The mine in question had 44 employees. The sample size is thus a bit small, the mine is probably not well-ventilated, and the working conditions are not good fo

The mine in question had 44 employees. The sample size is thus a bit small, the mine is probably not well-ventilated, and the working conditions are not good for health in general. Of course, it's bound to happen that eventually a COVID variant emerges against which a booster shot becomes required,so this might or might not hint at something greater.