A head-to-head study of all three authorized coronavirus vaccines in the United States finds the Moderna vaccine is slightly more effective than Pfizer's in real-life use in keeping people out of the hospital, and Johnson & Johnson's Janssen vaccine comes in third, but still provides 71% protection.

Pfizer's vaccine provided 88% protection against hospitalization, and Moderna's was 93% effective. The U.S. Centers for Disease Control and Prevention led a nationwide study of vaccination involving more than 3,600 adults hospitalized for COVID-19 between March and August.

"Among U.S. adults without immunocompromising conditions, vaccine effectiveness against COVID-19 hospitalization during March 11- August 15, 2021, was higher for the Moderna vaccine (93%) than the Pfizer-BioNTech vaccine (88%) and the Janssen vaccine (71%)," the team wrote in the CDC's weekly report on death and disease, the MMWR.

"Although these real-world data suggest some variation in levels of protection by vaccine, all FDA-approved or authorized COVID-19 vaccines provide substantial protection against COVID-19 hospitalization."

They found that the biggest difference between the vaccine made by Moderna and Pfizer/BioNtech's vaccine was driven by a decline that started about four months after people were fully vaccinated with Pfizer's vaccine.

"Differences in vaccine effectiveness between the Moderna and Pfizer-BioNTech vaccine might be due to higher mRNA content in the Moderna vaccine, differences in timing between doses (three weeks for Pfizer-BioNTech versus four weeks for Moderna), or possible differences between groups that received each vaccine that were not accounted for in the analysis," the team wrote.

"Vaccine effectiveness for the Pfizer-BioNTech vaccine was 91% at 14 -120 days after receipt of the second vaccine dose but declined significantly to 77% at more than 120 days," the team wrote.

Pfizer's and Moderna's vaccines both use genetic material called messenger RNA to deliver immunity, but they use differing doses and slightly different formulations. The Janssen vaccine uses an inactivated common cold virus called adenovirus — a viral vector — to carry genetic instructions into the body.

"A single dose of the Janssen viral vector vaccine had comparatively lower anti-SARS-CoV-2 antibody response and vaccine effectiveness against COVID-19 hospitalizations," the team said. "Understanding differences in vaccine effectiveness by vaccine product can guide individual choices and policy recommendations regarding vaccine boosters. All FDA-approved or authorized COVID-19 vaccines provide substantial protection against COVID-19 hospitalization."CDC worked with researchers across the country to study 3,689 patients at 21 hospitals in 18 states for the study. They also looked at antibodies in the blood of 100 healthy volunteers after they had been vaccinated with one of the three available vaccines.

"These real-world data suggest that the two-dose Moderna and Pfizer-BioNTech mRNA vaccine regimens provide more protection than does the one-dose Janssen viral vector vaccine regimen. Although the Janssen vaccine had lower observed vaccine effectiveness, one dose of Janssen vaccine still reduced risk for COVID-19-associated hospitalization by 71%," they wrote.

The study had limitations. "This analysis did not consider children, immunocompromised adults, or vaccine effectiveness against COVID-19 that did not result in hospitalization," the team wrote. Plus, the volunteers were only followed for 29 weeks — just over six months.

The U.S. Food and Drug Administration authorized Johnson & Johnson's COVID-19 vaccine Saturday. It is the first single dose COVID-19 vaccine available in the U.S. and is one that "checks nearly all the boxes."

With more than 28.5 million confirmed COVID-19 cases and over 511,000 reported deaths in the U.S. since the start of the pandemic, and while the demand for vaccine still far exceeds supply, these vaccines can't come soon enough.

"A third safe and effective vaccine is very welcome news," Andy Slavitt, the White House's senior for COVID Response, tweeted on Friday.

The vaccine, made by Janssen, J&J's vaccine arm, is safe and effective, and it's considered flexible. It's a single dose, and it doesn't require special storage.

The vaccine is authorized for people ages 18 and older.

"We need a vaccine that can be quickly mass produced," Dr. Greg Poland, head of the Mayo Clinic's Vaccine Research Group, said Friday. "We'd want to see a reasonable duration of efficacy and protection.

"The Janssen vaccine candidate checks nearly all the boxes."

The vaccine was tested in more than 44,000 people in the U.S., South Africa and Latin America. Globally, it was 66.1% effective against moderate to severe/critical COVID-19 at least four weeks after vaccination, according to an FDA analysis. In the U.S., it is considered 72% effective, and offered 86% protection against severe forms of the disease.

"One dose will keep you out of the hospital, keep you out of the intensive care unit, and keep you out of the morgue," Dr. Paul Offit, a vaccine adviser to the FDA, told CNN's Wolf Blitzer on Friday.

The vaccine comes with few side effects, most of which are mild, including pain at the injection site, headache, fatigue and muscle pain.

Overall, non-fatal serious adverse events were infrequent, according to the FDA's analysis, and there were no reported cases of anaphylaxis following vaccination in the trial. There have been a small number of severe allergic reactions with the Moderna and Pfizer/BioNTech vaccines. For example, in the first week of the Pfizer vaccine rollout, there were only 29 cases out of 1.9 million doses administered, according to the U.S. Centers for Disease Control and Prevention.

More research is needed, but the FDA analysis also hinted that the J&J vaccine may help prevent asymptomatic infections.

A January study from the CDC showed that most coronavirus cases are spread by people without symptoms. If a vaccine prevented asymptomatic infection, it might help reduce opportunities to transmit the disease — not just keep the vaccinated from getting sick.

With so much positive data, an independent group of advisers voted unanimously on Friday to recommend the emergency use authorization of the J&J vaccine.

"I think it's a relatively easy call. It clearly gets way over the bar, and it's nice to have a single-dose vaccine," Dr. Eric Rubin, a member of the committee who is also the editor in chief of The New England Journal of Medicine and a professor at the Harvard T.H. Chan School of Public Health, said after the vote.

There is some concern that because the public has heard that the shot is only 72% protective in the U.S., and the Pfizer and Moderna COVID-19 vaccines are about 95% protective, some will think this is a "second class" vaccine, but the experts say those numbers are highly misleading.

"It's difficult to make an apples-to-apples comparison between vaccines authorized based on data collected before new variants are believed to have been in widespread circulation," said Sarah Christopher, the policy advocacy director at the National Women's Health Network. Christopher spoke during the public comment section of the FDA's advisory meeting on Friday.

The Pfizer and Moderna COVID-19 vaccines were tested earlier in the pandemic when there were fewer known variants. FDA research found that the majority of the cases that happened during the South African part of the J&J trial came from a newer and possibly more contagious variant.

Public health experts say people should take whatever shot is first available to them.

"If I had a J&J vaccine available today and a Moderna vaccine available tomorrow, I would be happy to take the J&J today. I don't feel like I would need to wait. They are all terrific vaccines for the things that we care about," Dr. Ashish Jha, dean of the Brown University School of Public Health, told a House Ways and Means Health Subcommittee hearing Friday.

Experts have said variants may fuel a surge of cases in the spring in the U.S., and say that's one reason why it's important to get as many people vaccinated as quickly as possible.

"We'll be seeing how much of an impact the variants have and how best these vaccines can address them, whether it will be booster doses, or other vaccines," said Dr. Aditya Gaur, a co-lead investigator on the J&J trial at St. Jude in Memphis. "But I think one could not have asked for better from this first round of vaccine development from a standpoint of how quickly it has happened and how quickly it has started to roll out around the world."

On Sunday, the CDC's Advisory Committee on Immunization Practices, known as ACIP, will meet to set the guidelines for who should get the vaccine. Their vote is scheduled for 3 p.m. ET.

From there, the much needed vaccine could start rolling out to vaccine centers around the country.

While the initial supply is limited — the company says it only has about 4 million doses of its vaccine ready to ship "immediately" — it should have 20 million ready by the end of March.

The advancement of the Johnson & Johnson coronavirus vaccine is "really good news for the world," Dr. Francis Collins, director of the National Institutes of Health, told CNN's Wolf Blitzer on Friday. Even with cases in the U.S. declining recently, the pandemic is far from over. "The best way to get done is with this vaccine being added to the others."

COVINGTON, Ky. — A third COVID-19 vaccine option could soon be on the way – a panel unanimously recommended the emergency use authorization for the Johnson & Johnson vaccine Friday afternoon, and FDA approval could be granted shortly.

The world’s largest trial for the Johnson & Johnson vaccine was headed up in Covington.

Tim Schroeder, the CEO of CTI Clinical Trial & Consulting Services, has been part of more than 100 drug approvals in his career.

“I have to say, this particular one will always have a special place," he said. "Just because of the circumstances the research was done under and the positive impact that this will ultimately have for society.”

He said the region has played an integral role in all three vaccines developed so far.

“Cincinnati Children’s led the Pfizer effort. UC led the Moderna effort. We were fortunate to lead the J & J effort,” Schroeder said. “In some ways, that’s really unique, especially for a region and population of a couple million.”

Globally, the company recruited 43,000 people to take part in the study, 500 of them in the Tri-State. Half received the vaccine, half received a placebo. Participants are monitored for a full two years. Schroeder said the study had the highest number of minority groups participating.

So far, side effects include minor body aches, headaches or fever.

“Typically when we have a new vaccine like influenza each year, we study in thousands of patients,” Schroeder said. “In the case of this, we’re studying in tens of thousands of patients.”

Local governments believe the more vaccine available, the easier it will be to get it in the hands of those who need it.

“Based on our current plans, we’ll have a lot more independent pharmacies out there that are ready, able and willing to step up to the plate and help communities,” Kentucky Gov. Andy Beshear said.

Ohio health officials said the panel’s approval of the vaccine comes as a welcome sign.

“It’s clear that it’s 100% effective even in South Africa and Brazil by preventing hospitalizations and death. Very encouraging,” said Ohio Department of Health medical officer Dr. Bruce Vanderhoff. “Is one better than the other? At this point in time, where we are in the pandemic, any one that’s offered to you is one you should take.”

Once the FDA gives final approval, Johnson & Johnson could have as many as 4 million doses ready to be shipped next week, and as many as 10 million over the next month.

The packing and shipping of a third COVID-19 vaccine approved for use in the U.S. is underway. Johnson & Johnson’s single-dose shot will start going into Americans’ arms in a matter of days.

Nearly 4 million doses are going out just this week. That's all of the current supply.

The number of doses states are getting is proportional to population, like with the Pfizer and Moderna vaccines.

Johnson & Johnson’s CEO says he's confident the company will be able to deliver on its promise of 100 million doses by June, and up to 1 billion by the end of the year.

“Johnson &Johnson built its vaccine from a virus that causes the common cold, known as adenovirus,” said Dr. Leo Nissola, a COVID Act Now medical advisor.

The science behind Johnson & Johnson's single-dose COVID-19 vaccine and the Moderna and Pfizer two-shot vaccines is different, but not new.

Johnson & Johnson’s vaccine takes a small amount of genetic material from the coronavirus and combines it with a weakened version of a common cold virus called adenovirus. That combination doesn't make us sick.

Adenovirus technology was also used to make Ebola and tuberculosis vaccines.

Pfizer and moderna use mRNA technology, which uses a genetic code to make the antigen protein specific to COVID-19. This code tells our body to make the antigen itself, prompting an immune response.

“The messenger RNA platform allows for scientists and drug makers to update the coding on these vaccines sooner, faster and at a different pace than adenovirus vectored vaccine, so in that sense, should we need a boost, our immune shot very likely will come from those mRNA based platforms,” said Dr. Nissola.

Pfizer and Moderna are already testing a third, booster shot to protect against COVID-19 variants.

Meanwhile, Johnson & Johnson may have the advantage of one and done for now, since it only requires a single dose. It can be stored for months in a refrigerator.

All three were found to be highly effective in preventing severe disease and death.

“It makes me hopeful that by summer, we will be able to vaccinate millions and millions of people and have a little bit more normalcy back,” said Dr. Nissola.

The J&J vaccine is also expected to boost vaccination equity since it's only one dose and is easier to store.

SAN DIEGO — A new study released Tuesday suggests the COVID-19 vaccine made by Johnson & Johnson produces significantly weaker antibody defenses to the delta variant than the original strain.

However, medical experts say the results are far from proof that the one-dose vaccine is ineffective against the variant in the real world.

The study by a team at New York University prompted a flurry of concerned headlines Tuesday. The New York Times initially published a report titled, "One Dose of J.&J. Vaccine Is Ineffective Against Delta, Study Suggests."

The paper later changed the title to "J.&J. Vaccine May Be Less Effective Against Delta, Study Suggests."

The NYU scientists drew blood from 10 people who got the J&J vaccine and put their protective antibodies in a dish. Then, they introduced different COVID-19 variants to see how well the antibodies stopped them.

On average, the team found the Johnson & Johnson vaccine was about seven times weaker against the delta variant than the original strain of COVID-19. Those results were a more significant drop-off than those seen in people who received the Pfizer or Moderna vaccine.

The NYU study has not yet undergone peer review.

J&J is the only one-dose COVID-19 vaccine approved for emergency use in the U.S. The authors of the paper suggested that people who got the shot may benefit from a second dose.

However, outside experts like UC San Francisco's Dr. Peter Chin-Hong said it's too soon to make that assumption.

"You can't necessarily extrapolate laboratory-based studies to what happens in real life," he said.

That's because vaccines create more defenses than just antibodies. They also train living cells called "Killer T cells" and "Helper T cells." The three branches work together like branches of the military — the army, the navy and the air force.

"What we've known about J&J for a while is that the protection doesn't directly track with those antibody numbers," said Dr. Shane Crotty, a professor at the La Jolla Institute of Immunology.

During the company's clinical trials in South Africa, the Johnson & Johnson vaccine was 64% effective against the elusive variant there, now called the beta variant.

While the new NYU study did not measure T cell responses, it found the J&J antibodies perform about the same against delta as they do against beta — an encouraging clue, Crotty said.

The Johnson & Johnson vaccine "may lose a little more of its protection against just cases per se, but it'll still stay really highly protective against bad COVID, hospitalization level COVID," he said.

The one-dose J&J vaccine was authorized later than Pfizer's and Moderna's vaccines, so there have been fewer studies on it.

The NYU study conflicts with some of the earlier data. Experts say that could be because the team ran tests less than three months after the shot, on average.

Johnson & Johnson released research this month that found antibody levels grew in strength over eight months.

"Just like wine, it may get better with age," Chin-Hong said.

For now, experts say the bigger worry is about those who are still unvaccinated — people who have not gotten the shot account for 99% of the hospitalizations and deaths from the delta variant.

This story was originally published by Derek Staahl on Scripps station KGTV in San Diego.

Related video above: The importance of sunscreen — regardless of skin type and forecast

Johnson & Johnson said Wednesday that it is recalling five of its sunscreen products after some samples were found to contain low levels of benzene, a chemical that can cause cancer with repeated exposure.

The affected products, packaged in aerosol cans, are Aveeno Protect + Refresh aerosol sunscreen, and four Neutrogena sunscreen versions: Beach Defense aerosol sunscreen, CoolDry Sport aerosol sunscreen, Invisible Daily Defense aerosol sunscreen and UltraSheer aerosol sunscreen.

The recall includes all can sizes and all levels of sun protection factor, or SPF. The products were distributed nationwide through retailers.

The health care giant said the benzene was found after testing by the company and an independent laboratory. It is investigating how the chemical got into the products.

J&J said it's working to get all lots of the five products removed from store shelves. It urged consumers to stop using the sunscreens immediately and said customers can get a refund by calling J&J's Consumer Care Center at 1-800-458-1673. More information is available at the websites for Neutrogena and Aveeno.

J&J said in a statement that "use of these products would not be expected to cause adverse health consequences" and that it voluntarily decided to recall them "out of an abundance of caution." The statement added that people should use an alternate sunscreen to protect themselves from the skin cancer melanoma.

Benzene is a highly flammable, widely used chemical that's present throughout the environment. It can cause cancer with repeated exposure at high enough levels. It also can damage the immune system and prevent cells from functioning properly, according to the U.S. Centers for Disease Control and Prevention.

The chemical's effects vary by whether a person accidentally inhales or ingests it or gets it on skin and clothing. Symptoms range from dizziness and irregular heartbeat to convulsions and, at very high levels, death.

J&J, which is based in New Brunswick, New Jersey, said it has notified the Food and Drug Administration of the recall.

The Johnson & Johnson coronavirus vaccine provides immunity that lasts at least eight months and appears to provide adequate protection against the worrying delta variant, the company said in a statement Thursday night.

"Current data for the eight months studied so far show that the single-shot Johnson & Johnson COVID-19 vaccine generates a strong neutralizing antibody response that does not wane; rather, we observe an improvement over time," Dr. Mathai Mammen, head of research and development at J&J's Janssen vaccine arm, said in a statement.

The company said one dose of the vaccine elicits a lasting antibody response and generates immune cells called T-cells that last eight months.

Dr. Dan Barouch of Beth Israel Deaconess Medical Center and Harvard Medical School and colleagues tested blood taken from 20 volunteers in an early stage, Phase 1/2 trial of the vaccine.

"These data are promising and reassuring," Barouch told CNN. Barouch has submitted his findings to the BioRxiv pre-print server.

"Data showed that T-cell responses — including CD8+ T-cells that seek out and destroy infected cells — persisted over the eight-month timeframe examined," the company said.

These are not real-world efficacy data, but antibody and T-cell response usually indicate protection, Barouch said.

Pfizer/BioNTech and Moderna have both said their two-dose vaccines are protective for at least six months and researchers at Washington University in St. Louis reported earlier this week that their studies of vaccinated volunteers indicate protection from the vaccines should last much longer than that — even for years. They did not test the J&J vaccine.

Barouch's team also tested blood from the vaccinated volunteers against the most worrying variants of the virus, including the delta variant first seen in India, the beta variant first seen in South Africa, and the gamma variant spreading in Brazil.

"We see robust neutralizing antibody coverage of the variant," Barouch said. Neutralizing antibodies are the immune system proteins that inactivate a virus before it can replicate.

"A single dose of the Johnson & Johnson COVID-19 vaccine generated neutralizing antibodies against a range of variants of concern, which increased over time, including against the increasingly prevalent and more transmissible delta variant, the partially neutralization-resistant beta, the gamma variants and others," the company said.

Separately, a Janssen team in the Netherlands studied blood taken from eight vaccinated volunteers in the company's Phase 3 trial and found similar results against the variants.

Earlier Thursday, J&J said a second or booster dose of its vaccine would not be necessary.

Dr. Anthony Fauci agreed. "With regard to the idea of boosting, there's a lot of talk about that — but right now I think we still need to remember that in fact, the J&J vaccine is a highly effective vaccine that has been recommended very clearly and has received an emergency use authorization," Fauci, who is director of the National Institute of Allergy and Infectious Diseases, told a White House briefing Thursday.

However, J&J, along with the U.S. National Institutes of Health, is testing to see whether giving people two doses of its vaccine will provide better protection.

The New York attorney general says Johnson & Johnson has agreed to pay $230 million to settle claims that the pharmaceutical giant helped fuel the opioid crisis.

The deal requires Johnson & Johnson to make a series of payments over nine years to cover the total.

Attorney General Letitia James said the drugmaker also agreed to end the manufacturing and distribution of opioids across New York and the rest of the nation.

Johnson & Johnson said the settlement is not an admission of wrongdoing.

It downplayed the attorney general’s announcement, saying the settlement involved two prescription painkillers already no longer sold in the U.S.

A batch of Johnson & Johnson’s COVID-19 vaccine failed quality standards and can’t be used, the drug giant said Wednesday.

The drugmaker didn’t say how many doses were lost, and it wasn’t clear how the problem would impact future deliveries.

A vaccine ingredient made by Emergent BioSolutions — one of about 10 companies that Johnson & Johnson is using to speed up manufacturing of its recently approved vaccine — did not meet quality standards, J&J said.

J&J said the Emergent BioSolutions factory involved had not yet been approved by the U.S. Food and Drug Administration to make part of the vaccine. Emergent declined to comment.

J&J had pledged to provide 20 million doses of its vaccine to the U.S. government by the end of March, and 80 million more doses by the end of May. Its statement on the manufacturing problem said it was still planning to deliver 100 million doses by the end of June and was “aiming to deliver those doses by the end of May.”

President Joe Biden has pledged to have enough vaccines for all U.S. adults by the end of May. The U.S. government has ordered enough two-dose shots from Pfizer and Moderna to vaccinate 200 million people to be delivered by late May, plus the 100 million shots from J&J.

A federal official said Wednesday evening the administration’s goal can be met without additional J&J doses.

A J&J spokesman said earlier Wednesday that the company met the end-of-March goal, but did not respond to questions about whether the Emergent plant in Baltimore, known as Bayview, had been cleared by FDA.

As of Wednesday, J&J had provided about 6.8 million doses to the U.S. vaccine effort, according to the Centers for Disease Control and Prevention’s online vaccine tracker. Some additional doses may not yet have been recorded as delivered, and federal health officials said Wednesday that another 11 million doses of the vaccine would be available for shipments starting on Thursday.

It was not immediately clear where those 11 million doses originated, but J&J has been shipping finished vaccines from its factory in the Netherlands to the U.S.

Emergent, a little known pharmaceutical company granted a major role in the federal government’s response to coronavirus pandemic, has been repeatedly cited by the FDA for problems ranging from poorly trained employees to cracked vials and mold around one of its facilities, according to records obtained by The Associated Press through the Freedom of Information Act.

The records cover inspections at Emergent facilities, including Bayview, since 2017. Following a December 2017 inspection at an Emergent plant in Canton, Massachusetts, the FDA said the company hadn’t corrected “continued low-level mold and yeast isolates” found in the facility. Nearly a year later, agency investigators questioned why Emergent had “an unwritten policy of not conducting routine compliance audits” at a separate plant in Baltimore, known as Camden, where an anthrax vaccine is filled into vials.

Emergent’s revenues skyrocketed during the Trump administration, jumping from around $523 million in 2015 to more than $1.5 billion in 2020. The company has invested heavily in lobbying the federal government, according to disclosure records, which show the company spent $3.6 million on lobbying in 2020 alone.

J&J said it was putting more of its manufacturing and quality experts inside Emergent’s factory to supervise production of the COVID-19 vaccine, a move meant to enable delivery of an additional 24 million vaccine doses through April.

J&J said it still expects to deliver more than 1 billion vaccine doses globally by the end of the year.

The J&J vaccine has been viewed as crucial for vaccination campaigns around the world, because only one shot is required and it can be shipped and stored at standard refrigeration temperatures, unlike some other vials that must be kept frozen. The company also has pledged to sell the vaccine without a profit, but only during the pandemic emergency.

The problem with the vaccine batch was first reported by The New York Times. The FDA said it was aware of the situation but declined further comment.

___

Johnson reported from Fairless Hills, Pennsylvania, and Lardner from Washington. AP reporters Matt Perrone and Zeke Miller in Washington contributed.

WASHINGTON — Johnson & Johnson says U.S. health officials have extended the expiration date for its COVID-19 vaccine by six weeks.

The drugmaker said Thursday that the Food and Drug Administration approved a shelf life of four-and-a-half months for the one-dose shots.

The decision comes just days after the Wall Street Journal reported that millions of doses of the vaccine were set to expire in the coming weeks. Following that report, White House COVID-19 response team adviser Andy Slavitt said that regulators were looking at opportunities for "continued storage."

State officials recently warned that millions of doses would reach their original three-month expiration date by the end of June. The stockpile of doses developed earlier this year when the use of the drug was briefly paused while officials assessed reports of blood clotting.

The CDC and FDA both said the benefits of the vaccine outweighed the risk following an 11-day pause. However, that stoppage has left some states with more supply than demand.

Earlier this week, Ohio Gov. Mike DeWine said that his state has 200,000 doses of the J&J vaccine that are set to expire on June 23.

“The time to act is now,” DeWine said. “For Ohioans who have been waiting to get their vaccine, I urge you to take action now. There are many opportunities throughout the state to get a vaccine. The Johnson & Johnson vaccine is one of those options. It is safe and effective and only requires one shot. In just two weeks, you could be protected from this virus. Getting vaccinated is the quickest way out of the pandemic and the fastest way for us to return to the lives we remember.”

Vaccine expiration dates are based on information from drugmakers on how long the shots stay at the right strength. Regulators are reviewing those dates as companies have continued to test batches.

The extension comes as the number of U.S. vaccinations continues to slip. While 64% of Americans are fully vaccinated, Bloomberg reports that the number of daily vaccinations the U.S. has conducted has steadily dropped since mid-April.

Johnson & Johnson's COVID-19 vaccine will remain in limbo a while longer after U.S. health advisers told the government Wednesday that they need more evidence to decide if a handful of unusual blood clots were linked to the shot — and if so, how big the potential risk really is.

The reports are exceedingly rare — six cases out of more than 7 million U.S. inoculations with the one-dose vaccine. But the government recommended a pause in J&J vaccinations this week, not long after European regulators declared that such clots are a rare but possible risk with the AstraZeneca vaccine, a shot made in a similar way but not yet approved for use in the U.S.

At an emergency meeting, advisers to the Centers for Disease Control and Prevention wrestled with the fact that the U.S. has enough vaccine alternatives to do without the J&J vaccine for a time, but other countries anxiously awaiting the one-and-done shot may not.

One committee member, Dr. Grace Lee, was among those who advocated tabling a vote. She echoed concerns about getting more data to better understand the size of the risk and whether it was greater for any particular group of people.

"I continue to feel like we're in a race against time and the variants, but we need to (move forward) in the safest possible way," said Lee, of Stanford University.

The clots under investigation are highly unusual. They occurred in strange places, in veins that drain blood from the brain, and in people with abnormally low levels of clot-forming platelets. The six cases raised an alarm bell because that number is at least three times more than experts would have expected to see even of more typical brain-drainage clots, said CDC's Dr. Tom Shimabukuro.

"What we have here is a picture of clots forming in large vessels where we have low platelets," Shimabukuro explained. "This usually doesn't happen," but it's similar to European reports with the AstraZeneca vaccine.

The clot concerns could undermine public confidence in a vaccine many hoped would help some of the hardest-to-reach populations — in poor countries or in places like homeless shelters in the U.S.

Health officials recommended the J&J timeout in part to make sure doctors know how to recognize and treat the unusual condition. On Wednesday, the CDC said four of the six women with the unusual clots were treated with a blood thinner named heparin — a treatment the government is warning doctors to avoid.

The U.S. set up intensive systems to track the safety of COVID-19 vaccines, knowing that side effects too rare to have occurred in studies of thousands of people could pop up once millions rolled up their sleeves. Shimabukuro said spotting such a rare potential risk amid the nation's huge vaccine rollout "is an example of a success story for vaccine safety."

File video: Infectious disease doctor says 'don't panic' about J & J vaccine pause

The six cases were among more than 6.8 million Americans who have received a dose of that vaccine.

"Less than 1 in a million," Dr. Anthony Fauci noted Tuesday during a White House briefing.

All six cases were among women between the ages of 18 and 48, the agencies said in a statement, and symptoms occurred six to 13 days after vaccination. The recommendation to pause comes out of "an abundance of caution," they added, and these cases "appear to be extremely rare."

"It makes sense now to pause, get a sense for whether this is a real phenomenon, whether it really is associated with the vaccine and who in particular might be at highest risk," Dr. Jonathan Reiner, a professor of medicine and surgery at George Washington University, told CNN on Tuesday.

Reiner added he worries the pause may contribute to further hesitancy about the vaccines being administered in the U.S.

"The way I want people to look at it is this: These vaccines are incredibly effective. You're much more likely to die of the coronavirus than you are to have a significant complication from these vaccines," he said.

So far, the J&J vaccine has been a minor player in U.S. vaccinations. More than 122 million Americans have received at least one vaccine dose, the vast majority with shots made by Moderna or Pfizer, and nearly 23% are fully vaccinated.

CNN contributed to this report.

Vaccine advisers to the Centers for Disease Control and Prevention are meeting Friday to discuss how to move forward with Johnson & Johnson's Janssen coronavirus vaccine.

The Advisory Committee on Immunization Practices is scheduled to meet from 11 a.m. to 5 p.m. Friday and to vote on updated recommendations for use of the vaccine and whether it's likely to be linked to a rare blood clotting syndrome they're calling thrombosis with thrombocytopenia syndrome (TTS).

Other groups have called it vaccine-induced immune thrombotic thrombocytopenia or VITT, but the committee is sticking with more neutral language that doesn't presume vaccines are causing the condition.

It's characterized by a rare type of blood clot in the brain — and possibly other large blood clots — along with a low number of blood-clotting cells called platelets. Some blood specialists have said they believe it's caused by an unusual immune reaction that targets platelets, causing them to glob together into clots.

The committee will hear about any additional cases reported since their last meeting earlier in the month. The cases of six women who suffered TTS, including one who died, prompted CDC and the Food and Drug Administration to recommend a pause in giving the vaccine. Committee members said they needed more time and more information before deciding on whether and how to change recommendations for giving the vaccine.

They'll hear about at least one more case. Oregon health officials said Thursday night they were investigating the case of a woman in her 50s who died after having received the vaccine and who had symptoms of TTS.

"We are very much encouraged by the fact that our safety reporting systems are working," Dr. Shimi Sharief, senior health adviser with Oregon's health authority, told reporters in a briefing. She noted the coronavirus pandemic is ongoing and killing people.

"This is still extremely rare," she said -- noting that seven cases of blood clots had been reported out of nearly seven million J&J vaccines given, and two of those cases had been fatal.

They'll hear from a blood clot expert — Dr. Michael Streiff of Johns Hopkins University, who is likely to brief on what's known how to treat TTS. Reports indicate blood thinners, with the exception of a commonly used blood thinner called heparin — will help dissolve the clots, and use of an immune product called IVIG can help neutralize the mistaken immune response.

The committee will also hear from two officials of Johnson & Johnson.

Members of committee will consider the potential risks of the vaccine as opposed to the risk of catching coronavirus. Blood clot specialists have told CNN the risk of developing blood clots of all sorts from coronavirus infection are much higher than the risks seen in people who got the vaccine.

AstraZeneca's vaccine has been linked to TTS as well. The World Health Organization and European medical regulators have said the benefits of the AstraZeneca vaccine, which is not yet authorized in the U.S., outweigh any potential risks.

Earlier this week, Dr. William Schaffner, a non-voting committee member and infectious diseases professor at the Vanderbilt University School of Medicine, told CNN that the committee could recommend that use of the vaccine resume with no changes, or the committee could recommend that the U.S. stop using the J&J vaccine altogether.

Schaffner said it's more likely that the committee will recommend that use of the vaccine resume with a warning about possible adverse effects — and potentially, advice to the highest-risk populations to steer clear of this vaccine altogether.

Health advisors for the Centers for Disease Control and Prevention have recommended resuming the Johnson & Johnson COVID-19 vaccine.

A government advisory panel deliberated Friday on the issue after the CDC and FDA recommended a pause of the one-dose vaccine on April 13.

The government announced Friday night that the CDC and FDA are lifting the pause on the Johnson & Johnson vaccine after reviewing the data.

The committee's recommendation, approved 10-4, is that the J&J vaccine is recommended for persons 18 and older in the U.S. under the FDA’s emergency use authorization.

Health officials said Friday they were aware of 15 cases of the unusual clots since the government authorized use of the vaccine and nearly 8 million shots were given. All were women, most of them under 50. Three died, and seven remain hospitalized.

European regulators earlier this week allowed the rollout of J&J's shot after concluding those benefits outweigh what appears to be an exceedingly rare risk.

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. The CDC and Food and Drug Administration initially spotted six people who developed such clots one to three weeks after J&J vaccination. On Friday, health officials said nine more cases came to light in the last week or so.

File video: Doctor discusses next steps with Johnson & Johnson COVID-19 vaccine prior to advisory committee decision

The 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.

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. In the U.S., more than half of adults have received at least one vaccine dose, the vast majority with the Pfizer and Moderna shots.

But J&J mass vaccination clinics were canceled after the April 13 pause, and many states had been counting on the one-and-done option to also help protect hard-to-reach populations including people who are homeless or disabled.

J&J faces an additional hurdle, as 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.

COVID-19 itself can cause blood clots. So can everyday medications, such as birth control pills.

The Associated Press contributed to this report.

COVINGTON, Ky. — If you live in Northern Kentucky and still need to get your COVID-19 shot, a free vaccination clinic will be held Saturday at First Baptist Church in Covington.

Walk-ins are welcome for the clinic at 120 E 9th St. from 9:30 a.m. to 12:30 p.m.

The clinic, presented by the Northern Kentucky NAACP in partnership with NKY Health and St. Elizabeth Healthcare, will focus on diversity and immunizing underserved populations.

Two-dose Moderna and single-shot Johnson & Johnson vaccines are available at Saturday's clinic.