5 ms·

Some interesting remarks to put in context before judging this MIT claim as true or false: - Racial bias in medical research is real and methods for increasing

Some interesting remarks to put in context before judging this MIT claim as true or false: - Racial bias in medical research is real and methods for increasing fairness are urgently needed in clinical trials - We don't know for sure how racial bias was balanced on most phase 3 trials, because most research protocols were not disclosed to the science community - Since efficacy was measured by the sub population in the phase 3 trials who got infected, we can perhaps have other confounding factors who can affect more, or less, some ethnicities (for example, someone can raise the hypothesis that some cultures are more prone to use masks and keep distancing, reducing inherent risks, and that can be true) - Sample sizes for the phase 3 studies so far very small (perhaps enough to assess minimal efficacy?) for ANY race/ethnicity. We hope that with the increase of the vaccinated population we can have a more precise estimate - We are talking about 95% inside a confidence interval which is still uncertain lower/higher boundaries, given the small sample - It is very dangerous to claim any statistical conclusion with small sample sizes - Almost all "advanced machine learning AI methods" fail miserably. And they fail even worse with small datasets (which is the case). Examples are the handful of "covid pollsters" we got since the beginning of 2020, trying to guess how many people would die, or get infected. - About vaccine efficacy in asians - we should monitor phase 3 results of CoronaVac (the chinese vaccine) trials (which are in course in China, Brazil and other countries), so we can account for these biases. I heard these results are coming in the next few weeks

klipt 6y ago
Also, the main purpose of a vaccine is herd immunity. If a large enough majority of the population become immune that we achieve herd immunity, that will still protect the minority of people for whom the vaccine didn't work.
- acqq 6y ago
  No, at the moment "the main purpose of a vaccine" is still not "herd immunity" at all. The Phase 3 trial protocols measured and presented the "efficacy" which is defined as the reducing the chance of the vaccinated getting sick -- that is, merely reducing the severity of disease among those who were vaccinated. https://www.medscape.com/viewarticle/941030?src=soc_tw_201118_mscpedt_news_mdscp_vaccine&faf=1 https://www.medscape.com/viewarticle/941030?src=soc_tw_20111... "In an ideal world, a vaccine would prevent infection entirely and, it follows, also prevent disease and severe disease. But this may be hard to achieve for a respiratory virus vaccine. Animal challenge data suggest that vaccinated animals may still be infected even if they don't experience symptoms. A vaccine that is able to reduce the severity of disease, even if it cannot prevent infection entirely, would obviously still have enormous public health value. Therefore, this is what trials target as their primary aim." Not all vaccines are the same. For mumps, totally different kind of disease, to prevent an outbreak, there was a following calculation: https://vector.childrenshospital.org/2017/03/social-media-mumps-herd-immunity/ https://vector.childrenshospital.org/2017/03/social-media-mu... "since one in 10 vaccinated people are still susceptible to mumps, an overall vaccination rate of 96 percent is needed to prevent an outbreak" For Covid-19, to note from the first source again: "A vaccine that is able to reduce the severity of disease, even if it cannot prevent infection entirely, would obviously still have enormous public health value. Therefore, this is what trials target as their primary aim."
  - gojomo 6y ago
    Yes and no. These vaccines have been formally tested for their ability to protect the recipient, & there is some unquantifiable risk that they'll still get harmless-to-themselves mild infections – especially nasal/mucosal/surface infections – that can still transmit to others. But it's reasonable to also expect the following to be shown when there's more time: * The milder infection makes such infections less transmissible (in terms of duration-of-infectiousness of quantity-of-sheddding) * such superficial infections in the vaccinated don't recur often, or as they recur become ever-milder – because the nasal/mucosal surfaces themselves eventually improve their immunity. So, an extra step is required to achieve the simplified idea of 'herd immunity', but the vaccines is still one step in that direction. So it is still very much the hope & eventual aim of these vaccines to keep enough people alive, with mild easily-recovered infections, that 'herd immunity' (and thus much-lower or almost non-existent rates of infection even in the unvaccinated) is reached.
    - acqq 6y ago
      > But it's reasonable to also expect ... - The milder infection makes such infections less transmissible (in terms of duration-of-infectiousness of quantity-of-sheddding) Neither reduced duration of infectiousness nor reduced quantity of shedding by definition protects the vulnerable. It can reduce the speed of spread, but that by definition doesn't even mean that a vaccinated person can visit their non-vaccinated or immune suppressed relative without the mask. For all we know the "quantity of shedding" has to be very low for transmission to provably not occur -- some experts estimate that a single droplet containing only 500 viruses is enough. To compare, the typical tests measure the presence of virus RNA starting with many millions in the sample and the tests do detect asymptomatic persons -- those who don't get sick now. > superficial infections in the vaccinated don't recur often From the studies of other coronaviruses it is known that infections do recur. And finally, we even know that even some percentage of people who get the vaccine become the disease later and are observably sick -- that's the difference to 100 to efficacy percentage (e.g. 5 of 100 who received the vaccine, or every 20th, if the efficacy is 95%). And we can also expect effectiveness (protection of the vaccine in the real world) to be lower than efficacy (reported from trials). In short, for all we know at the moment, the life will continue to be hard for those who don't get the vaccine and those whose immune system can't respond to the vaccine.

klipt 6y ago

Also, the main purpose of a vaccine is herd immunity. If a large enough majority of the population become immune that we achieve herd immunity, that will still protect the minority of people for whom the vaccine didn't work.

acqq 6y ago
No, at the moment "the main purpose of a vaccine" is still not "herd immunity" at all. The Phase 3 trial protocols measured and presented the "efficacy" which is defined as the reducing the chance of the vaccinated getting sick -- that is, merely reducing the severity of disease among those who were vaccinated. https://www.medscape.com/viewarticle/941030?src=soc_tw_201118_mscpedt_news_mdscp_vaccine&faf=1 https://www.medscape.com/viewarticle/941030?src=soc_tw_20111... "In an ideal world, a vaccine would prevent infection entirely and, it follows, also prevent disease and severe disease. But this may be hard to achieve for a respiratory virus vaccine. Animal challenge data suggest that vaccinated animals may still be infected even if they don't experience symptoms. A vaccine that is able to reduce the severity of disease, even if it cannot prevent infection entirely, would obviously still have enormous public health value. Therefore, this is what trials target as their primary aim." Not all vaccines are the same. For mumps, totally different kind of disease, to prevent an outbreak, there was a following calculation: https://vector.childrenshospital.org/2017/03/social-media-mumps-herd-immunity/ https://vector.childrenshospital.org/2017/03/social-media-mu... "since one in 10 vaccinated people are still susceptible to mumps, an overall vaccination rate of 96 percent is needed to prevent an outbreak" For Covid-19, to note from the first source again: "A vaccine that is able to reduce the severity of disease, even if it cannot prevent infection entirely, would obviously still have enormous public health value. Therefore, this is what trials target as their primary aim."
- gojomo 6y ago
  Yes and no. These vaccines have been formally tested for their ability to protect the recipient, & there is some unquantifiable risk that they'll still get harmless-to-themselves mild infections – especially nasal/mucosal/surface infections – that can still transmit to others. But it's reasonable to also expect the following to be shown when there's more time: * The milder infection makes such infections less transmissible (in terms of duration-of-infectiousness of quantity-of-sheddding) * such superficial infections in the vaccinated don't recur often, or as they recur become ever-milder – because the nasal/mucosal surfaces themselves eventually improve their immunity. So, an extra step is required to achieve the simplified idea of 'herd immunity', but the vaccines is still one step in that direction. So it is still very much the hope & eventual aim of these vaccines to keep enough people alive, with mild easily-recovered infections, that 'herd immunity' (and thus much-lower or almost non-existent rates of infection even in the unvaccinated) is reached.
  - acqq 6y ago
    > But it's reasonable to also expect ... - The milder infection makes such infections less transmissible (in terms of duration-of-infectiousness of quantity-of-sheddding) Neither reduced duration of infectiousness nor reduced quantity of shedding by definition protects the vulnerable. It can reduce the speed of spread, but that by definition doesn't even mean that a vaccinated person can visit their non-vaccinated or immune suppressed relative without the mask. For all we know the "quantity of shedding" has to be very low for transmission to provably not occur -- some experts estimate that a single droplet containing only 500 viruses is enough. To compare, the typical tests measure the presence of virus RNA starting with many millions in the sample and the tests do detect asymptomatic persons -- those who don't get sick now. > superficial infections in the vaccinated don't recur often From the studies of other coronaviruses it is known that infections do recur. And finally, we even know that even some percentage of people who get the vaccine become the disease later and are observably sick -- that's the difference to 100 to efficacy percentage (e.g. 5 of 100 who received the vaccine, or every 20th, if the efficacy is 95%). And we can also expect effectiveness (protection of the vaccine in the real world) to be lower than efficacy (reported from trials). In short, for all we know at the moment, the life will continue to be hard for those who don't get the vaccine and those whose immune system can't respond to the vaccine.