WASHINGTON  (NewsNation Now) — U.S. health officials lifted an 11-day pause on COVID-19 vaccinations using Johnson & Johnson’s single-dose shot on Friday, after scientific advisers decided its benefits outweigh a rare risk of blood clot.

The government uncovered 15 vaccine recipients who developed a highly unusual kind of blood clot, out of nearly 8 million people given the J&J shot. All were women, most under age 50. Three died, and seven remain hospitalized.

But ultimately Friday, the Food and Drug Administration and Centers for Disease Control and Prevention decided that J&J’s one-and-done vaccine is critical to fight the pandemic — and that the small clot risk could be handled with warnings to help younger women decide if they should use that shot or an alternative.

The Centers for Disease Control and Prevention said the J&J vaccine has important advantages for some people who were anxiously awaiting its return. And the Food and Drug Administration updated online vaccine information leaflets for would-be recipients and health workers so that shots could resume as early as Saturday.

New York, Virginia, Vermont, Missouri and Michigan were among the states ordering or recommending a resumption.

“Above all else, health and safety are at the forefront of our decisions,” CDC Director Dr. Rochelle Walensky said in a statement. “Our vaccine safety systems are working. We identified exceptionally rare events – out of millions of doses” of the J&J shot and will continue to monitor them.

The U.S. decision — similar to how European regulators are rolling out J&J’s shot — comes after CDC advisers earlier Friday voted 10-4 to resume vaccinations but panelists made clear that they must come with warnings about the risk. The group debated but ultimately steered clear of outright age restrictions.

“This is an age group that is most at risk (of the clotting) that is getting vaccine predominately to save other peoples’ lives and morbidity, not their own. And I think we have a responsibility to be certain that they know this,” said Dr. Sarah Long of Drexel University College of Medicine, who voted against the proposal because she felt it did not go far enough in warning women.

The committee members all agreed the J&J vaccine “should be put back into circulation,” panel chairman Dr. Jose Romero, Arkansas’ health secretary, said in an interview after the vote. “The difference was how you convey the risk … It does not absolve us from making sure that people who receive this vaccine, if they are in the risk group, that we inform them of that.”

European regulators earlier this week made a similar decision, deciding the clot risk was small enough to allow the rollout of J&J’s shot. But how Americans ultimately handle J&J’s vaccine will influence other countries that don’t have as much access to other vaccination options.

Dr. Paul Stoffels, J&J’s chief scientific officer, pledged that the company would work with U.S. and global authorities “to ensure this very rare event can be identified early and treated effectively.” J&J already was working with the FDA on a warning label for the shot.

At issue is a weird kind of blood clot that forms in unusual places, such as veins that drain blood from the brain, and in patients with abnormally low levels of the platelets that form clots. Symptoms of the unusual clots, dubbed “thrombosis with thrombocytopenia syndrome,” include severe headaches a week or two after the J&J vaccination — not right away — as well as abdominal pain, nausea.

The government initially spotted six cases of the rare clots, with nine more cases coming to light in the last week or so. But even the first needle-in-a-haystack reports raised alarm because European regulators already had uncovered similar rare clots among recipients of another COVID-19 vaccine, from AstraZeneca. The AstraZeneca and J&J shots, while not identical, are made with the same technology.

European scientists found clues that an abnormal platelet-harming immune response to AstraZeneca’s vaccine might be to blame — and if so, then doctors should avoid the most common clot treatment, a blood thinner called heparin.

That added to U.S. authorities’ urgency in pausing J&J vaccinations so they could tell doctors how to diagnose and treat these rare clots. Six patients were treated with heparin before anyone realized that might harm instead of help.

Dr. Jesse Goodman of Georgetown University closely watched Friday’s deliberations and said people should be made aware of the clotting risk but that it shouldn’t overshadow the benefits of COVID-19 protection.

“We need to treat people as adults, tell them what the information is and give them these choices,” said Goodman, a former vaccine specialist at the FDA.

Two-dose vaccines from Pfizer and Moderna, which are made differently and haven’t been linked to clot risks, are the mainstay of the U.S. vaccination effort. But many states had been counting on the easier-to-store, one-and-done option to also help protect hard-to-reach populations including people who are homeless or disabled.

The CDC’s advisers struggled to put the rare clot cases into perspective. COVID-19 itself can cause a different type of blood clots. So can everyday medications, such as birth control pills.

The side effect debate isn’t the only hurdle facing J&J. The FDA separately uncovered manufacturing violations at a Baltimore factory the company had hired to help brew the vaccine. No shots made by Emergent BioSciences have been used — J&J’s production so far has come from Europe. But it’s unclear how the idled factory will impact J&J’s pledge to provide 100 million U.S. vaccine doses by the end of May and 1 billion doses globally this year.

J&J has faced several setbacks since its shot gained emergency authorization use in February, first drawing scrutiny over its halting process to scale up production of the vaccine, and then over rare cases of clots in a handful of vaccine recipients. Earlier this week, FDA inspectors blasted the cleanliness and medical safety of an Emergent BioSolutions plant making the J&J vaccine in a report released Wednesday.

Updated Emergency Use Authorization

Updated Fact Sheet for Patients

Updated Fact Sheets for Healthcare Providers

Statements

“Safety is our top priority. This pause was an example of our extensive safety monitoring working as they were designed to work—identifying even these small number of cases. We’ve lifted the pause based on the FDA and CDC’s review of all available data and in consultation with medical experts and based on recommendations from the CDC’s Advisory Committee on Immunization Practices. We have concluded that the known and potential benefits of the Janssen COVID-19 Vaccine outweigh its known and potential risks in individuals 18 years of age and older. We are confident that this vaccine continues to meet our standards for safety, effectiveness and quality. We recommend people with questions about which vaccine is right for them have those discussions with their health care provider.”

Janet Woodcock, M.D., Acting FDA Commissioner

“Above all else, health and safety are at the forefront of our decisions. Our vaccine safety systems are working. We identified exceptionally rare events – out of millions of doses of the Janssen COVID-19 administered – and we paused to examine them more carefully. As we always do, we will continue to watch all signals closely as more Americans are vaccinated. I continue to be encouraged by the growing body of real-world evidence that the authorized COVID-19 vaccines are safe and effective, and they protect people from disease, hospitalization, and death. I urge anyone with questions about the COVID-19 vaccines to speak with their healthcare provider or local public health department.”

DR. ROCHELLE P. WALENSKY, CDC Director

“The AMA commends the Advisory Committee on Immunization Practices (ACIP) for today reaffirming its recommendation on the use of the Janssen COVID-19 vaccine for persons 18 years of age and older in the U.S. population under the Food and Drug Association’s (FDA) Emergency Use Authorization. The population-level data presented during ACIP’s meeting today clearly demonstrates that the benefits of this approach outweigh the risks, which include becoming infected with COVID-19 and the potential for severe illness or death.

The AMA will continue to work with the FDA and the Centers for Disease Control and Prevention (CDC) to ensure physicians and patients are aware of the rare, but increased risk of thrombosis with thrombocytopenia syndrome (TTS) in women under the age of 50, as well as the appropriate treatment, so they can act quickly. The pause on the Janssen COVID-19 vaccine has demonstrated the strength of our nation’s vaccine safety monitoring system and the transparent and careful deliberations by the ACIP should raise confidence in FDA-authorized and CDC-recommended COVID-19 vaccines. The AMA continues to encourage everyone who is eligible for COVID-19 vaccines to get vaccinated as soon as possible. Even after being vaccinated, we urge everyone to continue wearing masks, maintaining physical distancing and washing hands to prevent the spread of COVID-19 to those who haven’t yet been vaccinated.”

Dr. Susan R. Bailey, President, American Medical Association

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The Associated Press and Reuters contributed to this report.