Top Scientists Question Need For Covid Booster Injections – fr

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Top Scientists Question Need For Covid Booster Injections – fr


COVID-19 vaccine developers are increasingly claiming that the world will need annual booster vaccines or new vaccines to fight the coronavirus variants, but some scientists are wondering when or if such vaccines will be needed.

In interviews with Reuters, more than a dozen influential infectious disease and vaccine development experts said there was growing evidence that a first round of global vaccinations could offer protection. lasting against the coronavirus and its most disturbing variants discovered to date.

Some of these scientists have expressed concern that public expectations for COVID-19 boosters are being set by pharmaceutical executives rather than health experts, although many agreed it was prudent to follow suit. prepare for such a need as a precaution.

They fear that a push by rich countries for repeated vaccination starting this year could widen the gap with poorer countries which struggle to buy vaccines and may take years to immunize their citizens, if only ‘just once.

“WE ARE NOT SEEING THE DATA YET”

“We do not yet see the data that would inform a decision on whether or not booster doses are necessary,” said Kate O’Brien, director of the Department of Immunization, Vaccines and Biologics at the World Health Organization. health (WHO).

O’Brien said the WHO is forming an expert group to assess all data on vaccine variants and effectiveness and recommend changes to vaccination programs if necessary.

Pfizer Inc CEO Albert Bourla said people would “likely” need a booster dose of the company’s vaccine every 12 months – similar to an annual flu shot – to maintain high levels of immunity against the original SARS-CoV-2 virus and its variants.

« ZERO PREUVE »

“There is no evidence, and I mean zero, to suggest that this is the case,” retorted Dr. Tom Frieden, former director of the US Centers for Disease Control and Prevention.

“It is totally inappropriate to say that we will probably need an annual booster because we have no idea how likely it is to happen,” said Frieden, who now heads the global public health initiative. Resolve to Save Lives, on Pfizer’s claims about boosters.

Pfizer, responding to criticism, said it expects a need for boosters while the virus is still circulating widely. That could change once the pandemic is more firmly under control, a spokesperson for the company said.

Moderna Inc CEO Stephane Bancel aims to produce a vaccine by fall that targets a variant first identified in South Africa and expects regular boosters to be needed. The United States is preparing to have such doses on hand for Americans, while the European Union, Britain and Israel have ordered new supplies of COVID-19 vaccines to be rolled out as protective boosters.

PLANNING AHEAD

Some health experts, including Richard Hatchett, chief executive of the Coalition for Epidemic Preparedness Innovations (CEPI) which has funded numerous vaccine projects, say vaccine makers are right to plan in advance for recalls given the ‘uncertainty about what will be needed in the long run.

Governments can then decide for themselves whether or not to buy the products, he said.

Pfizer and its German partner BioNTech SE have so far found that their injection remains over 91% effective for six months after people have received their second dose, compared to nearly 95% shown in their clinical trial. Businesses will monitor the robustness of the protection over time.

Dr William Gruber, senior vice president of clinical vaccine research and development at Pfizer, told Reuters earlier this month that the forecast for annual boosters was based on “little evidence” of a decline. immunity during those six months.

MAJOR TURNOVER

Pfizer expects the COVID-19 vaccine to be a major contributor to revenue for years to come and has forecast sales of $ 26 billion from the shot in 2021. Global spending on COVID-19 vaccines and recalls could total $ 157 billion through 2025, according to US Health data company IQVIA Holdings.

Moderna President Stephen Hoge expects boosters to be needed to keep immunity levels high, in part due to reluctance to get vaccinated, as around 30% of the U.S. population may not agree to be vaccinated. As long as the virus is circulating widely, people at high risk for serious illness may need to boost their immune protection, Hoge said.

“All governments are in discussions with (Moderna) and other companies about boosters,” he said.

At the end of last year, scientists were optimistic that highly effective vaccines could quickly curb the global pandemic that has hit economies and killed more than 3.4 million people.

Those hopes faded in February with evidence that mutant versions of the virus could escape the protection offered by vaccines.

Laboratory studies have shown that the South African variant can produce six to eight-fold reductions in antibody levels in people vaccinated with Pfizer or Moderna vaccines.

File photo: A man walks past newspaper billboards during the coronavirus (COVID-19) outbreak in Johannesburg, South Africa

Data from clinical trials also showed that the vaccines from AstraZeneca Plc, Johnson & Johnson and Novavax Inc were less effective in preventing infections in South Africa, where the variant is widespread.

These studies prompted pharmaceutical companies to start testing booster doses of their vaccines and to develop injections targeting specific variants of the virus.

“CUSHION EFFECT”

However, more recent research suggests that Moderna and Pfizer / BioNTech vaccines produce high levels of protective antibodies to create a “cushion effect” against known variants, said Dr Anthony Fauci, director of the National Institutes of Allergy and Infectious. Diseases (NIAID) and a senior White House adviser.

And the antibodies – which prevent the coronavirus from attaching to human cells – don’t tell the whole story.

Several studies suggest that T cells – a type of white blood cell that can target and destroy already infected cells – can help prevent severe COVID-19 and hospitalization.

NIAID researchers found that T cells in the blood of people who recovered from the original virus could still fight infections caused by the disturbing variants found in the UK, South Africa and Brazil.

“It is entirely possible” that boosters are not needed, Fauci told Reuters.

« A REALLY GOOD VACCINE ”

“It is conceivable that the variants are not as much of a problem with a very good vaccine as we might have anticipated.”

Nonetheless, health authorities in the United States, Britain and Europe are reassuring their populations that a new set of vaccines will be available if needed, with many countries still desperate for vaccine supplies.

“It is a huge concern that … rich countries are starting to give booster doses and further restrict the supply of the first dose of vaccine to people,” said Rajeev Venkayya, global vaccine manager for Takeda Pharmaceutical Co. Dr Monica Gandhi, an infectious disease physician at the University of California, San Francisco, said that ultimately decisions about whether or not to need boosters will be best made by public health experts, rather than by the CEOs of a company that could benefit financially.

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