous accomplishment by any standard.