The flu vaccine that VaxPro administers is made with inactivated virus, therefore by itself it can not make you sick. In fact, that is an old wife’s tale. However, some people do experience side-effects such as muscle aches, headaches and low-grade fever. Some people do get the flu around the time of their annual flu shot. But that is mere coincidence and they were probably infected with influenza before they received their flu shot. It takes two weeks for the average person to build substantial immunity to influenza. Therefore, VaxPro advises that people, especially seniors and high-risk patients, receive their flu shot vaccination as early as possible, preferably in mid-September.