Booster shots are here, after much hoopla from the White House and a great deal of discussion and consideration from the teams of doctors and other experts who advise the U.S. Food and Drug Administration and the U.S. Centers for Disease Control and Prevention.

More than 2 million people have already received third doses of Pfizer's coronavirus vaccine, but these technically were not booster shots — they were extra doses given to people whose immune systems are compromised and may not have responded fully to the first two doses of vaccines.

But now the CDC and FDA have agreed many Americans need boosters and should start getting them. Here are some important things to know about them:

Who is eligible?

Many adults will be eligible for boosters if they have already received two doses of Pfizer's vaccine.

"Starting today, if you are six months out from your last dose of the Pfizer vaccine, you are eligible for a booster if you fall into one of three high risk groups," U.S. Surgeon General Dr. Vivek Murthy told a White House COVID-19 briefing Friday.

"Number one: You are 65 or older. Number two: You have a medical condition that puts you at high risk of severe illness with COVID and these conditions include obesity, diabetes, high blood pressure, chronic kidney disease and others. And Number three: You work or live in a setting where you are at high risk of exposure to COVID. This includes health care workers, teachers, those living in shelters or prisons and grocery store workers."

The federal government website at vaccines.gov has links to pages outlining who is eligible for a booster shot and has lists of locations where shots are available.

The CDC's Dr. Kathleen Dooling told the Advisory Committee on Immunization Practices earlier this week there is a wide variety of people who might be included in the high risk groups. "Fully vaccinated persons with underlying medical conditions may be at risk of severe COVID-19 if they become infected with SARS-CoV-2," she said. They include cancer, stroke, chronic kidney disease, chronic obstructive pulmonary disease or COPD, diabetes, heart conditions, obesity, pregnancy and smoking.

White House COVID-19 coordinator Jeff Zients said up to 20 million Americans fall into these categories as of now.

When and where can people get one?

People have already started getting booster shots.

Zients said there is plenty of supply, and people should be able to get boosters at pharmacies, doctors' offices and sometimes at mass vaccination sites.

"Boosters will be free for everyone, regardless of immigration or health insurance status. No ID or insurance required," he said Friday.

"And we've worked closely with partners including governors, pharmacies, doctors, long term care facilities and other providers so that eligible Americans are able to get a booster shot at roughly 80,000 places across the country, including over 40,000 local pharmacies," Zients added.

"CDC contacted tens of thousands of nursing homes, assisted living facilities, and other high-risk settings to ensure that they are ready," he said.

"Colorado has nine mobile vaccination clinics ready to go to get boosters to where people are. And we'll double that number to 18 over the coming weeks."

He said Colorado, New York, Ohio and other states were readying large vaccination centers if there is demand.

What about everyone else—including people who got Moderna or Johnson & Johnson vaccines?

The FDA and CDC will continue to consider widening the recommendations for who should and could get booster shots. Moderna has asked the FDA to consider booster doses for people who got its vaccine. Johnson & Johnson has yet to apply.

CDC Director Dr. Rochelle Walensky said her agency acted quickly on FDA recommendations for Pfizer vaccine recipients.

"We will, with similar urgency, evaluate the available data in the coming weeks to swiftly make additional recommendations for other populations at risk, and people who received the Moderna and J&J vaccines," she told Friday's briefing.

Murthy made a similar promise.

"I want to speak directly to those who received Moderna and J&J," Murthy told the briefing.

"Your health matters just as much as other vaccine recipients, and we want to make sure that your protection against COVID is strong and reliable as well. That's why the FDA is working with Moderna and J&J to get and process their data as quickly as possible with the goal of making booster recommendations for Moderna and J&J recipients in the coming weeks. This is a high, high priority."

Why do people need them?

The protection provided by COVID-19 vaccines appears to wane over time, especially for people 65 and older, the CDC's Ruth Link-Gelles, who helps lead the CDC's Vaccine Effectiveness Team, said Friday.

She reviewed a series of studies looking at the overall effectiveness of vaccines in various groups between February and August and found similar patterns for Pfizer's and Moderna's vaccines, both made using mRNA. Effectiveness started to wane a few months after people were fully vaccinated — defined as two weeks after their second dose of either vaccine.

"For individuals 65 plus, we saw significant declines in VE [vaccine effectiveness] against infection during Delta for the mRNA products," Link-Gelles told CDC vaccine advisers this past week.

"We also saw declines, particularly for Pfizer, for 65 up, that we're not seeing in younger populations. Finally there's evidence of waning VE against hospitalization in the Delta period," she said.

In a study of 4,000 healthcare personnel, first responders, and other frontline workers in eight places who were tested every week regardless of symptoms, vaccine protection against any infection declined from 91% pre-Delta to 66% during Delta.

A study called IVY looked at hospitalized adults in 18 states between March and August. Efficacy of Pfizer's vaccine waned from 91%, 14 to 120 days after full vaccination, to 77% three months or more after full vaccination. Moderna's vaccine effectiveness did not really wane, staying at 92% or 93% in that study.

Pfizer says its studies show booster doses bring people's immunity back up to what it was right after they got their second shots, or to even higher levels.

Do I need a doctor's note?

No. People are being asked to "self-attest" as to their eligibility for a booster vaccine.

But people should not cheat — especially when it comes to waiting six months or so before getting a booster, said Dr. Anthony Fauci, Director of the National Institute of Allergy and Infectious Diseases.

That's because a longer time period between prime — the first doses of vaccine — and boost helps the immune system mature. The longer one waits, the better the immune response.

"If you allow the immune response to mature over a period of a few months, you get much more of a bang out of the shot, as it were — an enhancement of your antibodies," he said.

MASON, Ohio —

Whether singing to a crowd or jammin' at home, 9-year-old JJ Day was an entertainer.

"Whenever we had our friends over, he would always play along with us. He would always be making poses for the camera. He would always make us laugh," his sister, Morgan Day said.

JJ's older sister, Madison said, "Potty humor, that was his favorite. He made jokes constantly ... He told me a few of his new year's resolutions, and one was to have more friends."

The Mason third-grader, who wanted to be Mickey Mouse at Disney World one day, knew how to dominate a room.

"His personality, it was explosive. It was so big," said his mother, Kristen Day. "He was our source of huge laughter."

JJ's presence was always filled with love.

"He made sure that each of us knew that he loved us, and we loved him," Kristen Day said.

JJ Day unexpectedly last Saturday. While his family still doesn't have answers about how he died, their focus is on how he lived. The term "Love like JJ" has spread through the community and on social media.

"I mean, he's everywhere," said his father, Jon Day. "He would want to be everywhere. He would want to be in everyone's face."

Stories of JJ can fill a room with laughter, but words can't describe the pain in his family's hearts.

The Days said they've found strength in their community and every person who has reached out to say they will try and love like JJ.

"We hear you. We see you and we feel you," Jon Day said.

"We feel the prayers. We feel the support. We absolutely feel it. I know my girls feel it too," Kristen Day said.

The Days said they believe JJ was destined to change the world, and now, they will help him do so.

A foundation, https://www.lovelikejj.org/ has been set up in his name.

Services for JJ will be held Saturday. More information can be found here:

https://www.muellerfunerals.com/obituary/jonathan-day?fbclid=IwAR3O4pWvceUTktN_0LfqJCr09vS9WeibptxuOQuief0fb4DtfrQdfWyKdbw

Johnson & Johnson said Wednesday that new data from early trials of a booster shot of its COVID-19 vaccine provides a "rapid and robust increase in spike-binding antibodies" that fight off the virus.

In a press release, the company noted that the antibody response provided by the single-shot vaccine was "strong and stable" eight months later. However, eyes are turning to booster shots as widespread vaccine use nears the one-year mark.

In its press release, Johnson & Johnson noted that a person who gets a booster shot saw a nine-fold increase in antibodies when compared to antibody response 28 days after an initial dose.

"With these new data, we also see that a booster dose of the Johnson & Johnson COVID-19 vaccine further increases antibody responses among study participants who had previously received our vaccine," said Dr. Mathai Mammen, the global head of Janssen Research & Development, Johnson & Johnson. "We look forward to discussing with public health officials a potential strategy for our Johnson & Johnson COVID-19 vaccine, boosting eight months or longer after the primary single-dose vaccination."

Earlier this month, top federal health officials recommended that Americans seek out a COVID-19 booster shot eight months after full vaccination. The booster shot program is slated to begin Sept. 20, pending approval from the Food & Drug Administration and the Centers for Disease Control and Prevention.

In issuing a recommendation for booster shots, officials said that while all COVID-19 vaccines remain extremely effective in preventing instances of severe infection or death from the virus, there has been some data to show that those vaccinated are more susceptible to mild cases of the virus eight months after vaccination. They've also seen evidence that those vaccinated are more susceptible to unknowingly spreading the virus as time goes on.

The Johnson & Johnson vaccine was granted emergency use authorization in late February, meaning booster shots for those who received the J&J vaccine would be available in late October if the FDA and the CDC ultimately approve them.

The Johnson & Johnson vaccine still only has emergency use approval from the FDA. Earlier this week, the agency granted full approval to the Pfizer vaccine — the first COVID-19 vaccine to receive such a designation.

Related video above: The Psychology Behind Vaccine Hesitancy

Do I need a booster if I got the Johnson & Johnson vaccine?

Probably at some point, but health officials still are collecting the data needed to decide.

With boosters being planned in the U.S. as early as the fall for those who got the two-shot Pfizer and Moderna vaccines, recipients of the single-dose J&J jab might be wondering just how well their protection is holding up.

All the vaccines used in the U.S. — including the J&J vaccine — still are doing their job of preventing hospitalizations and deaths from COVID-19.

"I don't think there's any signal that the J&J vaccine is failing at its primary task," said Dr. Amesh Adalja, an infectious disease specialist at the Johns Hopkins Bloomberg School of Public Health.

Despite continued protection against severe disease, U.S. officials are planning to offer Pfizer and Moderna boosters eight months after the second shot based on evidence that effectiveness against infection wanes over time. Adding to the decision, the vaccines don't appear quite as strong against the highly contagious delta variant as they were against earlier versions of the virus.

U.S. Surgeon General Vivek Murthy said boosters "will likely be needed" for the J&J vaccine. Authorities expect more data to decide in the coming weeks.

That's in part because the J&J rollout didn't start until March, several months after Pfizer and Moderna vaccinations began. The J&J shot is made differently. And there's more data about how the Pfizer and Moderna vaccines fare against delta because they're more widely used in countries where the variant struck before its U.S. surge.

There is some real-world data showing J&J's shot holds up against the delta variant. A huge study of health workers in South Africa showed the vaccine remains highly effective against hospitalizations and death from the variant. And the vast majority of so-called "breakthrough" infections in vaccinated people were mild.

J&J has also presented lab data on virus-fighting antibodies that indicates its vaccine protects against the delta variant for eight months and counting. Another small lab study has raised questions about whether a two-dose approach would work better, an option J&J is studying.

A separate issue is whether people with severely weakened immune systems should get extra shots as part of their original vaccinations, since they don't respond as well to any vaccines. The government now recommends a third shot of the Pfizer or Moderna vaccines for organ transplant recipients and others in this group. But it's still collecting data before making a similar recommendation for another dose of the J&J vaccine.

CNN —

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."

The U.S. Food and Drug Administration has authorized the use of the Johnson & Johnson coronavirus vaccine in adults.

Maureen Ferran, a virologist at the Rochester Institute of Technology, explains how this third authorized vaccine works and explores the differences between it and the Moderna and Pfizer–BioNTech vaccines that are already in use.

1. How does the Johnson & Johnson vaccine work?

The Johnson & Johnson vaccine is what's called a viral vector vaccine.

To create this vaccine, the Johnson & Johnson team took a harmless adenovirus – the viral vector – and replaced a small piece of its genetic instructions with coronavirus genes for the SARS-CoV-2 spike protein.

After this modified adenovirus is injected into someone's arm, it enters the person's cells. The cells then read the genetic instructions needed to make the spike protein and the vaccinated cells make and present the spike protein on their own surface. The person's immune system then notices these foreign proteins and makes antibodies against them that will protect the person if they are ever exposed to SARS-CoV-2 in the future.

The adenovirus vector vaccine is safe because the adenovirus can't replicate in human cells or cause disease, and the SARS-CoV-2 spike protein can't cause COVID–19 without the rest of the coronavirus.

This approach is not new. Johnson & Johnson used a similar method to make its Ebola vaccine, and the AstraZeneca-Oxford COVID-19 vaccine is also an adenovirus viral vector vaccine.

2. How effective is it?

The FDA's analysis found that, in the U.S., the Johnson & Johnson COVID-19 vaccine was 72% effective at preventing all COVID-19 and 86% effective at preventing severe cases of the disease. While there is still a chance a vaccinated person could get sick, this suggests they would be much less likely to need hospitalization or to die from COVID-19.

A similar trial in South Africa, where a new, more contagious variant is dominant, produced similar results. Researchers found the Johnson & Johnson vaccine to be slightly less effective at preventing all illness there – 64% overall – but was still 82% effective at preventing severe disease. The FDA report also indicates that the vaccine protects against other variants from Britain and Brazil too.

3. How is it different from other vaccines?

The most basic difference is that the Johnson & Johnson vaccine is an adenovirus vector vaccine, while the Moderna and Pfizer vaccines are both mRNA vaccines. Messenger RNA vaccines use genetic instructions from the coronavirus to tell a person's cells to make the spike protein, but these don't use another virus as a vector. There are many practical differences, too.

Both of the mRNA-based vaccines require two shots. The Johnson & Johnson vaccine requires only a single dose. This is key when vaccines are in short supply.

The Johnson & Johnson vaccine can also be stored at much warmer temperatures than the mRNA vaccines. The mRNA vaccines must be shipped and stored at below–freezing or subzero temperatures and require a complicated cold chain to safely distribute them. The Johnson & Johnson vaccine can be stored for at least three months in a regular refrigerator, making it much easier to use and distribute.

As for efficacy, it is difficult to directly compare the Johnson & Johnson vaccine with the mRNA vaccines due to differences in how the clinical trials were designed. While the Moderna and Pfizer vaccines are reported to be approximately 95% effective at preventing illness from COVID–19, the trials were done over the summer and fall of 2020, before newer more contagious variants were circulating widely. The Moderna and Pfizer vaccines might not be as effective against the new variants, and Johnson & Johnson trials were done more recently and take into account the vaccine's efficacy against these new variants.

4. Should I choose one vaccine over another?

Although the overall efficacy of the Moderna and Pfizer vaccines is higher than the Johnson & Johnson vaccine, you should not wait until you have your choice of vaccine – which is likely a long way off anyway. The Johnson & Johnson vaccine is nearly as good as the mRNA-based vaccines at preventing serious disease, and that's what really matters.

The Johnson & Johnson vaccine and other viral-vector vaccines like the one from AstraZeneca are particularly important for the global vaccination effort. From a public health perspective, it's important to have multiple COVID-19 vaccines, and the Johnson & Johnson vaccine is a very welcome addition to the vaccine arsenal. It doesn't require a freezer, making it much easier to ship and store. It's a one-shot vaccine, making logistics much easier compared with organizing two doses per person.

As many people as possible need to be vaccinated as quickly as possible to limit the development of new coronavirus variants. Johnson & Johnson is expected to ship out nearly four million doses as soon as the FDA grants emergency use authorization. Having a third authorized vaccine in the U.S. will be a big step towards meeting vaccination demand and stopping this pandemic.

This article is republished from The Conversation under a Creative Commons license. Read the original article here.