COVID-19 booster, specifically a third vaccine dose, may lower protection against getting infected with the omicron variant again for some people — and there’s a reason why, new findings suggest. In contrast, two vaccine doses, followed by an initial omicron infection, may protect more against a second omicron infection than an extra jab, according to a preprint study published Nov. 1 to medRxiv, a server run by Yale, BMJ and Cold Spring Harbor Laboratory. This is due to a specific reaction within the immune system, researchers concluded. Here’s what the findings mean. “If you got infected with Omicron at any...