Children were much more likely to catch measles if they weren't vaccinated. Children are commonly paralyzed by polio in India or killed by diphtheria in Russia. Because the United States has a high rate of tourist, immigrant, and international business travel, outbreaks of these diseases are only a plane ride away. Because vaccines are given to people who are not sick, they are held to the highest standards of safety. As a result, they are among the safest things we put into our bodies.
All vaccines have possible side effects.
Most side effects are mild, such as pain or tenderness where the shot is given. But some side effects of vaccines can be severe. For example, vaccines, like all medicines, have been found to rarely cause a severe allergic reaction called anaphylaxis. Symptoms of anaphylaxis can occur within 15 minutes of getting any vaccine and include hives, difficulty breathing, and low blood pressure. Although the reaction can be treated, it can also be quite frightening.