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Vaccine Mandates: A Timeline
References & Edit History Related Topics
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Vaccine coverage and exemptions among kindergarteners in the United States Smallpox vaccination Oral polio vaccine Close-up of a person's torso showing a widespread red, blotchy rash characteristic of measles, with hands pulling up a green shirt to expose the skin. BCG vaccine Three line graphs display the dramatic decline in reported cases of diphtheria, polio, and measles in the United States from 1920 to 2019, each showing a sharp drop after the introduction of their respective vaccines. Diphtheria cases fell after 1921, polio after 1955, and measles after 1963, illustrating the impact of mass vaccination programs. An inset highlights an increase in measles cases after 2010. COVID-19 vaccine Vaccines by the numbers U.S. federal and state vaccine guidelines

Vaccine Mandates: A Timeline: References & Edit History

Article Contributors

Primary Contributors

  • Kara Rogers
    Kara Rogers is the senior editor of biomedical sciences at Encyclopædia Britannica, where she oversees a range of content from medicine and genetics to microorganisms. She joined Britannica in 2006 and has been a member of the National Association of Science Writers since 2009.

Article History

Type Description Contributor Date
Added an interactive on U.S. federal and state vaccine guidelines. Sep 23, 2026
Added a map showing changes in vaccine exemption rates among U.S. kindergarteners. Sep 12, 2025
New article added. Sep 10, 2025
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