Vaccinations have accounted for a decrease in the number of annual cases of many diseases within the United States, such as diphtheria, influenza, measles, mumps, rubella, and hepatitis A and B. Many children in the U.S. receive recommended vaccinations when they reach certain ages and many states require such vaccinations before children are allowed to enter public schools. In 2017, around 91.5 percent of all children aged 19 to 35 months had been vaccinated against measles, mumps and rubella.
In most cases, vaccines have no side effects; however, like any medication certain unwanted effects may occur. In the United States, such complaints are filed under the National Vaccine Injury Compensation Program (VICP). From 1988 to early 2019, 691 petitions were filed with the VICP seeking compensation for injuries caused by the hepatitis B vaccine; however compensation was awarded in only 272 cases.
Such incidences result in a small minority of people refusing vaccinations for their children. Vaccine hesitancy, or vaccine refusal has increased in many parts of the world in recent years. In the United States, a rise in vaccine refusal has lead to an increased number of measles outbreaks. This problem has become so serious that in 2019, the World Health Organization (WHO) listed vaccine hesitancy among the top ten threats to global health that year.