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2. The immune response is strong
Scientists testing the effectiveness of vaccines often have the ability to block the ability to infect antibodies and virus cells. In laboratory experiments, they mix the blood of people who have been infected or inserted with cells into a plate to see if blood antibodies can “neutralize” the virus. These experiments are easy to perform. But antibodies are “a very narrow part of what the immune response can be,” says epidemiologist and demographer at Oxford University Jennifer Dowd.
Immune cells called T cells also help keep infections under control. These cells cannot neutralize the virus, but they can search for and destroy infected cells. It helps protect against serious diseases. Data from people who have had Covid-19 suggest that T cell responses should provide broad protection against most SARS-CoV-2 variants.
3. When infected people are infected, the shots protect them against the worst results
The vaccine that can block the infection is wonderful. But “the most important thing is to keep people out of the hospital and out of the ground,” Friedrich says. And there is evidence that current vaccines do just that. In South Africa, a dose of Johnson & Johnson vaccine It has 85% support against covid-19-related hospitalizations and deaths. At that time, 95% of cases were caused by variant B.1,351. Israel, where B.1.1.7 became the main strain, two doses of Pfizer were offered 97% protection against symptom-related hospitalizations of kobid-19 and covid-19.
4. The same mutations appear
Once the virus enters a cell, it begins to recur. The more copies you make, the more likely it is that random errors or mutations will occur. Most of these copying errors are irrelevant. A handful, however, can turn the virus around. For example, an extreme protein mutation known as D614G helps transmit SARS-CoV-2. Another, E484K, may help prevent the body’s antibody response. If viruses with these advantageous mutations are transmitted from one person to another, they may begin to overcome viruses that do not have them, a process called natural selection. Thus, the more transmitted variant B.1.1.7 became the main US strain.
In the case of SARS-CoV-2, mutations that enhance the virus appear in various parts of the world, a phenomenon known as convergent evolution. “We’re seeing the same combinations evolving over and over again,” says Vaughn Cooper, an evolutionary biologist at the University of Pittsburgh. Imagine a Tetris game, writes Cooper The latest story in Scientific American magazine. “A limited number of building blocks can be assembled in different ways, in different combinations, to achieve the same winning structures.”
Cooper and several other researchers see this as promising evidence of convergent evolution: new ways of adapting the virus to the current environment may be depleted. “It’s a small deck of cards right now,” he says. “If we control infections, there will be a small deck of cards left.”
5. If the effectiveness of the vaccines starts to decrease, we can do booster shots.
In the end, current vaccines will not be as effective. “That’s to be expected,” Chandran says. But he hopes that will happen gradually: “It will be time for the next generation of vaccines.” Modern has already begun testing the effectiveness of a protective shotgun against B.1.351 (first identified in South Africa). Company last week he released the initial results. A third dose of the current covid-19 shot or a B.1.351-specific booster increased protection against variants first identified in South Africa and Brazil. But the new innovative specific variant elicited a greater immune response against B.1.351 than the third dose of the original shot.
This has been alleviated for a couple of reasons. First, it shows that promoters of specific variants can work. “I believe the feasibility of producing these RNA-based vaccines is an achievement in our lives,” says Cooper.
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