12 votes

SARS-CoV-2-specific T cell immunity in cases of COVID-19 and SARS, and uninfected controls (PDF)

3 comments

  1. Amarok
    (edited )
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    Finally, some good news, peer-reviewed, accepted, and published as a pre-print in Nature. The short version, in English... People who had SARS are immune/resistant to Covid-19 even though it's...

    Finally, some good news, peer-reviewed, accepted, and published as a pre-print in Nature. The short version, in English...

    People who had SARS are immune/resistant to Covid-19 even though it's been 17 years.

    People who have had betacoronavirus (most strains except MERS generally harmless in humans, transmitted by dogs, cows, bats, rodents, camels) have immunity through another separate vector. This is the likely source for people who present with 'natural' immunity and are asymptomatic carriers after infection by Covid-19.

    This also lends tremendous weight to the argument that immunity from Covid-19 is long lasting, likely decades. That means herd immunity is very real, though we probably don't want to infect the 70%+ of the population necessary to get there - vaccines are clearly better.

    This also means we have two vectors/methods to use for vaccines, and only one has been explored at present. It also means we can probably kick this virus' ass back into oblivion unless it learns how to mutate rapidly (previous research indicates it has slower than usual mutations).

    It also implies that had we followed through with developing a SARS vaccine, or a MERS vaccine, both of those would have likely been effective at stopping Covid-19 as well, and might have been able to stop this pandemic in its tracks. Let's hope we learn that lesson this time.

    Just to be very clear - this immunity doesn't mean you can't get sick. It simply means that if you do, it'll be much, much more mild, possibly even asymptomatic. This helps explain why the virus has so much variability in how it affects people when combined with other comorbidities and vitamin deficiencies.

    If you'd like, there is a more in-depth explanation from Dr. John Campbell breaking down the paper's implications.

    13 votes
  2. [2]
    wycy
    Link
    My non-biology-professional understanding is that these results were expected but not quite enough to be excited about yet, as the same results were achieved for the SARS vaccine research. All...

    My non-biology-professional understanding is that these results were expected but not quite enough to be excited about yet, as the same results were achieved for the SARS vaccine research. All vaccine candidates resulted in T cell immunity. However, all candidates also resulted in some form of Th2 immunopathology (immune enhancement syndrome), where subsequent exposure to the actual virus results in harsh symptoms (potentially but not necessarily worse than non-immunized) due to immune enhancement.

    It sounds like in the end they devised a clever way to avoid Th2 enhancement but never got to fully complete the work.

    Good to see that the vaccine produces the expected antibodies. Now we need to make sure those antibodies don't actually backfire and make the disease worse if/when you actually catch it. Based on the SARS research, that should end up being the case.

    6 votes
    1. Amarok
      (edited )
      Link Parent
      I've been trying to hunt down more info on MERS vaccine research and there's little out there. I'm interested in any progress we've made towards the second potential method of immunity, and...

      I've been trying to hunt down more info on MERS vaccine research and there's little out there. I'm interested in any progress we've made towards the second potential method of immunity, and curious if any of the vaccines in development have focused on this other weakness.

      Confirmation of long-lasting immunity and the potential for true herd immunity is definitely something to get excited about. That means any vaccines that succeed will put this virus on the run and get us out from under the lockdowns. It's the difference between our 'new normal' and going back to the old normal.

      Edit: Looks like there was exactly one MERS vaccine that reached clinical trials and was successful. The US Army was very interested due to their middle east troop deployments. I found one reference to CEPI continuing this work for Covid-19 in partnership with Moderna. I wonder if this is how the Moderna vaccine we're hearing hyped up lately operates.

      5 votes