> Whatever natural immunity you got nearly 3 years ago is long since useless
This is factually incorrect. You don't have perhaps protection against infection, nor probably symptomatic disease, but there is working natural immunity, in the form of immune memory and cell based immunity (T lymphocytes).
That is far, far more resistant to variants than humoral (antibody based) immunity, mainly because only antibodies neutralizing the S protein are able to prevent infection (so more vulnerable to mutations).
Cell based immunity can't prevent infection, and can not necessarily prevent disease (as in, having fever, cough...), but it is very effective in dampening the effect of infection (either through recruitment of other immune cells, or by killing infected cells). Memory T and B cells generally last quite a lot of years (and with SARS-CoV-2, up to two years at least), so this memory is long-lasting.
Where is the T cell immunity? People are on their fourth and fifth infections now. If there were strong T cell protection we wouldn't see constant reinfection.
T cells will save us has been a big coping strategy from people trying to claim the pandemic is over too soon. Hucksters like Monica Ghandi have been saying T cells will save us for years now.
When... when will it happen I ask. Over a million dead bodies and people still racking up infections. Back up to an average of 500 people dying a day even in our summer lull right now, and it's climbing again.
Look at the entire continent of Africa. A high seroprevalence of SARS-COV-2 antibodies, and yet these mostly underdeveloped nations have a much lower death rate even if you count excess deaths due to poor reporting than the US with supposedly all the best to fight it. My thought is that statistically Africans are thinner and get outdoors more than their obese, diabetic, and hypertension-suffering peers in the US and Europe sitting on their couches. I tested 113 a full year after my COVID-19 infection on an IgG test when 15 or over is considered a positive antibody test. I am going to get tested again when I return from Saudi back to the US a full two years after my infection. I bet I am still in the 80s or thereabouts. And I have not had a second infection. I am fit, do not suffer from hypertension or diabetes, and I had COVID. These are solid, scientific factors that put me in a lower risk category even if I get COVID again.
This is factually incorrect. You don't have perhaps protection against infection, nor probably symptomatic disease, but there is working natural immunity, in the form of immune memory and cell based immunity (T lymphocytes). That is far, far more resistant to variants than humoral (antibody based) immunity, mainly because only antibodies neutralizing the S protein are able to prevent infection (so more vulnerable to mutations).
Cell based immunity can't prevent infection, and can not necessarily prevent disease (as in, having fever, cough...), but it is very effective in dampening the effect of infection (either through recruitment of other immune cells, or by killing infected cells). Memory T and B cells generally last quite a lot of years (and with SARS-CoV-2, up to two years at least), so this memory is long-lasting.