3 ms·

What is your source for reinfection rate less than 1%? It seems much higher based on the recent second wave in Manaus [0]. [0] https://www.cidrap.umn.edu/news-

What is your source for reinfection rate less than 1%? It seems much higher based on the recent second wave in Manaus [0]. [0] https://www.cidrap.umn.edu/news-perspective/2021/01/variant-covid-among-triggers-grim-surge-manaus-brazil https://www.cidrap.umn.edu/news-perspective/2021/01/variant-...

LeoNatan25 6y ago
Isn’t that an antibody-escaping variant? Existing vaccines aren’t very efficacious for that variant either.
- LeoNatan25 6y ago
  My comment is being downvoted by an emotional crowd, it seems, but read this: https://www.biorxiv.org/content/10.1101/2021.01.15.426911v1 https://www.biorxiv.org/content/10.1101/2021.01.15.426911v1 "Our experiments indicate that these variants, and potentially others that carry K417N/T, E484K and N501Y mutations, can reduce the neutralization potency of vaccinee plasma." Preprint, not peer-reviewed, but still concerning.
  - handoflixue 6y ago
    TL;DR: It doesn't currently seem like a problem, but it is definitely a topic worth keeping an eye on. "The vaccine generated a weaker immune response against the South African strain, but the antibodies remained above levels that are expected to be protective against the virus, the company said, adding the findings may suggest “a potential risk of earlier waning of immunity to the new B.1.351 strains.” “Out of an abundance of caution and leveraging the flexibility of our mRNA platform, we are advancing an emerging variant booster candidate against the variant first identified in the Republic of South Africa into the clinic to determine if it will be more effective to boost titers against this and potentially future variants,” Moderna CEO Stephane Bancel said in a statement." Source: https://www.cnbc.com/2021/01/25/covid-vaccine-moderna-working-on-covid-booster-shots-for-south-african-strain.html https://www.cnbc.com/2021/01/25/covid-vaccine-moderna-workin... Source for my source, because he posts a pretty solid round-up of recent research and well-cited sources every Friday: https://thezvi.wordpress.com/2021/01/28/covid-1-28-muddling-through/ https://thezvi.wordpress.com/2021/01/28/covid-1-28-muddling-...
Exmoor 6y ago
Here's a source for the reinfection rate. I've seen a few studies that all came to the < 1% conclusion: https://www.medrxiv.org/content/10.1101/2021.01.15.21249731v1 https://www.medrxiv.org/content/10.1101/2021.01.15.21249731v... The Manaus data is interesting. The basis for assuming there's reinfection happening seems to be a seroprevalence survey done over the summer which estimated 76% of the population had antibodies to the virus. The accuracy of that survey has been called into question for a variety of reasons. The survey was done through blood donors and apparently they incentivized blood donation by offering people the results of their antibodies test as part of donation. Since testing capacity during peak infection was limited, this would give people who thought they might have had the virus (and likely did) incentive to donate blood and made the sample not nearly as random as it was presented to be.
- timr 6y ago
  > The basis for assuming there's reinfection happening seems to be a seroprevalence survey done over the summer which estimated 76% of the population had antibodies to the virus. The accuracy of that survey has been called into question for a variety of reasons. This is exactly correct. Extrapolating from the Manaus seroprevalence paper is scientifically tenuous, at best. They say so in the Lancet commentary cited in the CIDRAP piece cited by OP: "In the Lancet report, experts said four factors may be at play, some possibly related. First, scientists might have overestimated the attack rate for the first surge, and infections might have been below the herd immunity threshold" > The survey was done through blood donors and apparently they incentivized blood donation by offering people the results of their antibodies test as part of donation. Since testing capacity during peak infection was limited, this would give people who thought they might have had the virus (and likely did) incentive to donate blood and made the sample not nearly as random as it was presented to be. Not just that, but if you read the paper carefully, you'll see that they've applied a number of fairly arbitrary "corrections" to the data, which pull the seroprevalence from an observed 20% range up to the cited "76%" number (Figure 2A in this link): https://science.sciencemag.org/content/371/6526/288 https://science.sciencemag.org/content/371/6526/288 While any of these adjustments might be individually merited, when you see a >300% aggregate "adjustment" to the raw data, it should make you very skeptical about any claims made with that data. Particularly when the raw data is below the likely herd-immunity threshold, and has been "corrected" to be above it. More simply: the most likely conclusion is that the original paper was wrong. This is perfect example of bad science being propagated by journal title and headline. Whomever wrote that (IMHO, terrible, editorialized) CIDRAP piece didn't bother to read the original data, and just took the first paper's claim at face value. Journalists have been (and continue to be) insufficiently skeptical when it comes to Covid science -- except when it suits the narrative they're trying to create. If a paper supports their desired narrative, any half-baked, highly implausible claim is treated as worth serious consideration. If a paper conflicts with their claim, no counterargument is too implausible to be considered.

LeoNatan25 6y ago

Isn’t that an antibody-escaping variant? Existing vaccines aren’t very efficacious for that variant either.

LeoNatan25 6y ago
My comment is being downvoted by an emotional crowd, it seems, but read this: https://www.biorxiv.org/content/10.1101/2021.01.15.426911v1 https://www.biorxiv.org/content/10.1101/2021.01.15.426911v1 "Our experiments indicate that these variants, and potentially others that carry K417N/T, E484K and N501Y mutations, can reduce the neutralization potency of vaccinee plasma." Preprint, not peer-reviewed, but still concerning.
- handoflixue 6y ago
  TL;DR: It doesn't currently seem like a problem, but it is definitely a topic worth keeping an eye on. "The vaccine generated a weaker immune response against the South African strain, but the antibodies remained above levels that are expected to be protective against the virus, the company said, adding the findings may suggest “a potential risk of earlier waning of immunity to the new B.1.351 strains.” “Out of an abundance of caution and leveraging the flexibility of our mRNA platform, we are advancing an emerging variant booster candidate against the variant first identified in the Republic of South Africa into the clinic to determine if it will be more effective to boost titers against this and potentially future variants,” Moderna CEO Stephane Bancel said in a statement." Source: https://www.cnbc.com/2021/01/25/covid-vaccine-moderna-working-on-covid-booster-shots-for-south-african-strain.html https://www.cnbc.com/2021/01/25/covid-vaccine-moderna-workin... Source for my source, because he posts a pretty solid round-up of recent research and well-cited sources every Friday: https://thezvi.wordpress.com/2021/01/28/covid-1-28-muddling-through/ https://thezvi.wordpress.com/2021/01/28/covid-1-28-muddling-...

Exmoor 6y ago

Here's a source for the reinfection rate. I've seen a few studies that all came to the < 1% conclusion: https://www.medrxiv.org/content/10.1101/2021.01.15.21249731v1 https://www.medrxiv.org/content/10.1101/2021.01.15.21249731v... The Manaus data is interesting. The basis for assuming there's reinfection happening seems to be a seroprevalence survey done over the summer which estimated 76% of the population had antibodies to the virus. The accuracy of that survey has been called into question for a variety of reasons. The survey was done through blood donors and apparently they incentivized blood donation by offering people the results of their antibodies test as part of donation. Since testing capacity during peak infection was limited, this would give people who thought they might have had the virus (and likely did) incentive to donate blood and made the sample not nearly as random as it was presented to be.

timr 6y ago
> The basis for assuming there's reinfection happening seems to be a seroprevalence survey done over the summer which estimated 76% of the population had antibodies to the virus. The accuracy of that survey has been called into question for a variety of reasons. This is exactly correct. Extrapolating from the Manaus seroprevalence paper is scientifically tenuous, at best. They say so in the Lancet commentary cited in the CIDRAP piece cited by OP: "In the Lancet report, experts said four factors may be at play, some possibly related. First, scientists might have overestimated the attack rate for the first surge, and infections might have been below the herd immunity threshold" > The survey was done through blood donors and apparently they incentivized blood donation by offering people the results of their antibodies test as part of donation. Since testing capacity during peak infection was limited, this would give people who thought they might have had the virus (and likely did) incentive to donate blood and made the sample not nearly as random as it was presented to be. Not just that, but if you read the paper carefully, you'll see that they've applied a number of fairly arbitrary "corrections" to the data, which pull the seroprevalence from an observed 20% range up to the cited "76%" number (Figure 2A in this link): https://science.sciencemag.org/content/371/6526/288 https://science.sciencemag.org/content/371/6526/288 While any of these adjustments might be individually merited, when you see a >300% aggregate "adjustment" to the raw data, it should make you very skeptical about any claims made with that data. Particularly when the raw data is below the likely herd-immunity threshold, and has been "corrected" to be above it. More simply: the most likely conclusion is that the original paper was wrong. This is perfect example of bad science being propagated by journal title and headline. Whomever wrote that (IMHO, terrible, editorialized) CIDRAP piece didn't bother to read the original data, and just took the first paper's claim at face value. Journalists have been (and continue to be) insufficiently skeptical when it comes to Covid science -- except when it suits the narrative they're trying to create. If a paper supports their desired narrative, any half-baked, highly implausible claim is treated as worth serious consideration. If a paper conflicts with their claim, no counterargument is too implausible to be considered.