Uploaded April 2025 | Updated September 2026, 3 weeks ago

---

Worried about diphtheria? No? Thank vaccines.

Learn more about Dr. Paul Offit: paul-offit.com

~~~
#EncyclopaediaBritannica
Inspiring curiosity and the joy of learning since 1768.

Web: britannica.com
Facebook: facebook.com/Britannica
Twitter: twitter.com/Britannica
Instagram: instagram.com/Britannica