1/You have no doubt heard much lately about the recently designated #COVID19 #variant, #omicron.
I would like to distill what we know, what we do not know, and what this all means for you right now.
I would like to distill what we know, what we do not know, and what this all means for you right now.
2/On 11/26/21, the @WHO officially designated B.1.1.529 (#omicron) a "variant of concern."
It cited a "large number of mutations, some of which are concerning" and "preliminary evidence" of "an increased risk of reinfection with this variant.."
who.int/news/item/26-1…
It cited a "large number of mutations, some of which are concerning" and "preliminary evidence" of "an increased risk of reinfection with this variant.."
who.int/news/item/26-1…
3/In short, scientists are concerned because #omicron exhibits an unusual number of mutations across the #SARSCoV2 genome, with >30 on the spike protein.
The spike is the part of the virus that allows it to gain access to human cells and reproduce. (h/t @_nference)
The spike is the part of the virus that allows it to gain access to human cells and reproduce. (h/t @_nference)
4/Some of the mutations are well characterized with a known impact (transmission, immune evasion, etc.), but others were rarely observed until now and not well characterized, so their full significance is uncertain.
5/These mutations include ones we've seen before, like #E484K and #N501Y, which enhances #SARSCoV2 infection and transmission. nature.com/articles/s4158…
6/These mutations, combined with increasing case rates and positivity rates in Gauteng, South Africa, give rise to concern around this new variant.
It has not yet been detected in the US, but at this point, it is a matter of "when," not "if" it will be.
It has not yet been detected in the US, but at this point, it is a matter of "when," not "if" it will be.
7/There are a number of open questions that will take scientists time to understand.
For the umpteenth time in the #COVID19 pandemic, we are about to see the scientific process unfold before our eyes and in real time.
For the umpteenth time in the #COVID19 pandemic, we are about to see the scientific process unfold before our eyes and in real time.
8/One question is whether #omicron exhibits higher transmissibility than even the #delta variant.
Early, inferential evidence suggests that it may, but more complete epidemiological analysis is needed to quantify this and arrive at a more precise reproductive rate.
Early, inferential evidence suggests that it may, but more complete epidemiological analysis is needed to quantify this and arrive at a more precise reproductive rate.
9/Another question is whether #omicon leads to more severe illness.
Preliminary, anecdotal reports from providers in different countries suggest no difference in acuity, with unvaccinated patients at higher risk. This needs more study. news24.com/news24/southaf…
Preliminary, anecdotal reports from providers in different countries suggest no difference in acuity, with unvaccinated patients at higher risk. This needs more study. news24.com/news24/southaf…
10/A big question on everyone's mind is around immune system evasion--whether from vaccine-derived or virally derived immunity.
Immunologists emphasize that the immune response is multi-faceted, so even lower neutralizing titers may still mean a strong T-cell response.
Immunologists emphasize that the immune response is multi-faceted, so even lower neutralizing titers may still mean a strong T-cell response.
11/A related question is whether #omicron will be susceptible to treatments.
There is some concern around reduced effectiveness of monoclonal antibodies.
It's too early to know about forthcoming therapies, like the oral antiviral from Merck.
There is some concern around reduced effectiveness of monoclonal antibodies.
It's too early to know about forthcoming therapies, like the oral antiviral from Merck.
12/We also want to know whether currently available diagnostic tests will identify #omicron.
Thankfully, one of the more common tests, the BinaxNOW from @AbbottNews, will identify it.
abbott.com/corpnewsroom/d…
Thankfully, one of the more common tests, the BinaxNOW from @AbbottNews, will identify it.
abbott.com/corpnewsroom/d…
13/Likewise, the PCR testing that @MEPublicHealth performs will also identify #COVID19 if it happens to be caused by #Omicron.
14/The other big question is assessing the extent of spread already, and/or being on the lookout in the US and #Maine. That is done via genomic sequencing.
Thankfully, @MEPublicHealth has a strong partnership with @jacksonlab to perform #COVID19 sequencing in Maine.
Thankfully, @MEPublicHealth has a strong partnership with @jacksonlab to perform #COVID19 sequencing in Maine.
15/Some contextual observations:
-It's important to note that many variants generated a fair amount of concern initially, but later proved not to be drivers of spread/serious disease.
We should take the same approach here: gather data around key questions first, then react.
-It's important to note that many variants generated a fair amount of concern initially, but later proved not to be drivers of spread/serious disease.
We should take the same approach here: gather data around key questions first, then react.
16/For example, this graphic from @_nference notes other variants and their spike protein mutations. #omicron has a higher number, but we need data to know how that translates to transmission.
17/Also, even if if the individual-level severity from #omicron isn't different from delta, anything that causes more cases can lead to more hospitalizations even if the percentage affected remains the same.
18/The other thing to keep in mind is the evolutionary tradeoff between transmissibility and lethality.
A pathogen with a high case fatality rate kills off its host so quickly that it's unable to spread. We need data to know where #omicron lies on that spectrum.
A pathogen with a high case fatality rate kills off its host so quickly that it's unable to spread. We need data to know where #omicron lies on that spectrum.
19/What does this all mean for you?
First, know the facts. Trust reputable sources.
Second, the core tools (vaccination, masking, testing, ventilation, distancing) are likely the same ones we'll need for omicron.
First, know the facts. Trust reputable sources.
Second, the core tools (vaccination, masking, testing, ventilation, distancing) are likely the same ones we'll need for omicron.
20/If you haven't been vaccinated, do so. If you have, get a booster.
When you're in an indoor public setting, wear a mask.
Maintain ventilation/circulation indoors.
We don't yet know whether #omicron is a difference of degree or a difference of kind.
Stay tuned.
When you're in an indoor public setting, wear a mask.
Maintain ventilation/circulation indoors.
We don't yet know whether #omicron is a difference of degree or a difference of kind.
Stay tuned.
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