TWiV 658: Everyone needs a H.E.A.R.T.

August 30, 2020

Daniel Griffin provides a clinical report on COVID-19, then we discuss CDC softening testing guidelines, Moderna vaccine phase I results in older people, Abbott’s $5 rapid antigen test, and reinfection with a distinct SARS-CoV-2 isolate, followed by listener email.

Hosts: Vincent Racaniello, Alan Dove, Dickson Despommier, and Rich Condit

Guest: Daniel Griffin

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Intro music is by Ronald Jenkees

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11 comments on “TWiV 658: Everyone needs a H.E.A.R.T.

  1. Dennis Mathias Aug 30, 2020

    Watched 658 and thought I’d send a picture of what we’re up against in Lincoln know, the midwest that’s getting away from us. But don’t know how to send the pic.

  2. Karen Aug 31, 2020

    Thank you all.
    Just a reminder in TWiV607 with Jeff Shaman, the Shaman & Galanti human Coronavirus study (tracking 4 common cold Coronaviruses in a sample population/ households) found the following:
    “We also found no significant association between repeat infections and symptom severity but strong association between symptom severity and belonging to the same family.”

    So maybe it’s too early to know the long term affects of re-infection & disease severity with SARS-CoV-2 if it became endemic, eg if re-infection occurs at different timelines, if SARS-CoV-2 if different genomes & ages of host (people), & so on…

  3. Karen Aug 31, 2020

    That was interesting Vincent about the Hong Kong man’s second infection, IgG antibodies not indicated day 1 of hospitalisation, but positive day 5, possibly due to a quicker memory immune response.
    My question, could the qPCR Ct values give an idea how long ago his infection occurred, therefore indicate more clearly if a memory immune response?
    Day 1 Ct 26.69, Day 5 Ct 32 (approx.)

    Considering he was asymptomatic, the infection may have occurred further back in time in Spain? Although that might depend on what SARS-CoV-2 variants were circulating in Spain at the time, as his return flight went to UK first, & the genome sequencing indicated close relationship with a Swiss variant, further back to English clade.

    • Karen Aug 31, 2020

      It also reminds me of the SARS-CoV-2 outbreak on a trawler, where 3 had been tested positive for IgG antibodies before the trip, and this was given as an example of antibody protection of re-infection. But what I thought was peculiar is their IgG antibody levels had dropped some when retested, after the outbreak. If they had been exposed /challenged to SARS-CoV-2 this second time, wouldn’t there have been an immune response, eg a boost to antibody levels?

  4. Jeffery Biss Aug 31, 2020

    Don’t worry about discussing th epolitics of COVID-19, Trump made it political. If supporters listen to this and are angered by that, so what. They are THE problem in this country.

  5. Lani Teshima Aug 31, 2020

    Hey TWiVers! When you get a web page in a different language, use Google Translate!

    Here’s that Korean language page, translated in Google translate (

    To summarize, a Starbucks had an outbreak that resulted in 56 positive cases, but none of the employees were infected at the time. The article went on to say the reason the employees didn’t get infected was because they wore masks and gloves.

  6. Keith Robinson Sep 1, 2020

    Hi TWiV.
    Good news from the north! After weeks of dead air and glacial inertia on the part of our government, Health Canada has today announced a “change in course on COVID-19 testing at home” (CBC News, Sept. 1st, It seems as though much letter writing is starting to pay off and that we may be moving toward at-home rapid testing.
    Okay, that’s one or two countries down and a couple hundred to go! If it wasn’t for TWiV and Michael Mina, I don’t think this could ever have happened, so thanks for persistently making us aware of the importance of Home Every day Antigen Rapid Testing (H.E.A.R.T.)

  7. Jay S Sep 2, 2020

    I don’t think that it makes sense to talk about “herd immunity” in the context of disease immunity alone. Herd immunity is specifically the mechanism where prevalence of immunity offers protection to vulnerable individuals by reducing the likelihood and severity of outbreaks, and that mechanism relies on infection immunity.

    Like you pointed out it doesn’t protect those who refuse to vaccinate, and even more worryingly, it doesn’t protect people who CAN’T vaccinate (like people who are immunocompromised). Even though disease protection from a vaccine is better than no vaccine, failing to deliver relatively long-lasting infection immunity (or mandatory boosters for short-lived immunity) would be very bad for those folks.

  8. David Lawrance Sep 2, 2020

    Though I can reluctantly agree with Dr. Griffin that the revised CDC testing guideline is defendable, it takes an especially lawyerly reading of it to be able to do so, only by paying attention to the “fine print.” But, let’s look at the big print. Regarding close exposure, first bullet: “You do not necessarily need a test…” So, let’s go on to the second bullet, “You should monitor yourself for symptoms.” Finally, if I’m not interacting with a vulnerable individual, I can simply ignore the third bullet. Thus, given that I’m a healthy guy who just had a close exposure, I’ll monitor symptoms and go about everything as usual. That’s not right!

    Missing is the quarantine recommendation. The guideline exists, mistakenly placed under a sidebar “If You Are Sick.” (Quarantine is of course indicated for those who have been exposed but who are NOT sick, but the guideline itself is okay) “Stay at home and monitor your health.” Bulleted under that: ” Stay home for 14 days after your last contact with a person who has COVID-19.”

    The quarantine guideline, already deeply buried within CDC’s Covid-19 pages, I suspect will soon be exhumed and cremated. It could have been included in the testing guideline, as it is certainly just as important as monitoring for symptoms, given that perhaps half of people with Covid-19 never develop any significant symptoms. The quarantine recommendation is also omitted in the CDC’s FAQ” “What should I do if I have had close contact with someone who has had COVID-19?” Two bullets answer that question: be alert for symptoms, take your temperature and follow CDC guidance if you have symptoms.

    Colorado, a strongly purple state, has a pretty clear testing guideline, simply stated, located at It is consistent with the CDC guideline, but it also explains. There is no fine print. This is what I also expect from CDC. I have my own feelings about why CDC is saying things the way that it is, and I hope that the thinking gets a good post-mortem before too long.