GOVERNMENT HEALTH CARE: How Did School Staffers Get Insulin Instead of Flu Vaccine? “While ABC News contacted people at the departments of health for the town of Wellesley and the Commonwealth of Massachusetts, as well as the Wellesley School District, it remains unclear how the flu vaccine, which is distributed in pre-filled syringes, was mistaken for insulin, which is drawn from a vial because each dose needs to be calibrated when it is given.”