Serious COVID Vaccine Side Effects Still Rare As 65 Million Shots Given: 'Fantastic'

Tens of millions of people have been given COVID vaccines in the U.S., and data shows the shots continue to be safe.

The benefits of being vaccinated against COVID outweigh any risk of serious side-effects, scientists have told Newsweek, as the number of people safely inoculated continues to rise with few reports of serious adverse effects such as severe allergic reactions.

As of Tuesday, over 65 million people across the U.S. had been given a Pfizer or Moderna COVID vaccine.

Potential side effects are among the reasons some members of the public have been hesitant about getting vaccinated. One Associated Press-NORC Center for Public Affairs Research poll released this month found roughly a third of the 1,055 Americans surveyed would either definitely not or probably not get a vaccine, and 65 percent of those who did not want to get vaccinated cited side effects.

Common side-effects of the COVID vaccines available in the U.S. include pain and swelling on the injection arm, and fever, chills, tiredness and headache. They are "signs that your body is building protection," according to the CDC, and should go away in a few days.

However, it was feared more serious side effects could possibly emerge as the vaccines were administered to large populations.

Bell's palsy was one condition that it was feared could be linked to COVID vaccines. In one Pfizer/BioNTech vaccine study released to the FDA in December that involved 38,000 people, four participants developed Bell's palsy—a condition that causes temporary weakness or paralysis in facial muscles—between three to 48 weeks after vaccination.

But the Food and Drug Administration (FDA) later said this number was at the level expected in the general population, regardless of whether they had received the vaccine or not. It said there was "no clear basis upon which to conclude a causal relationship" between the vaccine and the condition, though it recommended surveillance going forward.

Additionally, federal health officials from the U.S. Centers for Disease Control and Prevention (CDC) reported in this month there had been 62 cases of anaphylaxis—an allergic reaction—after COVID vaccination out of 13,794,904 million first Pfizer and Moderna vaccine doses given between December 14, 2020 and January 13, 2021.

This averaged out at around 4.5 cases per million doses given, which the CDC described as "rare."

As the vaccine rollout continues and data continues to be compiled, experts have expressed optimism about the vaccines' continued safety.

Paul Offit, a medical doctor at the Children's Hospital of Philadelphia and member of the FDA's vaccine committee, told Newsweek: "Other than anaphylaxis, no serious side effects have been clearly caused by vaccines to prevent COVID."

'Millions to one'

Edward Hutchinson, a scientist at the Centre for Virus Research at the University of Glasgow in the U.K., told Newsweek: "While the immune response that the vaccines aim to create can make you a bit uncomfortable or feverish, particularly after the second dose, there's no sign that having the vaccines increases your chances of becoming seriously ill.

"Given the number of doses that have been given, the chances that we've missed that sort of effect are now literally millions to one against. This is absolutely fantastic news."

This point was echoed by Al Edwards, an associate professor at the University of Reading's pharmacy department.

He told Newsweek "the likelihood of serious side effects has shrunk" as more and more people have received a COVID vaccine.

Edwards said: "Because so many people are being vaccinated, all sorts of illnesses will appear in people who have been vaccinated—this is normal. Careful analysis is possible to check that the illness is not linked to the vaccine, and this analysis will continue for years.

"I think it was always expected that vaccines would be safe and effective. The big achievement is therefore getting here so quickly, with so few false starts.

"The vaccine is now known to be safe and taking it is far less risky than so many everyday activities."

Still, the safety of vaccines is continually monitored by pharmacists, doctors and other health workers who record side-effects in databases.

Dr. William Moss, executive director at the International Vaccine Access Center at Johns Hopkins Bloomberg School of Public Health, told Newsweek careful monitoring would be ongoing "particularly as vaccines are used in pregnant women and children."

Lisa Lee, a public health expert at Virginia Tech, previously told Newsweek scientists have "a vested interest" in ensuring vaccines are safe, and said long-term monitoring and corroboration of adverse effects is one way in which they do this.

Hutchinson said emerging data from Israel and the U.K. has shown vaccination has had "a clear impact" on the rate at which people get sick.

Person receiving a COVID vaccine
A medical worker is given a COVID vaccine at the Hartford Convention Center in Hartford, Connecticut on January 4, 2021. An expert has said the chances of scientists missing any adverse effects is going down as millions more are vaccinated. Joseph Prezioso/AFP/Getty

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