How Did COVID-19 Start?

 

Nearly two years after the initial fatalities that would turn out to be caused by the COVID-19 virus, we still do not know the answer to that question.  But last week, the U. S. National Institutes of Health revealed that it was funding "gain-of-function" research on bat coronaviruses in Wuhan during 2018 and 2019, in direct contradiction to Dr. Anthony Fauci's testimony before Congress that no such research was being supported by NIH there. 

 

In times past, plagues were regarded as simply acts of God, and while people tried to avoid transmitting infections by means of quarantines and travel restrictions, it was rarely possible to pinpoint the exact time and place where a given pandemic began.  But with advances in genetics and biochemistry, infectious agents can often be tracked down and successfully traced to their source, as was done with a localized outbreak of what came to be known as Legionnaires' disease, when it was traced to bacteria harbored in an air-conditioning water system.

 

By all measures, the COVID-19 pandemic has been the worst plague in modern times in terms of economic and social disruptions, casualties, and deaths.  According to the website www.worldometers.info/coronavirus, COVID-19 has been responsible for about 4.9 million deaths worldwide so far.  If for no other reason than to learn from our mistakes, it should be an urgent global priority to discover how the pandemic started, and whether it was by accidental transfer from an animal species such as bats to humans, or by means of deliberate creation of more aggressive viruses than occur in nature and accidental spread from the laboratory that created them.

 

Unfortunately, the COVID-19 pandemic started in a country that has systematically suppressed the information that would help in deciding this question.  But the following facts are known.

 

Shi Zhengli, a viral researcher at the Wuhan Institute of Virology, has worked for years with viruses taken from wild bats, as bats have the peculiar ability to host a wide variety of viruses that can be harmful to other species without themselves becoming ill.  To perform this research, she and her colleagues traveled far and wide to collect samples from bats in remote caves in other parts of China.  She has continued to perform research connected with COVID-19 in China after the pandemic began, and denies that there has ever been an accident in her institute resulting in infection of staff or students. 

 

Wuhan is by all accounts the city where COVID-19 first claimed its victims.  It is the largest city in central China with a population of about 11 million.

 

As we now know, the NIH funded so-called "gain-of-function" research through an organization called EcoHealth Alliance, headed by researcher Peter Daszak, which was conducted in association with the Wuhan Institute of Virology.  Gain-of-function is a bland phrase that means an infectious agent has been enhanced in its ability to infect a host.  While some argument can be made that concocting such viruses is the only way to figure out a defense against them, it is obviously an extremely dangerous thing to do.  Dr. Zhengli admits that prior to COVID-19, much of her viral research was done in lab conditions that were less safe (so-called "BSL-2" and "BSL-3") than the highest-security BSL-4 labs.

 

Let's imagine a different scenario and ask some questions about it.  Suppose nuclear weapons had not yet been invented, but researchers were hot on the track of cracking the secret of nuclear energy.  Suppose also in this contrafactual fantasy world that the U. S. funded some of this research at a center in Sao Paolo, Brazil.  Suddenly one day, a huge explosion happens in Sao Paolo, wiping it off the map and sending radiation into the air that eventually kills a total of 4.9 million people worldwide.  Despite the fact that most of the relevant data to determine the exact cause was vaporized in the explosion, wouldn't it be wise at least to do our very best to figure out what happened, with or without the cooperation of the Brazilian government?

 

In a sense, we already know what to do.  Whether SARS-CoV-2, the virus responsible for the COVID-19 pandemic, actually originated in a lab accident in Wuhan or in an exotic-food market there, we now know that early detection and faster responses to highly contagious new diseases might make the difference between another world-crippling pandemic and a minor contained outbreak. 

 

In the case of COVID-19, the Chinese government delayed for weeks before even publicly acknowledging the magnitude of the problem, and criticized brave medical workers who tried to publicize the seriousness of the nascent epidemic.  In retrospect, this was exactly the wrong thing to do, but it is the natural response of most governments to minimize something that is not yet so obviously awful that denials will look silly. 

 

One hopes that if a similar outbreak happened in, say, Chattanooga, state and federal officials would be more forthcoming than their Chinese counterparts in telling the rest of us about what was going on.  As to the measures that would have stopped the epidemic in its tracks, it seems that only a city-wide 100% quarantine with extreme measures taken to enforce it would have worked, and maybe not even then.  Any government will be reluctant to impose such a draconian measure unless there are very good reasons to do so. 

 

But as things stand, there are still unanswered questions about what other activities EcoHealth Alliance was doing in China that they were supposed to report on but didn't.  Unless the Chinese government suddenly becomes more forthcoming about what really happened in Wuhan, we may never know how COVID-19 really began.  But we certainly know how it spread.

 

In investigations of engineering disasters, future accidents of a similar nature can't reliably be forestalled until the exact mechanism of the one under investigation is understood.  We have part of the picture of COVID-19's origins, but not the whole story.  The best we can do now is to be much more aware of rapidly spreading fatal diseases in the future, and willing to take what may look like extreme measures locally to prevent another global pandemic. 

 

Sources:  National Review carried on its website the article "The Wuhan Lab Coverup" at https://www.nationalreview.com/2021/10/the-wuhan-lab-cover-up/.  I also referred to the NIH letter at https://twitter.com/R_H_Ebright/status/1450947395508858880 and the Wikipedia article on Shi Zhengli. 

Are Immunity Passports In Our Future?

Here in the midst of the COVID-19 crisis, many of us are starting to wonder how it's going to end.  Just last Friday, Texas Governor Greg Abbott announced plans to lift certain restrictions related to the pandemic.  Regardless of what governments do, the big question people have is not so much what's happening to the economy in general, but this:  "When can I safely resume my normal way of life?" 

Some people never stopped working—notably many healthcare workers, first responders, and employees of essential businesses such as grocery stores.  But they have kept working while trying to protect themselves from the virus, and that doesn't always succeed.  For example, numerous meat-packing plants across the U. S. have shut down because of the spread of COVID-19 among their employees, despite the strict microbiological protocols that such packing plants have to observe. 

Wouldn't it be nice if there was a simple, cheap, fast blood test to tell if you have the SARS-CoV-2 virus that causes COVID-19? 

Lots of pharmaceutical companies around the world have rushed into production just such devices, referred to as point-of-care antibody tests.  Many of these are what the specialists call "lateral-flow assays."  You get a drop of blood from the patient and put it on an enclosed test strip.  As the serum flows along the strip it encounters some stuff that changes color if the blood sample has the specific antibodies that the virus in question provokes the body to make.  And a final strip turns color to verify that the stuff got that far, as a reliability check.  The whole thing takes only 15 minutes or so, and the tests can be mass-produced for as little as $3 each.

Already, governments and institutions around the world are using these antibody tests for finding out who has antibodies.  They are not intended to be used to diagnose COVID-19, however.  It takes your system a week or longer after infection to develop enough antibodies to show up on an antibody test.  So you can be walking around with COVID-19 and infecting other people, and still test negative on an antibody test.  The gold standard for having an active infection is still the laboratory-based polymerase-chain-reaction (PCR) test, done typically with a nose-swab sample that is sent to a high-tech lab, although there are point-of-care versions of PCR tests now available as well. 

But the test that is generating the most interest is the antibody test.  Presumably, a person with enough antibodies against COVID-19 is immune, although the truth of that assumption is actually still a research question that is currently being investigated.  As if that wasn't complicated enough, there are neutralizing antibodies, which confer long-lasting immunity, and binding antibodies, which just fight short-term infections.  Most of the point-of-care antibody tests detect only the binding antibodies, which indicate that you've been dealing with the virus recently.  Most people, but not all, go on to develop the neutralizing antibodies that confer immunity, but for how long, nobody knows yet.

Okay, so say I'm a manager desperate to get my factory back into production, and somebody comes along and offers me an antibody test.  I will be strongly tempted to require all of my workers and prospective employees to take the test, and only allow in the ones who test that they are immune.  Right now, that might not be a large percentage, but as time goes on and the hoped-for "herd immunity" develops, such a testing policy might be very tempting.  In effect, you'd have to have an immunity passport in order to go back to work.

Already, many health care institutions are planning to administer antibody tests, with the assumption that anyone who tests positive can't get COVID-19, or is at least much less likely to catch it, and so they might be the people you put on the front lines dealing with COVID-19 patients, reserving your non-immune staff to safer duties.

And let's get personal here.  What about teachers or others who deal with large numbers of people in close proximity?  When I was hired at Texas State University, I had to show that I passed a TB test.  That was to make sure I didn't have tuberculosis, which can be a chronic asymptomatic disease that can nevertheless be spread by otherwise apparently healthy people. 

With COVID-19, it's sort of the opposite problem.  Without a vaccine (and most experts think that's at least a year away), the only way you can safely start being in proximity with strangers on a routine basis is if most of the other people around you can't get COVID-19.  That's what herd immunity means, and we don't really know how far away from that we are, without widespread antibody testing of representative samples of the population, both apparently healthy and otherwise.

That's probably the best current use of antibody tests:  to monitor the average state of immunity in a geographic area with random sampling of both healthy and sick people.  That way, even if the tests aren't 100% accurate (and many of them fall short of that), you can factor the errors into statistics and still arrive at a pretty good aggregate number, and it doesn't matter if the odd result here or there is wrong.  In particular, it won't condemn to continued unemployment a person who has really had COVID-19 but the antibody test wrongly says he or she hasn't had it. 

A perverse situation might arise in which those of us, especially ones over 60, who have gone to extraordinary lengths to avoid catching the stuff, end up being sort of inverse Typhoid Marys.  Our employers might say, "Look here, I'll take back people who have had it and can't catch it, but you susceptible folks, you'd better stay away for a while longer until the herd immunity gets so high that it's unlikely you'll catch it regardless."  Maybe not every employer will think that way, but some of them will.

At this point, it looks like the antibody tests are simply not reliable enough to do such specifically targeted testing, especially if the results can mean continued unemployment or worse.  But look for problems to crop up along these lines, and where such problems show up, lawyers can't be far behind.

Sources:  I referred to an article on the website of the Journal of the American Medical Association by Jennifer Abbasi at https://jamanetwork.com/journals/jama/fullarticle/2764954.  The meat-packer shutdown is described at  https://abc7chicago.com/health/covid-19-outbreak-at-chicago-meat-packing-plant-sparks-calls-for-investigation/6114075/.

Peter Tsai and the Electrostatic Filter Mask

Every now and then, and especially in distressed times such as these, it's good to spotlight an engineer who has done the right thing, and keeps doing the right thing.  Today I'm going to do that with Peter P. Tsai, who is credited with inventing the electrostatic non-woven filter used in the N95-type disposable masks that are such a hot topic nowadays. 

In 1995, Prof. Tsai was a materials scientist working at the University of Tennessee in the area of non-woven filter materials.  Air filters have been used for many decades to separate undesirable particles from air.  If the particles to filter out were large, almost any finely woven material whose openings between the threads were smaller than the particles could catch them.  But many of the most objectionable particles, such as tiny smoke particles and virus particles, are smaller than one micron, which is one millionth of a meter.  Just to give you an idea, a human hair is about 25 microns or more in diameter.  So we are talking very, very small.

It's almost mechanically impossible to weave cloth with fibers that are smaller than human hairs, so filter designers looked around and discovered that a mat or mesh of non-woven fibers was more effective than any woven fiber could be.  The tortuous pathways a particle has to take through the random labyrinth of a non-woven mat of fibers makes it more likely that the particle will get caught somewhere before it makes its way through the filter. 

But even with non-woven materials, there was a tradeoff between effectiveness and how hard it was to get air to go through the filter.  The thicker a filter is, the more likely it is to catch particles, but the harder it is to get air to go through it.  This problem can be fixed by making the area of the filter wider, and that is done in stationary systems such as air conditioners.  But you can't attach a portable mask to a foot-square air conditioning filter.  So there was a quandary and it looked like there weren't a lot of new ideas to make small filter masks more effective for very small particles like viruses.

At this point Prof. Tsai, and others preceding him, took a hint from the industrial filter technology known as electrostatic precipitation.  Electrostatic precipitators use high electric fields to charge dust particles and attract them to highly-charged wire grids, where they are trapped and disposed of.  They work well, but they are huge structures attached to factory chimneys and require high-voltage power supplies. 

Prior to Prof. Tsai's work, others had thought of the idea of making the plastic fibers in a non-woven filter electrified through a process known as hot charging.  When the fibers were still in a halfway-liquid form right after they are spun from a melt, it is easy to put an electric field on them that "freezes" into the plastic.  But the charging-while-hot process was tricky and probably expensive.

Prof. Tsai's innovation was to find a way to take a cold pre-fabricated mat of non-woven material and subject it to two electric discharges of opposite polarity, one after the other.  Under the right conditions, this process embedded quasi-permanent electric charges into the plastic fibers and made them very attractive to even sub-micron particles, like the 100-nanometer-diameter SARS-CoV-2 virus that causes COVID-19.  The charge is durable and will persist even if the masks are sterilized with steam, according to a new article that Prof. Tsai just put up on a University of Tennessee website.

After a career in which he obtained 12 patents and many commercial licensing agreements for his university, Prof. Tsai retired recently, but he came out of retirement to write the article I referred to, which tells health care workers how to reuse scarce N95 masks and what methods will and won't work to sterilize them without spoiling their electrostatic properties.  Another article about his work estimates that over a billion people have benefited from using masks that employ his invention of cold-charging nonwoven fibers.

Humility is not something that today's culture looks upon favorably.  The media that get the most attention these days are constantly highlighting people who use institutions as platforms to further their own fame and glory.  Even some engineering and science types (Elon Musk comes to mind) go this route and strive for public recognition, fame, and the perks that go along with these things.

Peter Tsai is not a limelight kind of guy.  A brief biography of him on the University of Tennessee website points out that he has had many opportunities to take more prominent positions, but he has stuck to his laboratory and continued to produce inventions right up to his retirement.  I don't know this for a fact, but it's quite possible that Prof. Tsai is an introvert—someone who is more comfortable working alone or with a small group of carefully chosen colleagues than he is speaking to a huge crowd at a conference, for example. 

As Susan Cain points out in a book of hers I've begun to read (Quiet:  The Power of Introverts in a World That Can't Stop Talking), much of American society is set up to favor the talkative, sociable extrovert and to view the introvert as weird or sad or even anti-social.  But introverts can do things that other kinds of people have trouble with—for instance, studying a dull materials-science problem for years until insights and hard work pay off with an innovative technique such as cold-charging nonwoven fibers. 

For two or three decades now, academia in general and engineering in particular has emphasized teamwork almost to the exclusion of allowing people to do work on their own.  I'm sure Prof. Tsai had help in doing what he's done with filter-mask materials, but I hope he'll allow me to use him as an example of what the non-attention-getter type of engineer can achieve.  By and large, he has let his work speak for itself, and now that is paying off in the lives saved, especially among medical workers, who would otherwise have inferior filtering and higher risk for contracting COVID-19.  If you are one of the lucky people these days with access to an N95 mask, take a moment to thank Prof. Tsai and his colleagues for coming up with the ideas that make such things possible.

Sources:  An article describing Prof. Tsai's work on cold-charged electrostatic non-woven filter material is on the University of Tennessee website at  https://utrf.tennessee.edu/ut-researchers-nonwoven-fabrics-protect-the-health-of-more-than-a-billion-people/.  Prof. Tsai's own article describing effective sterilization methods for the masks is at https://utrf.tennessee.edu/information-faqs-performance-protection-sterilization-of-face-mask-materials/.  And the U. S. patent for cold-charging non-woven materials that Prof. Tsai obtained in 1995 is No. 5401446, which can be viewed on Google or the U. S. Patent Office site.