Coronavirus vaccine manufacturers are learning how to modify their vaccines to deal with viruses changes. Experts are looking at flu vaccines, or flu, to help them understand whether and when the scenes may change.
Richard Webby manages the World Health Organization (WHO) flu center from St. Louis Children’s Research Hospital. Jude in Virginia. He said the process would not happen quickly.
“It’s not something you can sort flip on switch, do it overnight, ”said Webby.
Viruses often suppress, or change. Recent studies have raised concerns that first-generation COVID-19 vaccines are not as effective against coronavirus mutation that first appeared in South Africa. However, many of the COVID-19 vaccines are made with new technology that allows modifications. But it will still be difficult for experts to decide if the virus has moved enough to make it necessary to change the vaccines.
The flu offers a model
The WHO and the U.S. Food and Drug Administration (FDA) are looking to the flu vaccine system worldwide for help. The flu moves much faster than the coronavirus. Scenes of flu need to change almost every year.
National centers around the world collect flu viruses and monitor their evolution over time. They plant samples to dedicated WHO laboratories for advanced “antigenic” testing to determine vaccine potency. WHO experts and government regulators work together to agree the new vaccine each year recipe. Manufacturers then make the necessary adjustments.
For COVID-19 vaccines, Webby said setting up a similar observation and testing network will be an important step. It can then decide which mutations are of most concern. Today, there are wide differences in how countries are rian and test mutated versions. For example, Britain is doing more testing on the variable virus genome what the United States is doing.
Three variables they are first discovered in anxious Britain, South Africa and Brazil due to a combination of mutations that are making them spread easier and faster.
On Sunday, U.S. researchers reported another mutation found in seven mutations that have emerged in several U.S. states. Researchers still do not know if this mutation makes the virus easier to spread.
COVID-19 vaccines and routine modifications
Just because a variety spreads more easily does not mean it is against vaccines. But the variability first identified in South Africa raises concerns.
David Ho from Columbia University sent blood samples from people who received the Pfizer or Moderna vaccines in small containers with the mutated virus. He found that vaccinated antibodies still offered protection, but the protection was not as strong.
Early test results of two other vaccine candidates – from Novavax and Johnson & Johnson – supported Ho’s conclusions. Both were still offering protection. However, that protection was weaker in South Africa than elsewhere. A much smaller trial of the AstraZeneca vaccine in South Africa has raised questions about its effectiveness.
Several of the COVID-19 vaccines require approval and are available in two doses for full effectiveness. The drug dealer Moderna is about to explore one possible solution: Could the third look of his vaccine build enough immunity to fight off some changes?
Ho said it’s a good idea to experiment, as people may still have “enough cuisean”If their antibody levels are very high.
Changing the recipe
Leading manufacturers are also developing experimental variable vaccines as an additional measure.
COVID-19 vaccines produce antibodies that recognize the spike proteins covering the coronavirus. As the virus moves, the spike protein is sometimes altered in ways that make it more difficult for vaccine-produced antibodies to be identified.
The Pfizer and Moderna vaccines are produced by a piece of genetic information called messenger RNA (mRNA). It tells the body how to make harmless copies of the spike protein that trains cells that fight disease. To modify the vaccine, the drug dealers can modify the first version of genetic information with mRNA for the mutated spike protein.
The AstraZeneca vaccine and the Johnson & Johnson vaccine are expected to be available in the United States soon. Both are made with cold viruses engineered to inject a spike protein gene into the body. Making changes to these two vaccines requires cold viruses with the mutated gene. The process is a bit more complicated than the mRNA process. But reproducing traditional flu shots is still not as difficult.
Testing vaccines, about two
First-generation COVID-19 vaccines have been tested in tens of thousands of people to make sure they work and are safe. The investigation took several months.
By changing the recipe to better virus mutations, there will be no need to repeat these studies in thousands of people, Dr. Peter Marks said. He is the head of vaccination with the FDA. He recently told the American Medical Association that the FDA intends to be “extremely flexible” when it comes to approving vaccine modifications. In other words, it works quickly.
If an updated vaccine is needed, he said, tests in a few hundred people would tend to know whether it causes a good immune response.
My name is Ashley Thompson. And I’m Iain Russell.
Lauran Neergaard told the Associated Press this story. Ashley Thompson changed it for VOA Learning English. It was Mario Ritter, Jr. the editor.
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Words in this story
mutation –N. changes in plant or animal genes that cause different quality
flip on switch –Idiom to make change easily and quickly
sample –N. a bit of something that is used to convey information about what has been taken from it
recipe –N. a set of instructions for making food
rian –V. follow and observe, especially in an attempt to find evidence
genome –N. the total amount of genetic information in organic chromosomes
variable –N. something that is different in some way from others of the same kind
cuisean –N. something more that could reduce side effects or complications
spike –N. a thin pointed structure that protrudes from something