Understanding how vaccines work
This fact sheet provides an in-depth summary of how the body fights infection and how vaccines activate the body’s natural defenses to produce immunity. The document covers how vaccines work, the various types of vaccines, and explains why vaccines can require more than one dose to be fully effective.
More Resources
Expand your knowledge using our growing database of resources on vaccines and immunization.

Online Training
Learn vaccine safety basics
This site provides an e-learning course developed by the WHO regarding vaccine safety basics for health workers. The course covers vaccines…
Article
Studies show vaccines are safe and effective
This site lists vaccine safety studies and the supporting data that show them to be safe and effective to prevent serious disease. This article…

Article
Vaccine safety FAQ
This document covers frequently asked questions regarding vaccine safety. The information addresses several of the most common concerns about vaccine…

Article
Immunization data and statistics
This site is a resource for data on vaccine-preventable diseases and immunization rates. It provides a wide cross section of reports on the impact…