🔹Longer 4 month interval between doses generated stronger immune response (mRNA, humoral) than 1 month (16 vs. 4 weeks)
This ~explains the quick waning in nations that used short gap
🔹1 dose might be enough for those who had prior infection (2nd dose did not add much)
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The study strengthens the original concepts that:
1. Single dose might suffice for those with prior infection
2. Vaccination for COVID-19 is basically a 2-step process, with a 3rd encounter not adding anything substantial. (The “booster dose” might have served as 2nd dose)
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In other words, the first 2 doses of mRNA vaccine, taken “too close together” (3-4 weeks), might have been interpreted by the body as a SINGLE dose.
That will explain why the 3rd mRNA dose generated substantial rise in antibody level afterwards, during the booster campaign.
3/
Note that the US used a 3 week gap for Pfizer vaccine; this was based on the original trials. This gap now seems to have been TOO SHORT to generate an optimal immune response.
This study used a 16 week gap (~4 months) and finds a remarkable improvement over the 4 week gap.
4/
The study also shows clearly that a second dose does not ADD to the immune response in someone with prior infection.
Previous studies had shown that cellular immunity also does not further increase after the 1st dose in these individuals.
(References in the Cell paper)
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The study also shows “natural immunity” boosted by 1 vaccine dose declines at a slower rate than 2-dose vaccination (naive) - even after using the longer gap.
This suggests that the best immune protection is when a single dose vaccine is given to someone with past infection.
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The authors write:
“The strong humoral response seen with this extended schedule is longer-lasting than immune responses following the authorized schedule, the need of a 3rd dose might be delayed and this could have significant implications regarding control of COVID-19”
7/7
Unfortunately, superficial reading & blindly following the narrative of published articles leads the reader to arrive at wrong assumptions.
One MUST take the time & look at the data presented, independently, using basic tools. I have added my notes for those interested.
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❗️The hospitalisation trends at any time must be interpreted in the context of the prevailing vaccination rates. I have used vaccination rates at the beginning of each time period.
It is only basic math, and my notes are self explanatory.
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The fact that people are vaccinated will not make much difference when there is a massive viral load in the air as people talk, sing & spend a long time together in a closed space.
(Mucosal immunity doesn’t last long after vaccination)
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Similar story from Germany recently. Dr Christian Drosten retweeted this story.
Just to show that “3G” will not work against the SARS-CoV-2 virus. See thread for details.
The 3rd dose used were AstraZeneca, Pfizer, Moderna, Valneva (French inactivated vaccine), J&J, CureVac (mRNA), NovaVax (subunit, Spike protein).
They measured antibody level & T cell response after this dose, and compared between various combinations. See paper for graphs.
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The first thing we must remember is that antibody level is not an exact correlate of how much protection is achieved.
In other words, if “double” the antibody level is produced by a particular vaccine, it does not mean that symptomatic infection rate will be “cut in half”.
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The obvious theoretical question that comes with Omicron is that the extraordinary number of mutations in certain key areas could potentially alter the target of these antibodies to a point where the “missiles miss their target”.
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Particularly because these mutations occur in a part of the spike protein that binds to the ACE-2 receptor, called the RBD.
However, there are several parts of the spike protein that remain unchanged, which means that the ENTIRE TARGET cannot be changed by the virus.
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🔹Neutralising antibody levels correlate with protection from infection in the nose and throat, while T cell Immunity guards against organ damage and severe disease.
Will explain below 👇
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🌳 Imagine the spike protein to be a mango tree. Antibodies target the fruit, while T cells target large branches. Mutations are like mangoes that change their appearance. Hence, a few antibodies can get ‘fooled’.
But the branches are unchanged; hence T cells work as usual.
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Updates from this week’s Tuesday COVID-19 meeting that I have been chairing since the onset of the pandemic.
This week we audited 105 deaths, and found something significant:
🔹Unvaccinated individuals were 17.6 times more likely to die, compared to vaccinated.
More updates👇
In a Kerala village of 15,000 (adult) population, only 38 were unwilling to take vaccine.
🔹This translates to a vaccination acceptance of 99.8%
Note: we don’t have mandates here.
The few remaining unvaccinated were recently or currently infected (90 day gap advised)
2/2
Tuesday COVID-19 meeting update #3
Although “overall CFR (case fatality rate) is low”, doctors pointed out that this is a misleading statement, underestimating the destructive power of the virus. It is like saying “everyone in India is 28 years old”