The CDC and FDA cited six cases of blood clotting out of nearly 7 million doses. All of the cases involved women, one of whom died.
NEW YORK CITY
In the city, officials were working to reschedule 4,000 appointments for people who were set to get the vaccine.
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The J&J vaccine will be replaced by the Pfizer and Moderna versions, both of which require people to get two doses.
That also caused disruption to the homebound senior vaccination program in New York City which had been using the J&J vaccine, due to the fact that it did not require refrigeration.
The program is suspended until at least Sunday, Dr. David Chokshi said. The city is working to arrange transportation for homebound people so they can receive the Pfizer or Moderna vaccines instead.
Many people Eyewitness News spoke with said they are willing to take two trips to make sure the shot they're getting is safe.
This comes after all Johnson and Johnson doses were paused Tuesday in all 50 states.
"I received the shot, our health commissioner received the shot," New York City Mayor Bill de Blasio said Tuesday. "We believe in the effectiveness of the vaccine, but obviously we take seriously any warning and it needs to be fully investigated."
"Our vaccine command center is now coordinating new appointments for everyone scheduled for today and the coming days for Johnson and Johnson," the mayor continued. "Everyone who was scheduled will get a new appointment, obviously with Pfizer or Moderna."
In New Jersey, 244,000 doses of the Johnson & Johnson vaccine were administered prior to hitting pause. Gov. Phil Murphy confirmed Wednesday no similar adverse effects have been reported.
"Even with this pause, our overall goal of vaccinating 4.7 million adult New Jerseyans by the end of June remains in place and entirely achievable," Murphy said. "As of today, doses of J&J have accounted for only 4% of the more than 5.6 million total vaccine doses administered in New Jersey."
The governor reassured residents not to "panic or worry" as the review by the CDC and FDA is "coming out of an abundance of caution."
Murphy added the pause has no effect on Monday's opening of vaccine eligibility to all New Jerseyans ages 16 and over.
"We will keep pushing forward with the tools available to us," he said. "This review is critical to our efforts to ensure confidence in our vaccination program and the vaccines themselves."
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Clinical trials of the vaccine have also been put on hold.
As of Tuesday, officials say more than 6.8 million doses of the J&J vaccine have been administered in the U.S.
The pause is being characterized as a precaution, as officials work to reassure the public. It is is only expected to last days and not weeks as authorities work to ensure the vaccine is safe.
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