Thursday, May 28, 2020

Herd Immunity? Not Anytime Soon.


A graphic in The New York Times reveals that the prospect of developing 'herd immunity' to the Covid-19 virus is not at all likely.

The top left shows the infection/antibodies density that could create herd immunity.  Contrast that with the density levels that now exist in New York, London, even Stockholm where there hasn't been much of a lockdown.



Herd immunity is commonly defined as "the resistance to the spread of a contagious disease within a population that results if a sufficiently high proportion of individuals are immune to the disease, especially through vaccination.

"the level of vaccination needed to achieve herd immunity varies by disease but ranges from 83 to 94 percent"


6 comments:

  1. As I long suspected. There is no herd immunity to the other coronaviruses that circulate as the common cold. Indeed, our immune response to the cold is so weak that we can catch it year after year. I'm afraid the best we can hope for is that SARS-COV2 mutates to a less virulent form. Until then, it's masks, distancing and hand washing.

    Cap

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  2. Hey, Cap. We can also hope for a new generation of antivirals to reduce the lethality and speed recoveries and, ultimately, a vaccine. Herd immunity just isn't realistic, not with these contagions. Measles, mumps - sure or at least before the anti-vaxxers took the field. Any thoughts on what needs to be done with those who may refuse a Covid-19 vaccine?

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  3. When an anti-vaxxer's kid get the measles, they often invite other anti-vaxxer kids to a "measles party," so they can get infected and become immune. Judging by the anti-vaxxer signs at the "freedumb rallies," the Covid-19 parties have already started.

    Cap

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  4. I've heard of these "plague parties" Cap. Foolish in the extreme. My daughter had a telephone consult with her rheumatologist today, a woman she last visited in her office in January.

    The rheumatologist said she wasn't seeing patients in her office. In January her husband, an ER doctor, picked up the Covid virus at his hospital. He came home and, before he showed any symptoms she and their two, under-10 kids contracted it.

    The kids bounced back fairly quickly. Her husband had a harder time but fully recovered. She sustained lung and heart damage and that earned her a stint in the ICU. Although the virus is seemingly gone this woman said her heart and lungs have lasting damage. She's now incapable of even moderate exertion, a problem when you have two young children.

    Her doctors intend to wait until their workload subsides to do further evaluation of her condition, the degree of her impairment and whether this will shorten her life.

    Then you have Jason Kenney dismissing it as a flu virus.

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  5. What I find most surprsing in these graphs, is that Stockholm where so called "lock down" measures were much more lax....that it appears to be the furthest from herd immunity as opposed to cities that had stricter measures put in place. Intuititively I would have thought that the broad based rate of infection would have been higher in Sweden than in other countries...but if I'm understanding these illustrations correctly, it actually looks like the least. I'm wondering if that might be due to the fact that Stockholm has the lowest population of the 6, and likely the lowest density I would assume.

    I was one who was definitely hoping that herd immunity would happen, but unfortunately its looking less and less likely....maybe in 18 months best case, but that's only if antibodies last that long....I'm reading some sources as saying it might only be 3 or 4 months.

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  6. Gordie, when you write that "some sources say" that's decidedly Trumpian. It's diatribe. "Some people think Joe Scarborough might have murdered his legislative assistant." That's conspiracy theory garbage.

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