The most effective way to prevent measles is by vaccinating young children. Measles is a highly contagious viral disease that spreads through the air when an infected person coughs or sneezes. Vaccination creates immunity in the body, which helps to protect against the virus. This means that if a person comes into contact with someone who has measles, they are less likely to become infected. Vaccination not only protects the individual who receives the vaccine, but also helps to prevent the spread of the disease within the community. Therefore, vaccinating young children is an important public health measure to prevent measles outbreaks.