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.
When you are ready to roast the beef, preheat the oven to 250 degrees F. If your roast has a thick fat layer, score it in a criss-cross pattern. Season the roast with salt and pepper, and rub it in with your hands. Finish the roast off with a coating of vegetable oil, and rub that in as well.. Once you have finished prepping the roast and the oven is up to heat, turn the oven down to 200 degrees F and put the roast in. If you have a thermometer that can be in the roast while it is in the oven, put that in the very center of the roast. You will let the roast cook until it reaches 118 degrees F.