FOR COUNTRIES with lots of covid-19 vaccines, the most important task is convincing people to get jabbed. In America most adults who want the shots already have them, leaving an unvaccinated population full of hardline refuseniks. France, where scepticism about vaccines has long been high, will soon require vaccine passports for entry at restaurants and cinemas.
Fortunately, hesitancy has been falling steadily. YouGov, a pollster, has run surveys about vaccination in 20 countries. Counting each country equally, in January around 45% of respondents said either that they would not get a shot or that they were unsure. By late June just 20% did.
Identifying the cause of this dip is hard because hesitancy has declined almost everywhere. However, the drop has been unusually steep in some places. Moreover, within countries, the rate of change in hesitancy has varied from month to month.
Among the many factors that could change sceptics’ minds, two can be measured readily with national statistics. One is the pace of vaccination. The more doubters see that shots are available and that people they know have not suffered ill effects, the more willing they may be to follow suit. The other is the gravity of the pandemic. If lots of people are dying, fear of the virus might trump fear of the vaccine.
To assess these variables’ impact, we built a model of vaccine hesitancy. For each of YouGov’s polls, we calculated the gap between the result and the country’s average hesitancy in 2021. We then measured how much each country’s rates of new vaccinations and covid-19 deaths on the date of the poll differed from its overall averages. Next, we tested to see if hesitancy fell faster than the global average did at times when rates of deaths or vaccinations were unusually high, by countries’ own standards. We also checked if hesitancy in January affected the pace of decline later on.
Whereas starting hesitancy levels had no effect, vaccinations and deaths were both strong predictors. Vaccinations mattered three times more, a pattern that is clearest in places the pandemic has spared.
For example, covid-19 has killed just 36 people in Singapore so far. Nonetheless, the share of people there expressing hesitancy fell from 53% in December to 10% in June. The sharpest declines in hesitancy occurred just as vaccinations revved up. Another case is France, where the share of respondents who said they would or might refuse a vaccine dropped from 60% in January to 20% in July. During this period, a majority of French adults got vaccinated, and the daily death toll fell from 300 to 20.
However, deaths have had a greater impact in some places. For most of 2021, hesitancy in Taiwan was common, reaching 66% in April. Taiwan had also fended off the pandemic, with just 12 deaths by May 16th. Since then, however, over 700 people have died. And no sooner did a serious outbreak begin than hesitancy plummeted. It reached 27% on June 3rd, long before vaccinations ramped up. Deaths were also probably a driver of falling hesitancy in Saudi Arabia, where most of the decline occurred amid rising mortality from March to May.
No country wants to imitate Taiwan, reducing hesitancy only as deaths rise. Supplies permitting, rolling out vaccines early can help sceptics overcome their doubts. However, as America’s vaccination slowdown shows, supply creates its own demand only up to a point. Flipping fervent anti-vaxxers may require sterner tactics.■
Sources: YouGov; Our World in Data; The Economist