This question will resolve positive if in the opinion of the judges the scientific consensus is that getting all currently-recommended vaccines, including the two original vaccines and the Omicron booster, decreases risk of the new variant by less than 50%.
This is question #43 in the Astral Codex Ten 2023 Prediction Contest. The contest rules and full list of questions are available here. Market will resolve according to Scott Alexander’s judgment, as given through future posts on Astral Codex Ten.
The resolution criterion is very vague and the discussion on ACT doesn't help. Escape normally refers to immunity against infection. So, not hospitalizations or deaths. But recent variants already escape current vaccines substantially.