New Coronavirus Variant Could Become Dominant, Lead To More Covid-19, Deaths

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How bad will B.1.1.7 be?

Well, a new publication in the Centers for Disease Control and Prevention (CDC) Morbidity and Mortality Weekly Report (MMWR) indicates that this new variant of the Covid-19 coronavirus, first detected in the United Kingdom (U.K.), won’t be still and won’t be silent, to borrow a phrase from the movie She’s All That. In fact, it may soon be “all that,” the dominant circulating strain in the U.S. And that won’t be good or be best.

That’s because the B.1.1.7 variant of the Covid-19 coronavirus has a “fitness advantage” over the other strains of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) that have already been widely circulating in the U.S. No, fitness advantage does not mean that the little virus can do more push-ups or twerk longer. Rather the fitness of a microbe is its ability to survive and grow.

This new variant seems to be about 50% more transmissible than other existing strains. That’s quite a lot. Being 50% more likely to have the song “Who Let the Dogs Out” in your head and pass it along to others would make a big difference in your and everyone else’s well-being. Similarly, a virus that transmits 50% more easily could spread a lot faster and affect a whole lot more people sooner.

In fact, according to the CDC mathematical model described the MMWR publication, the B.1.1.7 strain should experience “rapid growth in early 2021, becoming the predominant variant in March.” So in about two months (or Scaramuccis), this B.1.1.7 strain could be the main one that’s circulating in the U.S. Even though B.1.1.7 mutant may not cause more severe disease or be more deadly than other existing strains, the CDC authors of the publication (Summer E. Galloway, PhD, Prabasaj Paul, PhD, Duncan R. MacCannell, PhD, Michael A. Johansson, PhD, John T. Brooks, MD, Adam MacNeil, PhD, Rachel B. Slayton, PhD, Suxiang Tong, PhD, Benjamin J. Silk, PhD, Gregory L. Armstrong, MD, Matthew Biggerstaff, ScD, and Vivien G. Dugan, PhD) had an ominous warning. A virus that can spread more readily and faster could result in more Covid-19 cases, which as the MMWR publication explained can increase, “the number of persons overall who need clinical care, exacerbating the burden on an already strained health care system, and resulting in more deaths.” In other words, the emergence of a virus that’s more contagious right in the middle of the worst part of the pandemic could be like turning up the volume on “Who Let the Dogs Out” while you are already overwhelmed.

Why is this new variant (or strain or lineage) more transmissible? Compared to your more run-of-the mill SARS-CoV2, the B.1.1.7 strain appears to have mutations resulting in 17 amino acid changes in the virus’ proteins, including eight amino acid changes in the spike protein. As they say in real estate and when getting massages, location, location, location. When it comes to the impact of mutations and amino acid changes in viruses, it’s all about location. And when it comes to the virus’s ability to infect your cells, it is not all about that bass. It’s all about the spike protein.

Do recall that the SARS-CoV2 looks like a tiny spiky massage ball. But in this case, the spikes aren’t for your pleasure. The virus uses these spikes to get into your cells sort of like how you use your hand to get into a refrigerator full of sushi, baba ghanoush, and avocados. The spikes connect to receptors on your cells with these cell receptors being analogous to a handle on a refrigerator door. The devious virus is actually too darn lazy to do all the work itself and may use enzymes from your cells to cut the spike protein so that it can connect with your cell receptors. Talk about helping me, help you, as Tom Cruise asked Renee Zellweger to do in the movie Jerry McGuire.

Amino acids are the building blocks for proteins like the spike protein. Removing or swapping any of these amino acids in the spike protein could potentially alter these spike proteins’ functioning and subsequently the virus’s ability to infect your cells. Changes in the spike protein could affect how well it can latch on to your cell’s receptors sort of like how wearing oven mitts, hooks, or underwear on your hands can affect your ability to grab on to the refrigerator handle.

The configuration of the spike proteins can affect the ability of your immune system to battle the virus as well. When the virus invades your body, your immune system can generate antibodies to defend against the virus. These antibodies have to recognize and latch on to the virus. So, changes in amino acids could affect the ability of your antibodies to do their thing.

This B.1.1.7 lineage has eight mutations resulting in the deletion of two amino acids and the swapping of six amino acids in the spike protein. But the key mutation may be N501Y one. N501Y may sound like the cousin of R2D2 but stands for a switch in the 501st amino acid in the spike protein from N (asparagine) to Y (tyrosine). This position is near the top of the spike protein, the part of the spike that connects with receptors on your cells. In fact, this change may make the fit between the spike protein and your cell receptors even tighter, thus allowing the virus to grab on better and do its infecting thing.

The N501Y may not be the only change that makes the B.1.1.7 strain more transmissible. Mutations that delete the 69th and 70th amino acids and either the 144th or 145th amino acid (which has typically been tyrosine) in the spike protein of the virus may make it harder for your antibodies to remain attached to the virus. This may make it tough for antibodies to hold on for just one day or one hour or one minute, in the words of Wilson Phillips, allowing the viruses to run more freely in your body.

Another mutation, the P681H mutation, in the spike protein may help you help the virus more. This mutation swaps a P (proline) amino acid to an H (histidine) amino acid on the stem of the Covid-19 coronavirus spikes. This change can then allow your cells’ enzymes reach the spikes to then cut the spikes and allow them to connect to your cell receptors. Yes, the Covid-19 coronavirus is akin to an awful and manipulative date, using you against yourself.

How will all of these changes affect your chances of getting re-infected with the SARS-CoV2 after you’ve already recovered from an infection? This is not quite clear yet. The fact that the mutations may affect the ability of your antibodies to “hold on” to the virus does raise the concern that natural immunity may not protect as well against this new variant.

Will the currently available Pfizer/BioNTech and Moderna Covid-19 vaccines work against the B.1.1.7 variant? These vaccines contain mRNA that serve as spike protein blueprints. When the mRNA is injected into your body, your immune system cells swallow them up. The ribosomes in your cells, which act as little factories for your cells, then use the mRNA as blueprints or recipes to then code for and produce spike protein. Your immune system then sees these spike proteins and in effect says, “what the bleep is going on here,” and then musters an immune response to the spike proteins. It also sets up a surveillance and defense system against this spike protein.

That’s why scientists and public health experts have been paying attention to the spikes on the surface of the Covid-19 coronavirus like some guys pay attention to their privates. The concern is that any changes to the spike proteins may affect how well the Pfizer/BioNTech and Moderna Covid-19 vaccines may protect against Covid-19. So far, there’s no indication that these vaccines won’t be effective against the B.1.1.7 variant. But stay tuned. Ferris Bueller said, “Life moves pretty fast. If you don’t stop and look around once in a while, you could miss it.” The same applies to mutations in the Covid-19 coronavirus.

Moreover, keep in mind that the effectiveness of the vaccine does depend on your risk of catching the virus. Increased risk may mean lower effectiveness. Borat’s man-kini swimsuit may be enough to protect you against the cold when you are in Turks and Caicos, both Turks and Caicos. However, move to a colder location like Wisconsin in the Winter and suddenly a small piece of fabric doesn’t offer you as much coverage as you need. Similarly, a variant of the virus that can spread more readily and widely may end up decreasing the overall effectiveness of the Covid-19 vaccine.

The emergence of the B.1.1.7 mutation is a reminder that we (humans, that is) are in a war against the Covid-19 coronavirus. The virus can adapt and change. So can humans. At this point, with the virus so widespread, a single intervention, such as the Covid-19 vaccines, will not be enough to contain this enemy. The more virus that circulates, the more likely it is for different variants to emerge. The key then is to do what countries like South Korea, Taiwan, New Zealand, and Australia have done: use multiple layers of interventions to keep the virus at bay, to controllable numbers.

For who claim that natural immunity or the Covid-19 vaccine means that you don’t have to social distance, don’t have to wear face masks, or don’t have to follow other public health recommendations, let’s be smart about things. The emergence of the B.1.1.7 variant has shown that you can’t be silent, be still, or be lazy about proper public health precautions. Instead, doing everything that you can to prevent the spread of the virus will be best.

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