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Covid-19 omicron pictures out there, however their effectiveness is unclear

Covid-19 omicron shots available, but their effectiveness is unclear

The US this week approved the first major revision of Covid-19 vaccines in a bid to stem an expected spate of infections and hospitalizations this fall.

However, it is unclear how much protection the new booster shots will offer. The Food and Drug Administration and the Centers for Disease Control and Prevention have cleared the footage without data from clinical trials testing the newly formulated doses in humans.

The new boosters, approved for people 12 and older, target the highly contagious and immune-avoidable subvariant omicron BA.5, which sparked a surge in breakthrough infections over the summer. The shots also targeted the original strain of the virus, which first emerged in Wuhan, China, in 2019.

The country’s top health authorities acted urgently this summer to ensure the new boosters are rolled out in time for the fall. They are concerned that the declining effectiveness of legacy vaccines creates an opportunity for omicron to trigger another wave of hospitalizations this winter as people spend more time indoors, where the airborne virus spreads more easily.

According to CDC epidemiologist Heather Scobie, deaths and hospitalizations among the elderly, the most commonly vaccinated age group in America, have risen since April as Omicron continues to mutate into more transmissible subvariants that evade the protection of the original vaccines.

dr Peter Marks, who heads the FDA’s office that reviews vaccines, said the new boosters aim to restore the high level of protection vaccines showed in early 2021. However, Marks acknowledged that federal government experts just don’t know yet whether the boosters will meet the high bar that these doses set.

“We don’t yet know exactly if we’ll reach the same level, but that’s the goal here. And we think the evidence we’ve seen suggests that,” Marks told reporters during a news conference following the FDA approval Wednesday.

The FDA will be monitoring to see if the boosters are meeting that goal, Marks said. When Pfizer and Moderna’s syringes were approved in December 2020, they offered more than 90 percent protection in preventing Covid.

Marks told reporters it will likely be at least a few more months before human data on the BA.5 boosters is available to the public. But he said the FDA used essentially the same process to authorize the new boosters it’s relied on for years to switch virus strains in flu shots.

“We’re pretty confident that what we have is very similar to the situation that we’ve done in the past with influenza mutations where we’re not conducting clinical trials for them in the United States,” Marks said. “We know from how the vaccine works and from the data we have that we can predict how well the vaccine will work.”

The new boosters could prevent 2.4 million infections, 137,000 hospitalizations and 9,700 deaths if no new variant emerges, according to a forecast by a team of scientists predicting the course of the pandemic, called the Covid-19 Scenario Modeling Hub.

However, according to the scientists, this forecast is based on optimistic assumptions about the coverage and effectiveness of boosters. The model assumes that vaccines will prove 80% effective in preventing disease and the public will largely embrace the new boosters. There is no efficacy data on the new shots and it is unclear how strong the public demand for them will be.

The CDC estimates that an early fall immunization campaign with booster shots could save the United States between $63 billion and $109 billion in medical costs by preventing hospitalizations and ICU admissions.

Pfizer and Moderna originally developed new boosters to target the first version of Omicron, BA.1, which caused the massive wave of infections and hospitalizations last winter. But keeping up with the rapid evolution of the virus has proven to be a challenge.

By the time the country’s top health leaders began providing new boosters in earnest in April, more transmissible subvariants had already pushed omicron BA.1 out of circulation. In June, the FDA urged vaccine makers to shift gears and target Omicron BA.5 after it rose to dominance.

That decision didn’t leave Pfizer and Moderna enough time to complete human clinical trials of the new boosters before a fall launch of the vaccine.

As a result, the FDA and CDC rely on human data from the clinical trials of the BA.1 syringes to understand how the BA.5 boosters might work. They also relied on data from studies testing the BA.5 boosters in mice.

The CDC’s Independent Advisory Committee supported the shooting Thursday in an overwhelming vote.

However, some members of the panel also had concerns about the lack of human data.

“I’m really struggling with a vaccine that doesn’t have clinical data that’s reported for people, for those who would actually get the vaccine,” said Dr. Oliver Brooks, a committee member and chief medical officer at Watts HealthCare Corp. in Los Engel.

dr Pablo Sanchez, the only member of the CDC committee who voted against the injections, called the decision to recommend the new boosters without human data premature.

“There’s already a lot of hesitation with vaccines — we need the human data,” said Sanchez, a professor of pediatrics at Ohio State University.

dr Doran Fink, deputy chief of the FDA’s Division of Vaccine Review, told the hesitant committee members that the new booster shots use the exact same manufacturing process as the old vaccines and contain the same total amount of mRNA, the code that instructs human cells to produce the proteins that evoke an immune response to fight off Covid.

Fink said the BA.1 and the BA.5 recordings are similar enough to use data from the BA.1 human trials to get a good idea of ​​how the new BA.5 boosters work will work.

Pfizer and Moderna presented data at the CDC meeting showing that the BA.1 vaccines elicited a stronger immune response in humans than the old vaccines. The mouse studies by both companies on the BA.5 syringes also showed a stronger immune response.

CDC Director Dr. Rochelle Walensky said last week that a longer wait for human data from the BA.5 shots could mean the boosters are out of date by the time a new variant emerges.

“It’s always about too slow versus too fast,” Walensky told Conversations on Health Care in a radio interview. “One of the challenges is when we wait for that data to show up in human data… we’re going to be using what I think might be an outdated vaccine.”

Moderna completed recruitment for its clinical trials last week and expects results by the end of the year. Pfizer’s clinical trials are ongoing, although the company hasn’t given a timeline for when it will have data.

Brooks questioned why the FDA chose a BA.5 vaccine when clinical data is available for the BA.1 vaccines that vaccine manufacturers originally developed. Canada and the UK have approved new booster shots targeting omicron BA.1

Fink said the US approved BA.5 based on advice from the FDA’s independent committee, data from South Africa indicating that natural infection by the subvariant provides broader protection than infection by BA.1, and the fact that BA.5 is dominant.

Although committee members were somewhat reluctant to proceed without the human data, they agreed that the new boosters should have a similar safety profile to the old vaccines, as they use the same platform. The Covid vaccines have been given to millions of people in the US with mostly mild side effects.

According to the FDA, the most common side effects from the human trials of BA.1 syringes were pain, redness, swelling at the injection site, fatigue, headache, muscle pain, joint pain, chills, nausea, vomiting, and fever.

dr Sara Oliver, a CDC official, told the committee that the risk of myocarditis, an inflammation of the heart muscle, after a BA.5 booster is unknown. However, health authorities believe it will be similar to the risk seen with the old vaccines.

The Pfizer and Moderna vaccines have been associated with an increased risk of myocarditis in young men and adolescent boys, mainly after the second dose. However, according to the CDC, the risk of myocarditis is higher from Covid infection than from vaccination.

dr Grace Lee, the chair of the CDC committee, tried to reassure the public that there is a robust monitoring system to monitor safety and that the panel will meet again if new concerns arise.

“I just want to make sure members of the public know we’re continuing to monitor closely,” Lee said. “We have systems and teams that continue to monitor and meet.”

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Vaccine Effectiveness In opposition to An infection Might Wane, C.D.C. Research Discover

Vaccine Effectiveness Against Infection May Wane, C.D.C. Studies Find

The Centers for Disease Control and Prevention published three studies on Wednesday that federal officials said provided evidence that booster shots of the Pfizer BioNTech and Moderna coronavirus vaccines would be needed in the coming months.

However, some experts said the new research did not support the decision to recommend a booster dose to all Americans.

Taken together, the studies show that while the vaccines are still highly effective against hospital admissions and deaths, their bulwark against infection with the virus has weakened in recent months.

The finding is consistent with early data from seven states compiled this week by the New York Times, suggesting an increase in breakthrough infections and a smaller increase in hospital admissions among vaccinated people as the Delta variant spread in July.

The decline in effectiveness against infections may be due to declining vaccine immunity, failure of precautionary measures like wearing masks, or the rise of the highly contagious Delta variant, experts said – or a combination of all three.

“We are concerned that this pattern of decline that we are seeing will continue in the coming months, which could result in decreased protection from serious illness, hospitalization and death,” said Dr. Vivek Murthy, the surgeon general, at a press conference at the White House on Wednesday.

Citing the data, federal health officials outlined a plan for Americans who received the two vaccines to receive a booster dose eight months after receiving their second dose starting September 20.

People who have received the Johnson & Johnson vaccine may also need additional doses. That vaccine wasn’t launched until March 2021, however, and a plan to deploy boosters will be drawn up after reviewing new data expected over the next few weeks, officials said.

Some scholars were skeptical of the government’s new initiative.

“These data support the administration of additional doses of the vaccine to severely immunocompromised individuals and nursing home residents, not the general public,” said Dr. Celine Gounder, Infectious Disease Specialist at Bellevue Hospital Center and former advisor to the administration for the pandemic.

Boosters would only be justified if the vaccines didn’t prevent hospital stays with Covid-19, she said.

“Feeling sick like a dog and staying in bed but not lying in hospital with severe Covid is not reason enough,” said Dr. Gounder. “We will be better protected by vaccinating the unvaccinated here and around the world.”

It’s unclear whether a third dose would help people who didn’t evoke a robust immune response to the first two doses, said Bill Hanage, an epidemiologist at Harvard TH Chan School of Public Health.

And the recommendation for boosters could also undermine confidence in the vaccines, he warned: “A third shot will increase skepticism among people who have not yet received a dose that the vaccines will help them.”

Taken together, the new studies show overall that vaccines are about 55 percent effective against all infections, 80 percent against symptomatic infections, and 90 percent or more against hospitalization, noted Ellie Murray, an epidemiologist at Boston University.

“These numbers are actually very good,” said Dr. Murray. “The only group for which this data would suggest boosters for me are the immunocompromised.”

Updated

Aug. 19, 2021, 10:57 a.m. ET

The apparent decrease in the vaccine’s effectiveness against infection could instead have been caused by increased exposure to the highly contagious Delta variant during a period of unrestrained social interaction, she added: “This seems like a real possibility to me, given many early vaccines motivated were the desire to see friends and family and return to normal. “

Dr. Murray said a booster vaccination would undoubtedly boost a person’s immunity, but the added benefit can be minimal – and just as easily achieved by wearing a mask or avoiding indoor dining and crowded bars.

The government’s focus on vaccines has undermined the importance of building other precautions into people’s lives in a convenient and sustainable way and strengthening testing capacity, said Dr. Murray and other experts.

“This is one of the reasons I think the government’s focus on vaccines is so damaging to morality,” she added. “We probably won’t get back to normal anytime soon.”

Before people can start the booster, the Food and Drug Administration must first authorize a third dose of the vaccines manufactured by Pfizer-BioNTech and Moderna, and an advisory committee from the CDC must review the evidence and make recommendations.

One of the new CDC studies analyzed the effectiveness of vaccines in residents of nearly 4,000 nursing homes from March 1 to May 9 before the advent of the Delta variant and of nearly 15,000 nursing homes from June 21 to August 1 as the new infections variant dominated in the country.

The effectiveness of the vaccines in preventing infection dropped from about 75 percent to 53 percent between those dates, the study found. The protection of the vaccines against serious illness has not been assessed.

Understand the state of vaccination and masking requirements in the United States

    • Mask rules. The Centers for Disease Control and Prevention in July recommended that all Americans, regardless of vaccination status, wear masks in public places indoors in areas with outbreaks, reversing the guidelines offered in May. See where the CDC guidelines would apply and where states have implemented their own mask guidelines. The battle over masks is controversial in some states, with some local leaders defying state bans.
    • Vaccination regulations. . . and B.Factories. Private companies are increasingly demanding corona vaccines for employees with different approaches. Such mandates are legally permissible and have been confirmed in legal challenges.
    • College and Universities. More than 400 colleges and universities require a vaccination against Covid-19. Almost all of them are in states that voted for President Biden.
    • schools. On August 11, California announced that teachers and staff at both public and private schools would have to get vaccinated or have regular tests, the first state in the nation to do so. A survey published in August found that many American parents of school-age children are against mandatory vaccines for students, but are more supportive of masking requirements for students, teachers and staff who do not have a vaccination.
    • Hospitals and medical centers. Many hospitals and large health systems require their employees to receive a Covid-19 vaccine, due to rising case numbers due to the Delta variant and persistently low vaccination rates in their communities, even within their workforce.
    • new York. On August 3, New York City Mayor Bill de Blasio announced that workers and customers will be required to provide proof of vaccination when dining indoors, gyms, performances, and other indoor situations. City hospital staff must also be vaccinated or have weekly tests. Similar rules apply to employees in New York State.
    • At the federal level. The Pentagon announced that it would make coronavirus vaccinations compulsory for the country’s 1.3 million active soldiers “by mid-September at the latest. President Biden announced that all civil federal employees would need to be vaccinated against the coronavirus or undergo regular tests, social distancing, mask requirements and travel restrictions.

Nursing homes did not have to report the number of residents vaccinated until after June 6, which “makes comparisons over time very difficult,” said Dr. Murray. “It is entirely possible that the effectiveness of the vaccine reported here has not really diminished over time.”

The decline in effectiveness could also be due to the spread of the Delta variant, said Dr. Gounder.

“It makes sense to give vaccinated nursing home residents an extra dose of vaccine, but what will have an even bigger impact on protecting these nursing home residents is vaccinating their caregivers,” she said. Many caregivers in long-term care facilities remain unvaccinated.

A second study evaluated data from New York State from May 3 to July 25, when the Delta variant grew to more than 80 percent of new cases. The effectiveness of vaccines in preventing cases in adults fell from 91.7 percent to 79.8 percent during that time, the study found. But the vaccines remained just as effective at preventing hospital stays.

In those weeks, New York recorded 9,675 breakthrough infections – about 20 percent of the state’s total cases – and 1,271 hospital admissions of vaccinated people, accounting for 15 percent of all Covid-19 hospital admissions.

Although fully immunized people of all ages contracted the virus, the vaccine’s effectiveness fell the most, from 90.6 percent to 74.6 percent in people ages 18 to 49 – who are often the least likely to take precautions and are most likely to socialize .

Data from Israel suggests immunity to infection has declined in vaccinated adults aged 65 and over. But in the New York data, the effectiveness of the vaccines in this group hardly diminished.

Adults aged 65 and over were hospitalized more often than other age groups, regardless of their vaccination status. But the vaccines did not show a decrease in effectiveness against hospital admissions in any of the age groups.

The CDC’s third study found the vaccines showed 90 percent effectiveness against hospital stays in the country, “which is excellent,” noted Dr. Gounder.

The vaccines provided less protection against hospitalization in immunocompromised people. “But not all immunocompromised people will respond to an extra dose of vaccine,” noted Dr. Gounder.

To protect these vulnerable people, everyone around them should be vaccinated and continue to wear masks, she added.

The vaccines appear to be less effective than the studies that led to their approval, as those studies were done before the delta variant emerged.

Statistically, as more unvaccinated people become infected, recover, and gain natural immunity, the vaccines may lose relative effectiveness. And scientists always expected that the proportion of those who were vaccinated among those infected would increase if more people were vaccinated.

If preventing infection is the goal, it would be smarter to develop a booster shot of a nasal spray vaccine that will create better immunity in the nose and throat where the virus enters the body, said Dr. Gounder.

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Israeli Knowledge Suggests Potential Waning in Effectiveness of Pfizer Vaccine

Israeli Data Suggests Possible Waning in Effectiveness of Pfizer Vaccine

As Israel struggles with a new surge of coronavirus cases, its health ministry reported on Thursday that although effectiveness of the Pfizer-BioNTech vaccine remains high against severe illness, its protection against infection by the coronavirus may have diminished significantly compared with this winter and early spring.

Analyzing the government’s national health statistics, researchers estimated that the Pfizer shot was just 39 percent effective against preventing infection in the country in late June and early July, compared with 95 percent from January to early April. In both time periods, however, the shot was more than 90 percent effective in preventing severe disease.

Israeli scientists cautioned that the new study is much smaller than the first and that it measured cases in a narrower window of time. As a result, a much larger range of uncertainties flank their estimates, which could also be skewed by a variety of other factors.

Dr. Ran Balicer, the chairman of Israel’s Covid-19 National Expert Advisory Panel, said that the challenges of making accurate estimates of vaccine effectiveness were “immense.” He said that more careful analysis of the raw data was needed to understand what is going on.

“I think that data should be taken very cautiously because of small numbers,” said Eran Segal, a biologist at the Weizmann Institute of Science who is a consultant to the Israeli government on vaccines.

Nevertheless, the new estimates are raising concern both in Israel and elsewhere, including the United States, that the vaccine might be losing some of its effectiveness. Possible reasons include the rise of the highly contagious Delta variant or a waning of protection from the shots over time.

Israel launched an aggressive campaign with the Pfizer vaccine in January, and the country has achieved one of the highest vaccination rates in the world, with 58 percent of the population fully vaccinated. At the start of the campaign, government researchers began estimating how much the shot reduced people’s risk of getting Covid-19.

They published their results in May, based on records from Jan. 24 to April 3: They estimated that the vaccine was 95 percent effective in preventing infection from the coronavirus in the country. In other words, the risk of getting Covid-19 was nearly 100 percent reduced in vaccinated people compared to unvaccinated ones. The researchers also estimated that the vaccine was 97.5 percent effective against severe disease.

From a peak of over 8,600 cases a day in January, cases plummeted in the following months until only a few dozen people were testing positive on a daily basis across Israel. The vaccine most likely played a part in that drop, along with the tight restrictions that the government imposed on travel and meetings.

Israel began relaxing its restrictions in the spring. In late June, the cases surged again. Now, over a thousand people are testing positive each day, leading Israel to restore some restrictions this week.

Updated 

July 23, 2021, 2:47 p.m. ET

Some of the people that tested positive for the coronavirus in the new surge were fully vaccinated. Epidemiologists had expected such breakthrough infections, as they do with all vaccines.

Researchers at the Ministry of Health took another look at the effectiveness of the vaccine, limiting their analysis to the surge from June 6 to July 3. In that period, they estimated, the effectiveness of the vaccine at preventing infections was down to 64 percent.

More recently, they ran another analysis. This time, they looked at cases between June 20 and July 17. In that period, they estimated, the vaccine’s effectiveness was even lower: just 39 percent against infection.

Still, they estimated that the vaccine’s effectiveness against serious disease remained high, at 91.4 percent.

If a vaccine has an effectiveness of 39 percent that does not mean that 61 percent of people who got vaccinated were infected by the coronavirus. Instead, it means the risk of getting infected is 39 percent less among vaccinated people compared to unvaccinated. So even at that lower percentage, the data shows that vaccinated people have significantly less risk of getting infected than unvaccinated people.

The small number of people in the latest study means that the true effectiveness might be lower or higher. Making the numbers even more uncertain is the fact that the new surge has not yet spread evenly across the whole country. Travelers who have picked up the highly contagious Delta variant have brought it back to neighborhoods where vaccination rates are relatively high.

Understand the State of Vaccine Mandates in the U.S.

The new outbreaks have yet to swamp communities of Orthodox Jews or Arab Israelis, where vaccination rates are lower. That imbalance may make the vaccine seem less effective than it really is.

Also, the ages of people vaccinated vary significantly during the different time periods studied. For example, the people who got their vaccines in January were different than those who got them in April in one major respect: They were over 60. If more people who got vaccinated in January are now getting infected, it may not have to do with the vaccine itself, but with their advanced age — or some other factor that researchers have yet to take into consideration.

Still, the new estimates have prompted some researchers to ponder what might be happening to the vaccines. The Delta variant grew more common in Israel in June, raising the possibility that it might be good at evading the vaccine.

In Britain, where Delta began surging earlier in the year, researchers estimated the effectiveness of the Pfizer-BioNTech vaccine against the variant, based on a review of everyone in the United Kingdom who got vaccinated up till May 16. On Wednesday, they reported in the New England Journal of Medicine that it is 88 percent effective against symptomatic Covid-19.

Another possibility is that the Pfizer-BioNTech vaccine is gradually becoming less potent. The Ministry of Health researchers found that people who were inoculated in January were having breakthrough infections at a greater rate than people vaccinated in April.

If the vaccine is indeed waning after six months, the implications can be enormous. It can influence the Israeli government’s current deliberations about whether to give people a third shot. Dr. Segal says that if the vaccines are indeed losing some of their potency, then it might be wise to roll out boosters to fight the Delta-driven outbreak.

“If a third booster is safe and if it seems that it really would give a benefit, I think this is something we should definitely do as quickly as possible,” he said.

Dr. Balicer, who is also the chief innovation officer at Clalit Health Services, said that he and his colleagues are working on their own study on the effectiveness of the vaccine in Israel, using Clalit’s health care records to take into account such confounding factors.

“I think there is definitely some waning, but not as much as hypothesized based on the crude data, and it’s not just waning to blame,” Dr. Balicer said. “We are now trying to figure it out in a clean way.”