Vaccine Fast Facts

(CNN) Here's a look at information and statistics concerning vaccines in the United States.

Facts:

There are 14 different vaccines that are recommended for children between birth and age six, including those for diphtheria, pertussis, tetanus, influenza, measles, mumps and rubella.

For more than 100 years, there has been public discord regarding vaccines based on issues like individual rights, religious freedoms, distrust of government and the effects that vaccines may have on the health of children.

Exemptions to vaccines fall into three general categories: medical, religious and philosophical.

Median immunization coverage for state-required vaccines was approximately 94.3% for children entering kindergarten during the 2017-2018 school year, according to the Centers for Disease Control and Prevention (CDC).

As of July 2019, 45 states and the District of Columbia allow religious exemptions from vaccines, and 15 states allow philosophical (non-spiritual) exemptions.

Timeline:

1855 - Massachusetts mandates that school children are to be vaccinated (only the smallpox vaccine is available at the time).

February 20, 1905 - In Jacobson v. Massachusetts, the US Supreme Court upholds the State's right to compel immunizing against smallpox.

November 13, 1922 - The US Supreme Court denies any constitutional violation in Zucht v. Kingin which Rosalyn Zucht believes that requiring vaccines violates her right to liberty without due process. The High Court opines that city ordinances that require vaccinations for children to attend school are a "discretion required for the protection of the public health."

1952 - Dr. Jonas Salk and his team develop a vaccine for polio. A nationwide trial leads to the vaccine being declared in 1955 to be safe and effective.

1963 - The first measles vaccine is released.

1983 - A schedule for active immunizations is recommended by the CDC.

You will find the whole timeline here.