new mutation accelerated the spread of the Corona virus
new mutation accelerated the spread of the Corona virus
The virus that causes COVID-19 is not the same strain that first appeared from China. A new study shows that it has changed little in a way that makes it more contagious to humans.
Compared to the original strain, people infected with the new strain - called 614G - had higher viral loads in their noses and throat, although it did not appear to develop any disease. But it is more contagious to others.
"That kind of makes sense," says Ralph Barrick, Ph.D., professor of epidemiology, microbiology and immunology at the University of North Carolina at Chapel Hill.
The new strain has a change in its prickly protein - the regions of its outer shell that stick to our cells and infect them. Change makes it a more efficient predator. It moves quickly from cell to cell in our bodies, and mimics itself at a rapid pace.
Baric's experiments help explain why the 614G strain, which first appeared in Europe in February, is so prevalent so rapidly.
He says the virus likely jumped from bats and discovered an entirely new group of human hosts, with more than 7 billion of us on the planet infected. None of us have any immune defenses against it, so we are prime targets. Viruses with genetic advantages that help them replicate themselves faster and jump more quickly between hosts are the copies that will survive and be transmitted.
Barrick, who is one of the most prominent Corona virus experts in the world, says: "So it could jump from one person to another, and this virus will be the most competitive in terms of preserving the virus." His new study has been published in the journal Science.
The new study supports previous research by a team of scientists led by Pete Corper, Ph.D., at Los Alamos National Laboratory in New Mexico. The team first noticed the rapid spread of the new strain and questioned whether the virus was not evolving to become more easily transmissible between people.
In the new experiments, animals infected with the new strain of 614G transferred it more quickly to healthy animals than those infected with the original strain.
Researchers at the University of Wisconsin in Madison infected 16 hamsters with SARS-CoV-2. Eight hamsters were infected with the new 614G strain. Eight others were infected with the original strain that was first identified in China. Each affected hamster was paired with a healthy hamster that was separated by a section in a cage, so that the animals could not touch the same air but breathe in. By the second day of the experiment, five of the eight healthy hamsters who shared air with the 614G-infected animals became ill and released the virus themselves, but none of the healthy hamsters associated with the original strain became ill. . The original strain eventually infected healthy animals, but it took another two days for that to happen, proving that the changes helped speed the spread of the virus.
Barrick and his team also questioned whether changes in the virus's structure would affect how future treatments - including a vaccine - would work against it, as all treatments currently in development are designed to counteract the original strain that originated from the virus. China.
They tested antibodies extracted from the blood of people who survived COVID-19 infection on the new and old strains, and found no statistically significant difference in how well these antibodies neutralized the virus.
This is good news, as it means that people who recover from infection with the original strain may have some protection against the new strain.
In the United States, the original strain was imported from China and started spreading on the West Coast, while the new strain was imported from Europeans who were mainly traveling to New York and the rest of the East Coast.
Aparic and his team have also tested the antibodies that are being developed as treatments to give people negative immunity to the virus. These seem to work well, too.
"The vaccines, which are all based on the original Chinese strain, provide a good immune response that protects against this strain, so this is good news," he says.
While current treatments and prevention efforts do not appear to be affected much by this change in the virus, the mutation raises questions about how quickly new strains will emerge and whether or not one of these strains might cause a problem in the future, Barrick says.
Coronaviruses, as a group, are very stable. They have a special molecule - really called a proofreader - that ensures the virus is replicated correctly.
Because of this proofreader, the rapid emergence of these new strains of the new coronavirus was somewhat surprising to the scientists who studied them.
One of the developments Barrick and other scientists are watching closely is the emergence of new strains found on mink farms in Denmark and the Netherlands that have been shown to infect humans.
There is work being done to ensure that at least one of these strains - the so-called group 5 virus - may have developed enough changes in its spiky proteins to help it escape the vaccine.
Barrick says the research needs to be verified, but early work suggests the virus has apparently changed to help it infect mink animals more efficiently, while also preserving its ability to infect humans.
When the virus develops in a way that allows it to spread into an animal species, "eliminating this virus becomes more difficult," he says.
If the virus continues to be transmitted in mink animals, and if we vaccinate everyone in Denmark, but leave mink, Barrick says, the virus will remain suspended until there are enough new hosts exposed to infection - usually young children - and then jump back into humans.
For this reason, he says mink farms may need to take more steps, such as vaccinating their animals, or at worst killing mink, to control its spread.