6 ms·

CDC: Covid vaccine effectiveness fell from 91% to 66% with Delta variant

18 points by AndrewBissell 5y ago

DamnYuppie 5y ago
Does anyone know how the 66% effectiveness of the vacine compares to people who were exposed to COVID but never got the vaccine?
- smt88 5y ago
  It doesn't matter in countries like the US where the vaccine is free to anyone who wants it. We know the vaccine improves survival regardless of previous infections. https://www.uchicagomedicine.org/forefront/coronavirus-disease-covid-19/do-i-need-a-vaccine-if-i-had-covid https://www.uchicagomedicine.org/forefront/coronavirus-disea... It's a little bit like mixing and matching vaccines to get better protection (which some countries are forced to do because they don't have access to the best single vaccine).
  - AndrewBissell 5y ago
    Nothing in your link supports the claim "we know the vaccine improves survival regardless of previous infections." > It doesn't matter in countries like the US where the vaccine is free to anyone who wants it How about the medical bills for a life-altering adverse event? Are those free for anyone who has to pay them? These considerations matter when we're talking about administering a vaccine which may provide very slim or no additional protection over natural immunity. There has already been one study suggesting the second dose of Pfizer even reduces cellular and humoral immune response.
    - zht 5y ago
      oh sorry how many of those life altering adverse events have there been as a percentage of people vaccinated?
      - AndrewBissell 5y ago
        How many extremely bad disease outcomes have there been as a percentage of all Covid reinfections?
    - bananabiscuit 5y ago
      There’s a CDC study that shows vaccinating while previously infected, further boosts your immunity by more than double https://www.cdc.gov/media/releases/2021/s0806-vaccination-protection.html https://www.cdc.gov/media/releases/2021/s0806-vaccination-pr... What they don’t mention is that previous infection alone is at least as good as vaccination alone. According to data from Israel, previous infection is about 6x more effective in fact. https://www.cdc.gov/media/releases/2021/s0806-vaccination-protection.html https://www.cdc.gov/media/releases/2021/s0806-vaccination-pr... Given that, I don’t at all agree with the conclusion of that CDC study that you HAVE to get vaccinated if you had a previous infection.
      - AndrewBissell 5y ago
        What that study shows is that unvaccinated people in the study cohort were twice as likely to experience a reinfection. A lot of things could explain that and it's a far cry from establishing that it boosts immunity. The study period was also during the point when effectiveness of the initial mRNA vaccine doses was probably peaking.
    - triceratops 5y ago
      > How about the medical bills for a life-altering adverse event? Like when you get seriously ill with Covid and have to be hospitalized in the ICU? That's more likely than an adverse reaction to a vaccine, if we're assuming that everyone will get Covid at some point.
      - AndrewBissell 5y ago
        We're specifically discussing people with immunity from having recovered from a prior Covid infection, in whom serious life-altering illness from a reinfection is also extraordinarily rare.
        triceratops 5y ago
        > in whom serious life-altering illness from a reinfection is also extraordinarily rare. Only as far as we're talking about reinfections from currently known variants. We've seen that current vaccines are still pretty good against Delta despite not being tailored to it. Is it not possible for vaccines to provide immunity against a future variant that's much deadlier upon reinfection?
    - zeku 5y ago
      Link the study or delete your comment.
      - AndrewBissell 5y ago
        Here you go. Wonder what a third dose will do! https://www.biorxiv.org/content/10.1101/2021.03.22.436441v1 https://www.biorxiv.org/content/10.1101/2021.03.22.436441v1
- criticaltinker 5y ago
  Immunity acquired through natural infection confers protection that is at least as effective as vaccination [1]. However, the delta variant and other VOCs have mutations that will reduce this protection in both vaccinated and naturally immune individuals. > A previous history of SARS-CoV-2 infection was associated with an 84% lower risk of infection, with median protective effect observed 7 months following primary infection. This time period is the minimum probable effect because seroconversions were not included. This study shows that previous infection with SARS-CoV-2 induces effective immunity to future infections in most individuals. [1] [1] SARS-CoV-2 infection rates of antibody-positive compared with antibody-negative health-care workers in England: a large, multicentre, prospective cohort study (SIREN) https://pubmed.ncbi.nlm.nih.gov/33844963/ https://pubmed.ncbi.nlm.nih.gov/33844963/
- hattmall 5y ago
  Reinfection rate is less than 1%. The biggest issue is that there were lots of false positives with certain tests if you had Flu or other coronavirus colds even if asymptomatic. Even current antibody testing can't distinguish COVID-19 from other coronavirus based colds. If you had asymptomatic or low symptoms and positive test there's a fair chance you didn't really have COVID. If you had symptoms with shortness of breath and loss of smell without heavy congestion you probably did have COVID.
angelzen 5y ago
I do not understand what the 5 year plan is. Even less what the 50 year plan is. On one hand: We are blessed to have access to mass genetic vector vaccines. Genetic vector vaccines are amazing at shaving off the sharp edge of the pandemic. Even after effectiveness drops against infection, they are still amazing at preventing severe infections. "VE for severe disease is *still high* after 6 months - 94% for ages 40-59, 86% for 60+.", https://twitter.com/_lewisy/status/1430291421085552641 https://twitter.com/_lewisy/status/1430291421085552641. On the other hand: * There is no path to ZeroCovid due to high airborne infectiousness, leaky genetic vector vaccines, immense human global population and reported animal reservoirs. * The genetic vector vaccine effectiveness appears to diminish after ~6 months, thus booster shots. * Leaky genetic vector vaccines are bound to give raise to vaccine-resistant variants, just like incomplete antibiotic courses give raise to antibiotic-resistant bacteria. * Every time a new genetic vector vaccine variant is developed, it takes a long time to pass the FDA tests and even then it carries a tiny, but not zero, risk of ADE. OK, we'll roll the Russian Roulette once. But we can't forever play Russian Roulette with a mutating virus.
- websites2023 5y ago
  Everyone’s going to get COVID eventually. Natural immunity + 3 rounds of the vaccine are probably enough to make it acceptable level of deadly. “Zero COVID” was never possible.
  - Falandafa2021 5y ago
    Only for New Zealand who locked down an entire country over one case
    - hattmall 5y ago
      Unless they lockdown forever it's literally not going to matter. Additionally the longer they delay the acquisition of natural immunity the worse it will eventually be. The best course of action in the begining would have been to encourage only the vulnerable to isolate. Natural immunity is much better than the vaccines. COVID currently is worse for vaccinated people than it was for unvaccinated a year ago. The rate of severe infection with Delta among vaccinated is higher than the rate of severe infection of the general population a year ago with Original COVID. Natural immunity has less than 1% reinfection rate vs a nearly 40% infection rate for fully vaccinated. We talk about how all the current deaths of unvaccinated people could be prevented with vaccines, but skip that they could have also been prevented in 99% of cases by them simply catching COVID last year. Im all for vaccines and vaccine + COVID infection is currently the best protection, but that is an actually riskier proposition than simply having caught COVID in the begining for normal healthy people.
maurosilber 5y ago
Will journalist ever report confidence intervals? The report says: > Adjusted VE during this Delta predominant period was 66% (95% CI = 26%–84%) compared with 91% (95% CI = 81%–96%) during the months preceding Delta predominance So it's not much accurate the 66%, it could be anywhere between 26% to 84%.
SnowProblem 5y ago
In the FDA's press release yesterday [1], they justified Pfizer approval by saying the vaccine had a 91% effectiveness. But everyone knows that number is no longer true - the data was from March, before Delta. If the FDA were acting responsibly and credibly, they would have used the latest data, but then approval doesn't look so favorable. It's probably relevant that Pfizer spent over $200M lobbying politicians over the past 20 years, more than any other pharmaceutical [3]. And Biden's administration clearly weren't happy with the FDA - just last week they said they are looking for a new head for November [3]. Interesting how approval came the next week. How much money does Pfizer stand to gain, once mandates and boosters? $15/shot? [1] https://www.fda.gov/news-events/press-announcements/fda-approves-first-covid-19-vaccine https://www.fda.gov/news-events/press-announcements/fda-appr... [2] https://jamanetwork.com/journals/jamainternalmedicine/fullarticle/2762509#ioi200006t1 https://jamanetwork.com/journals/jamainternalmedicine/fullar... [3] https://www.bloomberg.com/news/articles/2021-08-19/janet-woodcock-ruled-out-for-permanent-fda-commissioner-post https://www.bloomberg.com/news/articles/2021-08-19/janet-woo...
- nradov 5y ago
  Approval of a vaccine isn't contingent on a specific percentage effectiveness. Less effective drugs are approved all the time as long as the health benefits outweigh the risks and side effects.

18 points by AndrewBissell 5y ago

Does anyone know how the 66% effectiveness of the vacine compares to people who were exposed to COVID but never got the vaccine?

smt88 5y ago
It doesn't matter in countries like the US where the vaccine is free to anyone who wants it. We know the vaccine improves survival regardless of previous infections. https://www.uchicagomedicine.org/forefront/coronavirus-disease-covid-19/do-i-need-a-vaccine-if-i-had-covid https://www.uchicagomedicine.org/forefront/coronavirus-disea... It's a little bit like mixing and matching vaccines to get better protection (which some countries are forced to do because they don't have access to the best single vaccine).
- AndrewBissell 5y ago
  Nothing in your link supports the claim "we know the vaccine improves survival regardless of previous infections." > It doesn't matter in countries like the US where the vaccine is free to anyone who wants it How about the medical bills for a life-altering adverse event? Are those free for anyone who has to pay them? These considerations matter when we're talking about administering a vaccine which may provide very slim or no additional protection over natural immunity. There has already been one study suggesting the second dose of Pfizer even reduces cellular and humoral immune response.
  - zht 5y ago
    oh sorry how many of those life altering adverse events have there been as a percentage of people vaccinated?
    - AndrewBissell 5y ago
      How many extremely bad disease outcomes have there been as a percentage of all Covid reinfections?
  - bananabiscuit 5y ago
    There’s a CDC study that shows vaccinating while previously infected, further boosts your immunity by more than double https://www.cdc.gov/media/releases/2021/s0806-vaccination-protection.html https://www.cdc.gov/media/releases/2021/s0806-vaccination-pr... What they don’t mention is that previous infection alone is at least as good as vaccination alone. According to data from Israel, previous infection is about 6x more effective in fact. https://www.cdc.gov/media/releases/2021/s0806-vaccination-protection.html https://www.cdc.gov/media/releases/2021/s0806-vaccination-pr... Given that, I don’t at all agree with the conclusion of that CDC study that you HAVE to get vaccinated if you had a previous infection.
    - AndrewBissell 5y ago
      What that study shows is that unvaccinated people in the study cohort were twice as likely to experience a reinfection. A lot of things could explain that and it's a far cry from establishing that it boosts immunity. The study period was also during the point when effectiveness of the initial mRNA vaccine doses was probably peaking.
  - triceratops 5y ago
    > How about the medical bills for a life-altering adverse event? Like when you get seriously ill with Covid and have to be hospitalized in the ICU? That's more likely than an adverse reaction to a vaccine, if we're assuming that everyone will get Covid at some point.
    - AndrewBissell 5y ago
      We're specifically discussing people with immunity from having recovered from a prior Covid infection, in whom serious life-altering illness from a reinfection is also extraordinarily rare.
      - triceratops 5y ago
        > in whom serious life-altering illness from a reinfection is also extraordinarily rare. Only as far as we're talking about reinfections from currently known variants. We've seen that current vaccines are still pretty good against Delta despite not being tailored to it. Is it not possible for vaccines to provide immunity against a future variant that's much deadlier upon reinfection?
  - zeku 5y ago
    Link the study or delete your comment.
    - AndrewBissell 5y ago
      Here you go. Wonder what a third dose will do! https://www.biorxiv.org/content/10.1101/2021.03.22.436441v1 https://www.biorxiv.org/content/10.1101/2021.03.22.436441v1
criticaltinker 5y ago
Immunity acquired through natural infection confers protection that is at least as effective as vaccination [1]. However, the delta variant and other VOCs have mutations that will reduce this protection in both vaccinated and naturally immune individuals. > A previous history of SARS-CoV-2 infection was associated with an 84% lower risk of infection, with median protective effect observed 7 months following primary infection. This time period is the minimum probable effect because seroconversions were not included. This study shows that previous infection with SARS-CoV-2 induces effective immunity to future infections in most individuals. [1] [1] SARS-CoV-2 infection rates of antibody-positive compared with antibody-negative health-care workers in England: a large, multicentre, prospective cohort study (SIREN) https://pubmed.ncbi.nlm.nih.gov/33844963/ https://pubmed.ncbi.nlm.nih.gov/33844963/
hattmall 5y ago
Reinfection rate is less than 1%. The biggest issue is that there were lots of false positives with certain tests if you had Flu or other coronavirus colds even if asymptomatic. Even current antibody testing can't distinguish COVID-19 from other coronavirus based colds. If you had asymptomatic or low symptoms and positive test there's a fair chance you didn't really have COVID. If you had symptoms with shortness of breath and loss of smell without heavy congestion you probably did have COVID.

angelzen 5y ago

I do not understand what the 5 year plan is. Even less what the 50 year plan is. On one hand: We are blessed to have access to mass genetic vector vaccines. Genetic vector vaccines are amazing at shaving off the sharp edge of the pandemic. Even after effectiveness drops against infection, they are still amazing at preventing severe infections. "VE for severe disease is *still high* after 6 months - 94% for ages 40-59, 86% for 60+.", https://twitter.com/_lewisy/status/1430291421085552641 https://twitter.com/_lewisy/status/1430291421085552641. On the other hand: * There is no path to ZeroCovid due to high airborne infectiousness, leaky genetic vector vaccines, immense human global population and reported animal reservoirs. * The genetic vector vaccine effectiveness appears to diminish after ~6 months, thus booster shots. * Leaky genetic vector vaccines are bound to give raise to vaccine-resistant variants, just like incomplete antibiotic courses give raise to antibiotic-resistant bacteria. * Every time a new genetic vector vaccine variant is developed, it takes a long time to pass the FDA tests and even then it carries a tiny, but not zero, risk of ADE. OK, we'll roll the Russian Roulette once. But we can't forever play Russian Roulette with a mutating virus.

websites2023 5y ago
Everyone’s going to get COVID eventually. Natural immunity + 3 rounds of the vaccine are probably enough to make it acceptable level of deadly. “Zero COVID” was never possible.
- Falandafa2021 5y ago
  Only for New Zealand who locked down an entire country over one case
  - hattmall 5y ago
    Unless they lockdown forever it's literally not going to matter. Additionally the longer they delay the acquisition of natural immunity the worse it will eventually be. The best course of action in the begining would have been to encourage only the vulnerable to isolate. Natural immunity is much better than the vaccines. COVID currently is worse for vaccinated people than it was for unvaccinated a year ago. The rate of severe infection with Delta among vaccinated is higher than the rate of severe infection of the general population a year ago with Original COVID. Natural immunity has less than 1% reinfection rate vs a nearly 40% infection rate for fully vaccinated. We talk about how all the current deaths of unvaccinated people could be prevented with vaccines, but skip that they could have also been prevented in 99% of cases by them simply catching COVID last year. Im all for vaccines and vaccine + COVID infection is currently the best protection, but that is an actually riskier proposition than simply having caught COVID in the begining for normal healthy people.

maurosilber 5y ago

Will journalist ever report confidence intervals? The report says: > Adjusted VE during this Delta predominant period was 66% (95% CI = 26%–84%) compared with 91% (95% CI = 81%–96%) during the months preceding Delta predominance So it's not much accurate the 66%, it could be anywhere between 26% to 84%.

SnowProblem 5y ago

In the FDA's press release yesterday [1], they justified Pfizer approval by saying the vaccine had a 91% effectiveness. But everyone knows that number is no longer true - the data was from March, before Delta. If the FDA were acting responsibly and credibly, they would have used the latest data, but then approval doesn't look so favorable. It's probably relevant that Pfizer spent over $200M lobbying politicians over the past 20 years, more than any other pharmaceutical [3]. And Biden's administration clearly weren't happy with the FDA - just last week they said they are looking for a new head for November [3]. Interesting how approval came the next week. How much money does Pfizer stand to gain, once mandates and boosters? $15/shot? [1] https://www.fda.gov/news-events/press-announcements/fda-approves-first-covid-19-vaccine https://www.fda.gov/news-events/press-announcements/fda-appr... [2] https://jamanetwork.com/journals/jamainternalmedicine/fullarticle/2762509#ioi200006t1 https://jamanetwork.com/journals/jamainternalmedicine/fullar... [3] https://www.bloomberg.com/news/articles/2021-08-19/janet-woodcock-ruled-out-for-permanent-fda-commissioner-post https://www.bloomberg.com/news/articles/2021-08-19/janet-woo...

nradov 5y ago
Approval of a vaccine isn't contingent on a specific percentage effectiveness. Less effective drugs are approved all the time as long as the health benefits outweigh the risks and side effects.