Since Monday, eagerly awaited Covid-19 vaccines have been going into the upper arms of health care workers around the United States, the first slender tranche of millions of doses to come. But the joy that has greeted the shots’ arrival is already being muted by worries. Billions of dollars were spent to achieve the formulas. Prepping the US population to receive them got much less attention.
This may turn out to be a mistake. The documentation provided by Pfizer and Moderna to the Food and Drug Administration notes that both vaccines have side effects—minor ones that fade after roughly two days, but that occurred in substantial percentages of people who received them in the trials—and a few serious reactions have been reported. Descriptions of those side effects are beginning to circulate, via news reports and also social media accounts written by trial participants.
Those descriptions are reaching the public in the absence of any effort to contextualize or counter them. There has not, to this point, been a coordinated national campaign that reassures people the vaccine not only works, but is safe to take and will not cause long-term illness. Planners and health researchers are getting concerned that it is already getting late to start.
“It’s really important, at this juncture when vaccines are about to be distributed, to talk to people about the predictable side effects from the vaccine,” says Eric Toner, a physician and senior scholar with the Johns Hopkins Center for Health Security. “The worst case scenario would be that we don’t tell people this, and they have a reaction, and they either believe that they got Covid from the shot or that there’s something wrong.”
That is a pressing concern, for two reasons. First, fear of side effects turns out to be one of the main reasons why people doubt these vaccines. And second, mistrust opens the door not just to confusion but to weaponized disinformation, and those will prevent people taking a vaccine that they need.
The Henry J. Kaiser Family Foundation’s KFF Covid-19 Vaccine Monitor, a rolling survey of 1,600 people 18 and older that launched this week to provide an ongoing measure of public feeling, reveals that, overall, people are feeling more positive about the shot than they were earlier this year. In November, 71 percent of participants said they are likely to take the vaccine, up from 63 percent in a survey done in September. But the remaining 27 percent said they would probably or definitely never take it, a proportion that rose to 33 percent among Black adults, 33 percent among essential workers, and 29 percent among people working in health care. For those who are hesitant, the leading worry was fear of side effects.
This is a tricky thing to create reassurance about, because the side effects are real. Though the Pfizer vaccine was only granted emergency authorization last weekend, and the Moderna one is not authorized yet, tens of thousands of people received them earlier this year in clinical trials. In news accounts and on social media, participants have described experiencing “a severe hangover,” “fever … fatigue and chills,” “full-on Covid-like symptoms.” One participant told CNBC he shook so hard with chills that he cracked a tooth.
Those accounts match the data submitted by the companies to the FDA’s Vaccines and Related Biological Products Advisory Committee, which reviews safety and efficacy. According to briefing documents, the Pfizer formula caused fatigue in 59.4 percent of trial participants after their second dose, headaches in 51.7 percent, muscle pain in 37.3 percent, joint pain in 21.9 percent, chills in 35.1 percent, and headaches in 15.8 percent. The numbers for the Moderna formula, which were released Tuesday, are similar: fatigue in 68.5 percent of recipients, headache in 63 percent, aches and pains in 59.6 percent, chills in 43.4 percent, and fever in 15.6 percent.