
Vaccines and immunization: What is vaccination?
Oct 22, 2025 · The vaccine is therefore a safe and clever way to produce an immune response in the body, without causing illness. Our immune systems are designed to remember. Once exposed to …
COVID-19 vaccines - World Health Organization (WHO)
The COVID-19 global health emergency saw the fastest vaccine rollout the world has ever seen. Now it’s time to share just how remarkable that journey really was. The Delivery is a tool that allows you to …
How do vaccines work? - World Health Organization (WHO)
Feb 25, 2025 · This article is part of a series of explainers on vaccine development and distribution. Learn more about vaccines – from how they work and how they’re made to ensuring safety and …
What's in a vaccine? - World Health Organization (WHO)
Sep 4, 2025 · Live-attenuated vaccine A live-attenuated vaccine uses a living but weakened version of the virus or one that’s very similar. The measles, mumps and rubella (MMR) vaccine and the …
Explainers - World Health Organization (WHO)
Feb 25, 2025 · Vaccine explainers "Vaccines Explained" is a series of illustrated articles that describe how vaccines work, how they’re developed and distributed and how their safety is carefully …
Vaccines and immunization: Vaccine safety
Jul 15, 2025 · Together with governments, vaccine manufacturers, scientists and medical experts, WHO's vaccine safety programme is constantly helping monitor the safety of vaccines. This helps …
Know the facts - World Health Organization (WHO)
Mar 20, 2020 · Vaccination is a simple, safe, and effective way of protecting people against harmful diseases, before they come into contact with them. It uses your body’s natural defences to build …
Types of data requested to inform May 2025 COVID-19 vaccine antigen ...
Mar 25, 2025 · The WHO Technical Advisory Group on COVID-19 Vaccine Composition (TAG-CO-VAC) continues to closely monitor the genetic and antigenic evolution of SARS-CoV-2 variants, immune …
Coronavirus disease (COVID-19): Vaccines and vaccine safety
Oct 8, 2024 · This page answers the most frequently asked questions about COVID-19 vaccines and vaccine safety. If the information you are looking for is not here, check out our related links on the …
Statement on the antigen composition of COVID-19 vaccines
May 15, 2025 · The TAG-CO-VAC reconvened on 6-7 May 2025 to review the genetic and antigenic evolution of SARS-CoV-2; immune responses to SARS-CoV-2 infection and/or COVID-19 …