How Much Longer?
By With so many people still contracting covid, filling up the hospitals, the fourth wave now, and vaccinations too, we must be getting to a point where there will be no more people to get sick, right?
I’ve had that intuition, but I know it’s mixed with my desire for the pandemic to be over, so I ran some numbers.
From my latest spreadsheet calculations on November 29, I get a figure of about 133 million Americans susceptible to the virus. This is going to be a very approximate calculation, so don’t worry about those three weeks.
There are other inaccuracies in that number, including that I assumed a that 20% of vaccinations have gone to people who have already had the virus. I recently saw a more reliable estimate of 25%. There are also imponderables, like how many have become susceptible because of waning immunity from infection or vaccine and how many, idiosyncratically, haven’t mounted an immune reaction to the vaccine. Then there’s the degree to which Omicron can escape previous immunity. All that makes the 133 million figure larger and the times longer.
Kyle Griffin reported this morning that there have been 1 million cases in the last 9 days. That rate will go up and down, but for our approximate purposes it’ll do.
If those 133 million people are to become immune by becoming infected, it will take
(133 x 9)/365 = 3 years, 102 days
for the pandemic to end. This is horrifyingly long. Our hospitals are not sized for the mass illness we are seeing with covid, which is why they fill up. But the percentage of population that is sick at any one time is not large. And many of those who contract covid, whether hospitalized or not, will experience “long covid.”
On the brighter side, people are being vaccinated at a rate of 55,000 per hour.
A preprint out today (Twitter thread) that shows that a third dose, particularly of the m-RNA vaccines, confers significant protection against Omicron, which is mystifying but nice. I usually don’t publicize single preprints, but this one supports other observations and expectations from the experts. I will use as a basis for 3 doses of vaccine being “fully vaccinated.”
If we are going to achieve population immunity by vaccination, we can do it more quickly than by infection. That calculation is
(133,000,000 x 3)/(55,000 x 24) = 300 days.
Another year. There are, of course, people who can’t be vaccinated for one reason or another, but they are a relatively small number. What may be more significant is that the susceptible people are not evenly distributed. Some of their enclaves may take longer to burn through than others.
The non-pharmaceutical interventions – masking, distance, ventilation – have always been intended to buy us time, to keep the numbers of cases to a level where hospitals can manage them. Continuing those interventions would also help to decrease cases, if we can miraculously take the vaccination route.
How much longer will the pandemic last? Somewhere between a year and 3 and a half years in the United States. It’s up to all of us.
Update (10:30 pm Eastern): I see in some comments a desire for a much more complex model. I’ll repeat that this is a rough guess. As far as I can see, the complexifications offered in the comments are unlikely to change the numbers in a big way. Simplification is a useful skill and means considering which complexities can be left out to obtain the kind of result that is wanted. I wanted a quick and admittedly dirty result: Can we expect things to get better in a month or a year? I made my assumptions explicit. If you want a different estimate, then make one and show how much better it is. But no, I’m not going to work out all those possibilities for you. And no, this estimate isn’t “wrong.” It is precisely what I stated above.
Cross-posted to Nuclear Diner