It is 9 months since vaccines were rolled out in the US.
61% have received at least 1 dose.
54% are fully vaccinated.
The ratio between cases and deaths should have increased by now.
(Fewer deaths per case = bigger ratio)
Thread 👇
One possibility is that there are still many people who are not vaccinated, and these figures represent infection & death among the unvaccinated subgroup.
And if the unvaccinated are predominantly over 65, it would mean more deaths. See NYT article👇
The above article states that in 11 states, at least 20% of older adults have not received even one dose.
The most logical explanation for the above graph is the combination of factors (older age group + being unvaccinated) existing in a large number of people.
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“Deaths have been concentrated among the unvaccinated. The CDC released studies showing that unvaccinated Americans were 4.6 times as likely to be infected, 10 times as likely to be hospitalized and 11 times as likely to die”
However, hospitals say the death rates have not come down, and that the age group has shifted to younger people. @jon_kamp writes that in Tampa General, the ICU patient’s age is only 46.
He finds that the share of deaths among <54 segment has increased to over 20%.
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“97% of COVID-19 deaths are in unvaccinated or partially vaccinated people” - report from Pennsylvania.
Death was 7.9 times more likely among these subgroups, when compared to fully vaccinated people.
In summary, it appears that even a relatively high rate of vaccination coverage will not bring down the death rate (as defined as the ratio of daily reported deaths / cases).
Reports indicate that most of these deaths are among those who have not had 2 doses of vaccine.
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What does this mean for the rest of the world?
Hybrid immunity is a potential solution: that is 1 dose vaccine among those who previously had COVID-19.
At least 2 antigen exposures will be required to keep deaths down, either by 2 dose vaccine or by hybrid immunity.
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The current % of vaccine coverage (2/1 dose):
UK 66/73
Canada 70/76
India 14/43
Vietnam 6.2/27
Zambia 1.6/1.7
Note: level of protection also depends on seroprevalence from natural infection. e.g. 80% seroprevalence was recently reported from unvaccinated people in Mumbai.
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Breakthrough infection rate is not provided for type of vaccine. Only overall number is given (13%, 81/614)
Antibody levels are seen to drop with time as expected.
Peak antibody levels are lower & the decline faster for covaxin, but this does not imply lower protection.
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The reason why a lower antibody level does not mean lower protection is that there are multiple components in the immune system that provide protection. Not all of them are measurable.
Besides, the study does not provide data that lower antibody level led to more infections.
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Multiple issues with the widely quoted NEJM Israel study on boosters
Long thread👇
1. Authors report a lofty reduction in infections & severe cases by a factor of 11.3 & 19.5 in the primary analysis, where rates are compared between boosted & non boosted groups.
2. In secondary analysis, this factor is down to 5.4. Secondary analysis compares rates within the SAME group, by timeframe. This is more believable not only because comparison is within the same group, but also because we know higher antibody levels reduce infection rates.
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Note: secondary analysis is available ONLY for infections, not severe cases.
In other words, we do not yet know if this 5.4-fold reduction in ‘infection’ will translate to reduction in hospitalisation/death later.
3. No mention of number of people who were hospitalised.
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Detailed graphical representation of the story of the US elementary school teacher who infected 12 of her masked students by reading aloud without mask.
Lessons:
1. Multiple factors have to be in place to prevent outbreaks
Large cohort of 673,676 vaccinated, 62883 past infection, & 42,099 vacc + past infection. The groups were matched to exclude confounding.
They looked at remote & recent past infection separately. Those who were infected in 2021 had greater protection than 1 year ago.
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The vaccinated group had a 27-fold greater risk of SYMPTOMATIC breakthrough infection compared to natural infection. The risk was 13-fold for ALL breakthrough infections.
A single dose of vaccine further increased the level of protection for those who had past infection.
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Audit of 281 COVID-19 deaths in Ernakulam showed that 98.2% of the deaths occurred among those who had not been (fully) vaccinated. i.e. only 1.8% of deaths were fully vaccinated.
The reason why children are easily able to get rid of the SARS-CoV-2 virus is due to a super-efficient innate immune system in their airways, as was hypothesised earlier (not from ‘less ACE2 receptors’).