The polio vaccine provides sterilizing immunity, meaning that once you’ve had the vaccine you can no longer get polio. You are 100% immune.
What ? Totally wrong disease to use as an example of “sterilizing immunity”.
Well there are two types of polio vaccine.
Salk, and Sabine.
Sabine is attenutated virus . Which means that you actually get a polio infection from it, but its a very weak form of it. But there is recombination happenning, and theres a tiny tiny chance of it regaining its strength. recently the use of sabine has created more detected cases of polio than wild cases . This is taken orally as it causes the infection in the intestines, where all polio infections start.
Salk is an injection and it just prevents the neurological damage that polio causes.
You can still get the polio in your intestines, because the injection hasn’t trained your immune system to fight off the intestinal infection.
Tetanus, and pertussis and most vaccines against bacteria are equally only to prevent the serious illness, not the infection.
BCG for TB trains your body to fight TB in your ordinary flesh, eg skin and muscle… but its not so good at preventing infection in lining of your lung.
The myth that the covid19 is going to be similar to influenza can be explained as a myth.
The SARS2 virus is only attacking the ACE2 receptor. This receptor requires a very precise key , the spike protein is that key. It can’t really evolve to attack other receptors in humans, as a chance to give it a long shot at attacking another receptor should totally reduce its chance of entering via human ACE2… it could evolve by jumping species, where maybe the receptor is slightly different and the species jumping provided the stepping stones.
Influenza enters cells using generic weaknesses in the cell membrane structures, so it has less trouble evolving. If it randomly evolves to attack a new site at some tiny chance, its not lost much chance to attack the old sites. So it smoothly refines a new protein for entering the human cell… So statements like “Covid19 cannot be eradicated” should be treated as myth , it seems clear that the entry via the ACE2 receptor is why covid19 is a deadly common cold… its not the payload , its the spike protein… which can’t evolve. So the SARS2 with the ACE2 receptor attack can be wiped out, as was the SARS 1 …