Why do we need vaccines?

Some bacteria and viruses can make you very ill very quickly. The body does not have enough time to destroy the invaders before it is overwhelmed. Without vaccines, diseases such as diphtheria, polio and smallpox would still kill or disable many people. Worldwide vaccination programs have now wiped out smallpox completely. The only smallpox virus that exists is kept under tight security, deep frozen, in two laboratories in the USA and Russia. Whether or not these stocks should be destroyed is a very controversial subject.

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The English doctor Edward Jenner carried out the first vaccination against smallpox in 1796.

How do vaccines work?

A vaccine fools your body's immune system. You are injected with a harmless version of the bacterium or virus that usually causes the illness: it is either dead, or modified - attenuated - so that it cannot attack your body. But your defender cells still learn what it looks like. If you ever encounter the real thing, they will remember, and respond immediately to destroy it.

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Vaccines contain harmless versions of bacteria and viruses.


Principal Funder:

Wellcome trust

Major Sponsors:

GlaxoSmithKline life technologies