People would say, ‘I’m going to get the vaccine, but I’m not going to be the first one. I’ll be in the second wave. I don’t want to be the guinea pig.’ —Ashley Wenaas, MD
Explore This IssueJanuary 2021
Pfizer and BioNTech’s vaccine was found to be safe and 95% effective at preventing infection, and particularly at preventing severe cases. Moderna’s vaccine has also been found to be safe, with a 94.5% efficacy in preventing infection, and, like Pfizer’s, highly effective at preventing severe COVID-19 cases.
A vector vaccine being developed by AstraZeneca contains a weakened version of the live virus that carries genetic material from SARS-CoV-2 into cells. That genetic material prompts production of the spike protein, instigating an immune response. Johnson & Johnson has also developed a vector vaccine, which, as of December 2020, was being assessed in a trial. Sanofi and Novavax are running separate trials to test the efficacy and safety of a protein subunit COVID-19 vaccine.
Even as Operation Warp Speed fed billions of dollars to pharmaceutical companies to manufacture the vaccines, those vaccines were still being studied to see whether they would be safe and effective. Infectious disease experts said the accelerated timeline has been the product of urgency, funding, and raw will—but not through an abandonment of the scientific process.
“Necessity is the mother of invention, and there’s a huge need here,” said Kenneth Alexander, MD, PhD, chief of infectious diseases at Nemours Children’s Health System. “Although this is being done on an accelerated schedule, the researchers aren’t taking shortcuts.” In addition, the sheer number of people in the studies—tens of thousands—should be reassuring. “If you examine the mathematics, an undetectable side effect would have to happen in the neighborhood of 1 in 10,000 people or fewer,” he said.
Despite this rigorous process, the U.S. population is split in its views of COVID-19 vaccines. Survey data released from the Pew Research Center in September 2020 showed that 51% of U.S. adults said they would definitely or probably get a vaccine, while 49% said they would definitely or probably not get one.
Those percentages have been fluid: Earlier, in May 2020, 72% said they would be at least likely to receive a vaccine. But after the September drop, more recent poll results, released in December 2020 by the Kaiser Family Foundation, found that 71% of respondents would definitely or probably get a vaccine.
Dr. Hotez believes the number of people who would get a vaccine will increase as the rollout continues. “I think a large part of that [hesitation] could evaporate as people start to get vaccinated and see no untoward effects,” he said. “I think there’s a group that is concerned about all the politicization they’ve seen in regard to the COVID-19 vaccines. With adequate communication, that part can be fixed.”