Patients with vaccine will not get sick when exposed to the flu virus compared to a person who did not receive the flu shot. A controlled number of patients will need to be vaccinated first before exposing all participants to the flu virus. With that, the following are the parameters of the experiment: independent variable of this experiment would be the days of patient monitoring; the dependent variable is the number of people getting sick; and control of the experiment would be the infected patients without the flu shot.