@ Mystic N_eg
“Some people are getting vaccinated who have already had “Covid-19” (take this to mean they exhibited the collection of flu type symptoms associated with infection with SARS-CoV2 and they were also tested as SARS-CoV2 positive) and recovered”
Or perhaps they had very low oxygen levels, a dense white shadow in both lungs on their X-rays, a particular pattern of low platelets and specific white blood cells, and very high marker of clotting called D-Dimer. This is a clinical pattern doctors all over the world. Perhaps they are scared having had it and want to protect themselves as best they perceive they can.
There are studies from long before this pandemic showing people being reinfected with coronaviruses (the 4 causing common cold and endemic in the population) from 6 months to ten years later. It isn’t known if immunity is conferred by having become infected though there is some evidence that it does. There are also cases of reinfection. If immunity is conferred it isn’t known how long that will last. Of course this also applies to the vaccine. There are a lot of unknowns.