This will change once they have boosted the 50+ population, or that's at least how it usually works. The Omicron targeted vaccines should be ready by then, so we are not necessarily out of luck. I'm 49.
Because it protects you and others around you from disease. Cowards will make up lies and excuses for not taking it, though. I suppose you have to decide who you trust, your doctor, or internet trolls. My guess is, if you ask your doctor, he or she will recommend you take it.
honestly, it's just not worth arguing- some folks are going to be permanently convinced that the case for vaccination is much stronger than it really is. Like I said in other comments: the medical researcher community moved on and no longer believes that vaccines were nearly as effective as originally believed, for any criterion. We certainly aren't ever going to reach ongoing herd immunity so the most reasonable approach now is to identify people at greatest risk and spend more resources protecting them.
The Centers for Disease Control and Prevention recommended Thursday that millions of eligible Americans, including those as young as 12, get an updated omicron-targeting booster shot to bolster defenses against serious illness and death during a potential fall or winter rise in covid-19 cases.
If you doctor is telling you not to get the booster, you need a better doctor.
BA.5 avoids the immunity you gained from Delta, Alpha, and the original.
If you got COVID-19 this July-ish (when BA.5 was biggest), maybe you don't need a vaccine update. But given how much the virus has evolved, it only makes sense to update your body to the newest version that's out there.
If the next big strain is from the BA.5 lineage (or closely related lines like Omicron), having your body trained on the new proteins / RNA should help a lot.
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Fortunately, it's not as big a deal because original strain / original vaccine looks like it still prevents hospitalization and deaths. So this is strictly about reducing the spread of Omicron / BA.5 and related substrains.
BA.5 is targeted and ready. The only question left is one of policy and distribution.