No waning of immunity against severe disease: New York data NEJM
Note the effectiveness is calculated by comparing with unvaccinated group, which is gradually acquiring immunity from natural infection. Hence, there will be a decrease in the difference as time moves forward.
Authors believe that factors such as antigen availability, type of antigen-presenting cells, and cytokine milieu – might influence the type of memory formed.
Note: T cell memory cells are of multiple categories, not all of which are detected in peripheral blood.
2/
Some memory cells live in tissue and others in lymph nodes.
This study looked only at peripheral blood, and hence is not a description of T rm or T cm memory cells.
T rm’s live in tissues and do not move out. They defend tissues (e.g. lungs & mucosa) when an attack occurs.
3/
When a group under observation has a fixed advantage at the outset.
In heart transplantation VS non heart transplantation studies, this bias was first described (those who got the transplant had the opportunity to survive till they got operated)
2/
That is, the transplanted group were the healthier of the lot, they survived longer than those who died while waiting for surgery.
This was projected as an apparent outcome of transplant in some studies.
3/
Please note the diagram only presents an outline, not the whole thing.
Neutralising antibodies form only a tiny fraction of our TOTAL antibody response. Most antibodies are produced AFTER the attack occurs, helping eliminate virus.
(Labs measure Ab’s ALREADY in circulation)
2/
In other words, neutralising antibodies aren’t everything.
And, importantly, a “loss of neutralisation” (‼️🔴alarmist language that lab researchers love to use while describing their work to a clueless public) doesn’t mean “we have lost against the virus”.
3/