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As expected, the first full winter of the Covid-19 pandemic in the United States was brutal, bringing the total death toll. approaching half a million. There are also reasons for hope: the daily average of new Covid cases is now down in 43 states, and, although on a fragile start, the deployment of Covid vaccines is underway. But it’s SARS-CoV-2 we’re talking about, and the virus doesn’t care fits into any tidy little story where spring comes and everyone gets vaccinated, ultimately leading to the end of the pandemic and everyone frolicking around a field without a mask.
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 this is clearly not a step in the right direction, what exactly does it mean? Will be the existing vaccines be effective against these new strains? And should we be doing something different to protect ourselves? Here’s what you need to know, plus a breakdown of some of the more popular variations to date.
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 the flu shot every year – because the flu virus changes and we have a new variant of it every year,” says Dr Karin Michels, professor and chair of the epidemiology department at UCLA Fielding School of Public Health. “We may need to get the annual Covid vaccine from now on in addition to the annual flu shot.”
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 emerged that worry scientists most – at least for now – in addition to the original virus.
The original virus
Sure December 31, 2019, health officials in Wuhan, China, reported a cluster of cases of pneumonia of unknown cause, which they quickly identified as a novel coronavirus. Several weeks later, the International Committee on Taxonomy of Viruses (ICTV) announced that the new virus would be called “Severe acute respiratory syndrome coronavirus 2” – or “SARS-CoV-2” for short – because although they are different, this virus is genetically linked to the coronavirus responsible for the 2003 SARS epidemic.
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 around 111 million cases of Covid-19, resulting in nearly 2.5 million deaths.
The UK variant
Also known as the B.1.1.7 variant, this strain was released 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 all the others, but are still far from understanding its full impact. The most recent search for Public health England considers that variant B.1.1.7 is between 30 to 50% more transmissible – which means it spreads more efficiently and faster – than other strains. Other preliminary data from the UK suggests the strain carries the possibility of more severe cases of Covid-19 and may be associated with a 30% increased risk of death compared to other variants – however, as BBC News points out, “The evidence is not strong and the data is still uncertain.” The CDC predicted that B.1.1.7 will be the dominant strain in the United States next month.
The South Africa variant
Although the B.1.351 variant originated in South Africa around the time the British strain began to spread, the CDC says that it developed independently. It then became the dominant variant in Zambia in December 2020. Estimates from preliminary data indicate that this strain is 50% more transmissible than the previous strains circulating in South Africa. At this point 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 the B.1.1.7 and P.1 variants, the B.1.351 variant contains a mutation in its spike protein that allows the virus to attach to human cells more easily than the original iteration. SARS-CoV-2. The first infections caused by the B.1.351 strain in the United States were identified at the end of 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 testing at a Japanese airport. 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 is currently no microbiological or epidemiological evidence of increased transmissibility of P.1 – but the presence of a mutation also found in the UK and South Africa variants indicates that it is plausible – and there is no evidence of an increase in severity infections that result. In addition, according to the CDC, this variant contains a set of additional mutations that can affect its ability to be recognized by antibodies – meaning that if a person has been infected with the original virus, the antibodies they have developed may not protect them. against this variant.
What does this mean for the Covid-19 vaccines that have already been developed?
After all the drama and excitement of the race for a vaccine, discover these new variants that are making their way around the world – just like vaccine deployment begins – may seem a little scary. But that’s the wrong way to look at it, says Dr. Sten Vermund, infectious disease epidemiologist and professor at the Yale School of Public Health.
Take, for example, recent clinical trial data Novavax, who reported that their Covid vaccine candidate is around 85% effective against the British variant and around 50% against the South African strain. But, as Vermund puts it, a “50 percent effectiveness rate is huge,” because that means there is the possibility that there is enough cross-reacting antibody to at least alleviate the severity of the disease. infection in all recipients. “So people who are infected and get sick will not be as sick, because it’s better to have immunity to an unpaired variant than not to have any immunity at all, ”he explains.
So far both Pfizer-BioNTech and Modern reported that their vaccines were effective against variant B.1.1.7 (UK), but not so good against the Variant B.1.351 (first detected in South Africa). The efficacy of the P.1 variant vaccines outside of Brazil is not yet known. Currently both Pfizer and Modern are working on booster shots which, if needed, could offer increased protection to those who received the original vaccine formulation.
For now, Vermund says we should continue to get the currently available vaccines, as planned. “The faster we eliminate transmission worldwide, the fewer variants there will be and the greater the effectiveness of our current vaccines in the real world,” he explains.
How to protect yourself from new variants?
According to Vermund, we should take the same measures and precautions that have been recommended throughout the pandemic – except that everyone is actually making an effort this time around. “People haven’t necessarily been rigorous in applying classic public health strategies,” he says. “For example, we see a lot of mask use that is not correct. A lot of people have their masks under their noses. Many people do not have properly fitted masks. “
Additionally, Vermund and Michels stress the importance of keeping as much space as possible – but at least six feet – between yourself and others. “A lot of people are very relaxed with their six-foot distance,” says Vermund. “And, you know, it wasn’t arbitrary. We found the six feet from real world data. People have to respect that.
So how worried should we be about new variants? “Very worried,” Michels says. “But even more concerned about new mutants that could bypass currently available vaccines – because the virus aims to elude our immune response. This is because the newer variants are more aggressive and can make you sicker than the original strain, so I would be – and am – even more careful.
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