[mzltest]

The new variants arise because only a fraction of the World population is currently immunized either because they have been vaccinated or because they have already contracted the virus and recovered from it. The vast majority (in terms of billions) aren't still. So SARS-CoV-2 is busy generating those variants inside those billions of potential hosts.
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Agreed.

We are on the race and mutations do occur in a low rate every time the virus spreads,and these mutations might develop strains that are harder to get rid of.Though the rate is low,but the massive infected hosts have compensating the low mutation rate and showing up new variations.So if we are able to keep the active infected and not-protected hosts to a controllable number,the new strains,at least,show slower and giving us more time to focus on the long term solutions.And one important approach is vaccination.

However as I pointed out previously,any kind of vaccine can not guarantee protection,and as far as I know,if a vaccine have a >50% protection rate it can be approved for emergency use.In a video(https://www.youtube.com/watch?v=7OLpKqTriio)it is said you need at least 60% protected people to supress the virus but I think we need more considering other issues like mutation.And all of these should happen in the same popular strain.

And yes,though here we do not use imported vaccines,I knew there are some blood clotting cases using AZ.I prefer not to comment on the issues but at least if you don't want to take the risk,you should follow the basic santiziation standards - at least don't spread the virus.