Updated Covid-19 vaccines boost protection, but may not beat ...

CNN —

The updated Covid-19 booster shots appear to work about as well against the BA.4 and BA.5 Omicron subvariants as the original boosters they replaced, according to two new studies from research teams at Harvard and Columbia universities.

The research suggests that our bodies have been well-trained to fight the original virus, which emerged from Wuhan, China, and that boosters mostly reinforce that response. Getting boosted this fall is still an important way to renew protection, even among people who were previously infected or vaccinated.

But the hope was that by tweaking the vaccine recipe to include currently circulating strains of the Omicron variant, it would help broaden immunity against those variants and perhaps offer better and longer-lasting protection.

When the researchers compared the immune responses of people who got a booster dose of the original shot to people who got the updated bivalent boosters, they looked about the same.

“We see essentially no difference” between the old boosters and the new about a month after the shot, said Dr. David Ho, professor of microbiology and immunology at Columbia, whose team authored one of the studies.

Immunologists say a vaccine against two strains may not be better than a single strain shot because of a phenomenon called immune imprinting. Scientists say imprinting may complicate efforts to stay ahead of new variants as the coronavirus continues to evolve, and it adds urgency to the development of new vaccine technologies to fight the virus.

When the US Food and Drug Administration issued emergency use authorizations for new bivalent Covid-19 vaccines from Pfizer and Moderna at the end of August, it did so on the basis of studies in mice and previous human trials with a different two-strain booster formulation. Little was known about the how protective the shots might be in people; full data from clinical trials testing the BA.4 and BA.5 bivalent vaccines in humans hasn’t yet been made public.

But modeling data suggested that getting the boosters out in September could save tens of thousands of lives if the country had another winter surge, so the FDA authorized the shots, ahead of results from clinical trials, in order to get them to the public more quickly.

The updated shots contain instructions that show cells how to make spike proteins from the original virus that caused Covid-19, as well as spikes from the BA.4 and BA.5 subvariants. These spikes get assembled by our cells and displayed to our immune system so it can make antibodies to fight the real thing during an active infection.

The original strain of the virus, sometimes called the ancestral or wild-type strain, is no longer circulating, however. When we boost, we are mostly boosting antibodies against a virus that’s long gone.

As the virus has evolved, the vaccines have not kept pace. Each new variant has become more and more resistant to the antibodies we make against it, increasing the risk of breakthrough infections, hospitalizations and deaths.

Right now, protection against infection begins to wane just a few months after each booster dose. Protection against severe outcomes – hospitalization or death from Covid-19 – lasts longer, but can also fade, especially for vulnerable groups such as people who are over 65, who have weakened immune systems or who have underlying medical conditions.

Similar immune responses

The studies have important limitations, and they aren’t the final word on the updated boosters.

Both studies were small. Ho’s study looked at the immune responses of 19 people who were boosted with a fourth dose of the original recipe vaccine and 21 people who got a fourth dose of the updated boosters. The other study, from Dr. Dan Barouch, a professor at Harvard and director of the Center for Virology and Vaccine Research at Beth Israel Deaconess Medical Center, looked at 15 people who got the original booster and 18 people who got bivalent shots.

Both reports were posted as preprints, before scrutiny by independent experts.

The studies also measured immune responses over a short period of time – about three to five weeks after the fourth doses. Ho says these results could change with time, as immune cells mature.

“We can’t say that a few months from now, there won’t be any difference,” he said. “We won’t know that until these individuals are followed for a longer period of time.”

Despite these caveats, experts who were not involved in the research say that two studies from well-regarded labs arriving at roughly the same conclusions about the vaccines gives them confidence that the results are correct.

“At least at this time point, there’s no discernible benefit” over the older boosters, Ho said.

Clinical trials being conducted by vaccine makers Pfizer and Moderna involve hundreds of people who have had the updated boosters and are being followed for longer periods of time. Data from those studies are still coming.

Both companies declined to comment on Ho and Barouch’s studies, citing company policies not to weigh in on research they have not been involved in.

In comparing the immune responses of people who got the old boosters with those who got the newer ones, the researchers found that neutralizing antibodies spiked after both shots to about the same high levels, which was good news.

In Barouch’s study, antibody concentrations were 15 times higher after the original boosters, rising from 184 to 2,829. They were 17 times higher after the updated shots, jumping from 211 to 3,693. The difference in antibody levels between shots didn’t pass a statistical test, however, so the results may have been due to chance.

More importantly, that slight difference in antibody levels probably wouldn’t protect people any better in the real world.

“We would not expect this to be clinically significant,” said Barouch, who worked on the development of the Johnson & Johnson Covid-19 vaccine.

But the bulk of the antibodies generated after either shot were ones that would bind the original virus, with fewer directed specifically against the BA.4 and BA.5 subvariants.

Barouch’s team also looked specifically at T cells, which help the body hold the memory of germs it has been exposed to. These cells are thought to play a key role in how long immune protection lasts. Antibody levels naturally drop off over time, but T cells stick around.

The numbers of T cells didn’t budge much after either vaccine.

“Unfortunately, neither one increased T-cell responses very much, and we believe that T-cell responses in addition to antibody responses are important for protection against severe disease,” Barouch said.

‘A booster is a booster’

Dr. Eric Topol, who directs the Scripps Research Translational Institute, said the study results “can be considered a disappointment,” especially because the US government raced to make them available and because there had been high hopes for an improved vaccine in time for a predicted winter Covid-19 surge.

Topol also said it would be a mistake to skip these shots. They still work; they just may not be much of an improvement over the older ones.

“A booster is a booster until proven otherwise and we are in great need of getting more of them in the US,” Topol, who was not involved in the new studies, wrote in an email to CNN.

Fewer than 20 million people – less than 10% of the population ages 5 and up – have gotten the updated booster, according to data from the US Centers for Disease Control and Prevention.

After waiting the recommended three months since his last Covid-19 infection, President Joe Biden got an updated booster Tuesday and urged eligible Americans to do the same.

“Your old vaccine or your previous Covid infection will not give you maximum protection,” Biden said.

Public health officials had hoped that the rollout of the updated boosters would mark a turning point, where Americans might be able to get annual Covid-19 shots instead of boosters every few months.

Dr. Peter Marks, director of the FDA’s Center for Biologics Evaluation and Research, recently told Stat that he wasn’t sure whether the country had reached that point.

“I would be lying to you if [I said] it doesn’t keep me up at night worrying that there is a certain chance that we may have to deploy another booster – at least for a portion of the population, perhaps older individuals – before next September, October,” he said.

“I’m not saying that’s what’s going to happen, but it’s what keeps me up at night, because we see how fast this virus is evolving.”

Imprinting may complicate quest for better immunity

The studies probably didn’t find any difference between the new and old boosters because of immune imprinting, says Michael Worobey, a professor at the University of Arizona who studies the evolution of viruses and the origins and control of pandemics.

“Your body is on a hair trigger to create more antibodies of what it has a good memory of,” said Worobey, who was not involved in the new research.

At the beginning of the pandemic, our immune systems were blank slates when it came to the coronavirus. By now, most of us have been exposed to one version of the virus or another through the vaccine, an infection or both. That exposure programs cells called B cells to make specific kinds of antibodies, and more B cells get this programming during their first exposure to the virus than they do in subsequent brushes with it.

That’s the reason some strains of the flu may hit certain age groups harder than others, too. When viruses look more similar to the first infection or vaccine you had, your body tends to do a better job fighting them off.

Worobey said that both new studies have limitations, “but I think when you put them together, they paint a pretty clear picture that that antigenic imprinting is causing issues here, for sure.”

It’s possible to break through immune imprinting, he said. Certain kinds of vaccine ingredients, or adjuvants – “things that just happen to really wake up the immune system” – can do it.

But it’s not easy to add the kind of adjuvants he’s thinking about to mRNA vaccines like Pfizer and Moderna’s. In this case, he says, judging by the study findings, it probably would have been better to update the vaccine by including only the components against BA.4 and BA.5.

“For me, the take-home message is, if you want to boost and provide protection against Omicron, leave the original variant out of the vaccine.”

Dr. Paul Offit, director of the Vaccine Education Center at the Children’s Hospital of Philadelphia and a member of the FDA’s vaccine advisory committee, says the new studies bear out data that was presented to the FDA’s advisers in June.

He says it’s one of the reasons he voted against the FDA requiring companies to add an Omicron strain to the boosters used in the US.

“Certainly, the hope that this would be significantly better in terms of protection against the circulating strains, I think, is unlikely to be realized,” said Offit, who was not involved in the new studies.

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Worobey says that when the strains are combined as they are in the updated boosters, they actually end up competing. The body’s response to the original strain is so strong, it will end up blocking the updated portion of the vaccine from stimulating those blank slate B cells against the newer variants and reshaping the immune response.

Thus, imprinting will complicate efforts to keep up with the virus, he says. We may need different kinds of vaccine technologies if the virus ever changes so much that it outcompetes our immunity altogether.

That’s something the FDA’s Marks has considered, too.

“I would love to see us have a very ecumenical look over all of the available vaccines and all of the vaccines in development to try to see what’s best moving forward,” he told Stat. “Not to diss the current mRNA vaccines but because we owe it to the population to see what might provide the greatest breadth, depth and duration of immunity against Covid-19.”

Pfizer/BioNTech Covid-19 vaccine: Protection against infection ...

CNN —

A fourth dose of the Pfizer/BioNTech Covid-19 vaccine seems to offer short-lived protection against infection overall, but protection against severe illness did not wane for at least several weeks, according to a new study.

The study, published Tuesday in the New England Journal of Medicine, looked at the health records of more than 1.25 million vaccinated people in Israel who were 60 or older from January through March 2022, a time when the Omicron coronavirus variant was the dominant strain.

The rate of severe Covid-19 infection in the fourth week after a fourth dose of vaccine was lower than in people who got only three doses by a factor of 3.5.

However, protection against severe illness did not seem to wane in the six weeks after the fourth shot, though the study period wasn’t long enough to determine exactly how long this protection lasts.

The rate of confirmed infection in the fourth week after the fourth dose was lower than in the three-dose group by a factor of 2. There seemed to be maximum protection against Omicron in the fourth week after vaccination, but the rate ratio fell to 1.1 by the eighth week, suggesting that “protection against confirmed infection wanes quickly,” the study says.

The protection provided by any vaccine naturally wanes, but a vaccine primes the immune system to make protective antibodies if it encounters threats later on.

The currently available Covid-19 vaccines were made to protect against the original strain of the virus. Omicron is significantly different, and therefore, vaccines have lost some of their effectiveness. Israel and the US are among the governments that have suggested fourth vaccine shots for certain people who are at high risk of severe illness, like those who are older.

Last week, the FDA expanded its emergency use authorization to allow adults 50 and older to get a second booster shot as early as four months after their first booster of a Pfizer or Moderna vaccine. People with certain immune deficiencies can also get a fourth dose in the US. But the debate continues about whether one is needed for the general population.

The US Food and Drug Administration’s independent vaccine committee meets Wednesday to discuss what the country’s booster strategy should be going forward. Some experts have suggested that the Covid-19 vaccine could become an annual shot like the flu vaccine.

There are limits to what the new research can say about the need for a fourth vaccine dose. It compares only protection provided by third and fourth doses, so it doesn’t include unvaccinated people for comparison. It also doesn’t add to the debate over whether people under the age of 60 may need a fourth dose. Previous research in Israel showed that a fourth dose didn’t do much in younger healthy populations, at least in terms of protection from infection.

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For confirmed infection, “a fourth dose appears to provide only short-term protection and a modest absolute benefit,” the researchers wrote. But when it comes to severe infection, the fourth shot seems to help.

“Overall, these analyses provide evidence for the effectiveness of a fourth vaccine dose against severe illness caused by Omicron variant as compared with a third dose administered more than four months later,” the study says.

Even with this news, it is unclear how many eligible people will get a fourth Covid-19 shot. About 66% of the US population has gotten at least one Covid-19 vaccine, but only 30% of people are fully vaccinated with a booster dose, according to the US Centers for Disease Control and Prevention.

Johnson & Johnson's Covid-19 vaccine worked better than it gets ...

CNN —

The US public and even some health experts may have underestimated the Covid-19 vaccine made by Janssen, a division of Johnson & Johnson, new data shows. And there’s emerging evidence that it could still play an important role ahead.

A study published Thursday in the medical journal JAMA Network Open found that the J&J vaccine remains durable and effective, even through the surge of cases caused by the Delta variant. It was 76% effective overall in preventing Covid-19 infections and 81% effective in preventing Covid-related hospitalizations. The study also showed that it provided lasting immunity at least six months after the shots.

And a CNN analysis of information collected by the US Centers for Disease Control and Prevention showed the J&J vaccine had the lowest breakthrough infection rate of all the vaccines since the week ending December 25, the latest five weeks of available data.

In January, during the Omicron surge, breakthrough infections were highest among those who received the Pfizer/BioNTech vaccine, followed by those who got Moderna. Those vaccinated with the Johnson & Johnson shot had the lowest incidence of breakthrough infections.

As of the week ending January 22, there were 650 infections per 100,000 people with the J&J vaccine. With Moderna, there were 757 per 100,000, and with Pfizer, the rate was 862 per 100,000.

Unvaccinated people were particularly vulnerable to getting sick during the Omicron and Delta surges, just as they were with the original version of the coronavirus. They were 3.2 times as likely to get sick as people who had the J&J vaccine. The unvaccinated were 2.8 times as likely to become infected than those who got Moderna and 2.4 times as likely as those who got Pfizer.

“What we saw in the summertime and the fall during the Delta surge is that all three vaccines protected very, very well. But breakthrough rates in August, September of last year with the Janssen vaccine were slightly higher than Pfizer, and Moderna was slightly lower. But those differences were relatively small,” said Dr. Dan Barouch, director of the Center for Virology and Vaccine Research at Beth Israel Deaconess Medical Center in Boston. He helped to develop and study the J&J vaccine.

“But what we saw over time is that those differences then narrowed,” he said. “And by the first week of December, what we saw in the data is that the lines cross,” with incidence rates for the J&J/Janssen vaccine becoming lower than the others.

‘Reassuring’ data for J&J recipients

In March 2021, the J&J vaccine was the third to be authorized by the US Food and Drug Administration, and the initial response was more muted than the milestone authorizations of the mRNA vaccines from Pfizer/BioNTech and Moderna.

The vaccines work differently. The mRNA vaccines deliver blueprints, essentially, that train your body trains to fight that particular infection and any similar infection down the road. Adenovirus-vector vaccines, like J&J’s, use a virus that can act like a Trojan horse. But instead of soldiers jumping out, the adenovirus releases genes that encode the coronavirus’ spike protein.

The J&J vaccine stood out for other reasons, too: It came as a convenient single dose and didn’t require special refrigeration, whereas the mRNA vaccines required two doses, and Pfizer’s needed special cold storage. The flexibility was appealing for people who were afraid of shots or didn’t have the time to get two shots. It was also better for countries without a solid health care infrastructure.

But its performance tempered some of the enthusiasm around it, especially from the public.

Whereas the mRNA vaccines were hailed for “astonishing” efficacy of more than 90%, the news that J&J was 65% effective at preventing symptomatic Covid-19 among clinical trial volunteers underwhelmed some.

From the start, the J&J vaccine supply was more limited. After after the vaccine was authorized, the federal government briefly paused its use due to safety concerns around rare blood clotting events. Even once vaccinations resumed, the pace of J&J vaccinations never recovered.

In December, the CDC changed its recommendations to say shots made by Moderna and Pfizer/BioNTech are preferred over J&J’s. It also urges people who got the J&J shot to get a booster of one of the mRNA vaccines two months later.

The protection that the Covid-19 vaccines offered has waned over time, and none of them works as well against the variants that have popped up since the original coronavirus surfaced. But the science is starting to show that people who got the J&J Covid-19 vaccine may have some advantage.

Barouch told CNN that he “wasn’t surprised at all” to see that the durability of the Johnson & Johnson vaccine appears to be last longer than that of the mRNA vaccines – Pfizer/BioNTech and Moderna – based on the incidence of breakthrough infections.

The mRNA vaccine technology has been shown to quickly elicit a potent and robust immune response after vaccination, but that can wane over time. Johnson & Johnson’s virus-vector platform may not spark as powerful of an immune response in the short term, but it is known to have strong durability.

“Over time, the efficacy of the Pfizer and Moderna vaccines goes down, the efficacy of the J&J vaccines remains stable, and so it is exactly as you would predict: that they will converge and they will then cross,” Barouch said.

The J&J vaccine also might have “a particular edge,” he said.

“The immune system is actually made of two arms: the antibodies side and the T cells. And the type of T cells that are critical for prevention of serious illness are called CD8 T cells,” Barouch said. “The J&J vaccine raises better CD8 T cells than the Pfizer and other mRNA vaccines, so the J&J vaccine might have a particular edge for variants like Omicron that largely escaped from antibody responses.”

Overall, Barouch called this data “very reassuring” for recipients of the J&J vaccine.

“They should be reassured that they received a vaccine that gives very good protection for a long period of time,” Barouch said. “And I think the second message is that I think people should learn about these new data in terms of considering booster shots, as well.”

Prospects as a booster?

David Montefiori, a virologist at Duke University Medical Center, said “the J&J vaccine has kind of gotten a bad rap because of the efficacy, but the stability of the response is intriguing.”

The antibody level went down with every vaccine during the Omicron surge, and that could mean people need an additional booster. More research is needed to find out.

A yet-unpublished study by the National Institutes of Health looking at a mix-and-match vaccine strategy saw good results when J&J was included, Montefiori said.

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“In people who got the Pfizer vaccine initially and then a boosted with the J&J vaccine, those people made pretty high levels of neutralizing antibodies to Omicron: 10 times higher than people who got two shots with just the J&J vaccine,” he said. “So the J&J vaccine might be a good booster for people who got an mRNA vaccine initially.”

The Johnson & Johnson vaccine can be used for primary doses or as a booster, but the CDC says the Pfizer and Moderna vaccines are recommended in most situations because of the risk of serious adverse events with the Johnson & Johnson vaccine.

The J&J vaccine has been linked to rare cases of blood clots with low platelets, known as thrombosis with thrombocytopenia syndrome or TTS. “It occurs at a rate of about 3.83 cases per million Janssen doses and has resulted in deaths,” the CDC says.

Dr. Angela Branche, an infectious disease specialist and associate professor of medicine at the University of Rochester, said the side effect profile of the J&J vaccine “remains something that’s of concern for some groups where that risk is high.” Women ages 30 to 49 years are at increased risk of this rare adverse event, the CDC says.

But if that research pans out, the J&J vaccine may be useful as a booster for only certain populations.

“For some groups where that risk of developing serious blood clots is not very high, like older adults, this may be a good strategy,” Branche said.

Montefiori said the vaccine deserves more study.

“I think there might still be a place for the J&J vaccine in the long-term picture of this pandemic,” Montefiori said.

Jen Christensen Deidre Mcphillips
Jen Christensen
Deidre Mcphillips

Updated boosters add limited protection against Covid-19 illness ...

CNN —

Updated Covid-19 boosters that carry instructions to arm the body against currently circulating Omicron subvariants offer some protection against infections, according to the first study to look at how the boosters are performing in the real world. However, the protection is not as high as that provided by the original vaccine against earlier coronavirus variants, the researchers say.

Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, called the new data “really quite good.”

“Please, for your own safety, for that of your family, get your updated Covid-19 shot as soon as you’re eligible to protect yourself, your family and your community,” Fauci said at a White House briefing Tuesday.

Uptake of the bivalent boosters, which protect against the BA.4/5 subvariants as well as the original virus strain, has been remarkably slow. Only 11% of eligible Americans have gotten them since they became available in early September.

The new study found that the updated boosters work about like the original boosters. They protect against symptomatic infection in the range of 40% to 60%, meaning that even when vaccine protection is its most potent, about a month after getting the shot, people may still be vulnerable to breakthrough infections.

That’s in about the same range as typical efficacy for flu vaccines. Over the past 10 years, CDC data shows, the effectiveness of the seasonal flu vaccines has ranged from a low of 19% to a high of around 52% against needing to see a doctor because of the flu. The effectiveness varies depending on how similar the strains in the vaccine are to the strains that end up making people sick.

The authors of the new study say people should realize that the Covid-19 vaccines are no longer more than 90% protective against symptomatic infections, as they were when they were first introduced in 2020.

“Unfortunately, the 90% to 100% protection was what we saw during like pre-Delta time. And so with Delta, we saw it drop into the 70% range, and then for Omicron, we saw it drop even lower, to the 50% range. And so I think what we’re seeing here is that the bivalent vaccine really brings you back to that sort of effectiveness that we would have seen immediately after past boosters, which is great. That’s where we want it to get,” said Dr. Ruth Link-Gelles, an epidemiologist at the US Centers for Disease Control and Prevention.

Vaccines are only one tool to stay well

“This protection is not 100%, but it is something,” Link-Gelles said. “Especially going into the holidays where you’re likely to be traveling, spending time with elderly relatives, with vulnerable people. I think having some protection from infection and therefore some protection from infecting your loved one is better than having no protection at all.”

Link-Gelles says it also means that people should continue to adopt a layered approach to protection, utilizing rapid tests, good-quality masks and ventilation as a comprehensive approach, rather than relying on vaccines alone.

“This should be sort of one of the things in your toolbox for protecting yourself and your family,” she said. “Personally, we’re my family is all vaccinated up to date, but I think if we go to the airport tomorrow, we’ll be wearing our N95 [masks] because we’re seeing elderly relatives this weekend. And while we of course trust the vaccines, and I’m not super worried about a mild infection in myself or my healthy husband, we certainly would not want to infect his grandmother.”

Link-Gelles added that she expects that vaccine protection against severe outcomes from Covid-19, like hospitalization and death, will be higher, but that data isn’t in yet.

The study, which was led by CDC scientists, relied on health records from more than 360,000 tests given at nearly 10,000 retail pharmacies between Sept. 14 and Nov. 11, a period when the BA.4 and BA.5 subvariants were causing most Covid-19 infections in the US. The study included people ages 18 and up who had Covid-19 symptoms and were not immunocompromised.

The study looked at how effective the boosters were in two ways: Researchers calculated a value called absolute vaccine effectiveness, which compared the odds of symptomatic infection in people who received bivalent boosters with those who reported being unvaccinated. They also calculated relative vaccine effectiveness, which looked at the odds of symptomatic infection in people who received updated bivalent boosters compared with those who had two, three or four doses of the original single-strain vaccine.

Compared with people who were unvaccinated, adults 18 to 49 who had gotten bivalent boosters were 43% less likely to get sick with a Covid-19 infection. Older adults, who tend to have weaker immune function, got less protection. Those ages 50 to 64 were 28% less likely, and those ages 65 and up were 22% less likely to get sick with Covid-19 than the unvaccinated group.

The relative vaccine effectiveness showed the added protection people might expect on top of whatever protection they had left after previous vaccine doses. If a person was two to three months past their last vaccine dose, the bivalent boosters added an average of 30% protection for those who were ages 18 to 49, 31% more protection if they were 50 to 64, and 28% more protection if they were 65 or older. At 3 months after their last booster, people ages 50 and older still had about 20% protection from Covid-19 illness, CDC data show. So overall, the updated boosters got them to around 50% effectiveness against symptomatic infection.

If a person was more than eight months away from their last vaccine dose, they got more protection from the boosters. But Link-Gelles said that by eight months, there was little protection left from previous shots against Omicron and its variants, meaning the vaccine effectiveness for this group was probably close to their overall protection against infection.

Those ages 18 to 49 who were eight months or more past their last dose of a vaccine had 56% added protection against a Covid-19 infection with symptoms; adults 50 to 64 had 48% added protection, and adults over 65 had 43% added protection, on top of whatever was left from previous vaccinations.

Short, modest protection from boosters

John Moore, an immunologist and microbiologist at Weill Cornell Medicine, said it boils down to the fact that that boosters will probably cut your risk of getting sick by about 50%, and that protection probably won’t last.

“Having a booster will give you some additional protection against infection for a short term, which is always what we see with a booster, but it won’t last long. It’ll decline, and it will decline more as the more resistant variants spread,” said Moore, who was not involved in the new research.

The immunity landscape in the United States is more complex than ever. According to CDC data, roughly two-thirds of Americans have completed at least their primary series of Covid-19 vaccines. And data from blood tests shows that almost all Americans have some immunity against the virus, thanks to infection, vaccination or both.

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A new preprint study from researchers at Harvard and Yale estimates that 94% of Americans have been infected with the virus that causes Covid-19 at least once, and 97% have been infected or vaccinated, increasing protection against a new Omicron infection from an estimated 22% in December 2021 to 63% by November 10, 2022. Population protection against severe disease rose from an estimated 61% in December 2021 to around 89%, on average, this November.

All of this means the US is in a better spot, defensively at least, than it ever has been against the virus – which is not to say that the country couldn’t see another Covid-19 wave, especially if a new variant emerges that is very different from what we’ve seen, if immunity continues to wane or if behavior shifts dramatically.

COVID-19 boosters, Dodgers vs. Giants, Banksy sale: 5 things to ...

Editors

USA TODAY

FDA experts to discuss boosters for Moderna, J&J COVID-19 vaccines

A federal advisory committee is meeting Thursday and Friday to discuss the safety and need for a booster shot for people who received Moderna's or Johnson & Johnson's COVID-19 vaccine. The panel also will hear data on people who got booster shots from a different manufacturer than their original vaccine. The Centers for Disease Control and Prevention last month endorsed booster shots for millions of Americans who got the Pfizer-BioNTech vaccine after Israeli data suggested protection against infection begins to wane after about six months. The FDA panel will vote on whether to authorize more boosters, but not on mixing vaccines. Assuming the FDA commissioner signs off on the group's recommendations, a CDC committee will consider on Oct. 20 and 21 who should be eligible for boosters, with the shots likely becoming available within a few days.

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Officers who died in the line of duty to be honored in Washington, D.C.

Fallen officers will be honored at a vigil at the National Law Enforcement Officers Memorial in Washington, D.C. Thursday. Hundreds of names were engraved there this year, bringing the total of officers memorialized to 22,611, per the National Law Enforcement Memorial Fund. But the names of four officers who died by suicide after defending the Capitol on Jan. 6 — U.S. Capitol Police Officer Howard Liebengood and District of Columbia Metropolitan Police officers Jeffrey Smith, Kyle DeFreytag and Gunther Hashida — won't be eligible for engraving on the marbleized limestone regarded as sacred ground for U.S. law enforcement. The Capitol attack, and the suicides that followed, reignited a discussion about what constitutes a job-related death and the policies that some say perpetuate a bias that law enforcement has failed to confront.

Suspect in deadly Norway bow and arrow attack was flagged for radicalization

A 37-year-old Danish man is in custody in Norway suspected of a bow and arrow attack Wednesday evening that left five people dead and two wounded in the small Norwegian town of Kongsberg. Police said Thursday that the man is a Muslim convert who had previously been flagged as having being radicalized. The man is suspected of having shot at people in a number of locations. Several of the victims were in a supermarket, police said. Acting Prime Minister Erna Solberg described the attack as “gruesome." Mass killings are rare in Norway. The country’s worst peacetime slaughter was on July 22, 2011, when right-wing extremist Anders Breivik set off a bomb in the capital of Oslo, killing eight people. He then headed to the tiny Utoya Island where he killed another 69 victims. Breivik was sentenced to 21 years in prison, the maximum under Norwegian law, but his term can be extended as long as he’s considered a danger to society.

Dodgers, Giants meet in Game 5 of epic division race

The Los Angeles Dodgers and San Francisco Giants know each other all too well. After all, they've been playing each other 131 years, and this year's epic division race wasn’t decided until the 162nd game of the regular season. Each team has won 109 games this season, including the postseason. On Thursday night in San Francisco (9:07 p.m. EDT, TBS), they'll meet one last time to decide the best-of-five National League Division Series. The winner will play the Atlanta Braves in the National League Championship Series. The Dodgers send 25-year-old Julio Urias, MLB's only 20-game winner this season, to the mound, while the Giants counter with 24-year-old Logan Webb.

Half-shredded Banksy up for auction again

A Banksy artwork that self-shredded just after it sold for $1.4 million is up for sale again Thursday — at several times the previous price. Auction house Sotheby’s said that “Love is in the Bin” will be up for bid in London, with a pre-sale estimate of $5.5 to $8.3 million. It consists of a half-shredded canvas bearing a spray-painted image of a girl reaching for a heart-shaped red balloon. Just as an anonymous buyer made the winning bid in 2018 for what was then known as "Girl With Balloon," a shredder hidden in the frame whirred to life, leaving half the canvas hanging in strips. The buyer decided to go through with the purchase — a decision that would be vindicated if the picture achieves its estimated price.

Contributing: The Associated Press

Potential for fourth Covid-19 vaccine dose is being 'very carefully ...

CNN —

As the world approaches the second anniversary of the declaration of the Covid-19 pandemic by the World Health Organization, on March 11, more nations are rolling out – or are discussing the possibility of – fourth doses of coronavirus vaccine for their most vulnerable. In the United States, leading public health officials say they are “very carefully” monitoring if or when fourth doses might be needed.

Israel was the first nation to roll out fourth doses, announcing in December that adults 60 and older, medical workers and people with suppressed immune systems were eligible to receive the extra shot if at least four months have passed since their third dose.

More recently, the Public Health Agency of Sweden announced last week that second booster doses are recommended for everyone 80 and older in the country. The United Kingdom’s Department of Health and Social Care announced Monday that an extra booster dose of coronavirus vaccine will be offered in the spring to adults 75 and older, residents in care homes for older adults and immunosuppressed people 12 and older.

In the United States, health officials emphasized late last year that fourth doses were not yet needed and said it was too premature to be discussing a potential fourth dose of coronavirus vaccine for most people.

Now, the US Food and Drug Administration “is indeed continually looking at the emerging data on the pandemic and variants in the United States and overseas in order to evaluate the potential utility and composition of booster doses,” FDA spokesperson Alison Hunt wrote in an email to CNN on Friday.

She confirmed that although Dr. Peter Marks, director of the FDA’s Center for Biologics Evaluation and Research, has noted that there is still much uncertainty as to how the pandemic may further evolve, he also has said it is possible that a fourth dose might be recommended as we move into fall.

A fall timeline coincides with the administration of flu shots, which could be convenient for people and makes sense scientifically because respiratory viruses – like the coronavirus and influenza – tend to peak in the winter months that follow.

“As more data become available about the safety and effectiveness of COVID-19 vaccines, including the use of a booster dose, we will continue to evaluate the rapidly changing science and keep the public informed,” Hunt wrote. “Any determination that additional booster doses are needed will be based on data available to the agency.”

If or when the FDA authorizes a fourth dose for the public, the next step would be for the US Centers for Disease Control and Prevention to review the data before making a recommendation for use, as the agency has done for other coronavirus vaccine recommendations.

‘Vaccination and boosting will be critical’

The United States has seen significant improvements recently in Covid-19 cases, hospitalizations and deaths. As of Friday, cases were down 44% from the prior week, hospitalizations dropped 26%, and deaths were 13% lower, according to Johns Hopkins University data.

“Vaccination and boosting will be critical in maintaining that downward trajectory, particularly when you’re talking about the red curve of severe disease leading to hospitalization,” Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, said during a White House Covid-19 Task Force briefing Wednesday.

The “potential future requirement” for an additional boost or a fourth shot of the Pfizer/BioNTech or Moderna mRNA vaccines or a third dose of the Johnson & Johnson vaccine “is being very carefully monitored in real time,” Fauci said. “And recommendations, if needed, will be updated according to the data as it evolves.”

The CDC has no recommendation of fourth doses of coronavirus vaccine for the general public, but the agency updated its guidelines in October to note that certain people who are moderately or severely immunocompromised may receive a fourth dose of the Moderna or Pfizer/BioNTech vaccines.

“For the immunocompetent people, a single booster shot continues to provide high levels of protection against severe disease caused by Omicron,” Fauci said Wednesday. “This should not be confused with the fact that for many immunocompromised people, already a second booster shot – namely a fourth dose of an mRNA – is recommended because of what we know about their poor response to the initial regimen.”

Meanwhile, vaccine makers continue to study fourth doses in broader populations.

‘We recognize the need to be prepared’

Pfizer announced in January that it has been studying the safety and efficacy of a fourth dose as part of its ongoing study of an Omicron-specific coronavirus vaccine among healthy adults ages 18 to 55.

For that study, participants have been separated into three cohorts. One includes 600 people who got three doses of the current Pfizer/BioNTech coronavirus vaccine before enrolling in the study. As part of the research, they will receive either a fourth dose of the current vaccine or a dose of the Omicron-based vaccine.

“While current research and real-world data show that boosters continue to provide a high level of protection against severe disease and hospitalization with Omicron, we recognize the need to be prepared in the event this protection wanes over time and to potentially help address Omicron and new variants in the future,” Kathrin Jansen, senior vice president and head of vaccine research and development at Pfizer, said in the company’s announcement of the study.

A study published by the CDC last week showed that protection against Covid-19 hospitalization and emergency department or urgent care visits is much higher after a third vaccine dose than a second dose but that protection wanes with time.

With the Omicron variant dominant in the United States, vaccine effectiveness was 87% against Covid-19 emergency department or urgent care visits and 91% against hospitalizations in the two months after a third dose. Effectiveness fell to 66% and 78%, respectively, by the fourth month, the data showed.

“Nonetheless, the level of 78 is still a good protective area,” Fauci said Wednesday.

Dr. Christopher Murray, director of the University of Washington’s Institute for Health Metrics and Evaluation, told CNN on Friday that he thinks having a fourth dose “makes very little sense” right now – but possibly makes more sense this upcoming fall or winter.

“Because Omicron is going away,” he said, “third dose immunity wanes, and so fourth dose will probably wane as well. So we would want to time a fourth-dose push for when either there’s a new variant or for next winter. So I think right now, unless you’re immunocompromised or you’re older, unless you have some personal risk, it doesn’t make a lot of sense.”

The research showing some waning immunity after a third dose has led to more discussion around if or when fourth doses could be needed.

“Just like with everything else, the health departments look at this data that’s coming out and wait for guidance from the CDC and from the drug manufacturers. The drug manufacturers have been monitoring vaccine effectiveness,” Lori Tremmel Freeman, chief executive officer of the National Association of County and City Health Officials, told CNN on Friday.

The timing for fourth doses not only depends on waning immunity “but also depends on whether we see any more variants emerge and what we discover in terms of additional vaccine effectiveness for any emerging new infections,” Freeman said.

If fourth doses are needed, “health departments would go into the mode of preparing to administer the fourth dose in the way they have done previous doses,” Freeman said. However, of greater concern among local public health officers is the slow – and declining – pace of people completing their third doses, she said.

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About 65% of the US population is fully vaccinated with at least their initial series, and about 28% of the population has received a booster dose, according to the CDC, as of Friday. But the pace of booster doses being administered has dropped to one of the slowest rates yet.

“As time goes on, if there is the necessity of a fourth dose, we’re already behind with people getting the third dose,” Freeman said. “So all of a sudden, we could have a fairly large segment of the population that is not up to date on vaccines because they’re behind by two doses, potentially, and more people could get sick.”

COVID vaccine booster shots coming Sept. 20, Biden administration ...

WASHINGTON – The Biden administration on Wednesday unveiled plans to begin offering COVID-19 booster shots this fall for American adults who received the Pfizer or Moderna vaccines, eight months after they become fully vaccinated, as cases of the delta variant continue to spread across the country.

Americans who are eligible can receive a third shot beginning Sept. 20, pending authorization from the U.S. Food and Drug Administration, which is expected in the coming weeks, according to a statement from the Department of Health and Human Services and other administration medical experts.

"It is now our clinical judgement that the time to lay out a plan for Covid-19 boosters is now. Recent data makes clear that protection against mild and moderate disease has decreased over time," US Surgeon General Dr. Vivek Murthy said.

The initial doses will go to those who were fully vaccinated earliest in the vaccine rollout, including health care providers, nursing home residents and other seniors. The administration plans to also begin delivering booster shots directly to residents of long-term facilities, according to the statement.

The announcement comes as the highly contagious delta variant now accounts for more than 98.8% of U.S. cases, according to the Centers for Disease Control and Prevention.

Officials emphasized that mRNA vaccines like Pfizer and Moderna continue to be effective in reducing risk of hospitalization and death, but conceded that recent data made clear that protections begin to wane after the initial doses and amid the dominant delta variant.

COVID and kids:The delta variant of COVID-19 is more contagious for children. Is it making them sicker, too?

Biden administration changes its advice on boosters

Officials said they anticipate booster shots will likely be needed for people who received the Johnson & Johnson shot, but acknowledged that they're still collecting data as the federal rollout of the vaccine did not begin in the U.S. until March.

Johnson & Johnson shots:'Naked in the world of COVID': Some J&J vaccine recipients feel unprotected against delta and want mRNA shots

President Joe Biden is expected to speak later Wednesday on the new recommendation. His remarks come less than a week after the CDC issued a recommendation for booster shots for some immunocompromised people, or about 3% of the U.S. population.

Administration officials had previously said there was no need for a booster shot to protect against the delta variant.

“No American needs a booster now,” Biden said last month. “But if the science tells us there’s a need for boosters, then that’s something we’ll do. And we have purchased the supply – all the supply we need to be ready if that was called for.”

More:'This will be a tough year': Thousands of kids are in COVID-19 quarantine across the US, and school has just begun

Should US offer third shot or donate vaccines?

Some global health advocates have criticized the recommendation for a third shot, arguing that the U.S. should focus more on donating its supply of coronavirus vaccines to low-income countries that are still struggling to inoculate their populations.

"As wealthy countries debate when to give third shots, many African countries still don't have enough vaccines to give all of their immunocompromised citizens and first responders one dose,” said Edwin Ikhuoria, Africa Executive Director, The ONE Campaign. "Wealthy nations must do more to increase global access to vaccines as soon as possible. Lives and livelihoods depend on it.”

Officials acknowledged they will need to balance offering booster shots against its campaigns to get more people vaccinated at home and abroad.

"We will continue to ramp up efforts to increase vaccinations here at home and to ensure people have accurate information about vaccines from trusted sources," the statement read. "We will also continue to expand our efforts to increase the supply of vaccines for other countries, building further on the more than 600 million doses we have already committed to donate globally.”

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Data from Israel, Mayo Clinic prompted booster offering

The policy change comes because of data released from Israel and the Mayo Clinic, among others, said Dr. Eric Topol, vice president for research at Scripps Research in La Jolla, California, and a national expert on the use of data in medical research.

Data published by Israel’s Ministry of Health show that protection from the Pfizer/BioNTech vaccine dropped off precipitously after six months, down to 40-50% effectiveness against infection, he said. The vaccine was still highly protective against serious illness and death, but not against milder COVID-19.

Reports from Qatar and the Mayo Clinic are seeing the same effect, he said.

“It gets down to the 40 to 50% effectiveness range, whereas it used to be 95%,” he said.

Contributing: Elizabeth Weise, USA TODAY

Ready for 16- to 17-year-olds to get a COVID-19 booster? What you ...

The Food and Drug Administration last week gave emergency use authorization for COVID-19 Pfizer booster shots for 16- and 17-year-olds. Previously, the authorization had been only for people 18 and older.

The Centers for Disease Control and Prevention followed suit and recommended boosters for everyone 16 and older.

As with those 18 and older, people ages 16 and 17 receive a 30-microgram dose of Pfizer, the same as the first two shots. The booster can be given six months after a second shot. The Moderna and Johnson & Johnson vaccines have not been authorized for people younger than 18.

We asked Dr. Stanley Spinner, vice president and chief medical officer at Texas Children’s Pediatrics and Texas Children’s Urgent Care, about boosters in this age group and when boosters for those younger than 16 will be allowed.

New variant:What is the omicron COVID-19 variant, and should we be worried?

Why should 16- and 17-year-olds get a booster?

"We want to make sure they maintain that higher protection," Spinner said of those 16 or older who had a COVID-19 vaccination at least six months ago.

The data show that antibody levels begin to wane around six months after the second vaccination. The higher protection is important for the delta variant, which is the predominant variant right now and caused a surge in cases in the summer.

It's also been shown to be important for the new omicron variant. "We are learning that we need that booster to get added protection," Spinner said.

With the delta variant, one person could infect five to eight people. The omicron variant is thought to have at least double the transmission rate of delta, Spinner said.

Locally, the transmission rate (the amount of COVID-19 disease in an area) is slowly rising as is the number of people hospitalized with COVID-19.

"Get that booster dose as soon as they can," Spinner urged.

Having had COVID-19 doesn't give you as much protection as being vaccinated and getting a booster, he said.

Vaccines in kids:Worried about child's future fertility and COVID-19 vaccine? Know the truth about the risks

What is the magic of six months after your last shot?

"It's not like before six months, you're OK, and six months plus one day, you're not," Spinner said.

What scientists have noticed in studies is that there's a gradual reduction in antibody levels, and beyond six months, there's a measurable decrease. This reduction makes you more likely to get infected and possibly more likely to be sicker if you are infected, Spinner said.

They've also noticed that length of time after the second shot makes a difference in who is having breakthrough cases and even hospitalizations.

"By giving that third dose, it increases the measurement of antibodies, which correlates with better protection," he said.

Holiday safety:Ready to holiday? Before you gather with family and friends, think about COVID-19 safety

Why weren't ages 16 and 17 part of the initial booster group?

The FDA looks at data for a certain time period to see how well the booster works and to note any side effects, Spinner said.

When the recommendation for boosters for everyone 18 and older came down in November, we didn't yet have enough data for ages 16 and 17, he said.

When will boosters be recommended for 12- to 15-year-olds?

That group was approved for the Pfizer COVID-19 vaccine in May. Those in the first wave of vaccinated 12- to 15-year-olds are now at the six-month window.

The FDA is evaluating data to look at boosters for that age group, Spinner said. Researchers will look for efficacy and safety of the boosters and make their recommendations.

"It won't be much longer, probably," Spinner said.

For that group and anyone who is not yet fully vaccinated with a booster, it's important to weigh the risks of each event you attend.

"The more places you go with people that don't have the ultimate protection of a booster, yet there's more people around, especially indoors where it's crowded, there's more risk," he said.

Getting kids vaccinated:In Westlake and Lake Travis area, many parents of young kids jump on vaccine appointments

What about side effects for the newest group of vaccinated, ages 5 to 11?

One of the concerns with that age group was possible side effects that were seen in the teens and younger adults.

"We're actually seeing less side effects in that group than in adolescents and the adult group," Spinner said.

The most common were being tired, sore and achy, but this group has had less fever and less joint pain.

"It's partly because younger kids tolerate it better," he said, but it also could be that this group is getting one-third of the dose, or 10 micrograms instead of 30 micrograms. Pfizer is now studying whether that dosage is effective in ages 12-17.

When will kids 4 and younger get a COVID-19 vaccine?

Spinner and his colleagues think Pfizer and the FDA will break this age group into two: ages 2 to 4, and 6 months to 23 months.

The data for ages 2-4 will probably be submitted in January or February, he said. If that goes well, they will consider the youngest group a few months after that.

How much longer will this pandemic last?

COVID-19 is not going to go away.

"The expectation is that we will go from a pandemic, where it's everywhere all the time, to an endemic like the flu, where there are times of the year when people tend to be more inside together, when it may peak and then come down again," Spinner said.

Right now, flu is back in clinics and emergency rooms, he said, and that is why it's important to get a flu shot, too.

The hope is that through vaccination, we have enough community protection to get mild COVID-19 cases like with the flu, and that it doesn't overburden the hospital system, he said.

By getting as many people vaccinated and then boosted, "we make it more manageable to do the things we normally do without thinking about COVID," he said.

COVID vaccines near me: Where to get booster shots in Florida

The coronavirus pandemic in Florida is an evolving news story so some information in this article could be out of date. To stay connected with our comprehensive coverage of COVID-19 in Florida, sign up for our Coronavirus Watch newsletter.

If you've been vaccinated against COVID-19, you may need a booster shot, and Publix, CVS, Winn-Dixie and other locations have started offering them. Here's what you need to know to get one.

Do I need a COVID booster shot?

You almost certainly will. Studies have shown that protection against COVID-19 infection begins to wane about six months after the initial shots, although hospitalization or death for vaccinated people is still rare.

This dropoff is pretty common for vaccines, which is why you get a flu shot every year.

People over 65 are most at risk for severe disease, which is why the Advisory Committee on Immunization Practices (ACIP) voted unanimously to recommend to the U.S. Food and Drug Administration (FDA).that they authorize boosters.

"If you got the Pfizer vaccine in January, February and March of this year and you're over 65 years of age, go get the booster," President Joe Biden said. "Or if you have a medical condition like diabetes or you're a front-line worker, like a health care worker or a teacher, you can get a free booster now."

However, most vaccinated Americans remain well protected by the shots they already received, committee members and CDC officials said, and the best way to fight the pandemic is to get initial shots to people who have not yet received any,

More than 90% of those currently hospitalized with COVID-19 have not been vaccinated, they said.

Booster shots:More than 20M Americans are eligible for Pfizer-BioNTech booster shots. Should you get one?

Fact check:Why an FDA panel didn't recommend Pfizer's booster shot for all Americans

Who is eligible for a COVID booster shot?

So far, COVID-19 boosters shots of the Pfizer-BioNTech vaccine are available for people who completed their Pfizer shots at least six months ago* and meet the following conditions:

You are 65 years of age or older

You are 18 or over and you have underlying medical conditions such as cancer, chronic kidney disease, chronic lung disease, heart conditions, HIV infection, liver disease, obesity, sickle cell disease, smoking, solid organ transplant and stroke, among others. (Here's the list)

You are 18 or over and you work in high-risk conditions such as first responders, education staff, food and agriculture workers, grocery store workers and others. (Here's the list)

You are 18 or over and you live in high-risk settings such as health care, schools, correctional facilities, homeless shelters, or if you live with someone with underlying conditions or in an immunocompromised state.

*Note that this is not the same as a third shot for immunocompromised people. Immunocompromised individuals may receive a third dose of the Pfizer or Moderna vaccine as early as 28 days after their second dose.

Booster shot availability may be expanded in the future as researchers continue testing how well the vaccines are working for different groups of people.

High risk? Who is considered 'high risk' and eligible for Pfizer-BioNTech's booster shots?

Where can I get a COVID vaccine booster shot in Florida?

PUBLIX:Publix began offering Pfizer booster shots on Sept. 25 initially in Brevard, Duval, Orange and Polk counties, but within a day they were available for eligible recipients at all Publix Pharmacy locations in the state of Florida for walk-ins and appointments, according to a Publix press release

If you walk in, you must bring your driver license, insurance card, and CDC immunization card.

If you make an appointment online, be ready to provide the last four digits of your Social Security number, Medicare ID number (if applicable), state and county, and emergency contact name and number along with your contact information. You'll also be asked questions about your allergies and long-term health history.

WINN-DIXIE, FRESCO Y MÁS AND HARVEYS SUPERMARKETS: Grocery store pharmacies from the Southeastern Grocers chain are offering walk-up and online appointments. They're also offering a $10 coupon for getting a COVID-19 shot, and another for any other vaccine received the same day.

Appointments: Winn-Dixie | Fresco y Más | Harvey's

WALMART, SAM'S CLUB: Walmart and Sam's Club pharmacies are now administering third doses and boosters, with walk-ins and appointments.

CVS: CVS is offering booster shots at its 649 locations in Florida. You can schedule your appointment here.

Boosters are also available at select CVS MinuteClinic locations. Walk-in appointments are offered but they recommend scheduling your visit in advance due to potential kimited availability.

WALGREENS: Walk-ins are welcome at Walgreens, although they recommend you make an appointment. You can do that online or by calling 1-800-WALGREENS (1-800-925-4733).

REGIONAL LOCATIONS:

Many county-run sites either are or soon will be offering booster shots. Check with your local site for details.

Health First in Brevard County is offering a third dose on a walk-in basis only

The Florida A&M COVID vaccination site is now offering boosters

Residents of Seminole County can make appointments with PrepareSeminole.org

What's the difference between a third dose of the COVID vaccine and a booster shot?

Third shots are given to people with compromised immune systems who may not have gotten the full effect from the first two doses. They're considered part of the normal vaccination course for severely immunocompromised people.

The severely immunocompromised are often left unprotected by the two-dose vaccine regimen from Moderna and Pfizer-BioNTech, studies have shown. Roughly 40% to 44% of people hospitalized with severe COVID-19 infections after vaccination are immunocompromised, the CDC said.

Booster shots are intended to fight off the virus in people who have been fully vaccinated for at least six months but may be losing their protection against mild to moderate cases.

A third dose of the Pfizer-BioNTech vaccine is available for the immunocompromised as young as 12, while Moderna is allowed only for adults because that vaccine has not been authorized for use in minors.

For a third dose, people should try to get the same vaccine they received the previous two times, but they could switch between Pfizer-BioNTech and Moderna if necessary, the CDC said.

Third shots:Who should get a third COVID-19 vaccine shot? About 2.7M immunocompromised Americans, CDC says

Can I get a booster shot for the Moderna or Johnson & Johnson vaccine?

Not yet. At the moment, the FDA has only authorized boosters for the Pfizer vaccine, which has been fully licensed under the name Comirnaty.

Moderna has requested authorization for a lower dose of its initial vaccine to be used as a booster, which the FDA is currently considering and which could become available for boosters in coming weeks.

Johnson & Johnson, which has been a single-dose vaccine, released studies showing that a second dose is safe and improves effectiveness, but it has not yet submitted a request for FDA authorization to provide boosters.

Can I take the Pfizer booster if I received the Moderna or Johnson & Johnson vaccines?

The CDC advises against mixing the vaccines, and locations offering the boosters will not provide them to anyone who didn't initially receive the Pfizer vaccine. Researchers are studying the effects to see if mixing vaccines are effective but nothing has been approved.

Do I need to prove that I am high-risk to get a COVID vaccine booster shot?

You may need to prove your age if you are 65 or older, but if you're getting the booster because you belong in a high-risk category you don't need a doctor's note to request it, according to the CDC. Some locations may ask for a doctor's note anyway.

What if I can't find my COVID vaccination card?

If you've misplaced your COVID vaccination card or didn't receive one, contact the clinic, pharmacy, or other place where you received your vaccine to find out how to get a replacement. They can print you out a new card from your records.

If you received your shots with a registered Walgreens pharmacy account you can access your vaccine records online or through their mobile app. You can also access your records online if you received your shots from CVS, Walmart or Sam's Club.

If you can't contact your provider or you received your vaccination from a FEMA clinic, contact the Florida Healtjh Department's immunization information system at flshots@doh.state.fl.us or by calling 1-877-888-7468. All vaccination providers must report COVID-19 vaccinations to their IIS.

State health departments will either email or mail a copy of your vaccination card, although it may take one to two weeks.

If you registered with V-safe or VaxText after getting your shots, you can access your information through their apps.

Lost your COVID-19 vaccine card?:Don't worry, you can get a new one.

Vaccination cards:Lost your COVID vaccination card? Will you need a vaccine passport? Our FAQs on vaccine cards

Are COVID booster shots mandatory? Will I still be considered "fully vaccinated" if I don't get a booster shot?

Boosters are available – and free – but are not mandatory. A two-dose series of the Pfizer or Moderna vaccines, or one dose of the Johnson & Johnson vaccine, still counts as fully immunized.

Are there side-effects from getting the COVID booster shot?

According to the CDC, reactions to the booster are similar to getting the first shot of a 2-shot series or the one Johnson & Johnson vaccine: Fatique, pain at the injection site, etc. Most side effects were moderate but as with the first round of vaccines, serious side effects are rare but they may happen.

Why isn't the COVID vaccine enough by itself? Isn't it working?

The COVID vaccines are working very well, preventing severe illness, hospitalization and death against the virus and its variants. The vast majority of patients hospitalized in the latest surge have been unvaccinated.

But public health officials are starting to see reduced protection against asymptomatic, mild and moderate cases of the disease.

Data from clinial trials showed that a Pfizer booster increased the immune response for people who were completely vaccinated six months earlier. And Immunocompromised people, who may not have received the full benefit of the initial vaccines, have seen greatly improved immunization with a third shot.

C. A. Bridges is a Digital Producer for the USA TODAY Network, working with several newsrooms across Florida. Local journalists work hard to keep you informed about the things you care about, and you can support them by subscribing to your local news organization. Read more articles by Chris here and follow him on Twitter at @cabridges

Could the Covid-19 vaccine become an annual shot? Some experts ...

CNN —

Some scientists think we might be rolling up our sleeves each year not just for flu shots but for Covid-19 jabs too.

Public health experts aren’t quite clear on what the future holds for Covid-19 vaccines – but some say it’s looking more and more like these shots could be needed on a yearly basis, similar to how flu shots are recommended each fall.

“In order to keep it under control, we likely will need some form of periodic vaccination. Now, whether that’s annual or every two years or every five years, we don’t really know that yet. I think that that will emerge as we gather more data,” Dr. Archana Chatterjee, dean of the Chicago Medical School at Rosalind Franklin University, said Monday.

“But I do anticipate that this will be required on a periodic basis to keep it under control,” said Chatterjee, who’s also a member of the US Food and Drug Administration’s Vaccines and Related Biological Products Advisory Committee. She added that her comments do not reflect the opinions of the committee or the FDA.

The committee is scheduled to meet April 6 to discuss the need for Covid-19 vaccine booster doses in the future, including how often they might be needed – if at all.

The FDA said Monday that representatives from the US Centers for Disease Control and Prevention and the National Institutes of Health also will participate in the meeting.

The meeting is intended to assist the FDA in developing a “general framework” that will inform when further Covid-19 vaccine booster doses might be needed and what might warrant updating the makeup of vaccines to target specific coronavirus variants.

No official vote is planned, and there will be no discussion of authorization or approval for any specific products.

“As we prepare for future needs to address COVID-19, prevention in the form of vaccines remains our best defense against the disease and any potentially severe consequences,” Dr. Peter Marks, director of the FDA’s Center for Biologics Evaluation and Research, said in a news release Monday.

“Now is the time to discuss the need for future boosters as we aim to move forward safely, with COVID-19 becoming a virus like others such as influenza that we prepare for, protect against, and treat,” Marks said. “Bringing together our panel of expert scientific external advisors in an open, transparent discussion about booster vaccination is an important step to gain insight, input and expert advice as we begin to formulate the best regulatory strategy to address COVID-19 and virus variants going forward.”

‘It’s heading towards this vaccine becoming an annual vaccine’

The day before the FDA announced the meeting date, former FDA Commissioner Dr. Scott Gottlieb said he also thinks Covid-19 vaccines may become an annual shot.

“I think it’s heading towards this vaccine becoming an annual vaccine, at least for the foreseeable future, until we really understand the epidemiology of this disease and understand whether this coronavirus starts to recede into the background like the four circulating strains of the coronavirus that we’ve become accustomed to have,” Gottlieb, a Pfizer board member, told Margaret Brennan on CBS “Face the Nation” on Sunday.

Coronaviruses that are known to infect humans were first identified in the 1960s, and among them are four circulating strains that cause common colds. The other human coronaviruses are Middle East respiratory syndrome, or MERS; severe acute respiratory syndrome, or SARS; and SARS-CoV-2, the virus that causes Covid-19.

When it comes to Covid-19, “I think this is really a six-month vaccine in terms of providing really meaningful protection against symptomatic disease and infection,” Gottlieb said. “And this is likely to become an annualized vaccine for the majority of Americans.”

It remains clear that the coronavirus that causes Covid-19 is not disappearing any time soon. Rather, some researchers say we can expect the pandemic to transition into an endemic phase. Endemic means a disease has a constant presence in a population but is not affecting an alarmingly large number of people, as typically seen in a pandemic.

So SARS-CoV-2 could still circulate, but hopefully it would be at low enough levels that it no longer overwhelms our health systems.

“In terms of the virus itself, what we can expect is that it’s not going to go away, that we will have recurrent surges and that our immunity will wane over time,” said Dr. Abraar Karan, an infectious disease fellow at Stanford University.

Several studies have shown that the immunity against Covid-19 elicited by the Pfizer/BioNTech, Moderna and Johnson & Johnson vaccines can wane over several months, especially among older adults who might have weaker immune systems.

“So the combination of our immunity waning and then the virus mutating means that future surges are unpredictable,” Karan said.

“We will need boosters again in the future – probably later this year is my guess – and they will need to be tweaked more closely to what the most recent strain is that’s spreading,” he said. “We do this, obviously, annually for flu. … But flu has a more predictable seasonality to it.”

What a future booster might look like

Future Covid-19 boosters might be completely different formulas from the vaccines that are administered now.

Some companies, including Pfizer and Moderna, are developing variant-specific vaccines that could target whatever variant of the SARS-CoV-2 virus is circulating when the booster might be needed.

Pfizer and Moderna have said they are working on a vaccine that would specifically protect against the Omicron variant, even though it’s not clear whether one is needed.

Pfizer CEO Albert Bourla said the company is also hoping to make a vaccine that will protect against Omicron as well as all other variants of SARS-CoV-2.

The goal is to create “something that can protect for at least a year,” Bourla told CBS this month. “And if we are able to achieve that, then I think it is very easy to follow and remember so that we can go back to really the way [we] used to live.”

Moderna and the biotechnology company Novavax also are working on two-in-one combination vaccines that can offer protection against both flu and Covid-19.

“Our goal is to be able to have a single annual booster – so that we don’t have compliance issues where people don’t want to get two to three shots a winter, but they get one dose where they get a booster for corona and they get a booster for flu and RSV, to make sure that people get their vaccines,” Moderna CEO Stéphane Bancel said at the World Economic Forum in January of a single vaccine for Covid-19, influenza and respiratory syncytial virus, a common virus that causes cold-like symptoms.

There could be a benefit to having a combination Covid-19 and flu vaccine, Chatterjee said.

“There are logistical benefits: The number of injections that need to be given is reduced; the benefits to the storage facilities that are delivering, administering these vaccines don’t have to store as many vaccines because they’re in a combined form,” she said.

But she added that there are some limitations, as well.

“There are a couple of different issues with combinations. You have to make sure that they work together, which doesn’t always happen. Sometimes, the vaccine components can interfere with each other, and you don’t get as good an immune response as you would like,” Chatterjee said. “And then there’s the safety factor. As you add more vaccines together, often you get more reactions, particularly local reactions.”

Another element: Will enough people even take the vaccine?

The pace of Covid-19 booster administration in the United States has slowed. Although more than 65% of the US population is fully vaccinated with at least their initial series, only 29% of the population has received a third dose.

The uptake of flu shots in the United States also has room for improvement.

Traditionally, about half of adults get their flu shots. During the 2020-21 flu season, among adults 18 an older, coverage was 50.2%, according to CDC data.

Chatterjee said a combination flu and Covid-19 vaccine might improve that uptake.

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“I would assume – and this is an assumption on my part – that those who currently get the influenza vaccine would probably continue to get them, and if they were offered as combinations, most of them would probably take the combination vaccine,” Chatterjee said.

“And then for those who received the Covid vaccine, perhaps they will be encouraged to take the combination also, so that they get double protection against flu,” she added. “Am I optimistic? I am that we will get better coverage for both types of viruses through combination vaccine.”