A pause in administration of the Johnson & Johnson COVID-19 vaccine is dealing a blow to U.S. vaccination efforts that have largely been speeding along.
The announcement from federal health officials on Tuesday morning, prompted by extremely rare cases of blood clots in people receiving the vaccine, was an unexpected setback for the U.S. vaccine rollout.
J&J is only a small part of the U.S. supply, so the White House offered reassurances that there are still more than enough doses from Pfizer and Moderna to keep up or even exceed the current 3 million shot-per-day pace.
But there is also the broader question of whether the news will lower public confidence in the vaccines, given that vaccine hesitancy was already a problem in some quarters. That concern left some health researchers questioning the wisdom of the pause.
“I don’t think it was the right decision,” Amesh Adalja, a senior scholar at the Johns Hopkins Center for Health Security, said of the pause, saying the move will fuel hesitancy and it will be hard to convince people to take the J&J shot again after it was paused.
“We’re in the midst of a pandemic that’s killing people every day,” he said. “We’re talking about less than 1 in a million cases … good luck restarting this now after what they’ve done.”
However, the bulk of experts backed halting doses, saying the pause could potentially reassure the public by showing how seriously officials take even a rare safety issue.
Health officials stressed that there have been no reports of serious side effects with the Pfizer or Moderna vaccines, and even with J&J, there are only six cases of blood clots reported so far out of about seven million shots given in the U.S.
“I know lots of folks think this will cause more vaccine hesitancy — and more harm than good,” tweeted Ashish Jha, dean of the Brown School of Public Health. “I’m honestly not so sure. My sense is confidence comes from people believing that we have a vigorous system that takes adverse events seriously. We do. This is how it works.”
Janet Woodcock, the acting Food and Drug Administration commissioner, said the pause could only be for a “matter of days.” A Centers for Disease Control and Prevention (CDC) panel of experts will meet on Wednesday to review the data.
Health officials also said a major reason for the pause was to give time to alert doctors that the usual drug to treat blood clots, called heparin, could actually cause harm for people who received the vaccine, and an alternative treatment should be used.
Asked if health officials overreacted given the rarity of the blood clots, Anne Schuchat, a top CDC official, acknowledged a balancing act but said the public and health providers needed time to be alerted.
“When we saw this pattern and were aware that treatment needed to be individualized for this condition, it was of the utmost importance for us to get the word out,” Schuchat said. “That said, the pandemic is quite severe, and cases are increasing in a lot of places and vaccination is critical, so we want to make sure that we make some recommendations quickly.”
While J&J is only a small part of the U.S. vaccination campaign, making up less than 5 percent of the doses administered so far, the pause also does cut away at the number of doses available.
There have been roughly 7 million J&J doses administered so far, and about 17 million distributed, according to CDC data, meaning that about 10 million doses that could be shortly going into arms will not be.
The J&J vaccine also only required one shot, not two, and was easier to store, meaning that it was being used in some harder-to-reach parts of the country.
While the company had been plagued with manufacturing problems, J&J had promised 100 million doses by the end of May. It is now in question whether those doses will be usable, given the pause.
President Biden previously said there will be enough vaccine doses for all American adults by the end of May. Asked if that was still true, White House COVID-19 response coordinator Jeff Zients said Tuesday there will be enough doses between Pfizer and Moderna “for all Americans who want to get vaccinated by May 31,” a slightly different phrasing than saying there will be enough doses for all adults, period.
Pfizer did announce Tuesday that it can deliver 10 percent more doses by the end of May, which could help fill the gap.
Even before the J&J news, a Kaiser Family Foundation poll released at the end of March found that 29 percent of Republicans said they would “definitely not” get the vaccine, compared with 13 percent of people overall.
Europe has had troubles with similar reports of rare blood clots in a different vaccine, from AstraZeneca, which is approved there but not yet in the U.S. The problems with J&J and AstraZeneca vaccines could be related, because both use harmless viruses called adenoviruses as the mechanism to deliver the vaccine’s protection, which makes them different than the Pfizer and Moderna vaccines, which use mRNA.
A YouGov poll last month found confidence in the AstraZeneca vaccine took a dive in Europe after countries there paused its use because of blood clot concerns. In Italy and Spain, the share of the public saying the AstraZeneca vaccine was safe fell from 54 and 59 percent, respectively, to 36 and 38 percent.
Zeke Emanuel, a prominent health expert who was a member of Biden’s COVID-19 advisory board during the transition, raised concerns about the consequences of the pause on the J&J vaccine.
“I’m very concerned this could unnecessarily undermine confidence in the vaccine,” he tweeted. “We still need to see the data, but this rushed decision suggests officials believe they don’t need the J&J vaccine to actually reach herd immunity, even though it’s a better option for many.”
He said the risks from the vaccine needed to be compared to the much greater risks of actually getting COVID-19, as the pandemic continues to rage.
The pause could soon be lifted, and some experts said going through the process shows the system of monitoring for vaccine safety concerns is working.
“This shows that regulatory entities are doing their job,” tweeted Leana Wen, visiting professor at George Washington University School of Public Health. “Even something very rare (6 cases out of 7 million) will be immediately looked into.”
Jesse Goodman, a former FDA chief scientist now at Georgetown University, said it was a “difficult decision” but a “straightforward” one given the need to review the data.
“I think it’s reasonable to take a pause,” he said, while acknowledging that “communicating around it is very challenging.”