Mix and match probably has more effect with different kinds of vaccines that cause the immune system to respond differently (i.e. J&J booster after Pfizer or Moderna, or Pfizer or Moderna booster after J&J). The Pfizer and Moderna vaccines are mostly similar, except for the larger dose of mRNA in each Moderna dose or half-dose (which is the likely reason for its increased effectiveness and durability after the first two shots). The J&J vaccine’s lower effectiveness may be due to being only one shot initially.
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I agree. I believe Moderna’s booster was 50mcg whereas the Pfizer booster was the same 30mcg as the original two shots.
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I did the PX2 then the M but it was not the booster it was the full M.
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And today the woman developer of Corbevax was interviewed on NPR. Has been nominated for a Nobel Peace Prize.
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That page says “A diverse portfolio of vaccines that utilizes a number of different biotechnologies is of critical importance.” Meanwhile, it appears that the US has gone all-in on mRNA vaccines from Pfizer and Moderna, resulting in lack of vaccine diversity in the US (because hardly anyone seems to want the J&J vaccine any more, and it may be a while before any other vaccine shows up in the US).
Glad to see someone else reading LYE! She’s wonderful.
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Regarding lack of vaccine diversity in the US, the US has 3 emergency or fully approved vaccines from 2 (of 5) vaccine technologies. Only 2 of the vaccines, both using the same vaccine technology, seem to be desired in the US. This is small compared to many other countries: Vaccination Rates, Approvals & Trials by Country – COVID19 Vaccine Tracker .
Is vaccine diversity really required or helpful? Isn’t efficacy more important?
Given all the diversity in vaccines across the world I wonder if there are significant differences in number of cases, hospitalizations and deaths etc….between various countries after taking into account demographics, comorbidies and such?
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It matters for those with allergies to vaccine ingredients. Those with allergy to polyethylene glycol may have trouble with two of the three vaccines in the US, and the third uses a related compound polysorbate 80.
It also matters in that efficacy can vary depending on the situation. For example, the Pfizer vaccine appears to wane relatively quickly and lose efficacy against variants, so having other vaccines that may be more durable could be desirable in the face of uncertain virus waves.
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many of those who are hesitent might be more willing to take a vaccine such as Novavax. Suprised it has not been approved for use in the US yet
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Pfizer vaccine booster study in Israel:
https://www.nejm.org/doi/full/10.1056/NEJMoa2115624
After initial two dose vaccination, booster appears to have made death from COVID-19 10 times less likely than no booster.
Note that almost all vaccination in Israel was done with the Pfizer vaccine, and the immunity from the Pfizer vaccine appears to fall faster and greater than some other vaccines.
Another reason for vaccine diversity: some people may have significant undesirable effects (not just allergies) from a particular vaccine or class of vaccines, so a different vaccine of a different class of vaccines may be more usable by such people.
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Looks like Pfizer and BioNTech are doing a trial of an Omicron-targeted vaccine. Participants must have one of the following vaccine statuses:
- 2 doses of Pfizer - BioNTech vaccine – will get 1 or 2 doses of the Omicron-targeted vaccine.
- 3 doses of Pfizer - BioNTech vaccine – will get 1 dose of Omicron-targeted vaccine or 4th dose of original vaccine.
- Unvaccinated with any COVID-19 vaccine – will get 3 doses of the Omicron-targeted vaccine.
Looks like people who got any other COVID-19 vaccine are not eligible for this trial.
If one were lucky enough to get a slot, they had a much better chance. I feel for those who weren’t:
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I’d like someone, anyone, to identify the actual animal reservoir for the COVID virus. To my knowledge that’s never happened after 2+ years of searching for that elusive critter. The fact that China never allowed (and continues to refuse) any outside investigation into the origin is a huge red mark against any wet market origin theories (and those wet markets remain open for business so clearly China isn’t concerned about the dangers those markets possess to unleash another pandemic virus). Lastly, this article seems premature since the studies haven’t been peer reviewed yet.
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CDC estimates of seroprevalence of antibodies from COVID-19 infection (not vaccination) to be 140 million in the US, or 43.3% of the population (as of now, could change as time goes on). This was recently widely reported in various media.
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Wow
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This should get more people vaccinated!
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