I just heard a Canadian physician say our problem here is vaccine hesitancy, not refusal. That gives me hope that many people can still read or hear something that will prompt them to be vaccinated, hopefully soon.
In my thread about the Alberta premier asking people to get vaccinated “for the love of God”, there were some excellent replies about the larger issues of viruses, diseases, variants and vaccines. I’ve taken those posts and put them here in a separate thread as they’re instructive far over and above the one Alberta issue I focused on.
As Lot’s Wife commented in that thread, “It would be nice to get the input, additions or clarifications, from those among us who are real experts in the field.”
summer started off the wider discussion I’m focusing on here, writing the following:
“I looked up the timeline for the Sabin oral polio vaccine, which was licensed in the U.S. in 1963 (like Covid, polio is also a virus.) From the time that it was licensed, it took more than 30 years to eradicate polio in the Americas, nearly 40 in Europe, and more than 50 years to get polio nearly eradicated worldwide.
“I am starting to think that the eradication of Covid may be a long haul as well.”
Lot’s Wife answered:
“The percentage of a population that must be vaccinated to gain herd immunity depends on the speed with which the disease spreads. That speed is measured by R(o), which is the number of unsuspecting people whom any one individual will infect. With the original COVID, the R(o) was around 2.5 and implied a required vaccination rate of something like 60-80%.
“Some of the subsequent variants have much higher R(o)s. Delta's, for instance, is somewhere between 5 and 8. If that is correct, herd immunity will require something closer to 100% vaccination. I don't think that is possible in today's world, so herd immunity may no longer be in the cards.”
Lot’s Wife again:
“There's a second scenario besides eventual conquest.
“Polio is a conservative virus; it is relatively stable over time, which is why there hasn't been a need for radically new vaccines since the 1950s and 1960s. Such a virus is relatively easy to vanquish.
“There are other viruses, however, that are unstable and mutate so fast that they cannot be conquered. Influenza is one of those. Every year (well, twice a year) scientists must design new vaccines to catch up with the virus's mutations. Some years the scientists guess right and the vaccines work well, sometimes they are not as effective and people only get partial protection. So people have no choice but to live with annual shots and frequent bouts of the illness.
“COVID looks more like influenza than polio, as evidenced by the rapid emergence of new variants and the diminution in the efficacy of existing vaccines. I don't think the odds are high of eradicating COVID given the speed of its mutations and its prevalence in parts of the world that are both densely populated and medically backward. So my hunch is that it's too late to eradicate the disease.
“If that's right, then we'll eventually fall into a pattern of periodic vaccinations that are more or less potent against the latest COVID strain/s. It will be like a very dangerous version of the flu. That's the price of having failed to nip it in the bud either in Wuhan, before China let millions of people travel for the New Year, or soon after its spread to other parts of the world.”
“The one hope is that it's thought that the Spanish flu eventually mutated into a milder strain. However given the "cleverness" of the Covid virus in mutating into more virulent strains, that scenario doesn't seem likely anytime soon.”
“The ideal situation would be the emergence of a variant that is far more communicable than the other strains and yet whose symptoms are mild. That would vitiate COVID and save us all this trouble. But if the milder strain were less communicable than more virulent variants, it would die out.”
Brother of Jerry:
“A couple of points:
“The formula for % required for herd immunity is pretty simple (as formulas go :)
“Herd immunity threshold = 1 - 1/R0
“So if R0 is 5, herd immunity is 1 - 1/5 = .8 = 80%
“If R0 is 8, herd immunity starts at 1 - ⅛ = .875 = 87.5%
“Measles has a ferocious R0 of about 18 if I recall correctly, so herd immunity is 94.4%. Damn near everyone needs to be vaccinated to stop measles.
“The hard part of figuring herd immunity is coming up with the correct value for R0 in the first place. Plus, R0 can change over time, as it has with Covid. Delta variant has a higher R0.
“As for eradicating covid, I'm pretty sure that is not possible. Polio and smallpox were viruses that were so specialized to humans that they could not naturally infect any other animals. Therefore, if you can eradicate the virus in humans, job done - it's eradicated.
“I think various other animals can be infected with covid. A variant may eventually arise that is both more contagious than other variants, pushing them out of the human population, and can only be caught by humans. Then it can be eradicated. In the meantime, we get to pass it back and forth between ourselves and other animals, which is part of why influenza is still around.”
“On R(o) and herd immunity, the more conservative experts want to build in a cushion in case the estimates are too low. The figures I presented, including the "nearly 100%" prediction, are from Osterholm, who's obviously worried that the R(o) calculations may be too optimistic. An ounce of prevention. . .
“Second, I am not aware of any evidence that the COVID variants emerged from animals. It appears at first glance that the virus is surprisingly unstable within human populations. It may be that the influenza-type interaction between birds, pigs, and humans is not necessary for COVID to mutate lightning fast.
“I like your reference to measles, a disease whose R(o) is too high for eradication to be practically possible. Given the problems inherent in such a large global human population, an R(o) of 10 might be too much insofar as it's impossible to get 90% of humans vaccinated. Polio, after all, is still with us. That's the worst-case scenario for COVID, and we are getting closer to it all the time.”
>Polio, after all, is still with us.
“The CDC says that of the three variants of Polio, two have been eradicated. "The last evidence of wild poliovirus type 1 transmission in Nigeria was in September 2018, leaving only two polio-endemic countries (having never interrupted the transmission of indigenous wild poliovirus type 1), which are Afghanistan and Pakistan."https://www.cdc.gov/polio/progress/index.htm
“This website was linked by the CDC. It lists 39 known cases worldwide of Polio as of Sept. 2, 2021.https://polioeradication.org/polio-today/polio-now/this-week/
“Pakistan and Afghanistan are great examples of countries in which their own governments' writs do not run. There's little chance of getting control of the virus while there is so much instability there.
“Measles is still with us, too, of course. BoJ puts the R(o) there at 18, which is the high range of the estimates (12-18). But if we take his number, a vaccination rate of 94% would produce herd immunity. If you take the lower calculation of 12, the required rate would be 92%. Empirically, I don't think either is achievable.
“Your suggestion of a uniquely communicable but symptomatically mild variant is, I suspect, the most promising, albeit remote, possibility.”
“For the sake of argument, I also looked up measles, which dates back to the 10th century. At the turn of the 20th century, measles killed about 6,000 people in the U.S. per year, Per the CDC, the first effective, licensed vaccine was available in 1963. Measles was considered eliminated from the U.S. in 2000 through widespread vaccination efforts, although there have been a couple of outbreaks since.https://www.cdc.gov/measles/about/history.html
“A CDC linked website:https://www.historyofvaccines.org/timeline/all?timeline_categories%5B%5D=51
“ETA: You might very well be correct that a high vaccination rate for Covid might very well be unachievable in the current political climate. I'm starting to wonder if a more hard line approach might be required, i.e. employers requiring the vaccine for employment.”
That was the end of the discussion I wanted to highlight from my previous thread.
At the end (in response to a secondary issue for my purposes here) Lot’s Wife made a comment that summarizes the crucial points by saying:
“With a little luck you can knock off an emerging disease if you hit it early and hard but the odds of success go down the longer you wait. We waited a long time with COVID.”
Yes indeed, a long time.
On another note, I’ve been wanting to say a big thank you to CZ who has given us space and leeway to discuss all the many and varied facets of the COVID-19 pandemic.
It may at first seem to be off-topic from Mormonism, the subject of this forum. But it isn’t because it involves research, reason, logic, rational debate and deep thought (the latter in particular to wrench a person’s affiliation from an idea or a group to which they may be illogically or mistakenly or unthinkingly wedded. Besides, as I’ve often said, to me the most intriguing facet of Mormonism is that absolutely every topic on earth seems to apply to it in one way or another. It keeps the subject interesting indeed. Certainly much more so than any SM I ever attended, not all that many in number, comparative to the bulk of RfM posters certainly, but as many as I could stand before I just walked away. I was lucky, nobody ever called me to come back. Good riddance, I can imagine them saying. Because. Questions. They don't like questions.