Friday, a team of Russian scientists Published The first report on their Kovid-19 vaccine was severely criticized last month by President Vladimir Putin for approving it before clinical trials could be proven safe and effective.
Among a small group of volunteers, scientists have found that this vaccine produces modest antibodies against coronavirus, while causing only mild side effects. Research has not yet shown whether vaccinated individuals are more likely to become infected than those who are not.
In August, Mr. Putin Announced Vaccine – with great affection for the so-called Sputnik v – To be approved “works efficiently enough”. He declared its approval “a very important step for our country, and for the whole world in general.”
But vaccine developers Denied Observed decision that no data were published on the vaccine. In addition, critics point out that Russian scientists have not yet conducted a large trial on tens of thousands of people, who need to prove that the vaccine works.
The new paper, published in The Lancet, contains the first batch of public data from Sputnik V’s clinical trials. Independent scientists were impressed by the rigor of this work.
Nour Bar-Jeev of the Johns Hopkins Bloomberg School of Public Health said: “Science seems to have done it honestly. Commentary On new paper. However, he warned that no one would know if Sputnik V was safe and effective until the big trials were over.
“If the Russian vaccine is successful we should welcome it, and if other vaccines are successful we should welcome them,” Dr. Bar-Jeev said. “But all must be assessed equally rigorously.”
Researchers at the Gamaleya Research Institute in Moscow used a design for a vaccine they had previously developed and tested for another coronavirus-causing disease called MERS.
The Sputnik V vaccine stimulates the immune system to attach to a person’s cells to make the protein commonly found in the coronavirus that causes Kovid-19. The researchers transmitted the gene for this viral protein to a second virus called adenovirus.
When injected into the hand, the adenovirus slips into the muscle cells. It is genetically engineered so that it does not make copies of itself or cause illness. But once it sends the coronavirus gene into a cell, the cell begins to make protein.
Similar adenovirus-based vaccines Are also being tested By AstraZeneca, Consinobio and many other teams including Johnson & Johnson.
Each team is testing a different strain of adenovirus. Unlike everything else, the Russian team is combining two adenoviruses into one vaccine. For their initial clinical trial, Gamaliya researchers gave volunteers an initial shot of an adenovirus called Ad26, and then, three weeks later, a shot called Ad5.
In the Lancet paper, the researchers said they tested the vaccine on hamsters and monkeys. They claim to have protected animals from coronavirus without any harmful side effects, but have not submitted any data about these studies in their new paper.
The trial phase they conducted on human volunteers is called the 1/2 trial. This is small: only 40 volunteers with both types of adenovirus received the full vaccine. No one got a placebo.
In comparison, the Chinese company Consinobio a Step 1/2 Trial Of these, 382 were vaccinated and another 126 were given placebo.
The Russian vaccine has produced mild symptoms in many cases, the most common of which are fevers and headaches. Other adenovirus-based vaccines have produced similar side effects.
“I hope you have some symptoms – it’s normal,” Dr. Bar-Jeev said.
Researchers have found that volunteers who receive the full vaccine produce antibodies that can prevent the virus from replicating in cells.
To assess the effectiveness of their vaccine, Russian researchers compared the level of antibodies with samples taken from people recovering from Kovid-19’s natural infections. Convalescent plasma, as these models are known, contains antibodies to the virus that people make themselves.
In the paper, researchers said that vaccinated people had levels of antibodies found in circulating plasma.
The vaccine produces “good antibody levels in all volunteers,” said Akiko Ivasaki, an immunologist at Yale University who did not participate in the study.
But one News release, The Gamalaya Institute suggests that its vaccine is superior to estrogenica. The level of antibodies from vaccinated volunteers was “1.4-1.5 times higher than the level of antibodies in patients recovering from Kovid-19”.
AstraZeneca, however, produced only antibody levels similar to those in plasma.
It is not clear why the paper presents a different picture. The authors of the study did not respond to a request for comment.
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Frequently Asked Questions
Updated September 4, 2020
What are the symptoms of coronavirus?
- Initially, the coronavirus It mainly seemed to be a respiratory illness – Most patients have a fever and chills, are weak and tired, and many are, although some do not show many symptoms. Those who appeared ill had pneumonia or acute respiratory distress syndrome and received supplemental oxygen. So far, doctors have identified more symptoms and syndromes. In April, The CDC has been added to the list of startup codes Sore throat, fever, chills and muscle aches. Gastrointestinal upset such as diarrhea and nausea were also observed. Another telltale sign of infection may be a sudden, one’s deep decline Sense of smell and taste. Teenagers and young adults have sometimes developed painful red and ple da lesions on their fingers and toes – nicknamed the “Kovid toe” – but with some other serious symptoms.
Why is it safe to spend time together outside?
- Public meetings Low risk because air disperses viral droplets and sunlight kills some viruses. Open spaces prevent the virus from building up and absorbing concentrated amounts, which can occur when infected people inhale hale for a long time in a confined space, says Dr. Julian W., a virologist at the University of Leicester. Tang said.
Why does standing six feet away from others help?
- Coronavirus is spread mainly through droplets coming from your mouth and nose, especially when you cough or sneeze. CDC, one of the companies that uses that measure, Has a six-foot recommendation With the idea that very large droplets that people expel when they cough or sneeze fall to the ground within six feet. But six feet is not the magic number that guarantees complete protection. For example, sneezes can inflict droplets farther than six feet, According to a recent study. This is the rule: you must stand safely at a distance of six feet, especially when it is windy. Even if you think you are too far away, always wear a mask.
I have antibodies. Am I immune now?
- Currently, Possibly at least several months. There are horrific accounts of people suffering from what appeared to be Kovid-19’s second match. But experts say these patients may have a draw-out course of infection, which can slowly take weeks to months after initial exposure to the virus. People infected with coronavirus usually Production Immune molecules called antibodies Protective proteins made in response to infection. These may be antibodies The last in the body Only two to three months, It may seem worrying, but it is more common after a severe infection has subsided, said Dr. Michael Mina, an immunologist at Harvard University. It is possible to get coronavirus again, but it is unlikely to be possible in the short time from the initial infection or make people sick for a second time.
What are my rights if I am worried about going back to work?
John Moore, a virologist at Veil Cornell Medicine in New York, who did not participate in the study, said it was too early to make any meaningful comparisons between the various Kovid-19 vaccines. Each team uses different tests to measure antibody levels. And in each group of recovered patients they are studied for recovered plasma.
“We’ve been suffering from the apple-versus-orange scene for a long time, but now we’re in the fruit salad territory, and it tries to figure out all of the bananas,” he said.
One thing is clear: however, the Phase 1/2 trial does not demonstrate protection from Kovid-19.
This requires a so-called Phase 3 trial, in which a large number of volunteers are vaccinated or placebo. Stage 3 trials also reveal harmful side effects that small preliminary studies have missed.
Russian scientists wrote in their paper that they had received permission on August 26 to conduct a third phase trial on 40,000 people. There are Seven Other vaccines currently in the final stages of trials. Johnson & Johnson is set to launch its own Phase 3 trial later this month, with Novavox expected to launch on its own in October, reaching a total of 10.
Stage 3 trials can take months to give clear results, Dr. Bar-Jeev said, adding that they should be carefully considered before making any decision about the widespread use of the vaccine.
“Yes, we all want the vaccine, but we don’t want to go wrong,” he said. “So stay there and wait, so we know what we’re doing.”
Andrew Kramer contributed to the reporting from Moscow.