TWiV 648: Life is for learning

August 2, 2020

Daniel Griffin provides a clinical report on COVID-19, followed by a review of the findings that children shed as much SARS-CoV-2 viral RNA from the respiratory tract as older patients, the lineage giving rise to SARS-CoV-2 has been circulating in bats in China for decades, and answers to listener questions.

Hosts: Vincent Racaniello, Dickson DespommierAlan Dove, Rich Condit, and Brianne Barker

Guest: Daniel Griffin and Chuck Knirsch

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Download TWiV 648 (105 MB .mp3, 175 min)
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Intro music is by Ronald Jenkees

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27 comments on “TWiV 648: Life is for learning

  1. Len Berman Aug 2, 2020

    Inexpensive tests are not profitable, therefore no cheerleaders for cheap tests. Sad world.

  2. Tim Escher Aug 2, 2020

    Just discovered UCSF Grand Rounds about COVID status. Lots of great data in here about testing and infectiousness. Highly recommended.

  3. Patricia Aug 2, 2020

    Greetings to you all and thank you for giving your time to make the podcast.

    I enjoyed your review of the scientific paper and called it up in another window so as to be able to read during the discussion.

    My degree is in French (so only high school science background), but I have followed
    Vincent’s 2020 virology course and try to keep up!

    Here in Britain all bat species and their roosts are legally protected – given all that is know about the bat as a viral reservoir, it time for the use of bat guano (unless it can be treated) and the disturbance, trapping, butchering and consumption of bats to be banned under international law?

  4. Ole Bjørsvik Aug 2, 2020

    Beautifully wriiten letter from Mark to his governour. I would not be able to write somethin like that without inspiration.

  5. The article mentioned at 17:40 showing benefit for the wearer:

  6. chris kaiser Aug 2, 2020

    At 9:04, concerning so called “cheap, rapid tests” when will the government get the message and implement usage of these tests.

  7. Jon Duvick Aug 2, 2020

    Hi Vincent great podcast! Can you add a hyperlink to the Nature Microbology paper you discussed: Here it is:

  8. Lani Teshima Aug 2, 2020

    Amy Schumer, according to wikipedia, is Chuck Schumer’s cousin, not his daughter.

  9. Caren Aug 2, 2020

    My god you guys, the answer isn’t writing your senators carefully crafted letters – you need to get Minna on Joe Rogans podcast.

  10. Virginia J. Rasch Aug 2, 2020

    Can someone with mild symptoms from COVID-19 have serious short- or long-term health consequences?

  11. David Smith Aug 2, 2020

    Regarding rapid tests especially in school-like settings, wouldn’t the requirement for a machine – any machine – be a show stopper? The ones I’ve looked up don’t parallel process, so maybe I’m missing an option there. The back of my envelope high level math says just 300 kids showing up for 300 tests, each taking 20 minutes means you have all of the results in about 4 days. If you ship them all to a local lab do they really have dozens of these machines? One more wrinkle, at least in the AbbotID NOW documentation the sample must be processed immediately, very little latitude for storage or transportation. Would they all have that limitation? I’m thinking it’s paper strip pregnancy-type tests or nothing folks.

  12. Greetings & Salutations from Powys, Wales.
    (18 degrees C )

    I love the podcast and have not missed an episode since March – it’s wonderfully informative and entertaining.

    However it is with a heavy heart that I have to bring down the pedant hammer: IT WAS GATORADE! (According to Last Podcast on the Left anway)

  13. As usual, great and informative discussion. Thank you for all of your efforts to educate us.

    On TWiV 648 Dr. Griffin talked about a table he made, but to the best of my knowledge didn’t show the actual table. I tried to reconstruct it from the episode and wound up with this: It would be great to see Dr. Griffin’s table.

    Thank you again for the great work.

    • Luke Kruse Aug 4, 2020

      Thank you for commenting this, I logged onto the website to ask for it!

  14. Jon Duvick Aug 3, 2020

    Hi Vincent can you add a hyperlink to the Nature Microbiology paper? It’s

  15. Jon Duvick Aug 3, 2020

    Regarding rapid COVID tests, I see that Dr. Sehault of MedCram will be interviewing Michael Mina on Wednesday Aug 5 on YouTube Live with questions culled from listeners.

  16. Leonard Berman Aug 3, 2020

    Watching Gov Cuomo talking about school opening and not mentioning $1/spit tests. Does he watch TWiV?

  17. Robert L. Colvard, Jr Aug 3, 2020

    Dear Dr. Racaniello and friends. Love your show sooooo… much, especially when you stick to the science. However, I have a question about masks. I have been researching face masks that are readily available to the general public. According to face masks have pore diameters ranging from 80-500 micrometers, but the SARS-CoV-2 virus has a diameter 100 nm. That means that the pores in the masks are 800-5,000 times bigger than the virus. Additionally, I have noticed that when I am wearing my mask that cigarette smoke is not blocked. I have discovered that exhaled cigarette smoke particles range from 220-300 nm (( and ( Can you explain why you think masks are such an effective measure against the spread of COVID-19?

    • Jon Duvick Aug 6, 2020

      Best evidence to date (as discussed in previous TWiV episodes) suggests:
      1) SARS-CoV-2 spreads aerially in exhaled droplets, not as naked viral particles
      2) There is a minimum infectious dose for disease

      So anything that reduces infectious dose (like physical distance, face coverings) can reduce probability of disease spread.

      As a side note, some manufactured masks use electrostatic charge to trap droplets that would normally get through the fabric. So pore size is not the whole story.

      As part of your due diligence research, you might apply the search terms “pubmed: covid-19 mask” to view recent publications and preprints.

  18. Michael Irvine Aug 3, 2020

    Dogs being trained to sniff out people infected with SarsCovid19

  19. ken parkyn Aug 3, 2020

    Would you or research team have time to address the findings in the paper titled:
    “Targets of T Cell Responses to SARS-Cov-2 Coronavirus in Humans with COVID-19 Disease and Unexposed Individuals” published in Cell Press June 25 2020.
    Would the public benefit from a TWIV discussion on this report?

  20. Dan Von Pache Aug 4, 2020

    I luv the platform and I’m not anti thin-tank but, would LOVE to hear your recomendations had ALL of you lost your jobs and/or your employer had closed 4 moths ago or will permanently, as a direct result of YOU not being able to work full time because your kid(s) can’t return to school full time.

    FYI, most day-cares and summer camps have been opened (or never closed) while implementing some PEP measures to various degree. That’s not scientifically insignificant.

    On behalf of the countless and silenced vast millions of us, send us your salaries, and then talk.

  21. Hi, Can I ask if people with g6pd have higher risk of severe illness in covid-19?

  22. Al Dunbar Aug 8, 2020

    Where’s the table Vincent refers to? Would be handy to have.