One thing I find curious about COVID after years of following research. We know that incidental contact can cause infections. Studies have tracked outdoor infections and infections after spending an hour or two in restaurants and planes. And yet when someone in a household is sick, a study found the secondary infection rate was little better than 50/50 within the household (0.55). In my own household, I got COVID once and my wife didn't, and vice versa. (Of course, we isolated, but still...)