It usually takes 3 to 6 days for a person to get symptoms of hand-foot-and-mouth disease after being exposed to the virus. This is called the incubation period.
Preheat oven to 400 degrees F. Cut off the brown ends of the Brussels sprouts and pull off any yellow outer leaves. Mix them in a bowl with the olive oil, salt and pepper. Pour them on a sheet pan and roast for 35 to 40 minutes, until crisp on the outside and tender on the inside. Shake the pan from time to time to brown the sprouts evenly. Sprinkle with more kosher salt (I like these salty like French fries), and serve immediately.
3. Place the Brussels sprouts in the boiling water and cook them for 10-15 minutes. Cook them until they're tender -- when they're ready, you should be able to stick a fork in them.. Roast the Brussels sprouts for 35-40 minutes or until they're tender. After 30 minutes, start checking to see if they're tender by piercing them with a fork. Shake the pan from time to time to ensure that they cook more evenly.