It’s a lot of news to process, and it comes without a lot of baseline knowledge about the virus itself.
It’s a lot of news to process, and it comes without a lot of baseline knowledge about the virus itself.
Staff writer at The Atlantic
As fall dips into winter in the Northern Hemisphere, the coronavirus has served up the holiday gift that no one, absolutely no one, asked for: a new variant of concern, dubbed Omicron by the World Health Organization on Friday.
Omicron, also known as B.1.1.529, was first detected in Botswana and South Africa earlier this month, and very little is known about it so far. But the variant is moving fast. South Africa, the country that initially flagged Omicron to WHO this week, has experienced a surge of new cases—some reportedly in people who were previously infected or vaccinated—and the virus has already spilled across international borders into places such as Hong Kong, Belgium, Israel, and the United Kingdom. Several nations are now selectively shutting down travel to impede further spread. For instance, on Monday, the United States will start restricting travel from Botswana, South Africa, Zimbabwe, Namibia, Lesotho, Eswatini, Mozambique, and Malawi.
It’s a lot of news to process, and it comes without a lot of baseline knowledge about the virus itself. Scientists around the world are still scrambling to gather intel on three essential metrics: how quickly the variant spreads; if it’s capable of causing more serious disease; and whether it might be able to circumvent the immune protection left behind by past SARS-CoV-2 infections or COVID-19 vaccines, or evade immune-focused treatments such as monoclonal antibodies. All are risks because of the sheer number of mutations Omicron appears to have picked up: More than 30 of them are in SARS-CoV-2’s spike protein, the multi-tool the virus uses to crack its way into human cells—and the snippet of the pathogen that’s the central focus of nearly all of the world’s COVID-19 vaccines. Alterations like these have been spotted in other troublesome variants, including Alpha and Delta, both of which used their super-speedster properties to blaze across the globe. (Omicron is only a distant cousin of both, not a direct descendant.) If—if—Omicron moves even faster than its predecessors, we could be in for another serious pandemic gut punch.
But it’s way too early to know if that’ll be the case. What’s known so far absolutely warrants attention—not panic. Viruses mutate; they always do. Not all variants of concern turn out to be, well, all that concerning; many end up being mere blips in the pandemic timeline. As Omicron knocks up against its viral competitors, it may struggle to gain a toehold; it could yet be quelled through a combination of vaccines and infection-prevention measures such as masks and distancing. Vaccine makers have already announced plans to test their shots’ effectiveness against the new variant—with data to emerge in the coming weeks—and explore new dosing strategies that might help tamp down its spread. Omicron might be set up for some success, but a lot of its future also depends on us.
To help put Omicron in perspective, I caught up with Boghuma Kabisen Titanji, an infectious-disease physician, virologist, and global-health expert at Emory University. Our conversation has been lightly edited for clarity and length.
Katherine J. Wu: Why don’t we yet know for sure how worried we need to be about Omicron?
Boghuma Kabisen Titanji: What we do know about the variant is this: Some of its spike-protein mutations have been seen in other variants and other lineages described earlier on in the pandemic, and have been associated with increased transmissibility and the ability of the virus to evade the immune response. What we don’t know, and what is really hard to predict, is what the combination of mutations will do together. This particular variant now appears to be outcompeting other circulating variants in South Africa—there have been these clusters of cases. That is actually what led to this variant being identified in the surveillance systems that they have in place there. That raises the concern that the variant is more transmissible or may be escaping the effects of the immune response induced by vaccines or infection from earlier strains. But we really don’t know that for sure yet.
The disconnect is this: The surveillance systems have worked exactly in the way they are designed to. It makes us know what to look out for. However, when these systems pick up a signal, we don’t immediately get the epidemiologic data we need to know all of the impacts a new variant can have. That takes time. Right now, we have a limited number of [viral genomic] sequences, and a limited number of cases. Now the alert is out. People will start looking for this new variant, not only in the countries that initially reported on this, but now worldwide. There’s now a search to make sure this variant is well-characterized. That’s when we will gain a better understanding of whether it’s causing more severe disease, how much it is escaping immunity, and how transmissible it is.
It’s important to keep in mind that other variants of concern have emerged before, including immune-evasive variants like Beta, which was first identified in South Africa, but eventually petered out.
Wu: Could we have seen the arrival of Omicron coming?
Titanji: Viruses are going to evolve regardless of what we do. There are things we can do to slow that down: barrier measures [such as masking], vaccinating. And there are things that we can do that can maybe speed up or aid the evolution of the virus. One is if we’re not doing what we need to do to prevent spread of the virus within the population. Every time a virus spreads, it gets another opportunity to infect a new host, and it gets another opportunity to evolve and change and adapt.
All of this means that it is worth having a conversation about whether the slow rollout of vaccines globally has had an impact. In certain parts of the world, not enough people have been given a measure of protection to allow them to be able to withstand infection, and to slow down transmission of the virus. Are we actually giving the virus an opportunity to spread unrestricted in certain places and drive its evolutionary trend? It’s basically exposing ourselves to the emergence of more variants. So this was predictable. If the virus has the opportunity to spread unchecked in the population, then we’re giving it multiple ways in which to evolve and adapt.
If we had ensured that everyone had equal access to vaccination and really pushed the agenda on getting global vaccination to a high level, then maybe we could have possibly delayed the emergence of new variants, such as the ones that we’re witnessing.
Wu: We’re still dealing with Delta, a previous variant of concern. Where do we go from here?
Titanji: A good place to start is reminding people that we are definitely not where we were two years ago, when SARS-CoV-2 emerged. We now have a better understanding of how the virus is transmitted from person to person. We have antivirals that are coming down the pike. We have a better understanding of how to manage and treat cases of people who do get infected. We have vaccines and incredible mRNA technology that allows us to adapt quickly to a changing virus, and we will have second-generation vaccines. It’s definitely not back to square one.
Secondly, this does not mean that the vaccines that people have are now completely useless—the doses they have received are not null and void. We have not yet seen a variant of concern emerge that has been able to completely escape the effect of vaccines. The immunity from the vaccines may be less protective, which may translate into more post-vaccine infections from a new variant, if it takes off. But that is yet to be determined.
We also know that a booster dose really does boost the antibody response. A new variant could dent the [protection offered by the immune system], but that usually happens in degrees. There is still going to be immune responsiveness from previous immunizations, and infections from ancestral versions of the virus. It may simply mean that you need more of those antibodies to be able to neutralize that new variant of concern. We also have T cells, which play a role and may not be as impacted by the variant.
This variant could not have chosen a worse time to emerge. We’re in flu season. This is a time when respiratory viruses tend to spread quite efficiently. And we are in the holiday season, and there’s a lot of traveling, and a lot of people getting together with family. But it’s certainly not the time for people to let their guard down, or relax on nonpharmaceutical interventions. People have to be mindful of wearing their mask when they’re out in public, or in crowded areas with people whose vaccination status they may not know. People have to be mindful of getting tested when they feel unwell, and isolating appropriately and doing all of those things that we have learned how to do over the course of the past two years, and that we know are effective in mitigating the spread of virus. The same measures will still work while we figure out just what this new variant means for us. Get your boosters. We’ll figure it out.
Wu: Several countries instituted travel bans this week, many of them primarily focused on African countries, where surveillance systems detected Omicron not long ago. How big of an impact might that make?
Titanji: Historically, there is a lot of evidence that by the time a travel ban is instituted, the virus has already gone … and potentially well beyond the borders of the countries that [the ban is] restricting travel from. Instituting travel bans as a knee-jerk reaction can send the wrong message to countries that are contributing to the global effort of virus surveillance. We could end up disincentivizing countries from reporting because they fear retaliation. There are other measures that could be taken to ensure that travel is safe. For example, to get an international flight, you have to be fully vaccinated as a requirement for most countries, or show proof of negative tests.
We will be better served if we put the emphasis on the countries that have seen the highest number of cases of this new emerging variant: providing them with the resources to actually contain the variant, and making sure that they have the resources for testing, for isolating cases, for doing the science that we need to better understand Omicron.
Wu: Some countries are already deep into their rollout of booster shots, and have, in recent months, lifted many restrictions; others are still barely making a dent in administering first doses. Regardless of where we go with Omicron, what does this say about our approach to COVID-19 as a global society?
Titanji: What this reiterates is that the world is so interconnected. We are in a global pandemic, and we cannot address this fully if we only have regional solutions. The solutions really have to be with a global mindset. And that global mindset means that the resources we have—vaccination, testing, access to therapeutics, and also the support to carry out appropriate surveillance—need to be equally accessible and equitably distributed in all parts of the world.
We can’t leave people behind. The virus will catch up with us regardless of where you are, regardless of what country you’re located in. You may be fully vaccinated, you may have had your booster, but you’re not that disconnected from the person who lives in a country where only 2 percent of the population is vaccinated, and who doesn’t have access to any of the treatments. We need to have less of an inward-looking focus. Because otherwise we’re just going to prolong how long we stay in this pandemic.
Tomado de https://www.theatlantic.com/science/archive/2021/11/omicron-coronavirus-variant-what-we-know/620827/
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