The current COVID-19 boosters targeting the Omicron XBB.1.5 subvariant are still offering solid protection against infection, hospitalizations, and death, but are somewhat limited in efficacy against illnesses caused by the JN.1 subvariant, now the dominant strain in the United States, according to a research letter yesterday in the New England Journal of Medicine.
Protection against infection 4 weeks after vaccination was 52%, and against COVID-related hospital illness it was 67%, but during the JN.1-dominant period it dropped to 44% and 60%, respectively.
The authors said the findings underscore the need for new boosters. Next week, the US Food and Drug Administration's VRBPAC (Vaccines and Related Biological Products Advisory Committee) will meet to select COVID and influenza strains to include in updated vaccines.
The elected strain will likely be the JN.1 subvariant.
"The relatively low effectiveness of the XBB.1.5 vaccines against the JN.1 subvariant, together with the waning effectiveness over time, underscores the need for new vaccines targeting the JN.1 strain," said first study author Dan-Yu Lin, PhD, in a press release from the University of North Carolina Gillings School of Public Health.
Lin and colleagues assessed the efficacy of the Moderna, Pfizer, and Novavax boosters from September 11, 2023, to February 21, 2024, in a cohort of approximately 1.8 million people captured in the Nebraska Electronic Disease Surveillance System and the Nebraska State Immunization Information System (NESIIS).
In total, 218,250 people in the cohort (11.9%) received XBB.1.5 vaccines, of whom 133,403 (61.1%) received the PfizerBioNTech vaccine and 84,307 (38.6%) received the Moderna vaccine, the authors said.
The researchers recorded a total of 21,988 SARS-CoV-2 infections, 1,364 COVID-19related hospitalizations, and 237 COVID-19related deaths in the cohort.
Efficacy peaked at 4 weeks
For all three booster vaccines targeting XBB.1.5, efficacy peaked at 1 month, with significant waning at 10 to 20 weeks.
At 4 weeks after vaccination, the XBB.1.5 vaccines were 52.2% effective at preventing infection (95% confidence interval [CI], 44.6% to 58.7%). Efficacy against infection dropped at 10 weeks to 2.6% (95% CI, 28.1% to 36.8%), and at 20 weeks to 20.4% (95% CI, 6.2% to 32.5%).
The boosters were 66.8% effective at preventing hospitalization at 4 weeks (95% CI, 51.7% to 77.1%), and decreased to 57.1% (95% CI, 40.4% to 69.2%) after 10 weeks.
"The effectiveness against death was higher than that against other end points; however, there remains substantial uncertainty owing to the small number of deaths," the authors said.
To assess how the booster performed against JN.1, the authors analyzed data comparing people who received the XBB.1.5 vaccines on or before October 25, 2023when JN.1. was first detected in Nebraskaand those who received them after October 25, 2023.
During that period, boosters provided 44.3% protection against infection at 4 weeks (95% CI, 33.5% to 53.4%) and 60.1% protection against hospitalization (95% CI, 30.9% to 77.0), which likewise waned over time.
"The vaccine effectiveness was lower in the second cohort than in the first cohort, which indicates that the XBB.1.5 vaccines were less protective against JN.1 than against XBB sublineages," the authors wrote.
It would be worthwhile to deploy new vaccines this fall that target the JN.1. strain.
"It would be worthwhile to deploy new vaccines this fall that target the JN.1. strain," Lin said in the release.
Spotmatik / iStock
COVID-19 accounted for much more absenteeism than influenza among Greek healthcare personnel (HCP) with low vaccine uptake in 2022 and 2023, highlighting the need to stay current with vaccinations against both diseases, according to an observationalstudy led by a National Public Health Organization researcher in Athens.
For the study, published yesterday in the American Journal of Infection Control, the researchers tested symptomatic HCP at four hospitals for COVID-19 and flu from November 2022 to May 2023 to estimate the number of missed workdays by disease type. The SARS-CoV-2 Omicron variant was predominant during the study period.
"To our knowledge, this is the first study to compare the burden of COVID-19 and seasonal influenza among HCP using data from the same season," the authors wrote.
A total of 9.2% of HCP were fully vaccinated, and 90.8% were partially vaccinated, against COVID-19. Flu vaccination coverage was 23.1%. HCP with flu were less likely to be current with the flu vaccine than unvaccinated workers with COVID-19 (14.0% vs 26.2%).
In total, 4,245 missed workdays were associated with COVID-19, compared with 333 for flu.
Among 5,752 HCP, 734 COVID-19 (incidence, 12.8%) and 93 flu (1.6%) cases were detected.Two COVID-infected HCP were hospitalized for 4 and 5 days, respectively.
The average number of workdays missed was 5.8 for COVID-19 and 3.6 for flu. In total, 4,245 missed workdays were associated with COVID-19, compared with 333 for flu. Analyses estimated that, on average, HCP with COVID-19 were absent for 1.91 more days than those with flu.
"The shorter duration of work absence among HCP with influenza than those with COVID-19 may be attributed to the milder clinical course of influenza, the particular seasonal influenza strain, and to differences in absenteeism policies," the researchers wrote. "Indeed, although post-COVID-19 isolation is not mandatory as in the first pandemic waves, a five-days leave is common practice for HCP in Greece. In contrast, there are no official recommendations for HCP diagnosed with influenza."
The findings underscore the value of COVID-19 and flu vaccination in protecting HCP health and protecting healthcare services from absenteeism, they concluded.
DENG MACHOL, Associated Press
1 day ago
JUBA, South Sudan (AP) South Sudan got its first batch of a new malaria vaccine on Friday from the U.N. health agency, an important step in efforts to battle a disease that is the biggest killer of children in this African country.
The more than 645,000 doses of the R21 malaria vaccine received will be distributed across 28 counties with the highest malaria burden.
In 2022, South Sudan had an estimated 2.8 million cases and 6,680 deaths from malaria. It has one of the regions highest rates of malaria incidence, with an estimated 7,630 cases and 18 people dying of the disease every day, according to the World Health Organization.
South Sudans health minister, Yolanda Awel Deng, said the new vaccine, alongside other preventive measures such as insecticide-treated bed nets and timely access to medical care, will be instrumental in a push to eliminate malaria.
Others also welcomed the development.
UNICEF South Sudan Representative Hamida Lasseko said that the governments proactive engagement and health systems preparedness are pivotal in facilitating the successful rollout of the immunization program.
Dr Humphrey Karamagi, WHOs representative for South Sudan, said the integration of the vaccine into routine immunization will enhance our ability to deliver comprehensive malaria prevention to those most at risk.
The R21 vaccine was the second malaria vaccine recommended by WHO in 2023, after the RTS,S/AS01 vaccine, which received a WHO recommendation in 2021.
The R21 vaccine has been hailed as a cheaper and a more readily available option. Research suggests it is more than 75% effective and that protection is maintained for at least another year with a booster.
FILE - Cows stand in the milking parlor of a dairy farm in New Vienna, Iowa, on Monday, July 24, 2023. The bird flu outbreak in U.S. dairy cows is prompting development of new, next-generation mRNA vaccines akin to COVID-19 shots that are being tested in both animals and people. In June 2024, the U.S. Agriculture Department is to begin testing a vaccine developed by University of Pennsylvania researchers by giving it to calves.Charlie Neibergall/AP
The bird flu outbreak in U.S. dairy cows is prompting development of new, next-generation mRNA vaccines akin to COVID-19 shots that are being tested in both animals and people.
Next month, the U.S. Agriculture Department is to begin testing a vaccine developed by University of Pennsylvania researchers by giving it to calves. The idea: If vaccinating cows protects dairy workers, that could mean fewer chances for the virus to jump into people and mutate in ways that could spur human-to-human spread.
Meanwhile. the U.S. Department of Health and Human Services has been talking to manufacturers about possible mRNA flu vaccines for people that, if needed, could supplement millions of bird flu vaccine doses already in government hands.
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If there's a pandemic, there's going to be a huge demand for vaccine, said Richard Webby, a flu researcher at St. Jude Childrens Research Hospital in Memphis. The more different (vaccine manufacturing) platforms that can respond to that, the better."
The bird flu virus has been spreading among more animal species in scores of countries since 2020. It was detected in U.S. dairy herds in March, although investigators think it may have been in cows since December. This week, the USDA announced it had been found in alpacas for the first time.
At least three people all workers at farms with infected cows have been diagnosed with bird flu, although the illnesses were considered mild.
But earlier versions of the same H5N1 flu virus have been highly lethal to humans in other parts of the world. Officials are taking steps to be prepared if the virus mutates in a way to make it more deadly or enables it to spread more easily from person to person.
Traditionally, most flu vaccines are made via an egg-based manufacturing process that's been used for more than 70 years. It involves injecting a candidate virus into fertilized chicken eggs, which are incubated for several days to allow the viruses to grow. Fluid is harvested from the eggs and is used as the basis for vaccines, with killed or weakened virus priming the body's immune system.
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Rather than eggs also vulnerable to bird flu-caused supply constraints some flu vaccine is made in giant vats of cells.
Officials say they already have two candidate vaccines for people that appear to be well-matched to the bird flu virus in U.S. dairy herds. The Centers for Disease Control and Prevention used the circulating bird flu virus as the seed strain for them.
The government has hundreds of thousands of vaccine doses in pre-filled syringes and vials that likely could go out in a matter of weeks, if needed, federal health officials say.
They also say they have bulk antigen that could generate nearly 10 million more doses that could be filled, finished and distributed in a matter of a few months. CSL Seqirus, which manufactures cell-based flu vaccine, this week announced that the government hired it to fill and finish about 4.8 million of those doses. The work could be done by late summer, U.S. health officials said this week.
But the production lines for flu vaccines are already working on this fall's seasonal shots work that would have to be interrupted to produce millions more doses of bird flu vaccine. So the government has been pursuing another, quicker approach: the mRNA technology used to produce the primary vaccines deployed against COVID-19.
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These messenger RNA vaccines are made using a small section of genetic material from the virus. The genetic blueprint is designed to teach the body how to make a protein used to build immunity.
The pharmaceutical company Moderna already has a bird flu mRNA vaccine in very early-stage human testing. In a statement, Moderna confirmed that we are in discussions with the U.S. government on advancing our pandemic flu candidate."
Similar work has been going on at Pfizer. Company researchers in December gave human volunteers an mRNA vaccine against a bird flu strain that's similar to but not exactly the same as the one in cows. Since then, researchers have performed a lab experiment exposing blood samples from those volunteers to the strain seen in dairy farms, and saw a notable increases in antibody responses," Pfizer said in a statement.
As for the vaccine for cows, Penn immunologist Scott Hensley worked with mRNA pioneer and Nobel laureate Drew Weissman to produce the experimental doses. Hensley said that vaccine is similar to the Moderna one for people.
In first-step testing, mice and ferrets produced high levels of bird flu virus-fighting antibodies after vaccination.
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In another experiment, researchers vaccinated one group of ferrets and deliberately infected them, and then compared what happened to ferrets that hadn't been vaccinated. All the vaccinated animals survived and the unvaccinated did not, Hensley said.
The vaccine was really successful, said Webby, whose lab did that work last year in collaboration with Hensley.
The cow study will be akin to the first-step testing initially done in smaller animals. The plan is for initially about 10 calves to be vaccinated, half with one dose and half with another. Then their blood will be drawn and examined to look for how much bird flu-fighting antibodies were produced.
The USDA study first will have to determine the right dose for such a large animal, Hensley said, before testing if it protects them like it did smaller animals.
What scares me the most is the amount of interaction between cattle and humans, Hensley said.
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Were not talking about an animal that lives on a mountain top," he said. "If this was a bobcat outbreak Id feel bad for the bobcats, but thats not a big human risk.
If a vaccine reduces the amount of virus in the cow, then ultimately we reduce the chance that a mutant virus that spreads in humans is going to emerge, he said.
The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institutes Science and Educational Media Group. The AP is solely responsible for all content.
Even a peep of news about a new flu pandemic is enough to set scientists clucking about eggs.
They worried about them in 2005, and in 2009, and they're worrying now. That's because millions of fertilized hen eggs are still the main ingredient in making vaccines that, hopefully, will protect people against the outbreak of a new flu strain.
"It's almost comical to be using a 1940s technology for a 21st-century pandemic," said Rick Bright, who led the Health and Human Services Department's Biomedical Advanced Research and Development Authority during the Trump administration.
It's not so funny, he said, when the currently stockpiled formulation against the H5N1 bird flu virus requires two shots and a whopping 90 micrograms of antigen, yet provides just middling immunity. "For the U.S. alone, it would take hens laying 900,000 eggs every single day for nine months," Bright said.
click to expand
And that's only if the chickens don't get infected.
The spread of an avian flu virus has decimated flocks of birds (and killed barn cats and other mammals). Cattle in at least nine states and at least two people in the U.S. have been infected, enough to bring public health attention once again to the potential for a global pandemic.
So far, the only confirmed human cases of infection were dairy workers in Texas and Michigan, both of whom suffered pink eye and quickly recovered. Yet the virus's spread into multiple species over a vast geographic area raises the threat that further mutations could create a virus that spreads from human to human through airborne transmission, causing respiratory infections.
If they do, prevention starts with the egg.
To make raw material for an influenza vaccine, virus is grown in millions of fertilized eggs. Sometimes it doesn't grow well, or it mutates to a degree that the vaccine product stimulates antibodies that don't neutralize the virus or the wild virus mutates to an extent that the vaccine doesn't work against it. And there's always the frightening prospect that wild birds could carry the virus into the henhouses needed in vaccine production.
"Once those roosters and hens go down, you have no vaccine," Bright said.
Since 2009, when an H1N1 swine flu pandemic swept around the world before vaccine production could get off the ground, researchers and governments have been looking for alternatives. Billions of dollars have been invested into vaccines produced in mammalian and insect cell lines that don't pose the same risks as egg-based shots.
"Everyone knows the cell-based vaccines are better, more immunogenic, and offer better production," said Amesh Adalja, an infectious disease specialist at Johns Hopkins University's Center for Health Security. "But they are handicapped because of the clout of egg-based manufacturing."
The companies that make the cell-based influenza vaccines, CSL Seqirus and Sanofi, also have billions invested in egg-based production lines that they aren't eager to replace. And it's hard to blame them, said Nicole Lurie, HHS' assistant secretary for preparedness and response under President Barack Obama who is now an executive director of CEPI, the global epidemic-fighting nonprofit.
"Most vaccine companies that responded to an epidemic Ebola, Zika, COVID ended up losing a lot of money on it," Lurie said.
Exceptions were the mRNA vaccines created for COVID, although even Pfizer and Moderna have had to destroy hundreds of millions of doses of unwanted vaccine as public interest waned.
Pfizer and Moderna are testing seasonal influenza vaccines made with mRNA, and the government is soliciting bids for mRNA pandemic flu vaccines, said David Boucher, director of infectious disease preparedness at HHS' Administration for Strategic Preparedness and Response.
Bright, whose agency invested a billion dollars in a cell-based flu vaccine factory in Holly Springs, North Carolina, said there's "no way in hell we can fight an H5N1 pandemic with an egg-based vaccine." But for now, there's little choice.
BARDA has stockpiled hundreds of thousands of doses of an H5N1-strain vaccine that stimulates the creation of antibodies that appear to neutralize the virus now circulating. It could produce millions more doses of the vaccine within weeks and up to 100 million doses in five months, Boucher told KFF Health News.
But the vaccines currently in the national stockpile are not a perfect match for the strain in question. Even with two shots containing six times as much vaccine substance as typical flu shots, the stockpiled vaccines were only partly effective against strains of the virus that circulated when those vaccines were made, Adalja said.
However, BARDA is currently supporting two clinical trials with a candidate vaccine virus that "is a good match for what we've found in cows," Boucher said.
Flu vaccine makers are just starting to prepare this fall's shots but, eventually, the federal government could request production be switched to a pandemic-targeted strain.
"We don't have the capacity to do both," Adalja said.
For now, ASPR has a stockpile of bulk pandemic vaccine and has identified manufacturing sites where 4.8 million doses could be bottled and finished without stopping production of seasonal flu vaccine, ASPR chief Dawn O'Connell said on May 22. U.S. officials began trying to diversify away from egg-based vaccines in 2005, when avian flu first gripped the world, and with added vigor after the 2009 fiasco. But "with the resources we have available, we get the best bang for our buck and best value to U.S. taxpayers when we leverage the seasonal infrastructure, and that's still mostly egg-based," Boucher said.
Flu vaccine companies "have a system that works well right now to accomplish their objectives in manufacturing the seasonal vaccine," he said. And without a financial incentive, "we are going to be here with eggs for a while, I think."
KFF Health News is a national newsroom that produces in-depth journalism about health issues and is one of the core operating programs at KFF the independent source for health policy research, polling, and journalism.
Weve come a long way in the fight against polio the infectious disease that used to paralyze hundreds of thousands of people each year. Most of them were children. Eradication is possible, but the last stretch has proven difficult.
Two of the three serotypes (distinct types within a species of virus) of wild poliovirus have already been eradicated.
However, two big challenges remain in crossing the finish line. One is eliminating the last serotype of wild poliovirus. Another is containing vaccine-derived polioviruses, which arose from oral polio vaccines in rare circumstances and spread in some regions where protection against the disease declined.
The world can overcome these hurdles. We can use new vaccines to contain them and improve testing, outbreak responses, and sanitation.
The chart below shows the dramatic decline in polio cases.
This was possible due to effective vaccination efforts with two types of vaccine: inactivated polio vaccines (IPV), developed by Jonas Salk in 1955, and oral polio vaccines (OPV), developed by Albert Sabin in 1961.
Improvements in providing clean water and sanitation have also helped to reduce the spread of poliovirus through contaminated water and food and the risks of other infections, which prevent children from developing immunity against polio.1
In the early 1980s, there were around 400,000 estimated cases annually. In the last few years, there have been around 4,000. Thatsa hundred-fold decline. Millions of children have been spared lifelong paralysis.
Wild poliovirus has three serotypes.The three serotypes are distinct types of poliovirus with protein structures that differ sufficiently that protection from one doesnt protect from the other.
The world has eradicated wild poliovirus serotypes 2 and 3.2
The world is, therefore, very close to eradicating all serotypes of wild poliovirus globally.
As shown in the map below, only two countries Afghanistan and Pakistan are still endemic for wild poliovirus serotype 1 (WPV1).
But as the chart shows, the number of cases is now very low. In 2023,only six cases of wild polio were reported in Afghanistan and another six in Pakistan.
By testing widely to identify potential cases, working with local communities in hard-to-reach areas and at borders, and improving vaccination rates and sanitation, this goal is within reach.4
Although the absolute number of cases is much lower than in the past, most cases recently have come from vaccine-derived polioviruses (VDPVs), as shown in the chart below.5
Vaccine-derived polioviruses can arise from the weakened virus in the oral polio vaccine if it has mutated significantly over time in vaccinated people and reverted to the original strain of polio.
Oral polio vaccines are used in poorer countries because they are much easier to administer (as oral drops) and cheaper to manufacture than inactivated polio vaccines, which are given by injection.6
People with immune deficiencies are at higher risk of the vaccine reverting because they can sustain longer infections, giving the virus more time to evolve.7
It can then spread and cause new outbreaks if immunity has fallen in communities. So, somewhat counterintuitively, communities with lower vaccination coverage are more vulnerable to vaccine-derived polio.8
So far, most cases of vaccine-derived poliovirus have come from vaccine-derived polioviruses of serotype 2 known as VDPV2 which can mutate faster than other serotypes, making it more likely to revert than other serotypes.9
In addition, there were interruptions in vaccination against polio serotype 2 in 2016, when vaccination against that particular serotype was switched from the oral to the inactivated polio vaccine. It was harder to provide inactivated polio vaccines at scale in poorer regions and reach every child, leading to a rise in cases.10
Since 2021, new oral polio vaccines against serotype 2 have been used to prevent further outbreaks of VDPV2.
These are much more genetically stable than the previous oral polio vaccine and much less likely to mutate or potentially revert to the original strain.11
They have already been rolled out widely and helped effectively control outbreaks of VDPV2.12
New oral polio vaccines against serotypes 1 and 3 are still in development.13
In addition, new types of inactivated polio vaccines are also being developed. For example, some candidate vaccines can be administered through skin patches instead of injections. These could be cheaper, easier to provide, and unable to revert to the original strain.14
These new technologies will be crucial in preventing further outbreaks as we approach the ultimate goal of polio eradication.
To achieve polio eradication, its crucial to contain every last case quickly to prevent the spread of polio and protect children from this debilitating disease.
We can use new vaccines, increase polio testing, and improve access to clean water and sanitation.
Together, we can successfully close the chapter on polio, which would be a major victory for humanity.
Edouard Mathieu, Max Roser, and Hannah Ritchie provided helpful feedback on this article.
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Today in Science, astudy shows that unflagged, factual but misleading Facebook posts reduced the intent to receive the COVID-19 vaccine 46 times more than did false posts flagged by fact-checkers as misinformation, which the authors say points to the need to consider the reach and impact of content rather than just its veracity.
The researchers, from the Massachusetts Institute of Technology (MIT) and the University of Pennsylvania (UPenn), surveyed thousands of participants about the influence of the headlines from 130 vaccine-related news stories on their intent to vaccinate. They also asked a separate group of people to rate the headlines on attributes such as plausibility and political bent.
Then the team extrapolated the survey results to predict the influence of13,206 vaccine-related Facebook links in the first 3 months of the COVID-19 vaccine rollout (January to March 2021) on the vaccination intentions of the platform's roughly 233 million US users.
"We posit that two conditions must be met for content to have widespread impact on people's behavior: People must see it, and, when seen, it must affect their behavior," the researchers wrote. "That is, we define 'impact' as the combination of exposure and persuasive influence."
Posts containing false claims about the COVID-19 vaccine (eg, microchips being placed in vaccines)lowered vaccination intentions by 1.5 percentage points, and content suggesting that the vaccine was harmful to health also reduced vaccination intentions, regardless of any effect of the headline's truthfulness.
Flagged links to misinformation received 8.7 million views, accounting for 0.3% of the 2.7 billion vaccine-related link views. In contrast, stories that fact-checkers didn't flag but that still implied that vaccines were harmfulmany of them from credible mainstream news outletswere viewed hundreds of millions of times. One example of unflagged yet misleading content was a story about a rare case of a young, healthy person who died after receiving the COVID vaccine.
The links that fact-checkers flagged as misinformation were, when viewed, more likely to reduce vaccine intentions than unflagged links. But after weighting each link's persuasive effect by the number of views, the effect of unflagged vaccine-skeptical posts eclipsed that of flagged falsities.
Unflagged vaccine-skeptical content reduced vaccination intention by 2.28 percentage points per Facebook user, compared with 0.05 percentage points for flagged contenta 46-fold difference.
Although flagged posts had more of an impact when viewed, differences in exposure almost entirely determined the ultimate impact.
For example, a single vaccine-skeptical Chicago Tribunearticle, "A healthy doctor died two weeks after getting a COVID vaccine; CDC is investigating why," was viewed by more than 50 million Facebook users (over 20% of Facebook's US users) and garnered more than six times the number of views than all flagged content combined.
A COVID-19 antigen rapid test
A new variant of COVID-19, known as FLiRT, is now the most dominant strain in the U.S. This variant, which evolved from the omicron strain, is characterized by changes in its spike protein the part of the virus that binds to host cells. Dr. Matthew Binnicker,director of theClinical Virology Laboratoryat Mayo Clinic, says that these changes could increase the virus' ability to infect cells and evade the immune system, even in people who have previously been infected or vaccinated.
"This variant can evade the immune response more effectively than prior versions of the virus. If you've been infected, or you've been vaccinated, and you've got some antibodies in your system, those antibodies may not recognize the protein on the surface of the virus as well," says Dr. Binnicker.
According to the Centers for Disease Control and Prevention (CDC), this new variant is nowresponsiblefor more than 28% of COVID-19 cases in the U.S. Dr. Binnicker says there is a potential for an increase in cases during the summer months, with a more significant surge expected in the fall and winter.
"I anticipate we'll see an uptick in cases with this more transmissible virus that can evade the immune system. But what I'm really watching are the fall and winter months because that's typically when we see the largest surge in respiratory viral infections," he says.
Watch: Dr. Matthew Binnicker discusses COVID-19 FLiRT strains
Journalists: Broadcast-quality sound bites are available in the downloads at the bottom of the posts. Name super/CG: Matthew Binnicker, Ph.D./Laboratory Medicine and Pathology/Mayo Clinic
For those who are vaccinated, antibodies are present to combat the virus. However, the effectiveness of these antibodies can vary with different virus variants.
"With this latest round of variants, this FLiRT variant, the antibodies that you have from past vaccination may not bind and neutralize the virus as well. If you've been infected or vaccinated in the past three to four months, youre probably going to have antibodies that are going to recognize these newer viruses effectively. And it will help you keep from getting really sick and may even help prevent you from coming down with any symptoms," says Dr. Binnicker.
"If you were infected or vaccinated more than six months ago, you may not have as good of protection, and you may come down with a subsequent infection with the typical symptoms of COVID," he adds.
The symptoms of this variant are consistent with other variants and include:
Receiving an updated vaccine will help protect you from the newer strain.
In a recent essay in the journal Monash Bioethics Review, oncologist Vinay Prasad and health researcher Alyson Haslam provide a comprehensive after-the-fact assessment of the federal government's rollout of the COVID-19 vaccines.
Their basic takeaway is that the vaccines were a "scientific success"tarnished by flawed federal vaccine policy.
The two argue the tremendous benefits of the COVID-19 vaccines for the elderly were undercut by government guidance and messaging that pushed vaccines on the young, healthy, and previously infected when data suggested that wasn't worthwhile (and was in some cases counterproductive).
Worse still, the government even pushed vaccine mandates when it was increasingly clear the vaccines did not stop COVID-19 transmission, they argue.
To correct these errors for future pandemic responses, Prasad and Haslam recommend performing larger vaccine trials and collecting better data on vaccine performance in lower-risk populations. They also urge policy makers to be more willing to acknowledge the tradeoffs of vaccination.
That's sound advice. We'll have to wait and see if the government adopts it come the next pandemic.
There is one policy that they don't mention and doesn't totally depend on the government getting better at judging the risks of new vaccines: Charge people for them.
Had the government not provided COVID-19 vaccines for free and shielded vaccine makers and administrators from any liability for adverse reactions, prices could have better rationed vaccine supply and better informed people about their risks and benefits.
Without prices, people were instead left with flawed government recommendations, incentives, and rationing schemes.
Those who recall early 2021 will remember the complex, often transparently silly eligibility criteria state governments set up to ration scarce vaccine supplies. This often involved prioritizing younger, healthier, often politically connected "essential workers" over elderly people.
Prasad and Haslam criticize this as a government failure to prioritize groups at most risk of dying from COVID-19.
"While the UK prioritized nursing home residents and older individualsthe US included essential workers, including young, resident physicians," write Prasad and Haslam. "Health care workers face higher risks of acquiring the virus due to occupation (though this was and is offset by available personal protective equipment), but this was less than the elevated risk of death faced by older individuals."
Yet if the government hadn't assigned itself the role of distributing vaccines for free, it wouldn't have been forced into this position of rationing scarce vaccine supplies.
Demand for the vaccine is a function of the vaccine's price. Since the vaccine's price was $0, people who stood to gain comparatively less from vaccination and people for whom a vaccine would be lifesaving were equally incentivized to receive it.
Consequently, everyone rushed to get in line at the same time. The government then had to decide who got it first and predictably made flawed decisions.
Had vaccine makers been left to sell their product on an open market (instead of selling doses in bulk to the federal government to distribute for free), the elderly and those most at risk of COVID-19 would have been able to outbid people who could afford to wait longer. Perhaps more lives could have been saved.
Over the course of 2021, the supply of vaccines outgrew demand.
At the same time, as Prasad and Haslam recount, an increasing number of people (particularly young men) were developing myocarditis as a result of vaccination. Nevertheless, the government downplayed this risk, continued to urge younger populations to get vaccinated, and failed to collect data about the potential risks of vaccination.
That's all a failure of the government policy. Even if the government was slow to adjust its recommendations, prices could have played a constructive role in informing people about their own risk-reward tradeoff of getting vaccinated.
If a 20-year-old man who'd already had COVID-19 had to spend something to get vaccinated, instead of nothing, fewer would have. Prasad and Haslam argue that would have been the right call healthwise.
Without prices, that hypothetical 20-year-old's decision was informed mostly by government guidance, and, later, government mandates.
The government compounded this lack of prices by giving liability shields to vaccine makers. As it stands right now, no one is able to sue the maker of a COVID-19 vaccine should they have an adverse reaction. (Unlike standard, non-COVID vaccines, people are also not allowed to sue the government for compensation for the vaccine injuries.)
If pharmaceutical companies had to charge individual consumers to make money off their vaccines, and if those prices had to reflect the liability risks of the side effects some number of people would inevitably have, consumers would have been even better informed about the risks and rewards of vaccination.
One might counter that individual consumers aren't in a position to perform this risk-reward calculation on their own.
That ignores the ways that other intermediaries in a better position to evaluate the costs and benefits of vaccination could contribute to the price signals individuals would use to make their own decisions.
One could imagine an insurance company declining to cover COVID-19 vaccines for the aforementioned healthy 20-year-old while subsidizing their elderly customers to get the shot. (This is, of course, illegal right now. The Affordable Care Act requiresmost insurance plansto cover the costs of vaccination for everyone.)
Instead, the financial incentives that were attached to vaccination were another part of the federally subsidized vaccination campaign.
State Medicaid programs paid providers bonuses for the number of patients they vaccinated (regardless of how at risk of COVID-19 those patients were). State governments gave out gift cardsto those who got vaccinated and entered them in lotteries to win even bigger prizes.
Leaving it up to private companies to produce and charge for vaccines would have one added benefit: It would make it much more difficult for the government to mandate vaccines or otherwise coerce people into getting them.
One of the things that made it easy for local and state governments to bar the unvaccinated from restaurants and schools was that they also had a lot of free, federally subsidized doses to give away. People didn't have a real "excuse" not to get a shot.
Had people been required to pay for vaccines, it would have been more awkward and much harder (politically and practically) to mandate that they do so.
Economist Alex Tabarrok likes to say that a "price is a signal wrapped up in an incentive." They signal crucial information and then incentivize people to act on that information in a rational, efficient way.
By divorcing COVID-19 vaccines from real price signals, we were left with an earnest, government-led vaccination effort. That effort got a lot of lifesaving vaccines to a lot of people.
But it also encouraged and subsidized people to get vaccinated when it was probably not a necessary or even good idea. When not enough people got vaccinated, governments turned to coercive mandates.
Number of children receiving COVID-19 vaccines
A total of 5,197,925 young people aged 517 years, comprising 1,842,159 children aged 511 years and 3,355,766 adolescents aged 1217 years were included in the study. 4,347,781 young adults aged 1824 years, were included as a comparison. The characteristics of the young people included in the study are detailed in Table1 and Supplementary Table1.
In children aged 511 years, 32% (n=581,545) received at least one dose of COVID-19 vaccine and 16% (n=303,118) received a second dose within the study period. Over 99.9% of 511-year-olds who received at least one COVID-19 vaccine dose received the BNT162b2 vaccine (Table2). 82% (n=1,508,661) of children in this age group had a positive SARS-CoV-2 test recorded between 8th December 2020 and 7th August 2022, 0.4% (n=5665) of whom received their first COVID-19 vaccine dose prior to their first recorded positive SARS-CoV-2 test (Table2).
In adolescents aged 1217 years, 86% (n=2,882,229) received a first dose of COVID-19 vaccine, 67% (n=2,254,214) received a second dose and 14% (n=454,868) received a third dose (Table2).
The characteristics of the population excluded from the self-controlled case series analysis (i.e. those who did not receive any COVID-19 vaccine and did not have a positiveSARS-CoV-2 test recorded during the study period) are presented in Supplementary Table2.
In children aged 511 years, we did not observe an increased risk of any of the pre-specified outcomes in the 142 days following any dose COVID-19 vaccine with BNT162b2, mRNA-1273 or ChAdOX1 (Table3). However, given that less than 0.1% of vaccinated 5-11-year-olds received a ChAdOX1 or mRNA-1273 vaccine, the probability of type II errors was high as the sample size was too small to detect statistically significant associations for these vaccines.
The clinical characteristics of all children hospitalised with a pre-specified safety event are shown in Supplementary Table3. Supplementary Tables47 show the incidence rate ratios (IRR) and 95% confidence intervals (CI) for all outcomes 142 days and in weekly risk periods following each vaccine dose in 511-year-olds in males and females separately, and the effect of ethnicity on the risk of each outcome.
In the 142 days after the first and second doses of BNT162b2, we observed an increased risk of myocarditis in adolescents aged 1217 years (IRR 1.92, 95%CI 1.083.43 and IRR 2.96, 95%CI 1.655.32 for first and second dose, respectively) (Table4). We estimated that an additional 3 (95%CI 05) cases per million exposed would be anticipated after the first dose and 5 (95%CI 36) after the second dose (Fig.1). When we split the risk period into weekly blocks, the increased risk was restricted to 114 days following each dose (Supplementary Table8). There was also an increased risk of hospitalisation with epilepsy (IRR 1.17, 95%CI 1.001.37; excess events per million: 12, 95%CI 023) in the 142 days following the second dose of BNT162b2 (Table4, Fig.1).
Estimated number of excess events per million (95% CI) based on incidence rate ratios of each outcome in the 142 days following vaccination or SARS-CoV-2 positive test compared to baseline period are presented where there were at least five events during the exposure period and when number of excess events is greater than zero. Data available from 8th December 2020 and 7th August 2022. Table4 contains the data presented in this figure. MIS-C Multisystem inflammatory syndrome; ITP Idiopathic or immune thrombocytopenic purpura, ADEM Acute disseminated encephalomyelitis.
In the sex-stratified analysis, the increased risk of myocarditis after the first dose of BNT162b2 was only observed in females (IRR 4.01, 95%CI 1.3312.09; excess events per million: 3, 95%CI 14), while the increased risk following the second dose was observed in males only (IRR 2.87, 95%CI 1.505.51; excess events per million: 9, 95%CI 411) (Supplementary Figs.1 & 2, Supplementary Tables4 & 5). We additionally observed an increased risk of demyelinating disease, restricted to females (IRR 2.41, 95%CI 1.06-5.48; excess events per million: 4, 95%CI 06) following the second dose of BNT162b2. Of the eight female adolescents who experienced demyelinating disease in the 142 days following a second dose of BNT162b2, five were coded as optic neuritis.
In a post hoc analysis investigating differences in risk between children of different ethnic backgrounds, we found that the risk of anaphylaxis following a second dose of BNT162b2 in adolescents with non-white ethnicity was higher relative to the risk in adolescents with white ethnicity (relative IRR 2.55, 95%CI 1.006.46) (Supplementary Table6). However, when the analysis was restricted to the subgroup of adolescents from non-white ethnic backgrounds, the risk of anaphylaxis in the 142 days following a second dose of BNT162b2 was not significantly increased compared to the baseline period (IRR 1.69, 95%CI 0.803.54) (Supplementary Table6). We did not identify any differences in vaccine safety between white and non-white ethnicity for any of the other pre-specified outcomesin under-18s.
We found no evidence for significantly increased risks for any of the pre-specified outcomes in the 142 days following a first, second or third dose of mRNA-1273 vaccine in 1217-year-olds (Table4). However, this analysis lacked power to detect statistically significant associations, except for very large effect sizes, as less than 0.1% of adolescents received a first or second dose of mRNA-1273 vaccine.
There was an increased risk of hospitalisation with epilepsy 142 days after a first dose of ChAdOX1 (IRR 1.93, 95%CI 1.103.39), with an additional 705 (95%CI 1291033) cases expected per million exposed (Table4). This increased risk was restricted to females in the sex-stratified analysis (IRR 2.26, 95%CI 1.034.94) with an additional 813 (95%CI 441164) hospitalisations with epilepsy expected per million female adolescents exposed (Supplementary Table4).
We also observed an increased risk of appendicitis in the 142 days following the second dose of ChAdOX1 (IRR 4.64, 95%CI 1.7712.17; excess events per million: 512, 95%CI 283599) (Table4).
The IRRs and 95% CIs for all outcomes 142 days and in weekly risk periods following each vaccine dose in 1217-year-olds in males and females separately, and the effect of ethnicity on the risk of each outcome, are presented in Supplementary Figs.1 & 2, Supplementary Tables46 & 8.
In children aged 5-11 years who had received at least one dose of COVID-19 vaccine before the date that their positive SARS-CoV-2 test was recorded, we did not observe increased risks of any of the pre-specified outcomes in the 142 days following SARS-CoV-2 infection. In children who had not been vaccinated against COVID-19 prior to infection, there was an increased risk of hospital admission with MIS-C following a SARS-CoV-2 positive test (IRR 11.52, 95%CI 9.2514.36), with an additional 137 (95%CI 134140) cases expected per million exposed (Table3, Fig.2). In the sex-stratified analysis, the risk of MIS-C was slightly greater in male children (IRR 12.00, 95%CI 8.9216.12; excess events per million: 162, 95%CI 157-166) compared to female children (IRR 11.13, 95%CI 7.9615.57; excess events per million: 124, 95%CI 119127) (Supplementary Figs.3 & 4, Supplementary Tables4 & 5). The increased risk was mainly observed in the 2242 days following the date that the positive SARS-CoV-2 test was recorded (Supplementary Table7).
Estimated number of excess events per million (95% CI) based on incidence rate ratios of each outcome in the 142 days following SARS-CoV-2 positive test compared to baseline period are presented where there were at least five events during the exposure period and when number of excess events is greater than zero. Data available from 8th December 2020 and 7th August 2022. Table3 contains the data presented in this figure. MIS-C Multisystem inflammatory syndrome, ITP Idiopathic or immune thrombocytopenic purpura, ADEM Acute disseminated encephalomyelitis.
We also observed increased risks of hospital admission for myositis, myocarditis, acute pancreatitis and ADEM following SARS-CoV-2 infection before vaccination(Table3, Fig.2). In the sex-stratified analyses, we additionally identified increased risks of ITP (in both sexes) and anaphylaxis (in females only) (Supplementary Figs.3 & 4, Supplementary Tables4 & 5).
The IRRs and 95% CIs for all outcomes 142 days following SARS-CoV-2 infection in 511-year-olds in males and females separately, and the effect of ethnicity on the risk of each outcome, are presented in Supplementary Figs.3 & 4, Supplementary Tables4, 5, 6 & 7.
In adolescents aged 1217 years, we observed an increased risk of MIS-C (IRR 12.38, 95%CI 8.8817.28; excess events per million: 84, 95%CI 8186) in the 142 days following a SARS-CoV-2 infection in those who had not been vaccinated prior to SARS-CoV-2 infection (Table4, Fig.1). In the sex-stratified analysis, male adolescents were at higher risk of MIS-C following infection compared to females (IRR 12.33, 95%CI 8.3118.31and IRR 13.11, 95%CI 6.9024.91 in males and females, respectively), with an additional 131 (95%CI 126135) cases expected per million males exposed compared to 48 (95%CI 44-50) in females (Supplementary Figs.1 & 2, Supplementary Tables4 & 5).
We also observed increased risks ofhospitalisation with myocarditis, ITP and epilepsy in the 1-42 days following SARS-CoV-2 infection in adolescents who had not been vaccinated against COVID-19 prior to infection as well as an increased risk of hospitalisation with epilepsy in those who had received at least one vaccine dose prior to infection (Table4, Fig.1). In the sex-stratified analysis, the increased risks ofhospitalisation with myocarditis and epilepsy were restricted to males while the increased risk of ITP following infection was only observed in females (Supplementary Figs.1 & 2, Supplementary Tables4 & 5). We additionally identified increased risks of appendicitis (in females only) and anaphylaxis (in males only) following SARS-CoV-2 infection.
The IRRs and 95% CIs for all outcomes 142 days following SARS-CoV-2 infection in 12-17-year-olds in males and females separately, and the effect of ethnicity on the risk of each outcome, are presented in Supplementary Figs.1 & 2, Supplementary Tables4, 5, 6 & 8.
The results for all analyses in young adults aged 18-24 years are presented in Supplementary Tables6 & 9.
The robustness of the results of the self-controlled case series analyses were assessed by (1) checking that the risk of outcomes during the pre-vaccination period (month prior to vaccination to account for potential bias of people with recent hospitalisation being less likely to get vaccinated) was lower than the baseline period and (2) checking that the risk of the positive control outcome (anaphylaxis) was higherfollowing vaccination or SARS-CoV-2 infection than the baseline period. In the vast majority of analyses the estimates of the pre-vaccination period and the risk of anaphylaxis following vaccination or SARS-CoV-2 agreed with what was expected (SupplementaryTables8 & 9).
Our matched cohort analysis included 1,580,869 children aged 511 years and 1,535,341 adolescents aged 1217 years. Characteristics of the cohort are detailed in Supplementary Table10.
Incidence rates of vaccine safety outcomes in the 142 days following each vaccine dose and following SARS-CoV-2 infection in vaccinated and unvaccinated children are presented in Supplementary Table11. Incidence rates for all outcomes were significantly higher following SARS-CoV-2 infection compared to COVID-19 vaccination.
We matched 160,262 children aged 511 years and 848,186 adolescents aged 1217 years who had received at least one dose of COVID-19 vaccine to a child of the same age and sex who had not received any COVID-19 vaccine doses by the date of the vaccinated childs first vaccine dose (characteristics of matched cohort reported in Supplementary Table12).
As in the self-controlled case series analysis, we identified an increased risk of hospitalisation with epilepsy in the 142 days following a second dose of COVID-19 vaccine with BNT162b2 in 12-17-year-olds (unadjusted IRR 1.77, 95%CI 1.052.99, adjusted IRR 3.88, 95%CI 1.2711.86), but did not find significantly increased risks of appendicitis or myocarditis with BNT162b2 vaccination in adolescents (Supplementary Table13).
We identified additional increased risks of anaphylaxis and appendicitis in 12-17-year-olds following a first dose of BNT162b2 (unadjusted IRR 3.71, 95%CI 1.2311.14 and unadjusted IRR 1.37, 95%CI 1.051.80, respectively) and an increased risk of hospitalisation with epilepsy following a first dose with BNT162b2 in 511-year-olds, although the confidence interval was very wide reflecting the uncertainty of the estimate (unadjusted IRR 16.00, 95%CI 2.12120.65) (Supplementary Table13).
In general, the estimates from the matched cohort study were in agreement with the results from the self-controlled case series analysis in under-18s.
Unadjusted IRRs and IRRs adjusted for self-reported ethnicity (white, non-white, missing), quintile of deprivation (based on Townsend score) and presence of comorbidity (yes/no) for each outcome are reported in Supplementary Table13.
