Vaccination does not appear to lead to more dangerous corona variants

A study conducted in Hong Kong showed that vaccines do not induce the coronavirus to evolve into a variant that escapes those vaccinated against.

It sounds like a reasonable concern: If you vaccinate everyone against the coronavirus, wouldn’t you create a new variant that is immune to the vaccine in question? And then you have to come up with a new vaccine, and history repeats itself.

Fortunately, this concern appears to be unfounded. large study in hong kong, Published in Nature Communicationsshows that both the Chinese Pfizer and Sinovac vaccines do not lead to a more dangerous type of corona.

Well captured

For the study, samples of SARS-CoV-2, as the coronavirus is still officially called, were collected from 2,820 different patients. “This is one of the largest numbers so far in this type of research,” he says. Leo BonProfessor of Virology and Head of the Department of Public Health Laboratory Sciences at the University of Hong Kong, who led the research.

“It was recorded whether the sample came from a patient who was vaccinated or not,” continues Bonn. This allowed us to determine the effect of vaccination on the evolution of the virus.

different vaccines

In Hong Kong, the government offered two vaccines during the Corona pandemic: the Pfizer vaccine, which was also widely used in the Netherlands, and the Chinese vaccine. Sinovac vaccine. These vaccines work in different ways. The Pfizer vaccine is a flexible vaccine that the body uses hobblesprotein, which is the protrusion by which the coronavirus gains access to cells. Sinovac is an “old-fashioned” vaccine that works with a whole, inactivated virus. “Previous studies have focused mainly on mRNA vaccines,” says Boone. “This makes Sinovac a unique part of our study.”

In addition, more than 90% of the collected virus genomes were read. He concludes, “A good study by a good research group.” Bert NestersProfessor of Medical Microbiology and Head of the Department of Virology at the University of Groningen, was not involved in this work.

Silent mutations

One of the questions Bunn and his colleagues focused on was: Does vaccinating people lead to new vaccine-resistant variants? “There are scientists who believe that vaccination can accelerate the evolution of the virus, and others who believe that this is not the case. Our results support the latter view, for both the Pfizer and Sinovac vaccines,” says Boone.

This does not mean that coronaviruses did not show mutations in vaccinated patients. But most of the mutations that were observed were called “silent” mutations: mutations that did not make the virus significantly more dangerous.

Because on average only one to three viral particles pass from person to person per human infection, Boone says, most of those silent mutations won’t jump over it. Non-silent mutations that are beneficial to the virus can spread in this way. This is why it is so important that we have demonstrated that grafting does not result in non-silent mutations in the host.

first across the line

By the way, Boone does not call his findings surprising. Nesters agrees. “Most selection will not be caused by vaccinations, but by how well a particular type of coronavirus reproduces. At this point, the omikron variant crossed the line first.