1. Antibodies fade after COVID-19 infection. Does that mean natural immunity fades? How strong will vaccine induced immunity be?

That the antibody response fades over time after COVID infections was already known from a large body of literature.

2. However, it is also true that antibody response is not the only response our immune systems have in response to infection, and these other immune responses (e.g. the production of specific T-cells) appears to be quite long lasting. You can see this in the fact

3. that despite an estimated 750 million worldwide to date after 10 months living with the virus, we have seen only a handful of reinfections. If the virus is like other corona viruses in its immune response, recovery from infection will provide lasting protection against