New Strains of Covid-19: What We Know About Coronavirus Variants


As expected, the first full winter of the Covid-19 pandemic in the United States has been brutal, leading to the total death toll. approaching the half million mark. There is also reason to be hopeful: the daily average of new Covid cases is now declining in 43 statesAnd while it’s off to a shaky start, the launch of Covid vaccines is well underway. But we are talking about SARS-CoV-2 and the virus does not care fit into any neat little narrative where spring comes and everyone gets vaccinated, which ultimately leads to the end of the pandemic and everyone to frolic without a mask in a field.

Along with the positive news, there have also been reports confirming cases of infections and deaths caused by new variants of the virus that causes Covid-19. While clearly not a step in the right direction, what does that mean exactly? Will be the existing vaccines be effective against these new strains? And should we do something different to protect ourselves? Here’s what you need to know, along with a breakdown of some of the more prevalent variants so far.

It is normal for viruses to change

It is common for viruses to mutate over time, in some cases forming new variants. “That’s why we get vaccinated against the flu every year, because the flu virus changes and we have a new variant every year,” he says. Dr. Karin Michels, professor and chair of the Department of Epidemiology, UCLA Fielding School of Public Health. “From now on, we may need to receive the annual Covid vaccine in addition to the annual flu vaccine.”

But not all variants have what it takes to stay: some form and then disappear, while others persist and spread. While there is an ever-changing list of new variants of SARS-CoV-2, three have emerged that worries scientists most, at least for now, besides the original virus.

The original virus

In December 31, 2019, health officials in Wuhan, China, reported on a cluster of cases of pneumonia of unknown cause, which they soon identified as a new coronavirus. Several weeks later, the International Committee on Taxonomy of Viruses (ICTV) announced that the new virus would be called “Coronavirus 2 severe acute respiratory syndrome” – or “SARS-CoV-2” for short – because while they are different, this virus is genetically related to the coronavirus responsible for the 2003 SARS outbreak.

On the same day, February 11, 2020, the World Health Organization (WHO) revealed that the disease caused by SARS-CoV-2 would be known as “Covid-19”. As of February 19, 2021, the WHO reports that there have been approximately 111 million cases of Covid-19, resulting in almost 2.5 million deaths.

The UK variant

Also known as variant B.1.1.7, this strain emerged from the UK in September 2020 and is now in more than 80 countries. The first confirmed case in the United States occurred in late December and until February 21, 2021, a total of 1,661 cases have been reported in 42 states.

Because it has been around for more than five months, scientists know more about this new strain than any of the others, but are still far from understanding its full impact. The latest research from England Public Health estimates that variant B.1.1.7 is 30 to 50% more transmissible – meaning it spreads more efficiently and quickly – than other strains. Other preliminary data from the UK suggest that the strain carries the possibility of more severe cases of Covid-19, and may be associated with a 30% higher risk of death compared to other variants, although as BBC News points out, “The evidence is not strong and the data is still uncertain.” the The CDC has predicted that B.1.1.7 will be the dominant strain in the United States next month.

The South African variant

Although variant B.1.351 originated in South Africa around the same time that the UK strain began to spread, the CDC says which was developed independently. It then became the dominant variant in Zambia in December 2020. Preliminary data estimates indicate that this strain is 50 percent more transmissible than previous strains circulating in South Africa. At this point, there there is no evidence that B.1.351 causes a more severe form of Covid-19, according to the CDC.

However, it is known that, like variants B.1.1.7 and P.1, variant B.1.351 contains a mutation in its peak protein that allows the virus to adhere to human cells more easily than the variant. original iteration of SARS-CoV-2. The first infections caused by the B.1.351 strain in the United States were identified in late January 2021, and to February 21, a total of 22 cases have been reported in 10 states.

The Brazilian variant

In early January 2021, a new strain of the virus known as P.1 was first identified in travelers from Brazil during routine Covid tests at an airport in Japan. By the end of the month, it had been detected in the United States, and to February 21, A total of five cases have been reported in four states.

There are there is currently no microbiological or epidemiological evidence of increased P.1 transmissibility, but the presence of a mutation also found in the UK and South African variants indicates that it is plausible, nor is there any evidence of an increase in severity of the resulting infections. Also, according to the CDC, this variant contains a set of additional mutations that can affect its ability to be recognized by antibodies, which means that if a person was infected with the parent virus, the antibodies they developed may not protect against this variant.

What does this mean for Covid-19 vaccines that have already been developed?

After all the drama and excitement of the race for a vaccine, discovering how these new variants make their way through the world, just like the launch of the vaccine it’s starting, it might feel a little heartbreaking. But that’s not the right way to look at it, he says Dr. Sten Vermund, an infectious disease epidemiologist and professor at the Yale School of Public Health.

Take, for example, data from recent clinical trials of Novavax, which indicated that its Covid vaccine candidate is about 85 percent effective against the UK variant and about 50 percent effective against the South African strain. But, as Vermund says, a “50 percent success rate is huge,” because that means there is a chance that there are enough cross-reactive antibodies to at least mitigate the severity of infection in all recipients. “So people who get infected and get sick are not going to get What sick, because having immunity to a mismatched variant is better than having no immunity at all, ”he explains.

So far both Pfizer-BioNTech Y Modern have reported that their vaccines are effective against variant B.1.1.7 (UK), but it didn’t go so well against Variant B.1.351 (first detected in South Africa). The efficacy of P.1 variant vaccines outside of Brazil is not yet known. Currently, both Pfizer Y Modern They are working on booster shots that, if needed, could offer greater protection to those who have received the original formulation of the vaccine.

For now, Vermund says we should continue to receive the currently available vaccines, as planned. “The faster we suppress transmission globally, the fewer variants will emerge and the more effective our current vaccines will be in real-world use,” he explains.

How can we protect ourselves from the new variants?

According to Vermund, we should take the same steps and precautions that have been recommended throughout the pandemic, except everyone really put in an effort this time. “People have not necessarily been rigorous in applying classic public health strategies,” he says. “For example, you see a lot of use of masks, which is not correct. Many people have the mask under their nose. A lot of people don’t have masks that fit well. “

Also, both Vermund and Michels emphasize the importance of keeping as much space as possible, but at least 6 feet, between you and other people. “A lot of people are very relaxed with their six foot distance,” explains Vermund. “And, you know, that wasn’t arbitrary. We came up with the six feet from real world data. People have to respect that. “

So how concerned should we be about the new variants? “Very concerned,” says Michels. “But even more concerned about new mutants that may bypass currently available vaccines, because the virus aims to evade our immune response. In fact, the newer variants are more aggressive and can make you sicker than the original strain, so I would be, and am, even more cautious. “



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