I would recommend the 2nd booster if you are more than 4-6 months from your 3rd shot, you are age 50+, you tolerated the previous shots well, and you are concerned about the BA.2 wave where you live, or that it’s getting legs as you are trying to decide. Or if you are traveling or have plans that would put you at increased risk.
It can certainly be deferred, but the question is when is the right time, and whether an Omicron-specific vaccine will have any advantage over a 2nd booster directed at the original strain. The data from 2 animal models (macaques and mouse models) suggests there may not be advantage of the Omicron-specific vaccine but that may not correlate with its effect in people. From my discussions with FDA, it is not likely the Omicron-specific vaccine will be available before late May or June. So you can factor that uncertain added benefit and timeline into your decision.
