It isn’t just anti-vaccine conspiracy theorists who are reluctant to get COVID-19 vaccines: In one recent survey, nearly half of Americans said they were hesitant to get vaccinated. Only 53% said they would be willing to do it; of the rest, most said they thought the vaccines were untrustworthy. But if at least 70% of the population doesn’t get the shots, it will be difficult to get the virus under control. Here’s why experts say that you should be confident getting vaccinated.
One common concern skeptics have is the fact that the first vaccines were developed in record time. But the speed wasn’t a result of cutting corners. The first two vaccines that have been approved, from Pfizer-BioNTech and Moderna, use mRNA technology that had been in development for decades. One of the great benefits of the technology is that it can be adapted quickly. “They were able to leverage that technology that was used for a different therapeutic use,” says Rupali Limaye, a scientist at Johns Hopkins Bloomberg School of Public Health. The mRNA—messenger ribonucleic acid—essentially gives your cells the instructions to make a protein from the coronavirus so that your body can develop an immune response. After your cells get the message, your body destroys the mRNA, so there’s nothing left in your body; it has no impact on your DNA. (It also can’t give you COVID-19.)
The scale of the pandemic led the government to pour billions into vaccines, and also led thousands of people to quickly volunteer to get vaccinated, which also helped the process move much faster than usual. “It takes 10 to 15 years to make a vaccine, typically. . . . It takes that long to find funding and that long to find the number of volunteers,” says Joe Smyser, CEO of the Public Good Projects, a public health nonprofit. It also takes time to determine how well a vaccine works if a disease is spreading slowly, but because COVID-19 has been rampant in the U.S. and so many people have been getting sick, it was possible to see within months that the vaccine was working in volunteers. Vaccine developers were also able to perform parts of their trial simultaneously—without skipping steps—to get results faster. At the same time, the vaccines became available so quickly because manufacturers started making them early, in advance of their anticipated approval, so distribution could begin as soon as they were proven safe.
Both vaccines went through the same rigorous testing as all other vaccines, beginning with trials in smaller groups to look for side effects and determine whether the vaccine spurred an immune response. They then moved on to larger trials with thousands of volunteers. The Pfizer trial included more than 43,000 volunteers and showed that the vaccine was 95% effective. While 3.8% of volunteers experienced fatigue after the second dose, and 2% experienced headaches, there weren’t other major side effects. Moderna’s trial, with 30,000 volunteers, showed that its vaccines were 94.5% effective, again, with only minor side effects, such as short-lived fatigue, muscle pain, headache, and achiness.
It’s true that the trials didn’t reveal every possible impact from the vaccines. After the trials, when the vaccines were approved for emergency use, a small number of people who were vaccinated experienced allergic reactions. “The trials enrolled a diverse group of people,” Limaye says. “But that does not mean that we will see any possible reaction that could or could not be associated with the vaccine. Different people react to any product differently.” The Centers for Disease Control and Prevention recommends that anyone with a history of serious allergic reaction to other vaccines should talk to their doctor, but those with other types of allergies should get vaccinated.
Some people are worried that because the vaccines are new, it’s possible that some long-term side effects could later be discovered. While there is obviously no way to know that now, there is some historical data to look at. “We do have the history of all these other vaccines that we have been given for a long, long period,” Limaye says. “And we have seen that very few of them have any sort of long-term side effects.” She compares getting vaccinated to taking other medications with side effects: The risk of an adverse reaction has to be weighed against the very real risk that someone who isn’t vaccinated may get COVID-19 and become very ill or die.
Some people may also be hesitant because they worry that the vaccine development was politicized. “The communication about the vaccines was put out by an administration people knew to be spreading a lot of misinformation,” Smyser says. “That had a halo effect over anything that was vaccine-related. And I think people are now just very unclear about what to believe and what not to believe.” Others might worry that the drug companies making the vaccines are themselves untrustworthy. But the data from the trials went through rigorous independent review.
Now it’s possible that the chaotic rollout of the vaccines throughout the states is also adding to overall hesitation. “I think it becomes compounded because now that there are products on the market, there’s not enough supply, and the challenges with logistics and distribution are, I think, undermining confidence in the product itself,” Limaye says. The more people hesitate—combined with the slow rollout—the more we lose time in the fight to get the virus under control, and the more risk there is that more contagious, potentially more dangerous new variants will spread and continue to mutate.