When Will the US Reach Covid Herd Immunity?

I want to turn attention to something else Fauci said during his interview with the New York Times:

“Ultimately, all pandemics burn themselves out,” he told us, adding: “So you have a choice. Do you want it to burn itself out and kill a lot more people and make a lot more people sick? Or do you want to do something about it to prevent further deaths and further illness?”

Of course, in typical bureaucrat fashion, he believes it’s a simple choice, and that if we want to “Do Something About” Covid, then we actually can. A government bureaucrat has never seen a problem he didn’t believe he had the ability to solve, so long as he is just given enough power and money.

I’ve been touting herd immunity (which is really what he means when he says “all pandemics burn themselves out”) as the only real solution to Covid, and once again I’m going to reiterate it.

More than a year ago, I concluded that the herd immunity threshold would be anywhere between 15-30% of the population possessing natural immunity (i.e., recovered from Covid).

That might seem like a ridiculous thing to say now, but even to this day, we’ve only had 48 million cases of Covid in the US, and against a total population of 331,000,000, that only comes out to about 14.5% of the country having gotten Covid.

The total number of recoveries is even lower–about 38 million, which comes out to 11.5% of the country having survived Covid and gotten the natural immunity that comes as a result.

However, it’s far more likely that the 15-30% herd immunity threshold was too low, and that the real number, at least for Covid, is higher.

I based my estimate of 15-30% on data from past influenza pandemics, found on Wikipedia, specifically this chart:

The obvious problem here is that there’s such a wide range in severity from pandemic to pandemic. The typical seasonal flu burns off, depending on the particular strain, at between 3-20%.

The three major flu pandemics between 1957-2009 (not including the 1977 Russian flu because there’s no data from the Soviet Union) had a herd immunity threshold of between 11-21%.

Going further back to the Spanish Flu and the 1889-90 flu pandemic, we can see a much wider range: 20-60% for the 1889 flu, and 33-56% for the Spanish Flu.

The odd thing is that the reproduction number of each individual flu pandemic doesn’t appear to explain why we see such great differences between them. Look at the Spanish Flu: it had an r0 of 1.80 and infected 33-56% of the world, while the 1968 Hong Kong flu, which also had an r0 of 1.80, infected just 14% of the world.

However, we might be able to explain this by pointing to advances in medicine between 1918 and 1968 that probably played a role in making the 1968 flu pandemic less severe. Plus, they were also two different strains of influenza, which is hugely important. And a final factor could be that the end of WWI and the mass movements of people around the globe also exacerbated the Spanish Flu pandemic’s severity.

At any rate, I only bring up this chart to show you where I got my 15-30% figure for Covid.

It was probably a dumb move on my part to take the global number of people infected in each pandemic and assume the US’s percentage of people infected was about the same. That’s obviously not the case. The global number is the average of hundreds of different countries that each individually vary wildly in terms of the number of people that actually get infected.

For instance, right now America has about 48 million confirmed cases of Covid, while the entire continent of Africa only has about 8.6 million reported. Now, whether that Africa figure is accurate or not is kind of beside the point: the point is that Africa has not experienced Covid at anywhere near the level severity places like America and Europe have. And that was probably the case in past pandemics as well.

The point here is that I was wrong to assume America’s herd immunity threshold would be the same as the global herd immunity threshold.

Anyway, while we’re not even officially at 15% of the US population recovered as of mid-November 2021, the real number of Americans infected with Covid is probably far higher than the official estimates, given that not everyone who has gotten Covid has gotten tested for it.

A Columbia University study from February of this year estimated that only 1 in 4 Covid cases in America were actually being reported and counted in official statistics. The study estimated that more than one-third of the US population had already been infected with Covid by February 2021:

“The numbers amplify greatly,” says Shaman. “When we look at confirmed cases, we’re really only seeing the tip of the iceberg.”

The rate of testing in the U.S. has improved over time. Shaman’s model finds that at the very start of the pandemic, only 1 in 10 cases were being reported. By early May, it had risen to 1 in 6. By September, it was up to 1 in 5.

Shaman estimates that, on average over the past three months, the official tally has been counting only 1 in 4 infections. In other words, says Shaman, to get a rough sense of the actual number of new cases per day, you should multiply the daily reported number by four.

The sustained periods of high transmission in the U.S. also mean that by now, quite a large share of the U.S. population has been infected beyond what the tallies of reported cases would indicate. Nationwide, Shaman estimates that about 120 million people have now been infected, just over a third of the U.S. population.

This is the chart Columbia University provided:

They estimated that back in February, 36% of the country had actually been infected despite official tallies only showing 8% had been infected.

Now obviously the total number of Covid cases in America has increased since February (specifically January 31, which is the cut-off date for the above chart).

According to Worldometers, on January 31, 2021, there were officially 26.7 million cases of Covid reported in the US since the start of the pandemic. As we know, we’re now at about 48 million.

If we multiply that number by 4, we get an estimated 192 million cases of Covid in the US to date, which is 58% of the country having had Covid.

If we multiply the “recovered” number by 4, we get about 152 million people in the US who have recovered from Covid, which comes out to a total immune percentage of 45.9%.

The real number could be higher than that, it could also be lower, but we’re going to go with 45.9%.

Now obviously this is way higher than my 15-30% estimate and the virus is still spreading, but as we can see with the older and more severe flu pandemics, they didn’t burn out until they hit potentially as high as 56-60%, so we could still have a ways to go on the herd immunity front.

But we still want to know where exactly the herd immunity threshold truly is, right? One way we might be able to find out is to look at the data for the individual states, which Columbia provides:

We can see that as of January 31, 2021, it was estimated that 52% of the state of North Dakota had been infected. Back then, the state’s total official case number was 97,000, and multiplied by 4, we get about 388,000 true cases.

The population of North Dakota right now is about 770,000, and the current official number of recovered persons in NoDak is 150,000. Multiplied by 4, we get 600,000 estimated recovered persons in the state, which comes out to about 78% of the state having natural immunity to Covid as of right now.

So, does North Dakota have herd immunity at this point?

Well, the virus is still spreading somewhat there:

They’re averaging about 477 new cases per day right now, but it appears to be tapering off somewhat, and the current wave is far less severe than the prior wave.

An encouraging sign is that North Dakota’s two major waves of Covid both happened at the same time of the year, which bolsters the case that waves of Covid are seasonal.

You can see that the main wave of Covid in North Dakota began in late July 2020 and peaked around mid-November.

The current, less severe wave they’re in also began around late July and topped out around mid-October.

In my view, it’s pretty clear that North Dakota is just about done with Covid. They’ve got nearly 80% of the state with natural immunity, which is why this current wave is nowhere near as bad as the one they went through last fall.

Based on the data out of North Dakota, I’d estimate the herd immunity threshold for Covid to be somewhere in the 85-90% range, unfortunately.

So why was my original 15-30% estimate so far off the mark? I think the main reason is that the Delta variant is way more infectious than the original Covid strain.

A study from just last month found the r0 of the Delta variant to be 5.08, compared to the “ancestral” strain of Covid-19’s r0 of 2.8.

In other words, the herd immunity threshold for Delta variant is a lot higher than past flu pandemics because the r0 of Delta variant is a lot higher than the r0 of past flu pandemic strains.

With some simple math, we can see where the herd immunity threshold is as long as we know the percent of the population that is already immune as well as the r0. I put it into a table:

Let me explain.

The first column is the percent of the population that’s immune, starting from 94% and going all the way down to 10%. From 10-80%, I just do it in increments of 10%, but once I got above 80%, I started doing it in increments of 1% all the way up to 94%.

The second column is simply the inverse of the immunity rate: it’s the spread odds. If 90% of the population is immune, the odds of an infected person spreading the virus to someone are 1 in 10.

The third column is the r0 multiplied by the spread odds. So, for example at a 50% immunity rate with an r0 of 5.08, we’d have a true r0 of 2.54.

The next column is where we start, patient zero, one infected person.

Column 5 shows us how many people patient zero would spread the virus to, given the virus’ r0 and the overall population’s immunity rate. This is simply column 3 multiplied by column 4.

Column 6 shows us how many people those infected by patient zero would spread the virus to, or column 5 multiplied by column 3. And then so on and so forth for the next columns.

As we can see, for a virus with an r0 of 5.08, it is not until we reach an overall immunity rate of 81% in the general population that the virus no longer spreads–in other words, we’ve reached herd immunity.

You can see that at any population immunity level below 81%, the virus still multiplies.

For example, at an immunity rate of just 10% and given an r0 of 5.08, one person will spread the virus to 4.572 people on average, who will then in turn spread the virus to 21 people, and those 21 people will then spread the virus to 95.6 people, who will spread it to 437 people, etc.

Even at an immunity rate of 70%, 1 person will spread the virus to 1.5 people on average, then 2.3, then 3.5, then 5.4 people, and then 8.2 people.

At an immunity rate of 80%, the virus still spreads at about a 1:1 ratio.

But when we hit 81% immunity, the virus is no longer multiplying. It is tapering off at each step along the way from Patient Zero.

So what does this mean for us? It means that in the US, we would need to have about 268 million people with natural immunity to achieve “herd immunity” from the virus. 268 million people is 81% of the country.

If we take the start date of Covid in the US to be March 10, 2020, it means 617 days have passed since the outbreak began. We also know that, if we accept Columbia university’s estimates that the true number of Covid cases is 4x higher than the officially reported total, we have had about 152 million people gain natural immunity over those 617 days, an average of about 246,000 per day.

This would mean that at the current pace, the US will not achieve herd immunity to Covid-19 until 1089 days have elapsed from the start of the pandemic.

Bottom line, this means that the US will not achieve natural herd immunity to Covid until…. March 3, 2023, or 15 months from now.

However, there are a ton of variables in play here. For one, the pace of achieving herd immunity could quicken (or slow).

And while the vaccine does not confer full immunity to recipients, perhaps it does confer some level of immunity. We haven’t even taking this into account here at all. Even if the vaccine grants immunity to just 25% of the people that get it, that’s still many millions of people that we can add into the “immune” category.

It’s also possible the Columbia researchers were wrong about the true number of Covid cases in the US–maybe the ratio of officially reported cases to unreported cases is higher than 4:1.

Let’s say it’s 5:1, meaning for every official reported Covid case, the true number is 5 times higher.

In that case we’d already have 190 million people naturally immune, an average of about 308,000 per day. That would mean we’re only currently 253 days away from hitting herd immunity, which would put our herd immunity threshold date at July 26, 2022.

Or, if the true ratio is 6:1, then that would mean we have nearly 230 million people already immune, which would put us very close to the 268 million herd immunity threshold number.

That would mean we’re only 108 days away from reaching herd immunity, and we’d reach it on March 3, 2022, rather than March 3, 2023.

And there’s actually good reason to believe that 4:1 ratio figure is indeed under-estimating the true number of people that have gotten Covid.

That 4:1 ratio was accurate as of February 2021, but not before that. As the article stated, in the early stages of Covid, the true case count dwarfed the official figures by about a 10:1 ratio.

As testing ramped up across the US, obviously that ratio started to come down, and by February of 2021 it was estimated to be 4:1.

But that still means it was higher than 4:1 for most of 2020.

This means it’s a certainty that the true number of people who have recovered from Covid in this country is higher than 152 million–perhaps significantly higher.

Another study published in July and conducted from March-May of this year concluded that the real number of Covid antibodies present in the general population (i.e., natural immunity) could be between 6-24x higher than the official figures state.

Now, the study was limited to 10 Covid testing sites and just 16,000 people, so that 24x number cannot possibly apply to the US. It would mean 912 million Americans have immunity to Covid, which is impossible.

But the study did still conclude the real number of Covid cases nationwide could be at least 6x higher than the official figures, which would put us on track for that March 2, 2022 herd immunity threshold date, and perhaps even earlier if we take into account vaccine immunity (which, again, we still know very little about).

I would take that March 3, 2023 as an extremely conservative and worst-case-scenario estimate. I think we’re much closer to achieving natural herd immunity than that.

If we’re really at 228 million true cases of Covid, that would mean we have an immunity rate in the general population of about 69%, and we are not that far off from the magic 81% number. At the current rate, we’re going up 1% in terms of population immunity every 9 days or so.

Now, the real question is, does any of this matter to the Vaccine Pushers and Mandaters and Covidiots? Probably not, because they don’t actually care about Covid, they care about jabbing people with Pfizer shots.

I guess I’d say the only thing I’m hoping for now is that the unnecessary and unconstitutional OSHA vaccine mandate gets stayed and delayed as long as possible until Covid truly does “burn out” sometime early next year, and hopefully at that point it will be a moot issue.

Something tells me it won’t be a moot issue, and that they would be trying to force vaccines on us no matter what.

Still, though, it would help quite a bit if Covid cases were virtually nonexistent while these tyrants were still trying to forcibly jab every last person in the country.

Bottom line, though, as I’ve been saying all along: natural herd immunity is the only way Covid will end, and I think we’re pretty close to reaching that threshold here in the US.

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