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GP's statement contradicts the scientific literature - vaccination does reduce viral load of subsequent infection, and consequently reduces transmission [1]. H

GP's statement contradicts the scientific literature - vaccination does reduce viral load of subsequent infection, and consequently reduces transmission [1]. However folks should be aware that immunity acquired through natural infection is robust and durable, and also has the same effect of reducing viral load and transmission [2]. It has been documented that people with asymptomatic infection will clear the virus quickly compared to those who are symptomatic [3]. Recent meta-analyses [4] and large population serological studies [5] have estimated the asymptomatic proportion lower bound to be at least ~33%, and the upper bound to be ~65% (even higher for young adults). Considering recent evidence that cases may be massively under-reported, the true asymptomatic proportion could be even higher than suggested [6]. Taken together, these results imply that a majority of the population has been already exposed to the virus, and either through natural infection or vaccination has acquired some degree of immunity that reduces the transmission of the virus. Analogous to antibiotic resistance, vaccine resistance can evolve if vaccines are used indiscriminately [7][8][9][10]. So the benefits of compulsory mass vaccination may not outweigh the risks of such a policy, given the current state of affairs. > so why all the fuss to force people to get vaccinated? It is an important question with tremendously complex factors that go beyond the expertise of most lay people. [1] Initial report of decreased SARS-CoV-2 viral load after inoculation with the BNT162b2 vaccine https://www.nature.com/articles/s41591-021-01316-7?origin=app https://www.nature.com/articles/s41591-021-01316-7?origin=ap... [2] Longitudinal analysis shows durable and broad immune memory after SARS-CoV-2 infection with persisting antibody responses and memory B and T cells https://www.cell.com/cell-reports-medicine/fulltext/S2666-3791(21)00203-2 https://www.cell.com/cell-reports-medicine/fulltext/S2666-37... [3] The Natural History and Transmission Potential of Asymptomatic Severe Acute Respiratory Syndrome Coronavirus 2 Infection https://www.sciencedirect.com/science/article/pii/S2666524720301725 https://www.sciencedirect.com/science/article/pii/S266652472... [4] The Proportion of SARS-CoV-2 Infections That Are Asymptomatic https://www.acpjournals.org/doi/full/10.7326/M20-6976 https://www.acpjournals.org/doi/full/10.7326/M20-6976 [5] Estimating the asymptomatic proportion of SARS-CoV-2 infection in the general population: Analysis of nationwide serosurvey data in the Netherlands https://link.springer.com/article/10.1007/s10654-021-00768-y https://link.springer.com/article/10.1007/s10654-021-00768-y [6] Evaluating the massive underreporting and undertesting of COVID-19 cases in multiple global epicenters https://www.sciencedirect.com/science/article/pii/S253104372030129X https://www.sciencedirect.com/science/article/pii/S253104372... [7] Risk of rapid evolutionary escape from biomedical interventions targeting SARS-CoV-2 spike protein https://pubmed.ncbi.nlm.nih.gov/33909660/ https://pubmed.ncbi.nlm.nih.gov/33909660/ [8] Can we predict the limits of SARS-CoV-2 variants and their phenotypic consequences? https://www.gov.uk/government/publications/long-term-evolution-of-sars-cov-2-26-july-2021 https://www.gov.uk/government/publications/long-term-evoluti... [9] Why does drug resistance readily evolve but vaccine resistance does not? https://royalsocietypublishing.org/doi/pdf/10.1098/rspb.2016.2562 https://royalsocietypublishing.org/doi/pdf/10.1098/rspb.2016... [10] The adaptive evolution of virulence: a review of theoretical predictions and empirical tests https://pubmed.ncbi.nlm.nih.gov/26302775/ https://pubmed.ncbi.nlm.nih.gov/26302775/

makomk 5y ago
Covid-19 vaccination used to reduce viral load of subsequent infections. Unfortunately, this doesn't seem to work with the current Delta variant - both the CDC in the US and PHE in the UK have released studies finding that the viral load of vaccinated and unvaccinated people is basically the same. They're also not so effective at stopping people from catching the Delta variant, and when you combine that with its higher infectivity it's basically impossible to get herd immunity using them.
- autoexec 5y ago
  Even in the case of the delta variant vaccinated people who get infected are more likely to have reduced symptoms (if they have any noticeable symptoms at all). That means a lot less coughing up huge plumes of virus over great distances. Nothing is perfect, but in the end the vaccines increase your odds of not being infected while decreasing your odds of spreading the virus. Herd immunity may not be reached but we can drastically reduce deaths and serious illness. That's already a win for vaccines.
- dubyah 5y ago
  Round 13 of the Imperial College REACT-1 study did still indicate an average lower viral load(higher Ct values) in vaccinated individuals.
- rossriley 5y ago
  No this is extremely misleading, the misquote you are using applies only to breakthrough infections, but the vaccines themselves are highly effective at preventing infection and thus breakthrough infections are very rare in vaccinated individuals. Should you happen to not mount a robust immune response despite being vaccinated then at that point you will have a viral load similar to an unvaccinated person, but the good news is even if this is the case you will still have much less severe disease outcomes than an unvaccinated person. The vaccines are incredibly effective against all current variants.
  - Amezarak 5y ago
    There have been > 111k breakthrough infections in the US alone through the end of July. The CDC stopped tracking them unless they resulted in hospitalization or death, but we can still look at the data from the 35 states still tracking it. It is fair to say that vaccination reduces the chance of infection. "Very rare", however, is not how I would characterize it. https://www.bloomberg.com/news/articles/2021-07-30/cdc-scaled-back-hunt-for-breakthrough-cases-just-as-the-delta-variant-grew https://www.bloomberg.com/news/articles/2021-07-30/cdc-scale... Data from Israel suggests that efficacy may be much lower than initially believed, but still much better than nothing. https://www.sciencemag.org/news/2021/08/grim-warning-israel-vaccination-blunts-does-not-defeat-delta https://www.sciencemag.org/news/2021/08/grim-warning-israel-...

makomk 5y ago

Covid-19 vaccination used to reduce viral load of subsequent infections. Unfortunately, this doesn't seem to work with the current Delta variant - both the CDC in the US and PHE in the UK have released studies finding that the viral load of vaccinated and unvaccinated people is basically the same. They're also not so effective at stopping people from catching the Delta variant, and when you combine that with its higher infectivity it's basically impossible to get herd immunity using them.

autoexec 5y ago
Even in the case of the delta variant vaccinated people who get infected are more likely to have reduced symptoms (if they have any noticeable symptoms at all). That means a lot less coughing up huge plumes of virus over great distances. Nothing is perfect, but in the end the vaccines increase your odds of not being infected while decreasing your odds of spreading the virus. Herd immunity may not be reached but we can drastically reduce deaths and serious illness. That's already a win for vaccines.
dubyah 5y ago
Round 13 of the Imperial College REACT-1 study did still indicate an average lower viral load(higher Ct values) in vaccinated individuals.
rossriley 5y ago
No this is extremely misleading, the misquote you are using applies only to breakthrough infections, but the vaccines themselves are highly effective at preventing infection and thus breakthrough infections are very rare in vaccinated individuals. Should you happen to not mount a robust immune response despite being vaccinated then at that point you will have a viral load similar to an unvaccinated person, but the good news is even if this is the case you will still have much less severe disease outcomes than an unvaccinated person. The vaccines are incredibly effective against all current variants.
- Amezarak 5y ago
  There have been > 111k breakthrough infections in the US alone through the end of July. The CDC stopped tracking them unless they resulted in hospitalization or death, but we can still look at the data from the 35 states still tracking it. It is fair to say that vaccination reduces the chance of infection. "Very rare", however, is not how I would characterize it. https://www.bloomberg.com/news/articles/2021-07-30/cdc-scaled-back-hunt-for-breakthrough-cases-just-as-the-delta-variant-grew https://www.bloomberg.com/news/articles/2021-07-30/cdc-scale... Data from Israel suggests that efficacy may be much lower than initially believed, but still much better than nothing. https://www.sciencemag.org/news/2021/08/grim-warning-israel-vaccination-blunts-does-not-defeat-delta https://www.sciencemag.org/news/2021/08/grim-warning-israel-...