TWiV 650: Virology is infinite

August 6, 2020

In this mid-week episode of Earth’s Virology Podcast, we analyze SARS-CoV-2 transmission among youths at a summer camp, adaptation to mice by passage, the importance of T cells for recovery from COVID-19, and listener questions.

Hosts: Vincent Racaniello, Rich Condit, Kathy Spindler, and Brianne Barker

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Download TWiV 650 (73 MB .mp3, 122 min)
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Weekly Science Picks 1:58:38

KathyBBC Witness History, Maurice Hilleman 9 minute audio (quotes by Paul Offit) “The fastest vaccine ever developed”And APOD Picture Rocks Sun Dagger

Intro music is by Ronald Jenkees

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12 comments on “TWiV 650: Virology is infinite

  1. Jon Duvick Aug 6, 2020

    Hi Vincent great show as always..,FYI the ‘Illinois’ rapid saliva hyperlink is incorrect- it links instead to the Columbia rapid test preprint. Thanks, Jon

  2. David Smith Aug 6, 2020

    Thanks for continuing the flood of anti-anti-think.
    Regarding the repeated suggestions that tests requiring a machine might not be appropriate for daily home use, but universities and large institutions could employ them – I keep running into the same problem with my back-of-the-envelope math. If a test takes as little as 15-20 minutes using a machine, just 300 students showing up would occupy that machine for 3 or 4 days running 24 hours a day to get all the results back – that’s PCR turnaround performance. Yes, a machine gives rapid test capability, but how many machines would a university need to make them actually useful in a real world application? Is that really practical?

    • profvrr Aug 7, 2020

      There is no questions that universities with lab capability should use the simpler machines. They will need lab approval but this should be done. Those universities who are not ramping up testing themselves are doing society a disfavor.

      • David Smith Aug 8, 2020

        Universities with lab capabilities can’t violate the laws of space and time. Unless there are simple machines that process hundreds of samples at once, you would need hundreds of machines to do daily rapid testing. It’s not a question of approval, it’s a question of simple math.

        • Jennifer H Aug 8, 2020

          96-well sample plates are standard in every lab with a thermocycler, thermocyclers often come with a second, 384-well heat block (to swap out for higher throughput) and university core labs often have multiple high throughput machines. Most of the time in a university research lab you are running just a few samples, maybe one run a day. One thermocycler can do 4 runs in an 8 hour shift, (384 x 4 = <1500 samples/day), plus positive and negative controls). Not every lab has the manpower or leadership to make it happen but they already have the machines to ramp up.

  3. Heidi Smith, MD Aug 7, 2020

    Dear Amazing TWIV team,

    Episode 640 with Michael Mina really got me fired up to write a letter to everyone I could think of urging immediate FDA approval, manufacturing and distribution of an inexpensive, rapid, home SARSCoV-2 test. In my attempts to find appropriate individuals and institutions to send it to I came across an article in the NYT about an at home surveillance test supported by the Gates Foundation that I thought would be interesting to you all and your listeners:
    The study had obtained authorization from Washington State health officials but was halted by the FDA in May 2020. The group conducting the study, SCAN, the Seattle Coronavirus Assessment Network, was working with the Gates Foundation, The Fred Hutchinson Cancer Research Center and the CDC.
    Oh, and can someone tell me how to submit my letter to the Letter Drafts page?

    You’re the best!

    • Jennifer H Aug 8, 2020

      It looks as though the Seattle test is a home-collected swab, but they still have to send it out to the lab. Same bottleneck of waiting while isolated and possibly missing work or school (or worse, not isolated and potentially spreading) until results get back. Mina’s home surveillance test would give the user results within minutes.

  4. Michelle Aug 7, 2020

    Three questions for Daniel: (1) How could Arizona halt its covid-19 cases within just weeks using no major policy changes? (2) What are the legal ramifications of mis-reporting covid-19 cases counts? (3) What are the legal ramifications of mis-reporting covid-19 death counts?

  5. Allan Frederick Moore Aug 8, 2020
    • Jennifer H Aug 8, 2020

      TWiV 599: Coronavirus update – we need a plan

      The interview with Doris Kully in this episode is focused on evaluating the plausibility of Ivermectin as a human anti-viral therapy.

  6. Vincent – Uh oh

    I believe you got the “signs v symptoms” definitions reversed [1:43.30].

    “A sign is something that can be observed externally, while a symptom is felt internally.”