But in a news release, the Gamaleya Institute implied that its vaccine was superior to AstraZeneca’s. It said that the level of antibodies from vaccinated volunteers was “1.4-1.5 times higher than the level of antibodies of patients who had recovered from Covid-19.”
AstraZeneca, they claimed, only produced antibody levels equal to that in convalescent 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.
The Coronavirus Outbreak ›
Frequently Asked Questions
Updated September 4, 2020
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What are the symptoms of coronavirus?
- In the beginning, the coronavirus seemed like it was primarily a respiratory illness — many patients had fever and chills, were weak and tired, and coughed a lot, though some people don’t show many symptoms at all. Those who seemed sickest had pneumonia or acute respiratory distress syndrome and received supplemental oxygen. By now, doctors have identified many more symptoms and syndromes. In April, the C.D.C. added to the list of early signs sore throat, fever, chills and muscle aches. Gastrointestinal upset, such as diarrhea and nausea, has also been observed. Another telltale sign of infection may be a sudden, profound diminution of one’s sense of smell and taste. Teenagers and young adults in some cases have developed painful red and purple lesions on their fingers and toes — nicknamed “Covid toe” — but few other serious symptoms.
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Why is it safer to spend time together outside?
- Outdoor gatherings lower risk because wind disperses viral droplets, and sunlight can kill some of the virus. Open spaces prevent the virus from building up in concentrated amounts and being inhaled, which can happen when infected people exhale in a confined space for long stretches of time, said Dr. Julian W. Tang, a virologist at the University of Leicester.
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Why does standing six feet away from others help?
- The coronavirus spreads primarily through droplets from your mouth and nose, especially when you cough or sneeze. The C.D.C., one of the organizations using that measure, bases its recommendation of six feet on the idea that most large droplets that people expel when they cough or sneeze will fall to the ground within six feet. But six feet has never been a magic number that guarantees complete protection. Sneezes, for instance, can launch droplets a lot farther than six feet, according to a recent study. It’s a rule of thumb: You should be safest standing six feet apart outside, especially when it’s windy. But keep a mask on at all times, even when you think you’re far enough apart.
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I have antibodies. Am I now immune?
- As of right now, that seems likely, for at least several months. There have been frightening accounts of people suffering what seems to be a second bout of Covid-19. But experts say these patients may have a drawn-out course of infection, with the virus taking a slow toll weeks to months after initial exposure. People infected with the coronavirus typically produce immune molecules called antibodies, which are protective proteins made in response to an infection. These antibodies may last in the body only two to three months, which may seem worrisome, but that’s perfectly normal after an acute infection subsides, said Dr. Michael Mina, an immunologist at Harvard University. It may be possible to get the coronavirus again, but it’s highly unlikely that it would be possible in a short window of time from initial infection or make people sicker the second time.
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What are my rights if I am worried about going back to work?
- Employers have to provide a safe workplace with policies that protect everyone equally. And if one of your co-workers tests positive for the coronavirus, the C.D.C. has said that employers should tell their employees — without giving you the sick employee’s name — that they may have been exposed to the virus.
John Moore, a virologist at Weill Cornell Medicine in New York who was not involved in the study, said that it was too early to make any meaningful comparisons among the various Covid-19 vaccines. Each team uses different tests to measure antibody levels. And each group of recovered patients they study for convalescent plasma may have different levels of antibodies.
“We have long been suffering from the apples-versus-oranges scenario, but now we’re into fruit salad territory, and it drives me bananas trying to figure it all out,” he said.
One thing is clear, however: No Phase 1 / 2 trial can demonstrate protection against Covid-19.
That requires a so-called Phase 3 trial, in which a large number of volunteers are given either a vaccine or a placebo. A Phase 3 trial can also reveal harmful side effects missed by small preliminary studies.
In their paper, the Russian scientists wrote that they got approval on Aug. 26 to run a Phase 3 trial on 40,000 people. There are seven other vaccines currently in these late-stage trials. Johnson & Johnson is expected to start its own Phase 3 trial later this month, and Novavax is expected to start its own in October, bringing the total to 10.
Phase 3 trials can take months to yield clear results, Dr. Bar-Zeev said, and even then they have to be carefully reviewed before any decision is made about using a vaccine widely.
Source Article from https://www.nytimes.com/2020/09/04/health/russia-covid-vaccine.html
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