Report of vaccinated MBBS students picking up SARS-CoV-2 virus; such clusters have been occurring.
This is not “fear-mongering” (as some allege), but an important message to the public that they can’t discard precautions just because they are vaccinated. @GargiRawat@sjacobtalk
Such measures, taken by several nations in 2020, were justifiable due to a fear of the unknown. Now that we have 21 months of data, it is time to sit down & see if they made any difference.
We must also not forget that it is the SAME virus, regardless of fancy Greek names.
2/4
The problem with variants of concern is two-fold.
1. They take a long time to show their true colours. Thus, by the time they are declared as VOC, modern travel would have taken them all around the world.
2. Even a single introduction is enough to infect a whole country.
3/4
This thread shows instances of fully vaccinated people picking up (and spreading) infections. Apart from very low baseline risk, this is one more good reason why universal COVID vaccination for healthy children isn’t advisable. See UK study linked below. @GKangInd@doctorsoumya
This thread in response to query by @FaruquiNeha based on an article by @Craig_A_Spencer that essentially states vaccinated people are less likely to be infected.
While that statement is true, it doesn’t address the whole issue.👇
It can be positive, which means those with advantageous mutations get selected over others, leading to an increase in its population. Example is delta variant in the case of SARS-CoV-2 virus.
Negative selection pressure is 👇
2/
Negative selection pressure also occurs in evolution, it is basically the force that gets rid of the “seconds” or “imperfect products” or those who have genetic changes that are deemed unfit for long term survival of the species.
3/
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.
3/
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.
2/
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.
3/