With more than 20 Covid-19 vaccine trials happening around the world, scientists are working flat out to find a preventative measure for coronavirus, which could put an end to the wave of lockdowns, deaths, and hospitalizations gripping our world. 

Most scientists agree that finding a safe, effective vaccine — as quickly as possible — is the only viable path out of the pandemic. But the number of people reassured by any future Covid-19 vaccine’s safety is dwindling. Only 50% of Americans would be willing to get injected with an FDA-approved vaccine, an October Gallup poll found, a worrying 11-point dip from last month. The numbers vary by country — while in China, 97% of people say they would take a vaccine, in parts of Europe the skepticism is on par with the U.S., with almost half of respondents in Poland and Hungary saying they would spurn the vaccine.

Among Facebook’s massive anti-vaccine groups, and in conspiracy forums on other online platforms such as Instagram, 4chan and Twitter, the same grievances are emerging over and over again: that the vaccine will be rushed into completion, and will therefore be dangerous.

“Vaccination has been a controversial issue for a long time, even for established vaccines with a wealth of scientific evidence supporting their efficacy and safety,” said Karen Douglas, a professor of social psychology at the University of Kent. “A brand new vaccine is bound to cause some concern, and many people will naturally want to wait to see how it works and if it is safe.”