I spent time with my fiancée's daughter this weekend. She's an RN / works with epidemiologists re.: protocols on drug trials (vaccines/ therapeutics).
Obesity is a major factor (she's seen BMI's that exceed 50....25 is the borderline for Overweight).
But that doesn't explain why people younger than 40, 30 get it. Genetics? Predisposition? No answers yet.
But if you say you're young and healthy, you probably are running a much lower risk than those of us over 65, male, pre-existing and if your obese (you're basically toast...surprised Chris Christy recovered). On the other hand if the genetics show that you're at a greater risk and if you catch the wrong viral load you've got a long haul if you survive you're playing Russian Roulette with your life...as well as your family and the unfortunate health care workers who will try to save your life.
MO