The Worst-Case COVID-19 Predictions Turned Out To Be Wrong. So Did the Best-Case Predictions.

An argument for humility in the face of pandemic forecasting unknown unknowns


"Are we battling an unprecedented pandemic or panicking at a computer generated mirage?" I asked at the beginning of the COVID-19 pandemic on March 18, 2020. Back then the Imperial College London epidemiological model's baseline scenario projected that with no changes in individual behaviors and no public health interventions, more than 80 percent of Americans would eventually be infected with novel coronavirus and about 2.2 million would die of the disease. This implies that 0.8 percent of those infected would die of the disease. This is about 8-times worse than the mortality rate from seasonal flu outbreaks.

Spooked by these dire projections, President Donald Trump issued on March 16 his Coronavirus Guidelines for America that urged Americans to "listen to and follow the directions of STATE AND LOCAL AUTHORITIES." Among other things, Trump's guidelines pressed people to "work or engage in schooling FROM HOME whenever possible" and "AVOID SOCIAL GATHERINGS in groups of more than 10 people." The guidelines exhorted Americans to "AVOID DISCRETIONARY TRAVEL, shopping trips and social visits," and that "in states with evidence of community transmission, bars, restaurants, food courts, gyms, and other indoor and outdoor venues where people congregate should be closed."

Let's take a moment to recognize just how blindly through the early stages of the pandemic we—definitely including our public health officials—were all flying at the time. The guidelines advised people to frequently wash their hands, disinfect surfaces, and avoid touching their faces. Basically, these were the sort of precautions typically recommended for influenza outbreaks. On July 9, 2020, an open letter from 239 researchers begged the World Health Organization and other public health authorities to recognize that COVID-19 was chiefly spread by airborne transmission rather than via droplets deposited on surfaces. The U.S. Centers for Disease Control and Prevention (CDC) didn't update its guidance on COVID-19 airborne transmission until May 2021. And it turns out that touching surfaces is not a major mode of transmission for COVID-19.

The president's guidelines also advised, "IF YOU FEEL SICK, stay home. Do not go to work." This sensible advice, however, missed the fact that a huge proportion of COVID-19 viral transmission occurred from people without symptoms. That is, people who feel fine can still be infected and, unsuspectingly, pass along their virus to others. For example, one January 2021 study estimated that "59% of all transmission came from asymptomatic transmission, comprising 35% from presymptomatic individuals and 24% from individuals who never develop symptoms."

The Imperial College London's alarming projections did not go uncontested. A group of researchers led by Stanford University medical professor Jay Bhattacharya believed that COVID-19 infections were much more widespread than the reported cases indicated. If the Imperial College London's hypothesis were true, Bhattacharya and his fellow researchers argued, that would mean that the mortality rate and projected deaths from the coronavirus would be much lower, making the pandemic much less menacing.

The researchers' strategy was to blood test people in Santa Clara and Los Angeles Counties in California to see how many had already developed antibodies in response to coronavirus infections. Using those data, they then extrapolated what proportion of county residents had already been exposed to and recovered from the virus.

Bhattacharya and his colleagues preliminarily estimated that between 48,000 and 81,000 people had already been infected in Santa Clara County by early April, which would mean that COVID-19 infections were "50-85-fold more than the number of confirmed cases." Based on these data the researchers calculated that toward the end of April "a hundred deaths out of 48,000-81,000 infections corresponds to an infection fatality rate of 0.12-0.2%." As I optimistically reported at the time, that would imply that COVID-19's lethality was not much different than for seasonal influenza.

Bhattacharya and his colleagues conducted a similar antibody survey in Los Angeles County. That study similarly asserted that COVID-19 infections were much more widespread than reported cases. The study estimated 2.8 to 5.6 percent of the residents of Los Angeles County had been infected by early April. That translates to approximately 221,000 to 442,000 adults in the county who have had the infection. "That estimate is 28 to 55 times higher than the 7,994 confirmed cases of COVID-19 reported to the county by the time of the study in early April," noted the accompanying press release. "The number of COVID-related deaths in the county has now surpassed 600." These estimates would imply a relatively low infection fatality rate of between 0.14 and 0.27 percent. 

Unfortunately, from the vantage of 14 months, those hopeful results have not been borne out. Santa Clara County public health officials report that there have been 119,712 diagnosed cases of COVID-19 so far. If infections were really being underreported by 50-fold, that would suggest that roughly 6 million Santa Clara residents would by now have been infected by the coronavirus. The population of the county is just under 2 million. Alternatively, extrapolating a 50-fold undercount would imply that when 40,000 diagnosed cases were reported on July 11, 2020, all 2 million people living in Santa Clara County had been infected by that date.

Los Angeles County reports 1,247,742 diagnosed COVID-19 cases cumulatively. Again, if infections were really being underreported 28-fold, that would imply that roughly 35 million Angelenos out of a population of just over 10 million would have been infected with the virus by now. Again turning the 28-fold estimate on its head, that would imply that all 10 million Angelenos would have been infected when 360,000 cases had been diagnosed on November 21, 2020.

COVID-19 cases are, of course, being undercounted. Data scientist Youyang Gu has been consistently more accurate than many of the other researchers parsing COVID-19 pandemic trends. Gu estimates that over the course of the pandemic, U.S. COVID-19 infections have roughly been 4-fold greater than diagnosed cases. Applying that factor to the number of reported COVID-19 cases would yield an estimate of 480,000 and 5,000,000 total infections in Santa Clara and Los Angeles respectively. If those are ballpark accurate, that would mean that the COVID-19 infection fatality rate in Santa Clara is 0.46 percent and is 0.49 percent in Los Angeles. Again, applying a 4-fold multiplier to take account of undercounted infections, those are both just about where the U.S. infection fatality rate of 0.45 percent is now.

The upshot is that, so far, we have ended up about half-way between the best case and worst case scenarios sketched out at the beginning of the pandemic.

NEXT: Lawsuit: Immigrant Kids Are Suicidal, Eating Rotten Food in Secretive Detention Facilities

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  1. Thank God none of it was politicized. Can you imagine how unnecessarily bad the last year and half would have been?

    1. Ronny has to have this be a world ending apocalypse avoided or else it exposes just how incompetent he is at his job and just how far on the totalitarian side of the arguments he truly falls for no good reason.

      Sorry Ron, you’re no better than lysenkoists in the “science” you followed that has now been revealed to be more about political calculations than about public health. But at least Cuomo got a book deal out of it and fawning adulation from urinalists like you.

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    5. We aren’t good at the short-term predictions, but thank G that 97% of climate scientist agree that they can tell you what is going to happen in 3-4 decades from now.

      1. Everything predicted by the fools behind Captain Planet (The TV cartoon ) were wrong. 30 years ago.

  2. Assuming of course the deaths (with covid) are accurate, because we already know of cases where covid is listed as the primary cause of death in say a traffic accident or when they were already dying of cancer anyway. We’ll know after this year how many deaths were reduced in 2021 by covid killing off some people a few months early.

    I’d say cut that death count down by one third. So IFR is closer to 0.3% which is what I said before. A very bad flu season.

    1. Or saint Floyd of fentanyl.

    2. How do you know that it wasn’t a Covid coughing fit that caused the guy to veer off the road into a tree?

    3. You have any idea how dumb you sound repeating that talking point when the all cause mortality stats for the last year are available for everyone to see?

  3. Why isn’t Fauci in jail yet?
    He caused the Fauci flu.

    1. Was he in DC on the sixth?

    2. This is a great question. Instead he’s still on TV talking about the Delta variant and how it threatens our covid eradication plan.

      But even idiots like me understood the virus was too widespread to contain as soon as we had testing for it.

  4. Several things convinced me early on there was no need for any lockdowns or travel restrictions or masking.

    * The first warnings from the CCP were allegedly 3 weeks after the first outbreak. First, every government press release is hokum, and that goes doubly do for dictatorships. If it took three weeks to get their attention, it wasn’t serious.

    * That cruise ship, I think the Princess Diamond, which had 1500 (?) crew and passengers, all by themselves for a week, and yet only half (?) of everybody even caught the damn virus, and there were only a few deaths. Ebola-levels of danger this was not. I don’t care how much those crew and passengers tried to isolate themselves, they could’t have done that good a job.

    * Evolution means that if you isolate the weak cases at home, and move the serious cases to hospitals, you turn hospitals into breeding grounds for the deadlier viruses. The common cold is so weak precisely because it is so widespread. By quarantining the healthy and putting the sick together, you reward the more lethal variants and get more of them and more lethal versions of them. Quarantining healthy people was the dumbest move possible.

    1. Speaking of the ChiComs, I find it truly remarkable that more somehow hasn’t been made of the fact that they ludicrously claim that they’ve only had a grand total of 4,636 Coronavirus deaths. Best as I can tell, absolutely nobody of any real significance has ever called them out on this shit to this very day.

      Has the entire world really become that much of a bunch of complete and total frightened fucking pussies?

      1. Both left and right, and I do not understand that. The left sucks up to them with awe-struck eyes jealous of their command economy and society; why the right is so gullible and acquiescent I do not know. “Gullible” isn’t the right work for the right, but neither is “awe-struck”, but “acquiescent” sure is; while the left is pure awe-struck jealousy.

        1. Because both sides are jealous of the power of the Chinese government and how submissive the population is.

      2. Yes. Driving by themselves with a face diaper.

      3. Half the world has always been (and have) pussies. Our modern innovation is letting the pussies tell the non-pussies to shut up. And the non-pussies agreeing, thus adding to the pussy count.

        1. Not enough dicks to fuck the all the pussies and assholes. The dick count is low.

      4. Yes, a study of cremations and other data indicates about 10 times that number likely died in Wuhan alone by March 2020. Who knows how many died in China? It could be in the millions. Unlike a few countries that fared well, China was the epicenter and not geographically isolated. And they don’t have a young population or low population density. It is possible that draconian measures allowed them to do better than the worst hit countries. They probably don’t even know since they probably stopped counting cases and deaths early on.

        It should be noted that countries like India are severely undercounting too. Even in normal times, they don’t assign causes of death over 80% of the time.

    2. Bailey through out 2 different case studies on cruises and infection and hyped up invalidated models most of last year. He shouldn’t be a science writer.

    3. The USS Teddy Roosevelt had just one death. Only a third got sniffles or cough. A handful got sick. Just one died. Same time period.

  5. The upshot is that, so far, we have ended up about half-way between the best case and worst case scenarios sketched out at the beginning of the pandemic.

    On deaths or cases? Because we’re not anywhere near the halfway point between best case and worst case on deaths.

  6. The best case required no lockdowns. The worst case was justified to allow for government lockdowns. Fuck off Bailey.

  7. WHO no longer recommending vaccines for children under 18

    The COVID-19 vaccines are safe for most people 18 years and older, including those with pre-existing conditions of any kind, including auto-immune disorders. These conditions include: hypertension, diabetes, asthma, pulmonary, liver and kidney disease, as well as chronic infections that are stable and controlled.
    Children and adolescents tend to have milder disease compared to adults, so unless they are part of a group at higher risk of severe COVID-19, it is less urgent to vaccinate them than older people, those with chronic health conditions and health workers.
    More evidence is needed on the use of the different COVID-19 vaccines in children to be able to make general recommendations on vaccinating children against COVID-19.

    1. And facebook is censoring the recommendation.


      2. It’s only conservatives that are silenced by Silicon Valley, so nothing to see here. Move along.

    2. My heart breaks when I think about the kids who have already been subjected to the vaccines in experimental trials because their parents care more about virtue signaling that they aren’t icky Trump supporters than they care about being decent parents. And I’m sure there will be more and who knows what the side effects will be.

      1. Agree. Good parenting would solve a bunch problems we currently have.

  8. From the CDC, through March 2021:

    Total deaths (with all the caveats), 530,000
    Total infections, 115,000,000

    Fatality rate was thus .46%. If we discount the death total by a third, then the fatality rate was about .3%.

    And among those under 65, total deaths (121,000) compared to total infections (102,000,000) gives a fatality rate of .12%.

    1. Thank goodness we had doctors, medical research. and nurses to keep many of the worst cases alive.

      So here is a case report. This goes back to more than a year ago when it occurred.

      “A 56-year-old woman with diabetes referred to the emergency department, with complaints of cough, headache, high-grade fever, dyspnea, and hypoxemia on April 2020. Chest computed tomography (CT) showed bilateral ground-glass opacities. Laboratory results revealed normal complete blood count, high CRP titer, and LDH (904 IU/L), while PT, INR, and PTT were in the normal range. Nasopharyngeal sampling was positive for SARS-CoV-2 using real-time PCR method.”

      What is your next step?

      1. Thank goodness we had doctors, medical research. and nurses to keep many of the worst cases alive.

        Too bad they weren’t able to pursue certain treatments because narrative.

      2. Nebulizer, O2, Tylenol for fever, hydroxychloroquine, azithromycin.

      3. If you ask Dr. Peter McCullough: ivermectin. Thank God there are doctors like him who were willing to do something rather than sit around with a thumb up their ass.

  9. “COVID-19 cases are, of course, being undercounted.”

    No worries. To compensate, we grossly overcounted the deaths.

    1. Of course we know from 4 different locations that Bailey is full of shit and deaths were over counted. California county, d.c., Colorado state… all reduced fatalities by 30% when they audited records.

      1. The all-cause excess mortality statistic is the most reliable thing to evaluate the effect of covid

        1. Not necessarily. There were a lot of deaths due to lockdowns, with delayed care of survivable emergencies turning into deaths.

          Overdoses, cardiac failure, strokes, asthmatic respiratory distress… people were so scared to leave their homes, they died of lockdowns.

          Don’t forget routine treatments and prevention screenings and dialysis and chemotherapy that got delayed, leading to death.

          A lot more than just coronavirus infections will cause excess deaths.

          1. Some of those occurred but implausible to suggest they account for much of the excess deaths. Not sure why people still trying so hard to argue it’s “just the flu”. Especially weird when they jump on the lab leak theory. So we’re now going after China for leaking a harmless virus? Or are you saying there is a pandemic after all?

  10. “Back then the Imperial College London epidemiological model’s baseline scenario projected that with no changes in individual behaviors and no public health interventions, more than 80 percent of Americans would eventually be infected with novel coronavirus and about 2.2 million would die of the disease.”

    I got some news for you Ron; any model or projection based on people NOT changing their behavior when threatened is a waste of time.

    1. So we saved about 1.5 million lives?


    2. If the question you are trying to answer early on is ‘How dangerous is this disease’, then the model should be based on no change in human behavior. Only in virus behavior (where herd immunity does begin to mean something).

      If the question you are trying to answer is ‘What should we do about this’, then the model should include likely changes in human behavior because the default active policy (do nothing) still means some behaviors change without policy-level knowledge. Model the spread assuming an ‘unmanaged’ pandemic – eg 1918 flu – and the expected death count was 600k to 1 million in the first year (probably a bit more because the R0 (which also has elements of disease-based and human-based) for covid was higher than flu).

      This could have easily been managed as a basically Hayekian issue. What knowledge do we have about the disease? How does knowledge spread? What prophylactic NPI measures work and which ones don’t? How can we get THAT knowledge into the public realm? Doesn’t solve the problem but it gets us a long way there – with no coercion.

      We chose not to do any of that – HERE at Reason. Instead, the ICL model was simply painted as ‘worst-case scenario’. Which meant every bozo out there could just make shit up for an ‘optimistic’ scenario – and that fake shit would get the same media attention as everything else. And the politicized – here – had ‘making shit up’ as the GOAL.

      IOW – the absolute WORST people to try to figure out a Hayekian approach to this are the people here. Because a large contingent is not interested in knowledge. They are pathological liars and nihilists – about everything. Their public goal – for everything in the ‘public’ realm – is to spread disinformation and stir shit and create some bullshit post-modern paleo relativism. For that crowd the basic Hayekian presumption – What is the problem we wish to solve when we try to construct a rational economic order? – is false

  11. Dude, they’re not done being wrong. Not by a stretch.

  12. All I’ve got to say is that I’m pretty damn impressed by how fast millions of people became experts on virology and epidemiology. When you couple that with how fast they became climatologists and experts on the carbon cycle, they must have had a lot of time on their hands to study up on the science. Which they did, because most of them are barely-employed Gender Studies majors who have nothing but time on their hands.

    1. I am NOT a Gender Studies major.

      I am, however, an expert in gender studies.

      1. I’ve studied genders my entire life.

        1. One of two or did you double major?

    2. We might add that understanding the appeal to authority fallacy, Fauci’s duplicity, and the stupidity of giving bureaucrats so much power over our economy and our lives doesn’t require any specialized knowledge about virology or climatology.

      1. No, we need specially anointed experts to explain everything to us that we can see and assess for ourselves with two seconds of thought.

    3. They followed the science…..all the way to the Wuhan lab and concluded to go any further would be racist. So you see, science does have its limits.

    4. The issue is that the known science surrounding respiratory diseases was ignored. Now we are seeing that the known science prior to March 2020 was indeed correct about masks, lock downs, natural immunity, etc. The actual new information that turned out to be correct was effectiveness of ivermectin.

      Most all of Team Apocalypse’s predictions turned out to be wrong. Bailey is squarely in the Team Apocalypse camp.

  13. We didn’t know much of anything at right at the beginning. But that didn’t stop the superstitious rituals that coalesced around the ignorance.

    Case in point: We now know that the virus can’t survive on a hard surfaces. Yet my company is still making the janitors sanitize down the stairwell handrails twice a day, and requires sanitation of the coffee machine before AND after each use. By and coffee machine, I mean that automatic machine where the only thing you only touch is the glass selection panel. A half second touch on a glass screen necessitates sanitation before and after use. It’s fucking nuts.

    Doubly nuts because next week we get to open up completely for those who have been vaccinated. Yet we’ll still have to sanitize that fucking coffee machine.

    It’s a superstitious ritual, nothing more. And you can’t argue with superstitious people.

    p.s. I’m hoping one of these days the office manager who made all thse stupid rules will be behind me in line to use the microwave. In that case I WILL thoroughly sanitize it before and after use, thoroughly and methodically. Then double check that she does the exact same half hour ritual.

    1. “By and coffee machine, I mean that automatic machine where the only thing you only touch is the glass selection panel. A half second touch on a glass screen necessitates sanitation before and after use. It’s fucking nuts.”

      My workplace does the same thing. I touch a button on a machine to dispense water for 5 seconds, then I’m required to wipe the whole thing down with an alcohol towelette. It is indeed a ritual. Nature abhors a vacuum, and, for some, traditional religiosity has been replaced with new secular forms.

  14. 2 citizens arrested at school board meeting for unlawful assembly.

  15. The motion to proceed with the Senate version of H.R.1 just failed to advance in the Senate. Listening to the Democrats in the Senate talk about it, they’re either about to introduce a motion to do away with the filibuster or they’re getting ready to make other Democrats like Manchin out to be hateful racists for not doing away with it.

    If I were Mitch McConnell right now, I’d be on the phone with Manchin offering him anything I could–to get him to jump parties right now. Some of the big spending they have under consideration goes away with divided government. If Manchin jumps ship and caucuses with the Republicans, the Democrats will no longer be able to pass whatever spending bills they want through budget reconciliation.

    But they may need to demonize Manchin for supporting the filibuster for a while first–before he jumps ship. The progressives were already saying that the filibuster is a racist anachronism from the days of slavery. Now that it’s what’s standing between them and H.R. 1, the filibuster–and Democrats like Manchin who support it–are even more racist in the minds of progressives than they were before.

  16. “Humility”? If ‘humility’ means ‘abject submission to every-changing diktats’, sure.

  17. Come on Ron, you can’t compare the numbers from April of last year and April of this year and just multiply by what the study found the undercount was. Testing levels rose dramatically in later months which would have reduce the severity of the undercount. If the virus had shown up earlier than thought as many have posited, along with the seasonality of the virus, it’s likely there were a lot of people that had had it early on when testing levels were low.

  18. Covid-19 is the most dangerous disease that has killed lakhs of people. and check the latest PICME scheme.

  19. Was he in DC on the sixth?

  20. ….but, but, but both predictions were based on REAL SCIENCE!

  21. Also the vastly incorrect dire predictions were made by officially sanctioned organizations while the wildly optimistic stuff was fringe crap, so Bailey is not accounting for that huge bias. The overall error rate given the “credibility” of the source was biased toward incorrect dire predictions.

  22. What Ron outlines is literally the reason why COVID became so political. The disease itself was based in a world of nuance. And in our country, nuance is not something we understand. Therefore, each side was able to make of COVID what they wanted. It was the most awful thing ever to happen to man, or it was just a simple flu. Since the disease was neither of these things, it was remarkably possible to spin.

    If this had been the flu or Ebola, the political reaction would have been much, much less. But since COVID was in-between and surrounded with unknowns, it became a political football to everyone, as we can’t handle such nuance.

  23. COVID, if nothing else, has been perhaps the largest social psychology experiment ever. If you tend to hold apocalyptic views on things like climate change, smoking/vaping, and have low level of scientific literacy (ie most progs) you saw it as much worse than it actually is. If you are a bit more nuanced in your views, or don’t trust somebody just because the media has declared them an “expert”, then you did not.

    It would have been interesting to see if the sides would have flipped had Hillary been POTUS, and no, I don’t think she would have done much better at managing the response than orange man.

  24. Just say ‘Okay, I was wrong.”, Ron. You’ll feel better.

  25. The finding it was not spread by droplets should’ve told everyone right there that paper or cloth masks would be useless.

    1. They knew that in January 2020.

      Just as the mayor of Taipei knew it in the SARS scare many years ago. But he knew he couldn’t get sick people to stay home or cover up, because it would less to widespread shame. So he ordered everyone to mask up in public.

      This began the talismanic use of masks on healthy people in Asia.

      Make no mistake, no one educated in modern infection control ever considered masks effective in controlling respiratory germs.

  26. Yup just a bad flu season. Always was, always will be.

  27. Ronald, the only way to gauge the accuracy of the Stanford folks estimates is to compare their estimated infection numbers to the actual positive test cases at that time. Early April 2020. Testing was scarce then and their estimated total of actual infections can only be compared to the data they had at the time. You decided to compare their multiple to actual positive test a year later, when these tests were wide spread. To make a point, please use apples to apples comparisons. You would look smarter in doing so.

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