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.
CHOOSE APPROPRIATE COOKING METHOD. Most roast beef recipes call for cooking roasts in a moderately hot oven, but this method can lead to an overcooked exterior and an unevenly cooked interior. We generally cook roast beef at temperatures between 250 and 350 degrees, depending on the meat's size and shape.