Initial Thoughts on the Delta Variant
I was hoping this blog was over.
In fact, I was halfway through my final COVID-19 blog where I thought I’d be signing off and moving on to new topics, but alas, before I could get that post out, the questions regarding COVID-19, and more specifically the Delta variant, have returned.
From March until July, I probably received one COVID-related question, but now with the Delta variant arriving to our country and the 24/7 headlines that have accompanied its arrival, the questions/comments from friends and family have returned which we’ll try to address below.
What is up with the Delta variant, I thought now that we have vaccines that COVID was over?
As we discussed in our January blog, the horse race between vaccinating as many people as possible versus mutant strains would be important to follow. All viruses mutate with the strongest, most potent strains surviving and eventually becoming the dominant strain. The hope was that we could vaccinate enough people where the number of hosts (i.e. – humans) that the virus had to replicate within would shrink to the point that no new, mutant strain would be able to replicate and spread to a global level.
Unfortunately in the case of the Delta variant, it won the metaphorical race and has seeded itself as the dominant COVID strain in the world. It will only continue to propagate until another more potent mutant strain comes along and overtakes it. It is estimated that only ~25% of the world population has received at least one shot of the vaccine meaning there are still lots of hosts for the virus to replicate and mutate.
While disappointing, this is not surprising and it’s likely that the Delta variant won’t be the last variant to strike.
That sounds concerning. How worried should I be?
It depends on whether you’re vaccinated or not. If you’re vaccinated, you’re still in very good shape. While the variant has led to increased breakthrough infections (positive COVID tests in fully vaccinated individuals) it’s not leading to severe infections and deaths in fully vaccinated individuals.
Data from Israel suggests that this strain is breaking through the vaccine more than prior strains with officials reporting 64% efficacy against Delta, but, hospitalizations and death rates amongst the vaccinated remain very low with 93% efficacy. Preliminary data from the U.K. shows similar percentages with their officials quoting a 79% efficacy against breakthrough infections and 96% efficacy against hospitalization and death.
Tracking U.S. data is incredibly difficult due to our lack of standardized/interoperable electronic health records (more on that in a future blog), but anecdotal data from states and statements from the CDC suggest that ~99% of deaths in the US are among unvaccinated individuals. We’re still quite early in understanding the extent of the Delta variant, but we’re not seeing hospitals filling up with vaccinated adults, rather we’re almost exclusively seeing hospitals fill up with unvaccinated individuals.
Do I need a booster shot?
Many people are asking about whether they need a booster shot, and the data remains gray. I haven’t seen compelling evidence one way or the other thus far. Pfizer recently announced they will seek approval for a booster in August followed almost immediately by the CDC and FDA issuing a joint statement saying no boosters are needed at this time.
So, who’s right?
It depends on how you interpret the data, your risk tolerance, and the implications of what it would mean from a logistics/operational perspective to recommend a booster shot at the national level.
I am personally encouraged by the current data that the vast majority of people with severe infections and/or dying are unvaccinated indicating that all the vaccines (including J&J) seem to be working quite well. My gut feeling is rather than rushing to approve a booster shot for the entire country, we should continue focusing on getting unvaccinated people vaccinated (more to come in a future blog), completing clinical trials for kids under 12 with the hope of safely approving the vaccine across all ages ASAP, and preparing for how we will roll out a booster efficiently and effectively when that time comes. Perhaps boosters will make sense in certain populations such as the elderly and immunocompromised, but it’s very difficult to make confident recommendations when working with incomplete and everchanging datasets.
While the Delta variant is certainly a setback, many of us control our own individual risk level by choosing whether to get vaccinated and what exposure risks we’re willing to tolerate on a daily basis.
And, to end on a positive note, it’s important to remember how much progress we’ve made in the past 12 months (when we had no vaccine) and 6 months (when we had a vaccine but no way to access it at scale). Clearly, COVID is not over and much work remains to be done, but all is not lost.
Stay safe and be well,
Harry