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As vaccine deployments accelerate – or in some cases stumble – in countries around the world, the SARS-CoV-2 strain has deployed new features, mostly in the form of rapid genetic mutations. There is some evidence that variants in recent months have made the virus more infectious or, in one case, possibly more deadly.
Variants of the virus are inevitable and often benign. The new coronavirus has probably mutated countless times without attracting the attention of epidemiologists. But new strains identified in the UK, South Africa, Brazil and California have given some infectious disease experts pause.
Several studies indicate that the strain known as the B117 variant, which is widespread in the UK, may be up to 70% more transmissible than the original virus. Two analyzes in California suggested that a new strain on the west coast, called B.1.426, accounted for a quarter of the infections examined. As the news slams between peaks of infection and inoculation efforts, it may appear that the world has entered a race between the variant and the vaccine.
“Mutation change is pretty quick,” said Dr Irwin Redlener, pediatrician and disaster preparedness advisor to New York City Mayor Bill de Blasio. “We don’t know where this is going. This is the reality, that we don’t know what to expect. What worries us most is that it could mutate to become vaccine resistant or partially resistant to vaccines. It would be awful. We could make changes to the vaccine, but that would slow everything down. “
Overall, the arrival of new threatening strains shouldn’t change the behavior of the average person, three epidemiologists and public health advisers told The Daily Beast. “In terms of vaccines and mitigation, it doesn’t change mitigation strategies because we know mitigation works,” said Dr. Arnold Monto, University of Michigan epidemiologist and professor of public health. “But that just means we have to be that much more serious about following these kinds of rules.”
“I think this primarily reinforces the urgency of every aspect of the pandemic response,” said Dr Joshua Sharfstein, associate dean of the Johns Hopkins Bloomberg School of Public Health. “Not just vaccination, but also contact tracing, precautionary taking and general vigilance… it will take a lot more than vaccinations because we don’t have enough vaccines overall in the short term.”
The British strain
Health officials in the UK first announced the detection of a new strain in mid-December, just a week after it became the first country in the world to start administering a vaccine. At a press conference, National Health Secretary Matt Hancock revealed that the new mutation has been seen in more than 1,000 patients, sparking a new wave of strict lockdowns across the country. The strain was thought to date back to mid-September. At the end of December, its spread correlated with a massive increase in the number of COVID-19 infections across the county.
The phrase “more contagious” can be misleading, Monto said. Data on the new strain doesn’t tell us, for example, that someone exposed to it will be infected faster than someone exposed to the old strain under identical conditions. It specifically refers to the speed at which viruses reproduce.
“Let’s look at this in terms of what we know,” Monto said. “What we do know is that this virus replicates better. In an individual, it takes less of this virus to cause infection. How do we know this? We don’t know about this in terms of “people in a room and how many are infected with one variant compared to the other”. But what is very clear is that this virus is more efficient and has gained the upper hand over the old virus. This tells us that he has some sort of advantage in reproducing.
British Prime Minister Boris Johnson announced at a press conference on Friday that the dominant variant could be up to 30% deadlier than the original. The findings came from an article published by the Advisory Group on New and Emerging Viral Threats – a study that Monto pointed out was based on a very small number of patients in only a handful of settings.
“A lot of other things could be linked to increased mortality,” he said, “including when you have, like the UK, more people in care. . It’s based on small numbers, so we can’t really say anything at this time. We cannot speculate.
“It was a statement he made,” Redlener said of Johnson sounding the alarm. “There really wasn’t much evidence to go on. But he drew a conclusion and made it public … For now, I will say Boris Johnson should have held his statement until there is more evidence.
The South African strain
Shortly after the British strain was first announced, a variant called B.1.351 appeared in South Africa. The new strain shared some mutations with its British predecessor, according to the CDC. It also appeared to have a higher transmission rate. Of most concern about the South African strain, however, was a new mutation in its genetic code that some experts believe could reduce the effectiveness of COVID-19 vaccines. Some preliminary studies – few of which were peer-reviewed – found that the E484K mutation in the South African variant limited the effectiveness of antibodies by up to 50 percent.
“It’s definitely a concern,” Redlener said, referring to a report on the studies of NBC’s Richard Engel. “It’s a concern because a legitimate scientist mentioned it. What we don’t know is the reliability of his studies that led him to this conclusion.
Monto found the findings less alarming, noting that the studies were drawn from a small body of research and very few real cases. “Ultimately, they’re trying to see in a lab if the blood from the vaccines neutralizes the variants as well as the original virus,” Dr Monto said. “Looks like they are and to date there are several articles. They say their test is good. Another says it’s not as good, but it’s okay.
Other strains
Another new variant has been detected in Japan among four travelers from Brazil, according to the CDC. Although relatively less is known about the Brazilian variant, Reuters reported on Friday that the new strain accounted for almost half of new infections in Manaus, the largest city in the Brazilian state of Amazonas.
Last summer, a strain of SARS-CoV-2 emerged in Denmark in association with the country’s mink farming industry, according to the WHO. The country has killed 17 million mink to prevent the virus from spreading to humans.
In California, scientists discovered a new variant at the end of December, shortly after the state suffered its biggest pandemic outbreak. According to Los Angeles Times, two research groups observed the new form while looking for evidence that the British strain had traveled west. Also highly transmissible, it now appears to be the fastest growing variant in the state. Despite the discovery, local officials and the media have largely blamed residents, who they say have stopped following lockdown guidelines.
“It’s a very complicated question – what causes an outbreak in a particular place,” Redlener said. “A lot has to do with basic compliance. But on top of that, there may be other strains that just haven’t been identified. We operate in the dark on a lot of things. It’s a lot of guesswork and speculation. We just have to keep looking.
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