July 5, 2020
AliExpress WW
COVID vaccine race

COVID vaccine race

AliExpress WW
People train along a green road in Fayetteville, Ark., May 27, 2020. (Beth Hall / The New York Times)
People train along a green road in Fayetteville, Ark., May 27, 2020. (Beth Hall / The New York Times)

Judging by the comments I heard and read, many Americans expect that the COVID-19 vaccine will soon eliminate the need for masks and social distancing and allow us to renew our lives to COVID. As one of the neighbors said, referring to the administration’s Deformation Speed ​​program to bring the vaccine to the market, “I’ll start taking the subway and go to the office in the fall when we have the vaccine.”

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Alas, experts agree that such optimism is completely unrealistic. My neighbor — and the rest of us “non-essential” workers — will be lucky if we have access to a safe and effective vaccine in a year. That’s why

Doctors who are most knowledgeable about vaccine development and the real dangers of reckless rush warn that even though the promise of a vaccine may appear now or in a few months, premature release can do far more harm than good.

For example, as was shown, in 1955, when the original Salk polio vaccine was rapidly deployed, nothing came of the rush. Failure to mass produce the vaccine led to polio in 70,000 children, leaving 164 of them dead forever and 10 dead.

A coronavirus vaccine incident “can have unpleasant consequences, increasing people’s skepticism about vaccines and the development of vaccines and their distrust of doctors,” Dr. Brit Trogen told me.

“Everyone wants the vaccine to be a silver bullet that takes us out of this crisis, but strong political and social pressure to release the vaccine before science is ready can have devastating negative consequences,” said Trogen, a pediatrician living in NYU Langone Medical. Center and Bellevue Hospital in New York.

Keep in mind that if one or more of the vaccines currently being tested for COVID-19 can cause serious illness in even a very small percentage of people, there is still no effective cure.

Experts are also concerned about unfounded expectations efficiency vaccines. No vaccine prevents the disease in 100% of the recipients, although, as with the flu vaccine, vaccinated people may end up with a milder illness. Dr. Paul A. Offit, a global leader in vaccine development, said one of the tested COVID vaccines is likely to prevent many more serious and life-threatening infections.

“Even a vaccine that is 50% effective in preventing fatal diseases can be acceptable,” said Offit, professor of pediatrics and director of the Vaccine Training Center at the Philadelphia Children’s Hospital.

It is not enough to know that the candidate vaccine causes sensitivity to antibodies – even vigorous – in susceptible people or that hundreds of volunteers vaccinated with it do not experience serious side effects. Until the vaccine is tested on tens of thousands of people, doctors cannot be sure that it is safe and effective, and sometimes even then.

Under normal conditions, this process takes years. But this is not a normal time, so testing for potential COVID-19 vaccines has been delayed for months, which may increase the risk of complications. However, Dr. Francis Collins, director of the National Institutes of Health, pledged that, despite the rush to get an effective vaccine for the public, “we will not compromise on safety.”

Here is how Offit, who is involved in monitoring COVID vaccine trials, described the necessary sequence of events:

A promising vaccine is first tested on laboratory animals that typically become infected with COVID-19 when infected with a virus, such as mice, to see if it prevents the disease. This is called “proof of concept” that the vaccine can work. It is followed by phases I and II, possibly in hundreds or thousands of human volunteers. Researchers are looking for evidence that the vaccine is safe, and testing different doses of the vaccine to find the one that best produces antibodies that can protect against the virus. At least two vaccine candidates are already at this stage.

A big test is underway, Phase III, a prospective, placebo-controlled study of tens of thousands of people to evaluate safety and efficacy. This phase is expected to begin in July for one or more of the five promising candidates for COVID vaccines. Each phase III trial will include 20,000 people who receive the experimental vaccine, and a control (placebo) group of 10,000 unvaccinated people. Tests will be conducted in regions and abroad that are already or are expected to become “hot spots” for COVID infections.

But depending on how widespread the virus is this summer, when the tests are conducted, it may take months — or even a year — to determine how well the vaccine prevents the disease.

“This is the only way to find out if the immune response protects in the real world in previous trials,” Offit said. “If there are few diseases in the summer, this can be a problem. We may need to continue to recruit participants until enough people in the placebo group get sick to make a meaningful comparison with the vaccinated group. We cannot close the process. ”

He expects the vaccine to be at least 70% effective so that it can be used for mass use. But even then, he added, “we would not know for many months how long the immunity would last.” He cautioned against being overly optimistic about how good an approved vaccine would be. He said that a vaccine can be considered acceptable if it prevents a serious illness, but not most or all of the infections that do not cause symptoms or only a mild illness.

“Science is humiliating – it always brings surprises that we cannot expect,” he said. “Once we get the vaccine, our work will drive expectations. “We will learn about safety as soon as millions of people receive the vaccine, and we will learn about longevity only with time.”

Meanwhile, according to the government’s Operation Warp Speed, factories are currently preparing to produce tens of millions of doses of the most promising vaccines, so if and when one or two are approved as safe and effective enough, enough vaccine can be brought out. without further delay for those most at risk.

This approach was used when the Salk vaccine was developed in the early 1950s, and the developers of the COVID vaccine will be on their guard to avoid a similar error caused by rush.

The first doses of the approved COVID vaccine will be sent to healthcare workers, residents and long-term care staff, and then to key government officials such as police, firefighters and transit workers, as well as food workers. Until hundreds of millions of doses are available — sometime in 2021, if all goes well — the vaccine will be offered to the general public.

Two doses of the vaccine are expected to provide adequate protection against COVID-19. Thus, if the whole country were to be immunized, more than 600 million doses of the vaccine would have to be produced.

This article originally appeared in New York Times,

© 2020 The New York Times Company


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