The Biden administration announced this week that most Americans will receive COVID booster shots eight months after receiving their second dose of Pfizer’s or Moderna’s messenger RNA (mRNA) vaccinations.
People will begin receiving boosters on September 20 pending approval from the US Food and Drug Administration and the Centers for Disease Control and Prevention’s vaccine advisory council.
Workers in the healthcare industry and residents of nursing homes will be among the first to benefit.
The news arrived as scientists debated whether such boosters are necessary, who should receive them, and when they should be given.
It came less than a week after the CDC suggested that patients who are moderately or severely immunocompromised get a second vaccination because evidence had surfaced that two doses might not be enough.
Data from Israel, vaccine manufacturers, and many U.S. studies reveal that vaccination-induced immunity to COVID fades after six months and that immunizations are less effective at preventing mild or moderate sickness from the coronavirus’s renowned Delta form than they were against earlier strains.
Two mRNA vaccine doses, on the other hand, appear to provide substantial protection against severe sickness and mortality.
In a White House press briefing on Wednesday, Anthony Fauci, President Joe Biden’s main medical adviser, said, “If you wait for something bad to happen…, you’re far behind your real full capability of being responsive…”
“You have to stay one step ahead of the virus.”
Some specialists disagree that most healthy people will require boosters.
Furthermore, the World Health Organization has stated that it is unethical for wealthy countries to give vaccines to those who have previously been vaccinated while so much of the world’s population has yet to receive a single dose.
The Biden administration, on the other hand, has defended its choice, claiming that the US government should not be forced to choose between safeguarding its citizens and defending the rest of the world.
Several scientists, on the other hand, believe that putting more vaccines into the hands of the unvaccinated would be a far more successful method for protecting the population than giving booster doses to individuals who have previously been vaccinated.
Shane Crotty, a virologist and professor at the La Jolla Institute for Immunology, and Céline Gounder, an infectious disease specialist and epidemiologist at NYU and Bellevue Hospital in New York City, and a member of the Biden-Harris Transition COVID-19 Advisory Board, spoke with Scientific American about booster shots and other topics.
Do we need any further shots? And, if so, who is the most in need of them?
GOUNDER: Even after time and against the Delta variation, the data show that immunizations remain substantially protective against severe disease, hospitalization, and death.
We’re not seeing a decline in hospitalization and death protection. In terms of infection, we’re seeing a reduction in immunity to the Delta form.
Highly immunocompromised persons, such as recipients of solid organ transplants, those with AIDS, and those on highly immunosuppressive medicines for cancer or autoimmune disease, all have a lower response to immunization.
Some people will benefit from a higher dose, but not everyone.
Also, patients in nursing homes, where we’ve seen outbreaks become disastrous, resulting in serious sickness and death.
Caregivers who have not been immunized can spread the infection to nursing homes.
Offering extra doses to nursing home residents makes sense, but giving them to caregivers would likely have a greater impact.
Aside from that, there is currently no evidence to warrant administering additional doses to the general public in the United States.
CROTTY: It all boils down to one word: “need.” Different people have different interpretations.
The data over the previous month has created enough doubt regarding Delta and how long protection lasts that I believe a government decision to treat boosters as “better safe than sorry” is fair.
You don’t want to make a hasty decision.
Immunocompromised persons, without a doubt, require a booster.
There were hints in May, June, and July that there were a lot of immunocompromised people who didn’t respond well to two doses but did better with three.
There has now been a scientific investigation that clearly showed that a third dose helps some groups of immunocompromised persons.
People had a good antibody response to a third dosage if they had good T cells [a type of immune cell] after one to two doses.
Should boosters be given to people above the age of 80? That makes perfect sense.
It’s not a vast population, but we know they’re in grave danger.
What about people in their 70s, 60s, and 50s? Those are primarily policy considerations.
How effective are vaccine-induced immune responses?
CROTTY: The vaccine appears to produce high-quality immunological memory.
The Moderna vaccine was the subject of an article published in Science last week that showed antibodies six months after the second immunization, and there wasn’t much of a reduction.
Six months after receiving an mRNA vaccination, we released the first findings on T cell memory (a low dose of Moderna).
Between one and six months following vaccination, there was essentially no change in T cell memory.
It will most likely last for at least a year.
Take a look at the data from England, where they had a lot of Delta and the vaccines performed wonders.
In the Delta wave, compared to the winter wave [when the Alpha variety was initially identified in the U.K.], there was a huge difference in hospitalizations and deaths.
Is it necessary to use boosters? Hospitalizations and deaths are not covered.
Will boosters be effective? Yes, data from the Moderna clinical trial, as well as data from Pfizer, support this.
Antibody titers will be replenished. Do we, however, require them? Uncertain.
What do you make of Israeli evidence suggesting that vaccination immunity declines dramatically over time?
CROTTY: In terms of vaccine fading, the Israel data is the best available.
Israeli officials, on the other hand, have yet to publish anything [in a scientific journal]. I get my information from epidemiologists.
The importance of confounding factors cannot be overstated. In February and March, Israel had several [apparent] vaccine effectiveness issues.
They finally published a study demonstrating that the vaccine was effective.
Now it appears that there is a drop [in effectiveness], possibly a significant decline. We may never find out.
GOUNDER: The Israel data has some serious flaws. They are muddled by age and other variables.
They must be shared in their whole, not only as PowerPoint presentations. I would never make a judgment based on information from Israel.
Data from the lab can sometimes be problematic.
The strongest predictor of protection is so-called neutralizing antibodies.
It’s not evident when you measure them six months to a year later.
Your blood would be mud if you had antibodies to every infection you’ve ever had.
It’s a different question if you noticed memory B and T cells, which are immunological cells. Antibodies, on the other hand, are expected to decline.
Should Johnson & Johnson vaccine recipients seek a booster?
CROTTY: Those who received the Johnson & Johnson vaccine should get a second dosage, in my opinion.
The Delta strain spreads quicker than earlier strains. The evidence suggests that Delta immunity is eroding.
A 500,000-person study in South Africa by Johnson & Johnson on the COVID-19 vaccine has just been disclosed, which includes Delta variant cases.
The vaccine protects against death in 93 percent of cases and hospitalization in 71 percent of cases.
This appears to support the notion that those who have already received one dose of the Johnson & Johnson vaccination may desire a booster shot.
[Editor’s note: This response was developed from multiple Twitter threads suggested by Crotty.]
GOUNDER: Data from a clinical trial comparing low-dose against high-dose and single-dose versus two-dose regimens of the Johnson & Johnson vaccine should be available soon.
This information will be used to make recommendations regarding delivering further vaccine doses to persons who have already received one dose of the Johnson & Johnson vaccine.
Should we combine vaccines, such as an adenovirus vaccine from AstraZeneca or Johnson & Johnson with an mRNA vaccine?
CROTTY: It’s fairly evident that a follow-up dosage of mRNA is better than the second dose of AstraZeneca and also better than two mRNA doses for those who had viral vector vaccines [such as the AstraZeneca or Johnson & Johnson vaccines].
A heterologous prime-boost is a method of mixing vaccinations that have been used for [at least] 20 years.
The order is crucial. I would not invest in both Pfizer and J&J. However, you could have Pfizer and then a protein vaccine [a vaccination containing pieces of SARS-CoV-2 proteins, such as one developed by Novavax, which is not yet approved in the United States].
GOUNDER: More discussion on heterologous prime-boost is required: We could be on our way to an adenovirus vaccine followed by an mRNA or adenovirus vaccine followed by a protein vaccination.
Intranasal inhaled vaccinations should also be considered. Mucosal immunity [immunity in the nose and upper respiratory tract] would be better initiated with these.
Will a third injection have any negative consequences? And, if so, how serious are they likely to be?
GOUNDER: More of the same: moderate fever, achiness, and exhaustion.
But they aren’t going to be available to everyone.
Is it ethical to administer booster doses to people who have already been vaccinated while so much of the world remains unvaccinated?
CROTTY: It’s a false dichotomy, in my opinion.
You’re not going to shift the vaccines around since they’re about to expire. In the United States, the best-case situation would be if all unvaccinated persons were vaccinated. It’d be preferable to dealing with boosters. The math doesn’t even come close.
GOUNDER: It’s clear that simply giving individuals more doses has decreasing returns. By limiting community transmission [by vaccinating the unvaccinated], you may have a far greater impact.
How frequently will we require boosters? Will, there be just one, or will we need one every year, similar to the flu vaccine?
GOUNDER: I despise the term “booster” since it implies a yearly vaccination. The COVID vaccination reminds me a lot of the hepatitis B vaccine. We do not administer a hepatitis B vaccine every year.
It’s all about figuring out how many doses to give and at what intervals. I don’t believe it will be done every year. This virus, I believe, is on the verge of becoming endemic.
The goal is to turn this into an ordinary cold, rather than something that will put you in the hospital or kill you.
the author is :
Tanya Lewis is a senior editor at Scientific American who covers health and medicine.
Read More: https://mysteriousofscience.com/now-covid-19-has-hospitalised-over-100000-americans/