TWiV 590: COVID-19 and coronavirus – we have mail

March 8, 2020

The TWiV trio continues in-depth coverage of COVID-19 and SARS-CoV-2, including discussion on genome mutation and circulating lineages, handwashing, facemasks, cruise ship outbreaks, the South Korean situation, and much more.

Hosts: Vincent Racaniello, Rich Condit, and Kathy Spindler

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Intro music is by Ronald Jenkees.

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26 comments on “TWiV 590: COVID-19 and coronavirus – we have mail

  1. Hi twiv! I love your coronavirus podcasts and listen to them while doing experiments…I would like to just suggest that we should stop referring to studies carried out by Chinese authors as “Chinese studies”. Why is that adjective necessary to understand the science behind it? You do not refer to a study as an “American study” unless it is e.g. a cohort study using American subjects. This is the only case where I would find this acceptable, but even then it could be worded differently, such as: a study with subjects based on country X. Anyway, I hope this is constructive and can allow us all to be less biased/discriminatory regarding the authors . Keep these podcasts coming!

    • profvrr Mar 8, 2020

      I do agree with this sentiment, which I have heard often. However please understand that sometimes, while summarizing a paper or commenting, especially on a podcast, one forgets to be proper. I assure you it it not intentional.

  2. There’s a difference between “soaps” and “detergents.” Also, there are two relevant properties I can think of – as a surfactant (releasing bacteria from surfaces, allowing them to be flushed away by water during washing), and as amphiphiles (which, coat bacteria, inhibiting life processes).

    PS: with regard to N95 masks, the wisdom comes from Quammen’s Spillover which quotes the use of N95 with SARS-1. (I realize that’s not a controlled experiment.)

    • profvrr Mar 8, 2020

      Thanks for the clarification. I don’t consider Spillover a definitive source of controlled experiments, I would like to see the journal article.

  3. Thank you so much for your discussions!!!

    Just a comment (apologies for belaboring!): N95, N99, and N100 masks incorporate significant advanced technologies in the micro-aerodynamic construction/arrangement of filter fibers for efficient trapping of sub-micron particles. These technologies aren’t present in surgical masks, which are just a cloth – so it would be hard to rationally argue that they aren’t significantly better than surgical masks at stopping infectious aerosols in the transmission of sars-2 (of course, the big caveat is “proper usage” – as a USAF/SMC scientist I was often re-trained in the use of these as part of the standard laboratory safety regimen). Since we’re entering a pandemic age, this seems to be something to pursue for large, dense populations, although I agree that improper use by the lay public – which is itself endemic – likely renders them much less useful than they would otherwise be. Perhaps public information campaigns may ameliorate that somewhat, and at a relatively low price. Most unfortunately, the heaps of used masks (medical waste) piling up in China may be a significant argument against the widespread use of masks given limited planetary resources and pollution-sinks.

    I’m sorry for the comment about the importance of GDP, but from what I read by US medical researchers, it is generally understood that GDP is what enables modern medical technologies (or the lack of them in the case of antibiotics).

    • profvrr Mar 8, 2020

      The one paper I read compared surgical masks with N95 in nurses and found no difference in rate of influenza infection. Not a great paper in my opinion because there was no un-masked control.

  4. Mark O Martin Mar 8, 2020

    Dear Vincent and fellow TWiVvers…

    My campus at the University of Puget Sound in Tacoma, Washington has moved to “virtual” lectures next week. So I will be using Zoom to “narrate” my lectures—I can’t be as entertaining and informative as you and your cohosts.! Wish me luck on the coming week! I think the idea is to reduce student numbers in an enclosed area.

    At the same time, I know that many students are happy (thinking classes have been canceled). I am encouraging people to avoid crowds (for the reasons of transmission), to wash hands according to the new reality, and disinfect areas regularly. I’m hoping that the students at parties are doing the latter—I cringe, thinking of the party games I played as a youngster, like beer pong or flip cup. Hopefully this generation is smarter than my own.

    I have made your podcasts available to my first year and upper level students. Heck, I made them available to my faculty! I am sending a copy of Carl Zimmer’s “Planet of Viruses” and links to TWiV to our university President and current Faculty Provost. Your calm and considered words are important, trust me!

    As for microbes on bar soap, I would guess that the microbes found are living on the “scum” that soap tends to develop. I doubt that they are living on the actual surface of the solidified detergent! But—the microbial world is nothing if not tenacious. We should talk about reusable water bottles and microbes sometime.

    Anyway, I wanted to thank you all for your very, very important contribution to helping me explain the situation in my classes. I am going to bump up my Patreon contribution!

    Thank you, Mark Martin

    • profvrr Mar 8, 2020

      Thank you Mark. I’m glad the podcasts are useful in clarifying this epidemic. We do work quite hard to try and find useful information and then talk about it. And thanks for the comments on soap vs scum.

  5. Cameron Rogers Mar 8, 2020

    Hi Twiv team,
    I can’t believe how authorities around the world have been so slow to respond to SARS-CoV-2. We had ample warning from seeing the situation evolve in China but at least here in Australia, we are still waiting for the virus to really hit us before responding. Last night they had the women’s T20 (cricket) final in Melbourne, it was a new Australian record at a women’s sporting event with 86,174 according to the official attendance! How about using some social distancing? It seems that it is common for many authorities around the world to wait until they can’t control community transmission before they respond!

    A pandemic of this nature doesn’t come as a surprise, the poor response from authorities is what has shocked me!

    Thanks for your wonderful podcasts, I wish they would put your team in charge of handling this outbreak!


  6. V/R = Very Respectfully

  7. scott christensen Mar 9, 2020

    hi, I’m an american living in Hong Kong, so can add some input on the discussion of control measures here.

    At the end of the chinese new year holiday, the government needed to let 200,000 people return from family holidays in mainland china, before tightening border controls, so we had an initial scattering of imported cases about a month ago.

    However as a city that still has a strong memory of the SARS epidemic, I can see that from January about 95% of the population is wearing surgical masks all the time. Most offices also started a work from home policy, which helped social distancing a lot. Washing hands and/or alcohol wipes is highly followed, with many people going as far as using tissues to open doors.

    It all seems to be working amazingly well, as the only community outbreaks have been in a few cases of subgroups of people that are not following the hygiene rules. Recent examples are a group of people that spent hours together at an indoor Buddhist temple, as well as a mass infection of 10 people at a hotpot restaurant.

    Oddly there was a well publicized case of an infected policeman, that had an all night dinner banquet with 50 of his colleagues who were quarantined, but no one was infected. The super spreader events are quite unpredictable! mysterious.

    An expat doctor was in the media last week, saying it would appears that extended very close indoor contact of 15 minutes or longer is involved in virtually all cases here. (there must be something unique about the Diamond Princess and other mass infections we’ve seen, and perhaps a lingering environmental source in wuhan?)

    • scott christensen Mar 9, 2020

      on the other hand, the city is “open”, the shops and many offices are operating, and people are out and about, and even the restaurants are about 1/2 occupied.

    • Another consideration for HK’s tolerance of the disruption to daily life required by strict social distancing is that Hong Kongers had been living in a state of disruption for the better part of a year already – so what’s a little more. I wonder if things would have played out differently if this had popped up a year or two earlier; would there have been a reticence to acquiesce to the disruptions?

  8. Terry Jones Mar 10, 2020

    Hi. Thanks for the episode. One point is that 9 mins in:

    * 80% of cases are mild/moderate (but 10-15% of these become severe). So that’s another 8-12% added on to severe.
    * 15% are severe (and 15-20% of these progress to critical) so that’s another 2.25 to 3% added on to critical.
    * 5% are critical.

    I.e., that’s actually 23-35% that are severe or progress to severe, and 7.25-8% that are critical or progress to critical. In total, that’s 30.25 to 43% that are either severe or critical (or progressing to). Those numbers appear to be way higher than the reality.

  9. Paul Akela Lucas Mar 10, 2020

    Just amazing discussion, let me know how I can support.

  10. Elizabeth Hovey (huvey) Mar 11, 2020

    Dear TWIV-gurus,
    Under no circumstances is this letter worthy of being read aloud on the podcast.
    I’ve been extremely happy to be a listener to TWIV since January, looking forward to filling out the poll here and for TWIM, which I have listened to longer.
    I’m getting tired of telling people that they would be more comfortable if they knew what you’ve shared, and giving the link to the podcasts. It’s delightful news that there were volunteer transcribers of a podcast or two and wonder if that is going forward or needs help*.

    I happen to teach at the campus of the ~14K students in Manhattan that last night announced a student (last on campus, for one class only on Thursday evening, symptoms on Saturday). I would like to find when/where you discussed the latest science of the range of asymptomatic contagion, but I am sure that it is well below the 14 days that my colleagues are focused on.
    I checked in with my son, the microbiologist who turned me onto your TWIM, who thinks one scientific consensus has been established, “everyone knows that the only thing we have to fear is fear itself.” ** In that respect the posting of infectious disease specialist Dr. Abdu Sharkawy of the University of Toronto is especially apt. He is my hero, and it is because of my knowledge from TWIV.
    I gave the equivalent of a year’s monthly $2 donation a short time ago. It would be monthly, but I resist paypal.

    Elizabeth Hovey
    Adjunct and Faculty PSC (Union) Chapter Chair
    John Jay College of Criminal Justice

    *Putting myself through Columbua graduate school (history) as a word processor in the ’90s, I still think I could be an asset, and I imagine myself listening to everything again anyway.
    **Not that president #45’s pronouncements ever influence me.

  11. Sorry in advance for all the posts – security breach at live coronavirus map:

  12. Why is the Johns Hopkins “dashboard” FUBAR? Confirmed cases dropped by 75% yesterday?

  13. Bill Benson Mar 14, 2020

    some decades ago great effort was made to recover tissues infected with the 1918 flu with the hope of discovering why it was so virulent. Did they ever find out? Can or could this be discovered for covid-19?

  14. Dear Twi’ers: Could you briefly discuss the difference between specific covid-19 “tests” (perhaps also known as “test kits”) and PCR? Apparently PCR can be used as a fairly reliable test for (systemic?) exposure to sars-cov-2, but is not sanctioned by the FDA, etc.:
    If “test kits” have to be manufactured, the delay in doing so (weeks) can have a severe impact on the outcome of a pandemic landing in the US. PCR, on the other hand, appears to be readily available – when I had influenza-B and a cold a couple of years back, it was used quickly and easily in my town of Prescott, AZ – a rather small town with no trauma center. (Perhaps you could mention the reply in your class, as that occurs more often than TWIV.)

    Thank you also for your classes! They have been wonderful over the last several years since I discovered them!

  15. Benedikt Klotz Mar 16, 2020

    Hi Twiv Team, thanks for the great discussions and information you share in your podcast. I highly appreciate the insights you share, although I do not have a background in biological virology.
    I do have a couple of questions which I would like to share with you. Where shall I post questions or what is your preferred channel of communication? There is a #TWiV Hashtag in Twitter. Do you monitor this?

  16. Joseph Stukey Mar 25, 2020

    Hi all,

    I was listening to episode 590 this afternoon (Wed. March 25) on my daily dog walk and heard an interesting question from a young listener on the topic of immunity generation to SARS-CoV2 and its mutation rate, and it stimulated and idea and this follow-up question.

    I was wondering if you know whether there are any plans to survey the recent health histories (over this COVID-19 epidemic time window) of individuals who were confirmed to have had the first SARS-CoV of 2002-2003 and who may have been exposed to SARS-CoV2? I do not know how many people that could be (if any?), given the outbreaks occurred in different provinces and the population size of China, but if there is a sufficient number of individuals, could it inform us on the quality of immune response to SARS-CoV in humans?

    I realize I am writing in several weeks late and so if my question has been asked or is not really relevant to the current conversation, please just ignore it.

    Have enjoyed the podcast for several years now and hope I will for many more.

    Thank you.