Well, there are some things to cover this week. First and foremost - last week brought us a large increase in cases in Easthampton. Cases are up significantly all over Western MA, including in Hampshire and Hampden counties. It's the general pattern in the state and the US right now.
We experienced a short surge in August and September as the delta variant became dominant. The relative brevity of the surge was a relief to data modelers and epidemiologists... and health care professionals... and all of us. Then cases plateaued and the forecasting models split. Would we maintain the plateau, eventually decreasing again, or would another surge begin? It would appear that the latter is unfortunately the case. But again - if anyone says they know for sure what will happen in a few weeks time, they're not understanding just how much they don't understand about this virus.
To top it off, in the past few days we have all learned about a new variant. The new variant was officially named "omicron" on November 26th by the World Health Organization. The WHO categorized omicron as a "variant of concern," which means that the mutations on the virus have the potential to be more contagious, more severe, or escape immunity or treatment, AND data indicates that at least one of those is true in human populations (meaning, it's not just theoretical). Scientists figure this out by sequencing the virus and identifying the mutations (compared to the original, alpha) and looking at real-world data.
I'll start with the bottom line about omicron and then put some specific details below for those who want more information. The bottom line is that omicron is probably more contagious than delta, which was more contagious than the original, alpha. We should be concerned, aware and vigilant, but we don't need to panic. The things that provide individual level and population level protection against all variants work for omicron as well. Keep doing what you're doing - get vaccinated and boosted, wear a high-quality well-fitting face mask (see the dashboard from October 21st for more information on masking), limit your time in crowded indoor locations and stay outside and in good ventilation as much as possible. Use rapid tests to stay on top of infection status at events you're planning to attend.
A quick aside about vaccine rates - the proportion of folks in Easthampton and Westhampton who are vaccinated continues to climb. I can't underscore enough how much this will benefit our community moving forward, particularly against severe outcomes. Relatedly, the lack of vaccine access and vaccination rates globally is concerning and epidemiologists agree that variants will continue to emerge until we have global vaccine coverage. To drive the importance of vaccination rates home again, the visual this week is a depiction of case rates by age group. It's not a surprise to see that the greatest burden of cases falls to the group not eligible or just recently eligible for the vaccine.
Now for those details on omicron. Here are some things that we know and don't know right now: 1) The omicron variant has 32 mutations on the spike protein. This is a lot. For comparison, the delta variant has 9 mutations on the spike protein. 2) We don't know what all 32 mutations mean in the real-world. We've seen some of these mutations before, and some are new to us. What that means is that we know some are "bad news" and we know some are "no big deal" and then there are some we have no idea about yet. 3) Early modeling is indicating that omicron is more contagious than delta, perhaps on the order of 5(ish) times more contagious. This is an estimate - we don't have this data to confirm yet. 4) Early data is indicating that omicron does not result in more severe disease, compared to other variants. Again, we don't know this for sure - we don't have the data to confirm yet. 5) Early data is indicating that omicron does not "evade" the immune response - that implies that prior immunity no longer works against the omicron variant. There may be some reduced effectiveness of the vaccines, but there's no reason to believe that vaccines won't be effective at all. Again, we don't know this for sure - we don't have the data to confirm yet. And finally, 6) we don't need to sequence for omicron to know if it's circulating. We haven't had a variant make itself so obvious on PCR tests until now - this is good news! We should be able to collect good real-time data on the spread of omicron. The CDC is reporting no evidence of this variant in the US as of November 26th.
There is lots of good information on omicron to be found in
this post and
this post from Your Local Epidemiologist.
Stay well,