“My opinion is that the weight of the evidence suggests that we would probably save more lives by delaying second doses than by insisting on the schedule that was tested in the tests,” he said.
However, not all experts agree that changing dosing schedules is a good idea.
“Secondly, we really don’t know if delaying the second dose too long will give you the same degree of protection,” he said. In other words, there is not much research, since Covid-19 vaccines have been developed recently.
Meanwhile, as debates over postponing the second dose continue in the United States, so does the slow release of the vaccine, more deaths from Covid-19 and the spread of newly identified coronavirus variants that appear to be more transmissible. .
Getting a second dose is the priority, but ‘there is some room for maneuver’
It is still recommended that people take their second dose of the Covid-19 vaccine on time, said Dr. Rochelle Walensky, director of the Centers for Disease Control and Prevention in the United States, during a virtual meeting at the White House on Monday.
“Until we have more data,” said Walensky, people should continue to follow the test data, continuing the scheme of receiving two doses 21 days apart for the Pfizer / BioNTech vaccine and 28 days for the Modern vaccine. These are the two vaccines currently authorized for emergency use in the United States.
“The policy is that we certainly want everyone who receives the first dose to receive the second,” said Dr. Anthony Fauci, chief medical consultant to President Biden and director of the National Institute of Allergy and Infectious Diseases, during the Monday briefing. market.
But also on Monday, during a meeting of the International AIDS Society, Fauci said that if you are only a few weeks late, there is no reason to worry. “There is some leeway,” he said. “It’s not the end of the world if you are a little late. If you want to be six months late, it’s different.”
Delaying second doses would go against vaccine schedules that have been authorized by the U.S. Food and Drug Administration.
CNN confirmed with the FDA in January that if a manufacturer requests a change in its emergency use authorization, the manufacturer will need to send data to the FDA to support the requested change.
Some experts argue that there is evidence to support a possible change.
‘We need to have a really comprehensive review and discussion of this’
Lipsitch, from Harvard University, is in favor of spreading the vaccine doses over a larger population, rather than doubling the doses to half that population. “If you can get at least half the benefit, then it is better to distribute it,” he said.
For the Pfizer / BioNTech vaccine, called BNT162b2, the data suggest that the vaccine is 52% effective after just one dose and provides 95% protection against Covid-19 after two doses.
But trials have not been conducted to test single doses of mRNA vaccines.
“At this point, everything we know about vaccines suggests that in fact protection can be increased by boosting several months after the first dose,” said Osterholm, who was a coronavirus advisor to the Biden transition team.
The researchers hypothesized: “suppose that 1 million people are vaccinated, but only 1 million doses are available. If two doses are administered to each vaccinee and the effectiveness is 95%, 475,000 people will be protected. If single doses are administered and the effectiveness is 80%, 800,000 people will be protected. ”
“We need to have a really comprehensive review and discussion of this as soon as possible because you know that this new variant B.1.1.7 can cause an increase in our cases within weeks,” said Osterholm. He described the emergence of these variants as resembling a hurricane approaching the horizon.
“I feel like I’m sitting here on a beautiful beach – the light breeze, the perfectly blue sky and everyone – and I’m telling them to start evacuating. People are saying, ‘Are you crazy?’ But I see that 450 miles to the south, there is a category five hurricane, “said Osterholm.” That is the challenge. How do you get people to act? ”
Other experts, however, argue that having a longer period of time between doses of the vaccine may carry the risk of becoming more vulnerable to the new coronavirus and its variants.
Overall, Fauci said on Monday that being vaccinated against Covid-19 may help prevent more coronavirus variants in the future.
“You need to be vaccinated when it is available as quickly and expeditiously as possible,” said Fauci during the briefing at the White House on Monday, adding that viruses cannot mutate unless they replicate.
White House concerned about suppliers withholding doses
The Biden government expressed concern on Monday that health care providers could be basically accumulating doses of the Covid-19 vaccine for the second injections that could be administered in the first injections.
CDC data shows that about 26 million people have received at least one dose so far – but among them, almost 6 million have received their two doses.
“On January 20, states managed 46% of their stocks. Today, that number is 62%. We are focused on that every hour of every day,” said Slavitt on Monday.
Slavitt suggested that in some cases, patients’ appointments for the first dose are being canceled and urged the urgency to deliver the first doses as soon as possible. He said the government’s decision last week to provide a three-week window for vaccine delivery plans was intended to allay concerns that second doses might be withheld.
CNN’s Jen Christensen, Amanda Sealy, Michael Nedelman and Betsy Klein contributed to this report.