Neither of these things are guaranteed to happen if you get the flu vaccine when you are sick, but they are possibilities. If you have just a mild illness, there is no reason to wait to get vaccinated.
Early in the day, let roast stand at room temperature at least 1 hour before cooking. Preheat oven to 375 degrees. Rub meat ... the outside and rare in the middle. Meat will be very brown ... stand at room temperature for at least one hour.
1 Preheat oven to 425 degrees F for 15 minutes. 2  Place the roast in the oven and immediately reduce the temperature down to 200 degrees F. 3  Roast for about 4 hours or until the meat is falling-apart tender (cooking time will vary depending on the size of the roast).