Personally speaking, at this time I don't see the need for a healthy individual to get a 4th shot until and unless an omicron-specific version becomes available. It appears to me that the antibodies produced by the vaccine for the original covid virus are of limited benefit against omicron. It is my personal suspicion that it is the T and B cells that are primarily responsible for effectively combating omicron. It is my personal opinion this explains why a high percentage of vaccinated people can still contract omicron, yet the vast majority of the vaccinated have fairly minor symptoms that only last 1 to 3 days.
IF they can come up with one that is based on the same yearly flu shots, and not some new untested vaccine that the mRNA one is, then there will be a lot more positive reception to it. With the Omicron, they have time now to study it, break it down, and use it in a standard type shot.
I good percentage of the so-called anti vaxxxer crowd who are refusing the shots is doing so because mRNA is too new, and has had very little trial data, less than 10 years since conception, with onl a small handful of trials, mainly for HIV and AIDS testing that have been inconclusive. It isn't so much the immediate side effects, but the long term effects that are as of yet still unknown.
I do not want my kids getting these shots because there is very little data on how mRNA will affect their still developing bodies. They are both in their teens, prime time for growth of their adulthood parts. What if the mRNA triggers some abnormal growth, or lack of it? We don't know, and scientists don't know because there have been so few long term trials.
As for long term immunity, MMR, Polio and the like are a series of shots, but once given, they last a lifetime. Smallpox, pretty sure everyone over 55 has had one before they were phased out, but we are still better protected than those under 55 even though we have not received any boosters since the initial arm scar. A good well working vaccine should protect us for a very long time, and there are some good indicators that Omicron is the vaccine we need. Over time, we may catch a covid cold again, but nothing like what it originally was. Every mass killer virus eventually fades to what we see today, an occasional sickness, but one that the vast majority can get over. Spanish flu still exists and is one of the flu bugs that occasionally makes it's way into the annual shot.
Lets also not forget how many die each year due to flu, and not WITH flu but FROM flu. The one thing about Flu is not everyone tests for it when sick, mild cases never see a doctor for a test, they take some OTC meds, crawl into bed and get back to normal after a few days, with no record of having it in a database. When a person with (
insert co-morbitity) passes while also having the flu, it is marked as (
insert co-morbitity) not flu, so we really have no idea how many die with the flu from co-morbitity. In 2017, I would not be surprised if the actual numbers far exceeded the 2020 numbers for Covid. 2017 was a bad year for Flu.