Responses to “On testing.”

Responses to “On testing.”

My spouse posted my previous essay on social media, and I’d like to address some of people’s comments.  There were some excellent points! 

My apologies if I failed to address everything that people said, but I tried my best.

Scroll to find my responses to:

  1. A shutdown could have prevented the Covid-19 epidemic.
  2. We know that the current shutdown is either delaying or preventing deaths due to Covid-19. 
  3. Ending this epidemic with a vaccine would be ideal. 
  4. Ending the shutdown while requesting that at-risk people continue to self-isolate would save lives.
  5. Why is it urgent to end the shutdown soon?
  6. Why might more people die of Covid-19 just because we are slowing the spread of the virus?
  7. How is the shutdown causing harm?
  8. What about the rate at which people get sick?  Isn’t the shutdown worthwhile, despite the risks described above, if it keeps our hospitals from being overwhelmed?
  9. Don’t the antibody tests have a lot of false positives?
  10. What about the political ramifications of ending the shutdown?

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1: “A shutdown could have prevented the Covid-19 epidemic.”

If we’d acted early enough, we could have isolated all cases of Covid-19 and prevented this whole debacle.

But we didn’t.

Covid-19 is highly infectious, and we made no effort toward containment or quarantine until the virus was already widespread.  We took action in March, but we already had community transmission of Covid-19 by January.  Given where we are now, current models predict that the epidemic will continue until the level of immunity reaches somewhere near 70%.

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2: “We know that the current shutdown is either delaying or preventing deaths due to Covid-19.”

To date, the data suggests that the virus has only reached saturation inside a few closed environments, such as prisons.  In Italy, both the timecourse of mortality and the results of antibody studies suggest that infections were still rising at the time of their lockdown. 

Among the passengers of the Diamond Princess cruise ship, deaths peaked 21 days after infections peaked – if the virus had already reached saturation in Italy, we’d expect to see deaths peak sooner than 21 days after the lockdown began.  They did not.

So, again, this much is clear: worldwide, there was a significant new cause of death.  When we look at mortality data, we see the curves suddenly rise in many locations.  Some researchers, such as John Ioannidis, have speculated that Covid-19 causes death primarily in people with low life expectancy, in which case we would expect to see these mortality curves drop to lower-than-average levels after the epidemic ends.  But even then, it’s unprecedented to see a number of deaths that would usually occur over the course of a year all within a matter of weeks.

Covid-19 is killing people, and the shutdown is either delaying or preventing people’s death from Covid-19.

For the shutdown to actually prevent death, one of the following needs to happen:

1.) We create a vaccine, allowing our population to reach 70% immunity without as many people contracting the illness.

2.) We take action to change which segment of the population is exposed to the virus, allowing us to reach 70% immunity without as many at-risk people being exposed.

See #3 and #4, below.

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3: “Ending this epidemic with a vaccine would be ideal.”

Vaccination is great science.  Both my spouse and I love teaching about vaccines, in part because teaching the history of vaccine use is a good component of anti-racist science class.

Developing vaccines often takes a long time.  I’ve read predictions of a year or two; my father, an infectious disease doctor, epidemiologist, research physician who runs vaccine trials, and co-developer of Merck’s HPV vaccine, guesses that it will take about five years.

And then, for the vaccine to end this epidemic, enough people will need to choose to be vaccinated that we reach approximately 70% immunity.

The reason it’s worthwhile to compare Covid-19 to seasonal influenza is that a vaccine will only end the epidemic if enough people choose to get it.  Many people’s personal risk from Covid-19 is lower than their risk from seasonal influenza.  Will those people choose to be vaccinated?

Obviously, I would be thrilled if the answer were “yes.”  I’d love to live in a nation where people’s sense of altruism and civic duty compelled them to get vaccinated.  My family is up-to-date on all of ours.

But many privileged families in the United States have elected to be freeloaders, declining the (well tested, quite safe) measles vaccine with the expectation that other people’s immunity will keep them safe.  And, despite the well-documented dangers of influenza, only 40% of our population gets each year’s influenza vaccine.

Yes, the influenza vaccine tends to be less effective than many others – some years it gives as little as ten percent protection, other years about sixty percent protection.  By way of comparison, the HPV vaccine has over 90% efficacy.

A vaccine with low efficacy will still offer better protection when more people get it.  If a higher percentage of our population were vaccinated against influenza, then influenza transmission would drop, and so each person’s immunity, whether high or low, would be less likely to be challenged.

Also, the efficacy of influenza vaccines is measured in terms of the likelihood that vaccination prevents infection.  The influenza vaccine is not great at keeping people from getting sick.  But vaccination also tends to reduce the severity of your illness, even if you do catch influenza.  Because you got sick, it seems as though the vaccine “failed,” but your case might have been far more severe if you hadn’t been vaccinated.

The influenza vaccine saves lives.  In Italy, where fewer people choose to get vaccinated against influenza (about 15% compared to our 40% of the population), the death rate from influenza is higher.  Although it’s worth noting that this comparison is complicated by the fact that our health care system is so bad, with poor people especially having limited access to health care.  In the United States, people between the ages of 18 and 49 comprise a higher proportion of influenza deaths than anywhere in Europe.  Either our obesity epidemic or limited access to health care is probably to blame; possibly a combination of both.

In summary, for this plan to help us save lives, we will need to develop an effective vaccine, and then people will have to get it. 

I am quite confident that we can eventually develop a vaccine against Covid-19.  The virus includes a proofreading enzyme, so it should mutate more slowly than most RNA viruses.  We don’t know how long it will take, but we can do it.

I am unfortunately pessimistic that people will choose to get the vaccine.  And, unfortunately, when a low-risk person chooses to forgo vaccination, they’re not just putting themselves in harm’s way, they are endangering others.  Most vaccines elicit a weaker immune response in elderly or immunocompromised recipients – exactly the group most at risk from Covid-19 – which is why we spend so much time harping about herd immunity.

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4: “Ending the shutdown while requesting that at-risk people continue to self-isolate would save lives.

This plan has major downsides, too.  Because we didn’t take action soon enough, every plan we have now is bad.

Low-risk people can still die of Covid-19.  Even if they don’t die, Covid-19 can cause permanent health effects.  Covid-19 reduces your ability to get oxygen to your body and brain.  Even a “mild” case can leave your breathing labored for weeks – you’re not getting enough oxygen.  Your muscles will ache.  Your thoughts will be sluggish.

With a more severe case, people can be looking at heart damage.  Renal failure.  It would be cruel to look at all these long-term consequences and blithely call them “recovery.”

If our health care system were better, we’d treat people sooner.  The earlier you intervene, helping to boost people’s oxygen levels, the better outcome you’ll have.  There’s a great editorial from medical doctor Richard Levitan recommending that people monitor their health with a pulse oximeter during this epidemic.

If you notice your oxygen levels declining, get help right away.  Early intervention can prevent organ damage.  And you’ll be helping everyone else, too – the sooner you intervene, the less medical care you will need.

Because medical debt can derail lives, many people in this country delay treatment as long as possible, hoping that their problems will go away naturally.  That’s why people are often so sick when they show up at the ER.  I imagine that this is yet another reason – alongside air pollution, food deserts, sleep loss, and persistent stress exacerbated by racism – that poor communities have had such a high proportion of people with severe cases of Covid-19.

And I imagine – although we don’t yet have enough data to know – that financial insecurity caused by the shutdown is making this worse.  It’s a rotten situation: you have a segment of population that has to continue working during the shutdown, which means they now have the highest likelihood to be exposed to the virus, and they’re now under more financial strain, which might increase the chance that they’ll delay treatment.

We know that early treatment saves lives, and not everyone is sufficiently privileged to access that.

All this sounds awful.  And it is.  But, if we took action to shift exposure away from high risk groups, the likelihood that any individual suffers severe consequences is lower.

And there is another caveat with this plan – some people may be at high risk of complications for Covid-19 and not even realize it.  In the United States, a lot of people either have type 2 diabetes or are pre-diabetic and don’t yet realize.  These people have elevated risk.  Both smoking and air pollution elevate risk, but people don’t always know which airborn pollutants they’ve been exposed to.  (Which, again, is why it’s particularly awful that our administration is weakening air quality standards during this epidemic.)

Even if we recommended continued self-isolation for only those people who know themselves to have high risk from Covid-19, though, we would be saving lives.  The more we can protect people in this group from being exposed to the virus – not just now, but ever – the more lives we will save.

We won’t be able to do this perfectly.  It’ll be a logistical nightmare trying to do it at all.  People at high risk from Covid-19 needs goods and services just like everybody else.  We might have to give daily Covid-19 PCR tests to anyone visiting their homes, like doctors, dentists, and even delivery workers. 

At that point, the false negative rate from Covid-19 PCR tests becomes a much bigger problem – currently, these false negatives reduce the quality of our data (but who cares?) and delay treatment (which can be deadly).  A false negative that causes inadvertent exposure could cost lives.

Stores will need to set aside morning hours for at-risk shoppers, and undertake rigorous cleaning at night.  We know that infectious viral particles can persist for days on a variety of surfaces.

Some people will be unable to work, either because they or a close relative has high risk of Covid-19.  Some children will be unable to go to school.  We will need a plan to help these people.

We will have to work very hard to keep people safe even after the shutdown ends for some. 

But, again, if everyone does the same thing, then the demographics of people infected with Covid-19 will reflect our population demographics.  We can save lives by skewing the demographics of the subset of our population that is exposed to Covid-19 to include more low-risk individuals, which will require that we stratify our recommendations by risk (at least as well as we can assess it).

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5: “Why is it urgent to end the shutdown soon?

1.) By delaying Covid-19 deaths, we run to risk of causing more total people to die of Covid-19.

2.) The shutdown itself is causing harm.

See #6 and #7, below.

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6: “Why might more people die of Covid-19 just because we are slowing the spread of the virus?

[EDIT: I wrote a more careful explanation of the takeaways of the Harvard study. That’s here if you would like to take a look!]

This is due to the interplay between duration of immunity and duration of the epidemic.  At one point in time, seasonal influenza was a novel zoogenic disease.  Human behavior allowed the influenza virus to become a perpetual burden on our species.  No one wants for humans to still be dying of Covid-19 in ten or twenty years.  (Luckily, because the virus that causes Covid-19 seems to mutate more slowly than influenza, it should be easier to design a single vaccine that protects people.)

In the Harvard model, we can see that there are many scenarios in which a single, finite shutdown leads to more deaths from Covid-19 than if we’d done nothing. Note the scenarios for which the colored cumulative incidence curves (shown on the right) exceed the black line representing how many critical cases we’d have if we had done nothing.

Furthermore, their model does not account for people’s immunity potentially waning over time.  Currently, we do not know how long people’s immunity to Covid-19 will last.  We won’t know whether people’s immunity will last at least a year until a year from now.  There’s no way to test this preemptively.

We’ve seen that immunity to other coronaviruses fades within a year.  If immunity to Covid-19 is similar, we really don’t want to prolong the epidemic past a year.

If we could all go into stasis and simply not move for about a month, there’d be no new cases of Covid-19, and this virus would be gone forever.  But people still need to eat during the shutdown.  Many people are still working.  So the virus is still spreading, and we have simply slowed the rate of transmission.

This seems good, because we’re slowing the rate at which people enter the hospital, but it’s actually bad if we’re increasing the number of people who will eventually enter the hospital.

Based on our research with other coronaviruses, we expect that re-infection will cause a person to experience symptoms less severe than their first case of Covid-19.  But a re-infected person can still spread the disease to others.  And we don’t know what will happen if a person’s risk factors – such as age, smoking status, diabetes status, etc. – have increased in the time since their last infection.

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7: “How is the shutdown causing harm?

If you turn on Fox News, I imagine you’d hear people talking about the damage we’re doing to our economy.  They might discuss stock market numbers.

Who gives a shit?  In my opinion, you’d have to be pretty callous to think that maintaining the Nasdaq bubble is more important than saving lives.

At the same time, I think you’d have to be pretty callous to not feel extremely concerned by the United Nations’ policy brief, “The impact of Covid-19 on children.”

In this report, they estimate that the shutdown we’ve had so far will cause hundreds of thousands of children to die, many from malnutrition and the other health impacts of poverty.  The longer the shutdown continues, the more children will die.

That’s a worldwide number, and most of those children live outside the United States.  But I’d like to think that their lives matter, too.

The report also discusses the lifelong harm that will be inflicted on children from five months (or more!) of school closure.  Drop-outs, teen pregnancy, drug abuse, recruitment of child soldiers, and the myriad health consequences of low educational attainment.

I live in a wealthy college town, but even here there is a significant population of students who don’t have internet access.  Students with special needs aren’t getting the services they deserve.  Food insecurity is worse.

You’re lucky that privacy protections prevent me from sharing a story about what can happen to poor kids when all the dentists’ offices are closed.  I felt ashamed that this was the best my country had to offer.

As the shutdown continues, domestic violence is rising.  We can assume that child abuse is rising, also, but we won’t know until later, when we finally have a chance to save children from it.  In the past, levels of child abuse have been correlated with the amount of time that children spend in the presence of their abusers (usually close family), and reporting tends to happen during tense in-person conversations at school.

We know that online sex work has increased during the shutdown.  There is an increased supply of sex workers who are experiencing increasing financial insecurity.  We don’t yet have data on this, but I’d be shocked if the shutdown hasn’t led many to feel pressured into riskier acts for lower amounts of money, including meeting clients in isolated (and therefore unsafe) spaces.

The shutdown has probably made our drug epidemic worse (and this was already killing about 70,000 people per year in the U.S.).  When people are in recovery, one of the best strategies to stay sober is to spend a lot of time working, out of the house, and meeting with a supportive group in communal space.  Luckily, many of the people I know who are in recovery have been categorized as essential workers.

But any slip can kill someone recovering from addiction.  One of my friends froze to death last year.

A neighbor recently sent me a cartoon suggesting that the biggest harm caused by the shutdown is boredom.  (I’m going to include it, below, but don’t worry: I won’t spend too much time rattling sabers with a straw man.) And, for privileged families like mine, it is.  We’re safe, we’re healthy, we get to eat.  My kids are still learning – we live in a house full of computers and books.

But many of the 75 million children in the United States don’t live in homes like mine, with the privilege we have.  Many of our 50 million primary and secondary school students are not still learning academically during the shutdown.

Whether the shutdown is preventing or merely delaying the deaths of people at risk of serious complications from Covid-19, we have to remember that the benefit comes at a cost.  What we’ve done already will negatively impact children for the rest of their lives.  And the longer this goes on, the more we’re hurting them.

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8: “What about the rate at which people get sick?  Isn’t the shutdown worthwhile, despite the risks described above, if it keeps our hospitals from being overwhelmed?

In writing this, I struggled with how best to organize the various responses.  I hope it doesn’t seem too ingenuous to address this near the end, because slowing the rate of infection so that our hospitals don’t get overwhelmed is the BEST motivation for the shutdown.  More than the hope that a delay will yield a new vaccine, or new therapies to treat severe cases, or even new diagnostics to catch people before they develop severe symptoms, we don’t want to overwhelm our hospitals.

If our physicians have to triage care, more people will die.

And I care a lot about what this epidemic will be like for our physicians.  My father is a 67-year-old infectious disease doctor who just finished another week of clinical service treating Covid-19 patients at the low-income hospital in Indianapolis.  My brother-in-law is an ER surgeon in Minneapolis.  These cities have not yet had anything like the influx of severe cases in New York City – for demographic and environmental reasons, it’s possible they never will.  But they might. 

Based on the case fatality rate measured elsewhere, I’d estimate that only 10% of the population in Minneapolis has already been infected with Covid-19, so the epidemic may have a long way yet to go.

If we ended the shutdown today for everyone, with no recommendation that at-risk groups continue to isolate and no new measures to protect them, we would see a spike in severe cases.

If we ended the shutdown for low-risk groups, and did a better job of monitoring people’s health to catch Covid-19 at early, more-easily-treatable stages (through either PCR testing or oxygen levels), we can avoid overwhelming hospitals.

And the shutdown itself is contributing toward chaos at hospitals.  Despite being on the front lines of this epidemic, ER doctors in Minneapolis have received a 30% pay cut.  I imagine my brother-in-law is not the only physician who could no longer afford day care for his children after the pay cut.  (Because so many people are delaying care out of fear of Covid-19, hospitals are running out of money.)  Precisely when we should be doing everything in our power to make physicians’ lives easier, we’re making things more stressful.

We could end the shutdown without even needing to evoke the horrible trolley-problem-esque calculations of triage.  Arguments could be made that even if it led to triage it might be worthwhile to end the shutdown – the increase in mortality would be the percentage of triaged cases that could have survived if they’d been treated, and we as a nation might decide that this number was acceptable to prevent the harms described above – but with a careful plan, we need not come to that.

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9: “Don’t the antibody tests have a lot of false positives?

False positives are a big problem when a signal is small.  I happen to like a lot of John Ioannidis’s work – I think his paper “Why Most Published Research Findings Are False” is an important contribution to the literature – but I agree that the Santa Clara study isn’t particularly convincing. 

When I read the Santa Clara paper, I nodded and thought “That sounds about right,” but I knew my reaction was most likely confirmation bias at work.

Which is why, in the essay, I mostly discussed antibody studies that found high percentages of the population had been infected with Covid-19, like the study in Germany and the study in the Italian town of Robbio.  In these studies, the signal was sufficiently high that false positives aren’t as worrisome. 

In Santa Clara, when they reported a 2% infection rate, the real number might’ve been as low as zero.  When researchers in Germany reported a 15% infection rate, the real number might’ve been anywhere in the range of 13% to 17% – or perhaps double that, if the particular chips they used had a false negative rate similar to the chips manufactured by Premier Biotech in Minneapolis.

I’m aware that German response to Covid-19 has been far superior to our bungled effort in the United States, but an antibody tests is just a basic ELISA.  We’ve been doing these for years.

Luckily for us, we should soon have data from good antibody studies here in the United States.  And I think it’s perfectly reasonable to want to see the results of those.  I’m not a sociopath – I haven’t gone out and joined the gun-toting protesters.

But we’ll have this data in a matter of weeks, so that’s the time frame we should be talking about here.  Not months.  Not years.  And I’ll be shocked if these antibody studies don’t show widespread past infection and recovery from Covid-19.

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10: “What about the political ramifications of ending the shutdown?

I am, by nature, an extremely cautious person.  And I have a really dire fear.

I’m inclined to believe that ending the shutdown is the right thing to do.  I’ve tried to explain why.  I’ve tried to explain what I think would be the best way to do it.

But also, I’m a scientist.  You’re not allowed to be a scientist unless you’re willing to be proven wrong.

So, yes.  I might be wrong.  New data might indicate that writing this essay was a horrible mistake.

Still, please bear with me for a moment.  If ending the shutdown soon turns out to be the correct thing to do, and if only horrible right-wing fanatics have been saying that we should end the shutdown soon, won’t that help our current president get re-elected?

There is a very high probability that his re-election would cause even more deaths than Covid-19.

Failing to address climate change could kill billions.  Immigration controls against migrants fleeing war zones could kill millions.  Weakened EPA protections could kill hundreds of thousands.  Reduced access to health care could kill tens of thousands.

And, yes, there are horrible developments that neither major political party in the United States has talked about, like the risk that our antibiotics stop working, but I think it’s difficult to argue that one political party isn’t more dangerous than the other, here.

I feel pretty confident about all the scientific data I’ve discussed above.  Not as confident as I’d like, which would require more data, but pretty confident.

I feel extremely confident that we need to avoid a situation in which the far right takes ownership of an idea that turns out to have been correct.  And it’ll be dumb luck, just a bad coincidence.  The only “data” they’re looking at are stock market numbers, or many the revenue at Trump-owned hotels.

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EDIT: I also wrote a more careful explanation of the takeaways of the Harvard study. That’s here if you would like to take a look!

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Header image by Goran Paunovic.

On testing.

On testing.

UPDATE: Wow, this got a lot of readers! Honestly, though, I wrote a response to common questions and comments about this essay and it is probably a better read.

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My spouse recently sent me a link to the article “Concerns with that Stanford study of coronavirus prevalence” by Andrew Gelman, a statistician at Columbia University.  From reading this article, I got the impression that Gelman is a good mathematician.  And he raises some legitimate concerns. 

But I’ve noticed that many of the people criticizing the work coming out of the Ioannidis group – such as the study of how many people in Santa Clara county might have antibodies to Covid-19 – don’t seem to understand the biology underlying the numbers.

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First, some background: in case you haven’t noticed, most of the United States is operating under a half-assed lockdown.  In theory, there are stay-at-home orders, but many people, such as grocery store clerks, janitors, health care workers, construction workers, restaurant chefs, delivery drivers, etc., are still going to work as normal.  However, schools have been closed, and most people are trying to stand at least six feet away from strangers.

We’re doing this out of fear that Covid-19 is an extremely dangerous new viral disease.  Our initial data suggested that as many as 10% of people infected with Covid-19 would die.

That’s terrifying!  We would be looking at tens of millions of deaths in the United States alone!  A virus like this will spread until a majority of people have immunity to it – a ballpark estimate is that 70% of the population needs immunity before the epidemic stops.  And our early data suggested that one in ten would die.

My family was scared.  We washed our hands compulsively.  We changed into clean clothes as soon as we came into the house.  The kids didn’t leave our home for a week.  My spouse went to the grocery store and bought hundreds of dollars of canned beans and cleaning supplies.

And, to make matters worse, our president was on the news saying that Covid-19 was no big deal.  His nonchalance made me freak out more.  Our ass-hat-in-chief has been wrong about basically everything, in my opinion.  His environmental policies are basically designed to make more people die.  If he claimed we had nothing to worry about, then Covid-19 was probably more deadly than I expected.

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Five weeks have passed, and we now have much more data.  It seems that Covid-19 is much less dangerous than we initially feared.  For someone my age (37), Covid-19 is less dangerous than seasonal influenza.

Last year, seasonal influenza killed several thousand people between the ages of 18 and 49 in the United States – most likely 2,500 people, but perhaps as many as 5,800.  People in this age demographic account for about 10% of total flu deaths in the United States, year after year.

Seasonal influenza also killed several hundred children last year – perhaps over a thousand.

There’s a vaccine against influenza, but most people don’t bother. 

That’s shocking. 

Seasonal influenza is more dangerous than Covid-19 for people between the ages of 18 and 49, but only 35% of them chose to be vaccinated in the most recently reported year (2018).  And because the vaccination rate is so low, our society doesn’t have herd immunity.  By choosing not to get the influenza vaccine, these people are endangering themselves and others.

Some people hope that the Covid-19 epidemic will end once a vaccine is released.  I am extremely skeptical.  The biggest problem, to my mind, isn’t that years might pass before there’s a vaccine.  I just can’t imagine that a sufficient percentage of our population would choose to get a Covid-19 vaccine when most people’s personal risk is lower than their risk from influenza.

When I teach classes in jail, dudes often tell me about which vaccines they think are too dangerous for their kids to get.  I launch into a tirade about how safe most vaccines are, and how deadly the diseases they prevent. 

Seriously, get your kids vaccinated.  You don’t want to watch your child die of measles.

And, seriously, dear reader – get a flu vaccine each year.  Even if you’re too selfish to worry about the other people whom your mild case of influenza might kill, do it for yourself. 

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We already know how dangerous seasonal influenza is.  But what about Covid-19?

To answer that, we need data.  And one set of data is unmistakable – many people have died.  Hospitals around the world have experienced an influx of patients with a common set of symptoms.  They struggle to breathe; their bodies weaken from oxygen deprivation; their lungs accumulate liquid; they die.

Many people have been put on ventilators, but that’s often the beginning of the end.  Most people put on ventilators will die.  Among patients over 70 years old, three quarters who are put on ventilators will die

For each of these patients saved, three others are consigned to an agonizing death in the hospital, intubated among the flashing lights, the ceaseless blips and bleeps.  At home, they’d die in a day; in the hospital, their deaths will take three weeks.

And the sheer quantity of deaths sounds scary – especially for people who don’t realize how many tens of thousands die from influenza in the United States each year.

Or, consider: cigarette smoking causes 480,000 deaths per year in the United States, including 41,000 people who die from second-hand smoke exposure.  Those 41,000 aren’t even choosing to smoke!  But cigarettes kill them anyway.

Indeed, when people die of Covid-19, it’s often because their lungs fail.  Smoking is obviously a major risk factor for dying of Covid-19 – a significant portion of reported Covid-19 deaths could be considered cigarette deaths instead.  Or as air pollution deaths – and yet, our current president is using this crisis as an opportunity to weaken EPA air quality regulations.

Air pollution is a huge problem for a lot of Black communities in the United States.  Our racist housing policies have placed a lot of minority neighborhoods near heavily polluting factories.  Now Covid-19 is turning what is already a lifelong struggle for breath into a death sentence.

I would enthusiastically support a shutdown motivated by the battle for clean air.

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So, Covid-19.  We know how many people have died – already (CORRECTION AS OF APRIL 21) forty-two thousand in the United States

But if we want to know how scary this virus is, we need to know how many people were infected.  If that many people died after everyone in the country had it, then Covid-19 would be less dangerous than influenza.  If that many people died after only a hundred thousand had been infected, then this would be terrifying, and far more dangerous than influenza.

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Initially, our data came from PCR testing.

These are good tests.  Polymerase chain reaction is highly specific.  If you want to amplify a certain genetic sequence, you can design short DNA primers that will bind only to that sequence.  Put the whole mess in a thermocycler and you get a bunch of your target, as long as the gene is present in the test tube in the first place.  If the gene isn’t there, you’ll get nothing.

PCR works great.  Even our lovely but amnesiac lab tech never once screwed it up.

So, do the PCR test and you’ll know whether a certain gene is present in your test tube.  Target a viral gene and you’ll know whether the virus is present in your test tube.  Scoop out some nose glop from somebody to put into the test tube and you’ll know whether the virus is present in that nose glop.

The PCR test is a great test that measures whether someone is actively shedding virus.  It answers, is there virus present in the nose glop?

This is not the same question as, has this person ever been infected with Covid-19? 

It’s a similar question – most people infected with a coronavirus will have at least a brief period of viral shedding – but it’s a much more specific question.  When a healthy person is infected with a coronavirus, the period of viral shedding can be as short as a single day.

A person can get infected with a coronavirus, and if you do the PCR test either before or after that single day, the PCR test will give a negative result.  Nope, no viral RNA is in this nose glop!

And so we know that the PCR test will undercount the true number of infections.

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When we look at the age demographics for Covid-19 infections as measured by PCR test, the undercount becomes glaringly obvious.

Consider the PCR test data from the Diamond Princess cruise ship.  To date, this is our most complete set of PCR data – everyone on board was tested multiple times.  And from this data, it appears that very few children were exposed to the virus.

Friends, it is exceedingly unlikely that such a low percentage of children were exposed to this virus.  Children are disgusting.  I believe this is common knowledge.  Parents of small children are pretty much always sick because children are so disgusting. 

Seriously, my family has been doing the whole “social distancing” thing for over a month, and yet my nose is dripping while I type this.

Children are always touching everything, and then they rub their eyeballs or chew on their fingers.  If you take them someplace, they grubble around on the floor.  They pick up discarded tissues and ask, “What’s this?”

“That’s somebody’s gross kleenex, is what it is!  Just, just drop it.  I know it’s trash, I know we’re not supposed to leave trash on the ground, but just, just drop it, okay?  Somebody will come throw it away later.”

The next day: “Dad, you said somebody would throw that kleenex away, but it’s still there!”

Bloody hell.  Children are little monsters.

It seems fairly obvious that at least as high a percentage of children would be infected as any other age demographic.

But they’re not showing up from the PCR data.  On the Diamond Princess cruise ship, the lockdown began on February 5th, but PCR testing didn’t begin until February 11th.  Anyone who was infected but quickly recovered will be invisible to that PCR test.  And even people who are actively shedding viral particles can feel totally well.  People can get infected and recover without noticing a thing.

We see the same thing when we look at the PCR data from Italy.  If we mistakenly assumed that the PCR data was measuring the number of infections, and not measuring the number of people who were given a PCR test while shedding viral particles, we’d conclude that elderly people went out and socialized widely, getting each other sick, and only occasionally infected their great-grandchildren at home.

Here in the United States, children are disgusting little monsters.  I bet kids are disgusting in Italy, too.  They’re disgusting all over the world.

A much more likely scenario is that children spread this virus at school.  Many probably felt totally fine; some might’ve had a bad fever or the sniffles for a few days.  But then they recovered.

When they got their great-grandparents sick – which can happen easily since so many Italian families live in multigenerational homes – elderly people began to die.

So we know that the PCR test is undercounting the true number of infections.  Unless you’re testing every person, every day, regardless of whether or not they have symptoms, you’re going to undercount the number of infections.

In a moment, we can work through a way to get a more accurate count.  But perhaps it’s worth mentioning that, for someone my age, Covid-19 would seem to be about as dangerous as influenza even if we assumed that the PCR data matched the true number of infections.

If you’re a healthy middle-aged or young person, you should not feel personally afraid. 

That alone would not be an excuse to go out and start dancing in the street, though.  Your actions might cause other people to die. 

(NOTE & CORRECTION: After this post went up, my father recommended that I add something more about personal risk. No one has collected enough data on this yet, but he suspects that the next most important risk factor, after smoking and age, will be type 2 diabetes. And he reminded me that many people in their 30s & 40s in this country are diabetic or prediabetic and don’t even realize it yet. Everyone in this category probably has elevated risk of complications from Covid-19.)

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After you’ve been infected with a virus, your body will start making antibodies.  These protect you from being infected again.

Have you read Shel Silverstein’s Missing Piece book?  Antibodies work kind of like that.  They have a particular shape, and so they’ll glom onto a virus only if that virus has outcroppings that match the antibody’s shape.  Then your body sees the antibodies hanging out on a virus like a GPS tracker and proceeds to destroy the virus.

So to make an antibody test, you take some stuff that looks like the outcroppings on the virus and you put it on a chip.  Wash somebody’s blood over it, and if that blood contains antibodies that have the right shape to glom onto the virus, they’ll stick to the chip.  All your other antibodies, the ones that recognize different viruses, will float away.

An antibody test is going to be worse than a PCR test.  It’s easier to get a false positive result – antibodies are made of proteins, and they can unfold if you treat them roughly, and then they’ll stick to anything.  Then you’ll think that somebody has the right antibodies, but they don’t.  That’s bad.

You have to be much more careful when you’re doing an antibody test. I wouldn’t have asked our lab tech to do them for me.

An antibody test is also going to have false negatives.  A viral particle is a big honking thing, and there are lots of places on its surface where an antibody might bind.  If your antibodies recognize some aspect of the virus that’s different from what the test manufacturers included on their chip, your antibodies will float away.  Even though they’d protect you from the actual virus if you happened to be exposed to it.

If you’re a cautious person, though – and I consider myself to be pretty cautious – you’d much rather have an antibody test with a bunch of false negatives than false positives.  If you’re actually immune to Covid-19 but keep being cautious, well, so what?  You’re safe either way.  But if you think you’re immune when you’re not, then you might get sick.  That’s bad.

Because antibody tests are designed to give more false negatives than false positives, you should know that it’d be really foolish to use them to track an infection.  Like, if you’re testing people to see who is safe to work as a delivery person today, use the PCR test!  The antibody test has a bunch of false negatives, and there’s a time lag between the onset of infection and when your body will start making antibodies.

It can be dangerous to use antibody tests to address the wrong questions.

If you use the antibody test on a bunch of people, though, you can tell how many were infected.  And that’s useful information, too.

In the town of Robbio in Italy (pop. 6,000), the PCR test showed that only 23 people had been infected with Covid-19.  But then the mayor implored everyone to get an antibody test, and 10% of people had actually been infected with – and had recovered from – Covid-19.  Most of them couldn’t even recall having been sick.

The PCR test measured 23 cases.  The antibody test suggested there’d been at least 600.  And antibody tests, by design, will generally have a bunch of false negatives.  When a team at Stanford assessed the antibody tests manufactured by Premier Biotech in Minneapolis, they found that for every 3 people who’d been infected with Covid-19, the tests registered only 2 positives.

I don’t know who made the tests used in Robbio – maybe they were a little better, maybe they were a little worse.  Based on my experience, I wouldn’t be so surprised if the true infection rate with Covid-19 in that town was really just 10% – nor would I be surprised to hear that the chips had a high false-negative rate and that the infection rate was 20% or more.

If you calculate the fatality rate of Covid-19 in Italy by assuming that the PCR tests caught every infection, you’d get a terrifying 10%.

If you instead assume that many other towns had a similar infection rate to Robbio, you’ll instead calculate that the fatality rate was well under one percent. 

Italy has higher risk than the United States due to age demographics, smoking rates, and multigenerational households – and even in Italy, the fatality rate was probably well under one percent.

When researchers in Germany randomly chose people to take a Covid-19 PCR test (many of whom had no symptoms), they found that 2% of the population was actively shedding virus – a much higher number of cases than they would have found if they tested only sick people.  And when they randomly chose people to take an antibody test, they found that 15% had already recovered from the infection (again, many of whom had never felt sick).  According to these numbers – which are expected to be an undercount, due to false negatives and the time lag before antibody production – they calculated a case fatality rate of 0.37%

That would be about three-fold more dangerous than seasonal influenza.

In the United States, our bungling president gutted the CDC, leaving us without the expertise needed to address Covid-19 (or myriad other problems that might arise).  During the first few months of this epidemic, very few people managed to get a PCR test.  That’s why our data from the PCR tests is likely to be a dramatic undercount – indeed, when we finally started producing accurate tests, the apparent growth in Covid-19 caseload superimposed with the growth in test availability.

In the absence of good PCR data, we have to rely on antibody data to track infections after the fact.  Which is why a town in Colorado with zero reported infections, as measured by PCR, had sufficiently widespread exposure that 2% of the population had already recovered from Covid-19.

And it’s why the data from the Stanford Santa Clara county study is so unsurprising. 

Yes, there were problems with the Stanford study’s data collection – they displayed advertisements to a random selection of people, but then a self-selected subset responded.  The pool of respondents were enriched for white women, but Santa Clara’s outbreak probably began among Asian-Americans.  And we all know that random sampling doesn’t always give you an accurate depiction of the population at large – after all, random polling predicted that a competent president would be elected in 2016.

Now look at us.

It’s also likely that people with a poor understanding of the biology could misinterpret the result of the Stanford study.  They found that PCR tests had undercounted the infection rate in Santa Clara county, at the time of this study, by 85-fold.

It would be absurd to assume that you could simply multiply all PCR results by 85 to determine the true infection rate, but some people did.  And then pointed out the absurdity of their own bad math.

In places where more people are being tested by PCR, and they’re being tested more often, the PCR results will be closer to the true infection rate.  If you gave everyone in the United States a PCR test, and did it every day, then the PCR data would be exactly equal to the true infection rate.

If we had data like that from the beginning, we wouldn’t have been scared.  We would’ve known the true case fatality rate early on, and, also, at-risk people could’ve been treated as soon as they got infected.  We’d be able to save many more lives.

If access to health care were considered a basic right in the United States, we might’ve done something like this. 

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In Italy, it seems like Covid-19 is three- or four-fold more dangerous than seasonal influenza.  My guess is that Italy might have had about 50,000 deaths if they hadn’t enacted the lockdown.

In the United States, on a population level, Covid-19 is probably also more dangerous than seasonal influenza.  But there’s a big difference in terms of the distribution of risk.

The New York Times is running a series with short biographies of people who’ve died of Covid-19.  As of noon on April 17, about 10% of the people profiled were younger than 35.

10% is roughly the proportion of young people who die of seasonal influenza.  But only 1% of Covid-19 deaths are people younger than 35.  The news reports don’t always make clear how much the risk of Covid-19 is clustered in a small segment of the population.

This has serious implications for what we should do next.  If we were dealing with a virus that was about three-fold more dangerous than seasonal influenza for everyone, we might just return to life as normal.  (Indeed, we carried on as normal during the bad years when seasonal influenza killed 90,000 people instead of last year’s 30,000.)

Because the risk from Covid-19 is so concentrated, though, we can come up with a plan that will save a lot of lives. 

Healthy people under retirement age should resume most parts of their lives as normal.  Schools should re-open: for students, Covid-19 is much less dangerous than seasonal influenza.  I think that people should still try to work from home when possible, because it’s the right thing to do to fight climate change.

At-risk people should continue to isolate themselves as much as possible.

This sounds crummy, but at-risk people would just continue to do the thing that everyone is doing currently.  And the plan would save many lives because the epidemic would end in about 3 months, after the virus had spread to saturation among our nation’s low-risk cohort. 

Indeed, when a team of researchers from Harvard’s School of Public Health modeled the Covid-19 epidemic, they found that social distancing was generally unhelpful.  That’s what their data show, at least – but in their abstract, they instead recommend that we continue social distancing for the better part of two years.

Their data are easy enough to understand.  In each of these graphs, they show a blue box for how long social distancing would last, and then four colored lines to represent how many infections we’d see if we did no social distancing (black), medium quality social distancing (red), good social distancing (blue), or excellent social distancing (green).

So, from top to bottom, you’re looking at the graphs of what happens if we do a month of social distancing … or two months … or three, or four … or forever.

And you can see the outcomes in the panels on the right-hand side.  The black line shows what would happen if we did nothing.  Infections rise fast, then level off after the virus has reached saturation.  There are two important features of this graph – the final height that it reaches, which is the total number of severe cases (and so a good proxy for the number of deaths), and the slope of the line, which is how fast the severe cases appear.  A steeper hill means many people getting sick at the same time, which means hospitals might be overwhelmed.

So, okay.  Looking at their graphs, we see that social distancing saves lives … if we do it forever.  If you never leave your house again, you won’t die of Covid-19.

But if social distancing ends, it doesn’t help.  The slopes are nearly as steep as if we’d done nothing, and the final height – the total number of people who die – is higher.

(Often, one of their curves will have a gentler slope than the others — usually the good-but-not-excellent social distancing seems best. So you’d have to pray that you were doing a precisely mediocre job of not infecting strangers. Do it a little better or a little worse and you cause people to die. This isn’t an artifact — it’s based on the density of uninfected people when social distancing ends — but let’s just say “mathematical models are wonky” and leave it at that.)

In a subsequent figure, the Harvard team tried to model what might happen if we occasionally resumed our lives for a month or so at a time, but then had another shutdown.  This is the only scenario in which their model predicts that social distancing would be helpful.

But, unfortunately, there’s a problem.  Research done with other coronaviruses shows that immunity fades within a year.  Because the Harvard model would cause the epidemic to last longer than a year, people would have time to lose their immunity and get infected again.

Even in the extreme case that we mostly stayed in our homes for the better part of two years, social distancing would case more deaths from Covid-19 than if we had done nothing.

That’s not even accounting for all the people who would die from a greater risk of domestic violence, hunger, drug addiction, suicide, and sedentary behavior during the shutdown.  

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When our data was limited, the shutdown seemed reasonable.  We wouldn’t be able to undo the damage we’d done by waiting.

Except, whoops, we waited anyway.  We didn’t quarantine travelers in January.  The shutdown didn’t begin March, when the epidemic was well underway in many places. 

Now that we have more data, we should re-open schools, though.  For most people, Covid-19 is no more dangerous than seasonal influenza.  We already have enough data from antibody testing to be pretty confident about this, and even if we want to be extremely cautious, we should continue the shutdown for a matter of weeks while we conduct a few more antibody studies.  Not months, and certainly not years.

At the same time, we need to do a better job of protecting at-risk people.  This means providing health care for everyone.  This means cleaning our air, staunching the pollution that plagues low-income neighborhoods.  This might mean daily medical checkups and PCR tests for people who work closely with at-risk populations.

Our country will have to be different in the future, but mostly because we, as a people, have done such a shitty job of creating justice and liberty for all.  We need to focus on addressing the inequities that we’ve let fester for generations.  That’ll help far more than using a bandanna to cover up your smile.

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UPDATE: Wow, this got a lot of readers! Thanks if you made it this far. I’ve also written a response to common questions and comments about this essay.

On immunity.

On immunity.

Our efforts to “flatten the curve” of the Covid-19 epidemic are onerous. 

Children aren’t allowed to go to school.  We’re forcing small retailers out of business.  People aren’t hugging when they greet.

Some people think these sacrifices are worthwhile, though, if they reduce the number of people who die from Covid-19.

Unfortunately, the effort to “flatten the curve” can cause more people to die of Covid-19 — including more of our elders — than if we’d carried on with life as usual.

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Antibodies are like the memory of your immune system.  After you’ve been infected with a particular virus, your body can destroy further copies of that virus.

This memory doesn’t last forever.  Your body will “forget” how to fight off the coronavirus that causes the common cold within a year.

If we carried on with life as usual, the coronavirus that causes Covid-19 would probably make its rounds through the population of the United States within a few months.  After that, there would be no new people to infect, and so the virus would disappear.

If, however, we practice social distancing and slow the rate of transmission – the same number of infections spaced over eighteen months instead of eighteen weeks – your immune system has a chance “forget” how to fight off the virus while this virus is still circulating in the population.  By slowing the rate of transmission, you give yourself the opportunity to contract the infection twice

If we slow the rate of transmission enough, this coronavirus will survive indefinitely.  Then people will continue to die of Covid-19 forever.

Even if you are currently at risk — elderly or immunocompromised — you should still fear this possibility. Will you be less at risk when this virus hits your hometown again in another year?

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When a virus infects a cell, it uses that cell’s replicative machinery to make more copies of itself.  A virus can’t reproduce on its own – it can only co-opt its host’s cells into making more copies for it.

Each time the host makes a new copy, it must replicate the entire genome of the virus.  Our cells are pretty good at copying genomes – every time the cells of our own bodies divide, they produce a new copy of our 3-billion-base-pair genome, and the copies usually have only a handful of mistakes.

Of course, a handful of mistakes compounded over time can be deadly.  That’s what cancer is – your cells didn’t copy your DNA perfectly, and so you wound up with slightly mutated DNA, and this mutated DNA instructs cells to form a tumor that kills you.

The same accumulation of errors can change a virus.  In the 1918 influenza epidemic, huge numbers of people died because the virus mutated to become more deadly.

The longer we allow the Covid-19 outbreak to go on – the more we strive to “flatten the curve” – the more mutations will accrue in its genome. 

Consider a city in which ten people live, one of whom has the virus.  If they throw a party, the other nine will be infected all at once – they will all come down with the Nth generation of the virus, whatever the current sick person is shedding.  If, however, they practice social distancing and get sick one at a time, each passing the infection to the next, the last person in the chain will be infected with viral generation N+9.  It could be very different, and more dangerous, than the initial virus.

Mutation doesn’t always make a virus more dangerous.  It’s entirely random.  It was bad luck that a mutation in 1918 made that strain of influenza more deadly.

But the risk is real.  It’s a risk we aggravate if we “flatten the curve.”  Right now, very few young healthy people will be hurt by Covid-19, but no one can know what monstrosity we’ll produce if we allow this virus to cycle through enough generations.

Inconveniently for us, Covid-19 is caused by an RNA virus.  Our cellular machinary is pretty good at making copies of DNA – every round of cell division makes a few mistakes, but not so many.  Our cellular machinary is worse at making accurate copies of RNA.  A virus with an RNA genome will mutate faster.

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People are worried that, without drastic efforts to slow the rate of transmission of Covid-19, the influx of new cases would overwhelm our hospitals.  We might run out of ventilators and be forced to triage, providing heroic medical interventions only to those people most likely to survive.  Some number of elderly patients with a low chance of survival would not receive care.

Is this bad?

Most medical doctors have signed “do not resuscitate” orders.  I have, too.  Most medical doctors, who have seen over and over again what it’s like when elderly patients with a low chance of survival receive heroic medical interventions, don’t want it for themselves.  They would rather die in peace.

The New York Times – which, alongside the New York Review of Books, is my favorite news outlet, even though it’s been full of fear-mongering about Covid-19 – printed a quote from Giacomo Grasselli, who coordinates intensive care units throughout Lombardy, Italy.  Grasselli is working at the front-lines of the Italian Covid-19 outbreak.

“My father is 84 and I love him very much,” but it would be irresponsible, he said, to make him go through the invasive procedures of an I.C.U.

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In the United States, we spent over three trillion dollars on medical care in 2016.  A huge fraction of this spending is used for minuscule extensions of life.  A third of all Americans have surgery during their last month of life.  We often spend more on interventions that extend the life of wealthy patients by a month than we do on all the pre-natal, preventative, and acute care that other people receive, ever.

What’s been missing, in the United States, is a conversation about what constitutes a good life.  What needs to happen for people to be able to face death with the thought that their lives have been enough? 

Covid-19 has killed thousands of people who were privileged to live to extremely old age.  In the United States, the worst outbreak will be in New York City – a city that is so expensive to live in that it harbors huge concentrations of wealthy elderly people.

In the United States, the life expectancy is 78 years.  Of course, there are major inequalities.  If you are wealthy, you might live longer than that.  If you are poor, you’ll probably die younger.  My spouse’s parents both died in their 60s.

Covid-19 has a high mortality rate for people who have already exceeded this life expectancy.  For people under retirement age, Covid-19 is less dangerous than seasonal flu.

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In the United States, life expectancy has been falling.  This decline is primarily due to an epidemic of “deaths of despair”: Drug addiction.  Suicide. 

In the United States, around 40,000 to 50,000 people die of suicide each year.  Around 60,000 people die of drug overdose.  Around 70,000 people die from alcohol abuse.

Each year, the epidemic of “deaths of despair” kill somewhere between 100,000 and 200,000 people.

Our efforts to “flatten the curve” will probably increase the number of people who die from deaths of despair.

Small towns across the United states have been gutted by the internet.  People used to visit local retailers, which could employ local salespeople.  Then we switched to buying things on Amazon, giving Jeff Bezos our money instead.

Now, local retailers are being forced to close due to fears about Covid-19.  People have to buy things online.  But local retailers still have expenses.  They still have to pay rent.  The owners still have to eat.  Many small retailers will run out of money and never open again after the Covid-19 epidemic is over.

As if our small towns needed yet more punishment.

In general, people will experience more financial woes because of our response to Covid-19.  Businesses are closed.  Work has slowed.  The stock market has tanked. 

And financial instability increases the risk of deaths of despair.  That’s a major reason why there’s been such a dramatic rise in deaths of despair among young people.

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Thankfully, our efforts to “flatten the curve” aren’t guaranteed to make this coronavirus mutate.  Our efforts aren’t guaranteed to make this virus a permanent parasite on the human race. 

We might cause these calamities, but we don’t know for sure.

Indeed, we know very little about this illness.  We do know that tens of thousands of elderly people have died.  But we don’t know whether ten thousand died out of a hundred thousand who were infected, or a million, or tens of millions.

Our perception of the disease would be very different in each of those scenarios.  But we do not, and can not, know.  We have no retrospective testing, and we have never tested a random sample of the population to investigate viral prevalence.

The best we can do is estimate from small data sets, the way Stanford epidemiologist John Ioannidis has done.  Ioannidis is very clear about his methodology, so if you happen to disagree with any of his assumptions, you can re-work the math yourself.

He concludes that our response is a horrific over-reaction.

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The people recommending these policies – social distancing, school closure, stay-at-home orders, or total lockdown – aren’t doing so out of malice.  They’re making the decisions they feel to be best.  But no policy is neutral, obviously. 

These policies prioritize the short-term needs of wealthy people who have exceeded their expected lifespans, at the expense of everyone under retirement age.  In particular, these policies do not value the needs of children.

Many of our country’s policies prioritize the desires of wealthy older people over the needs of children, though  “Flatten the curve” is just another example.

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In many places, we are probably attempting to “flatten the curve” after the epidemic has already run its course.

More likely than not, I already had Covid-19.  In early January, a co-worker of my children’s best friends’ parent left China, stayed briefly with her daughter in Seattle, then returned to Bloomington. 

A few days later, she came down with a high fever and a bad cough.  She went in for a flu test, but tested negative.  The doctors sent her home.

A week later, my children’s best friends’ parent – the sick woman’s co-worker – came down with a high fever and a bad cough.  His children were sick enough that they stayed home from school for a day.  He was sick enough that he missed a week of work.

A week later, on February 10th, my children and I got sick.  We had a high fever and a bad cough.  The kids felt better the next day.  I felt wretched for an entire week.  I am an endurance runner with strong lungs – still, I needed puffs of my spouse’s Albuterol inhaler four times a day.  I took naproxen but still had a hallucinatory fever.  I wouldn’t wish that illness on anyone.  For the next two weeks, I was vigilant about washing my hands and tried to minimize my contact with other people.

Over the next month, many other people in town came down with a cough and fever.  It would typically last a week, then they’d feel better.

But it was pretty scary for some people. I’d felt wrecked. Another friend of mine — 55 years old, cigarette smoker, & former methamphetamine addict — felt like he could barely breathe. The doctor said that if his oxygen flow had been any lower, she would’ve kept him at the hospital.

He wasn’t tested for Covid-19. There were still no tests available. And after a horrible week, he felt better.

And then, on March 12thafter the epidemic had probably run its course in our town – our schools closed.  The university students left for spring break, and the remaining populace of our small town began to practice social distancing.

And yet, in mid-March, the first case of Covid-19 was diagnosed here.  This patient could not trace the social connections that would have led back to a known Covid-19 outbreak.  As should be expected by that late stage of an epidemic.

All around the country, reported Covid-19 cases are exponentially rising.  But that doesn’t mean that Covid-19 infections are exponentially rising.  It only means that access to Covid-19 testing has risen.

When the epidemic likely spread through my town, it went undetected – no Covid-19 tests were available in the United States, and there’s no way to test whether someone was infected in the past.  The reported numbers of Covid-19 cases are guaranteed to be lower than the true number of people infected, because you can only be counted as a Covid-19 if you feel sick enough to visit a doctor, and then somehow manage to get access to the test.

The test will only register positive during the acute phase of the illness.  There is no possible way to test whether someone who isn’t currently shedding virus has been infected.

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A useful way to consider this epidemic is to imagine what would happen if the Covid-19 PCR test wasn’t invented. 

People would still get Covid-19.  We would take no extraordinary protective measures, because we wouldn’t realize what they were sick with.

This is like what happened at the beginning of the HIV crisis in the United States.  Medical doctors called the disease GRD, or “gay-related disease,” and it was terrifying.  Healthy young people suddenly wasted away.

If we lacked a PCR test to accurately diagnose Covid-19, though, we wouldn’t call it “age-related disease.”  We would call it “seasonal flu.”  This year, about 30,000 people will die of seasonal flu, including many healthy young people.  This year, my nephew almost died of the flu.  He couldn’t breathe.  He needed invasive ventilation to survive.

If we did nothing to staunch the Covid-19 outbreak, somewhere between 15,000 and 30,000 people probably would die from it.  Combined with the 30,000 deaths actually caused by influenza, we would think that between 45,000 and 60,000 people had died from seasonal flu.  No more than a dozen or so of the additional deaths would have been healthy young people.

That’s many more deaths!  But nothing exceptional.  In 2017, 60,000 people died of seasonal flu.

In 2017, we still let children go to school.  I’m not sure I read any news articles about seasonal flu in 2017.  And in the following years – after huge numbers of people died! –  about half our population didn’t bother to get a flu vaccine.

Influenza is a more dangerous illness, and it’s preventable.  But our country’s vaccination rate is too low to confer herd immunity.  Even if you are young and healthy, a bad case of the flu can kill you.  Even if you are young and healthy, your vaccination protects others.

Social distancing would protect people from the flu, also.  Every flu season, we could stay six feet away from each other for a few weeks, and then we’d vanquish the flu.  But social distancing comes at a tremendous cost, as we’re now learning.

Or we could get the vaccine.  But we, as a people, don’t.

On wasteful medical spending.

On wasteful medical spending.

Given that our bizarre medical spending practices could doom the U.S., it feels strange to write about this topic as a participant-observer.  So let me state upfront: I tried!  I argued with my medical care providers for several minutes, trying to keep them from wasting money.  I used logic.  I cited evidence.  I lost the argument.  They stuck to their position with the unwavering intransigence of bureaucratic rule-followers.

They were probably right to ignore me.  If a bigwig in a suit writes guidelines saying, “Do it this way,” a nurse or doctor might be fired for doing things differently.

marktsedita-MUMPS
Art by MTS<:U on Flickr.

The background: many people in my hometown recently contracted mumps.  Those who work with young people were instructed to get a “mumps titer” — this means measuring the concentration of mumps antibodies in a person’s blood — and those with low readings would be told to get vaccinated.

Sounds sensible enough.  But the titer is more expensive than the vaccine, and we have the vaccine in abundance, so I went in and asked them to just vaccinate me.  Yes, I was vaccinated already as a child, but it doesn’t hurt to get a booster.

They refused.  It’s a live vaccine, see?  To vaccinate you, they inject the actual virus.  The goal is to produce a “subclinical infection.”  But some adults have an adverse reaction — they get sick.  To minimize risk, our health care provider wanted to vaccinate only those people who seemed to need it.

The problem with this logic is fairly clear — although some people may get sick from the vaccination, the people who get sick are going to be those who were not yet immune.  By screening people with high titers, the total number of patients suffering an adverse reaction won’t go down at all.

The faulty logic would be problematic even if the mumps titer was a good assay.  But it’s not.  It’s fairly well known that it produces many false negative results — people who appear not to be immune to mumps, but are.  According to my health care provider’s policy, many people who are already immune to mumps will be vaccinated again.

This is fine from a health perspective, of course.  A second immunization will not hurt.  These people are very unlikely to get sick from the attenuated virus.  The only problem is that money was wasted on the titer.

Worse, common titer assays have a fairly high false positive rate: that is, people who appear to be immune, but aren’t.  Under my health care provider’s plan, these people won’t be vaccinated.  Now, these are people who might get sick from the vaccine — but they’d get much sicker if exposed to the actual virus.  If they’re not vaccinated, they’ll be left at high risk.

800px-Study_Participant_Receives_NIAID-GSK_Candidate_Ebola_Vaccine

Compared to simply vaccinating everyone, testing everyone by mumps titer costs somewhere around twice as much.  Add in the number of vaccines that have to be given after the tests and the plan is even more expensive — even if everyone in the population already is immune to mumps and you’re only giving booster shots to those with false negatives, that could easily be twenty percent or more.  If you’re dealing with a mixed population where some people aren’t immune, the outlook is worse.  Then you’re also risking that someone with a false positive result, whom you decline to vaccinate, gets sick.  Mumps can make you very sick, especially adults.  It can cause brain inflammation — my father, who contracted mumps as a child, needed a spinal tap to get through it.  A scary procedure.  Much more expensive than the vaccine.

(Well, a spinal tap now is much more expensive than the vaccine now.  For my father to have been vaccinated, someone would have had to build a time machine and launch the shot into the past.  Time travel takes huge amounts of energy & is rather more expensive than a spinal tap.)

Nobody at my health care clinic was convinced.  They were adamant.  No vaccine without phlebotomy!

At least the universe has a sense of humor.  After all that, of course my titer would be a false negative.  Their money wasted, they called me back and had me get the unnecessary shot.  Just like I’d requested from the beginning.