The virus needs someone to replicate inside, which is when mutations can occur. These are random and it's likely that most will get lost along the way, as they confer no advantage, compared to the former dominant strain that competes with them.
As fewer people get infected, this reduces the likely mutation potential. We're currently in a position where many countries are seeing the greatest levels of infection, so we see the opposite - the increased potential for mutations to be occuring in many isolated countries, many at their peak infection levels.
If we had sustained high infection levels, a new mutation would have the potential to out-compete the former dominant strain, as happened with the Kent variant.
Higher infection levels equals higher likelihood of new mutations and variants..
The vaccines prime our bodies to be vigilant for characteristics of the virus. If the mutations have not differed to lose most of these, the immunity will still protect us.
Some of the vaccines can be tweaked quite easily and quickly, should any variants be found to not be subject to the immune response that the vaccines have formerly given. At present, most of the world population hasn't had any vaccine protection, so adjustments, if needed, may happen before they get their first dose.
The good news has been that the variants so far still would seem to be subject to the several vaccines' immunity that we get.
What's uncertain to date is how long any of the immunity that we gain from the different vaccines last - monitoring is ongoing.
This virus doesn't mutate as frequently as the flu viruses do, for example. The prominence of mutations is due to the high volumes of people getting infected. If we lower infection volumes, we will reduce the mutation volume too. This should reduce the potential for any to fall outside of the scope of our immunity.
When we find the immunity duration, we'll take a judgement based on the need for recurrent vaccinations. The subsequent vaccinations could be of adjusted vaccines, that counter any mutation. People are likely in my opinion to get repeat vaccines for some years to come, as we do with flu. Poorer countries may sadly be more subject to longer term higher infection levels than us and could be sources for seeding of new infections here and other richer countries.
That we are primed to be alert to new variants is a good thing. Globally we will need to continue our evaluation of testing done on newly infected people, to sample its make-up with sufficient frequency. |
