@Grant ********

, the vaccines detect the virus on certain characteristics. If those characteristics are not changed by mutation, then the vaccine will still be working. I guess doctors and virologists know this better than mathematicians.

@Grant ********

, there are more than 400 mutations of Covid-19 already. Each vaccine works for all the known mutations so far. But yes, there might happen some mutations sometimes in the future, the vaccines will not work for. Some vaccines will be easy to adjust to new monster mutations. Some vaccines will not be.

@Grant ********

, that's not true either. The vaccines being developed so far are effective to the known mutations of Covid-19.

@Lindsey *********

, that seems obvious, but no problem to find real sources on how vaccines basically work.

@Lindsey *********

, yes it is. If you have antibodies you are not getting sick and are not infecting others. Otherwise, no vaccine would ever work.

@Lindsey *********

, no, that's simply not true. The vaccines make your body make antibodies which prevent the virus from getting into your cells for reproduction.

@Emilio ********

, in theory, true and some embassies are telling people so. But do know any immigration office doing it in real life?

If O is listed as an option for retirement, you will have to ask the embassy if multi-entry non-O is valid under Covid-19 or only single-entry is available? Multi-entry non-O requires you to leave the country every 90 days. Single-entry requires you to apply for a visa extension 30 days before the expiry. However, extending a non-O over non-OA gives you the advantage of less requirements.

You will have to check the Embassy's website. Some embassies list both O and OA as options for retirement.

David Broadfoot, again, you are waste of time. You are misguiding people. If you want to obtain a work permit I guess you like to stay in Thailand. Then you will need both a work permit and visa/extension. Then please do not fool people into believing that there is no salary requirement.