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The myth of “good Covid vaccines” and “bad Covid vaccines”

fr24news– Mike Ryan, the director of health emergencies for the World Health Organization, recently had a conversation with his mother, the kind of conversation many public health professionals have these days, much to their dismay. Ryan’s mother was concerned about one of the Covid-19 vaccines used in Ireland, where she lives. The one manufactured by AstraZeneca.
Clinical trials had shown that the vaccine offered protection against the disease, but less than the vaccine made by Moderna or the one made by Pfizer and BioNTech. Ryan’s mother feared the vaccine was not good enough.

Ryan, who never mince words, decided it was time to chat with his 80-year-old mother. “Whatever vaccine they come up with, take it,” he told her. “Because it’s the best decision you can make that day for your health.”


It’s a message Ryan and other public health officials are trying to get across to everyone – but it’s not necessarily a message that’s well received. Media coverage and social media posts about clinical trial results create a hierarchy of Covid vaccines in the minds of much of the public: ‘good vaccines’ and ‘bad vaccines’. The first one you might try to find; the latter might even get you out of the line.

This, say health officials, is a problem.


The problem isn’t just that people are getting picky about the vaccine they want, slowing down the task of inoculating enough people to lessen the impact of Covid-19. Public health experts are also concerned that a simplified account overlooks the essential facts – let’s say the vaccines from AstraZeneca and Johnson & Johnson were tested in clinical trials after variants of the SARS-CoV-2 virus began to appear. circulate widely, probably reducing their effectiveness more than the virus did. cases with the Pfizer and Moderna vaccines, the first to be cleared.

Vaccines perceived to be less effective are also found to be those that may be the best option in rural America or in low-income countries, as they do not require the ultra-cold freezers and complex delivery systems that one finds. usually found in or near major cities. .

“I was worried that we would have that kind of, ‘Oh, is this Moderna? Awesome! Is this [Johnson & Johnson]? No, thank you, I’ll wait, ”said Alison Buttenheim, associate professor of nursing and health policy at the University of Pennsylvania, whose research focuses on vaccine acceptance. “It’s just going to delay getting the coverage we want to get. ”

In truth, the phenomenon is already playing out, even among some who understand the caveats around when studies were conducted and the operational benefits of these easier-to-deploy vaccines. STAT asked Emory University immunologist Rafi Ahmed if he would indicate a preference if his mother asked him for advice on Covid vaccines. Ahmed replied without hesitation: He would tell him to get one of the messenger RNA, or mRNA, vaccines made by Pfizer or Moderna. “It’s human nature,” he insisted. “It is common sense.”

Experts say this problem is likely to worsen with the clearance of more vaccines, each with varying efficacy, dosing schedules (one dose or two) and dose intervals (21 days, 28 days, up to to 12 weeks in some cases and places). . They also say there are only limited messaging strategies to address this.

“I think right now the message really needs to be that vaccines that are allowed to be used are allowed, because they will provide significant protection against Covid-19 disease. And if you are not vaccinated, you have no protection against Covid-19 disease, ”said Glen Nowak, director of the Center for Health and Risk Communication at Grady College of Journalism and Mass Communication in Athens, Georgia.

Kasisomayajula “Vish” Viswanath, professor of health communication at Harvard TH Chan School of Public Health, said he was deeply concerned that decisions about where to use some of the vaccines that appear to be less effective will be considered. through a racial or socio-economic prism, even though the reasons for offering these vaccines in certain settings make sense from a public health perspective and get the vaccine to those places more quickly.

“It’s going to explode in the near future, I think,” Viswanath warned.

This is not a problem the public health folks anticipated. Hardly anyone, after all, expected Pfizer and Moderna, the first vaccine makers to produce clinical trial results, to report such astonishing efficacy data, at around 95%. Seasoned vaccine researchers – with decades of experience in the often frustrating field of vaccine development – laughed gleefully when talking about mRNA vaccines.

For a brief heady period, it seemed the gods had taken pity on mankind. The Food and Drug Administration quickly issued emergency use authorizations for both vaccines. Experts, including Anthony Fauci, the country’s chief vaccine officer, predicted that several vaccines would be almost certain to be effective because they targeted the same protein on the SARS-2 virus.

Then reality set in. The first data on the AstraZeneca vaccine, released in late November, suggested that the protection induced by the British-made vaccine was more moderate, at around 62%, depending on the interval between doses.

More recently, clinical trials of two other vaccines have produced results – the Novavax recombinant protein vaccine, based on tests in Britain and South Africa, and the breakthrough potential of Johnson & Johnson, a single dose vaccine .

The Novavax vaccine was around 90% effective, except in South Africa, where, faced with a widely used variant, it was around 60% effective. The effectiveness of the J&J vaccine was 66%, although this also varied a bit by geography.

If the results of the trials of these vaccines had been the first to be published, the world would have burst champagne corks. But as the data came after the overwhelmingly positive results from Pfizer and Moderna, the enthusiasm was dampened.

Anna Durbin, a vaccine researcher at the Johns Hopkins Bloomberg School of Public Health, noted that most trials have focused on the ability of vaccines to prevent symptomatic infection – and by that measure, there are some differences between vaccines.

But Durbin, who runs one of the sites for the US AstraZeneca trial, said most infections found in clinical trials are so mild that they are only noticed because the trial volunteers are watched so closely. A report of a sore throat may lead to a Covid test; if it is positive, it is. Based on this measurement, the differences between vaccines might not be as significant.

Durbin stressed that what the world needs are vaccines to prevent serious illness, hospitalizations and deaths from Covid. On this front, all the vaccines tested so far appear to be quite effective.

“I believe that in all the clinical trials that have been done so far, with the seven or eight candidates that we know of, there has been no case of death or serious illness with hospitalization that has occurred in the vaccinated group,” whatever vaccine, ”WHO chief scientist Soumya Swaminathan told a press conference last week. “So I think it’s clear that it protects against serious illness.”

This point, however, gets lost in conversations about vaccines among ordinary people. The same goes for the fact that AstraZeneca, Novavax, and J&J vaccines are less expensive than mRNA vaccines, making them more affordable in developing countries.

The J&J vaccine has another advantage in that it is given in a single dose, which would make vaccinating the homeless much less complicated, not to mention people who might otherwise find it difficult to take time off work for their own sake. vaccinate in two doses.

The J&J vaccine will likely be the third to be authorized in the United States; The FDA advisory committee is meeting to review it on February 26, and it is widely expected to be cleared by the agency for emergency use within days.

This is where the messaging challenge is likely to become more difficult, experts say.

“For me, one of the trickier things about it is that we’re probably going to end up with a vaccine – the J&J – that shows a little less effectiveness than those first two amazing ones that came out the door and that is also most suitable for rural areas. settings, low resource settings, settings without very good freezers, ”said Buttenheim.

“And while that would be great… to say, ‘Let’s use J&J in contexts where it will be most feasible and appropriate,’ once you see it as the worst performing vaccine, then it’s like, ‘Great, send it. the [expletive] vaccine for the poor, ”she said. “There is no easy solution to this. I think from a behavioral science perspective, the fact that we’re basing ourselves on these vaccines that are 95% effective is difficult.

The deployment of the J&J vaccine will be a harbinger of bigger problems to come, worries Viswanath.

“If some groups in the system get certain types of vaccines with differential efficacy, all hell will break out,” he warned.

Black and Latin Americans have suffered disproportionately higher infection rates during the pandemic and are getting vaccinated at lower rates so far than white Americans. “If there is some kind of differential allocation, even if the reasons are good, it will certainly explode into allegations of racism and mistrust,” Viswanath said. “We already have a lot of mistrust in the system.”

To avoid this, public health officials will need to be clear about what vaccine is being used, where and why, Viswanath said. Nowak agreed: “I think transparency will be essential. Honesty will be essential. ”

“The message that what we do is driven by the desire to get as many people vaccinated and protected as quickly as possible against Covid-19 disease is the underlying motivation,” Nowak said.

Ryan, the WHO official, thinks being able and willing to show that the vaccine is allocated through a process based on operational needs will help.

“People don’t like that it’s black box decision making,” he said. “Because then they can add the conspiracy theory to it. “Ah, you see, the reason they do this is that they don’t like people in rural areas. And I can imagine how that could play out in the United States

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