Vaccines are used worldwide as a highly effective way to protect people from contracting infectious diseases. They also help to prevent the spread of diseases in the community. Vaccines work by ‘teaching’ a person's immune system (the body’s natural defences) to defend itself against a specific disease. They mainly target diseases caused by viruses or bacteria.
The first vaccine was developed in the 18th century in the United Kingdom. It was a vaccine against smallpox, a deadly disease. Smallpox is now eradicated worldwide in humans thanks to vaccination. The last known naturally occurring case was recorded in 1977 in Somalia.
Nowadays, there are vaccines for many diseases. Research is ongoing to develop vaccines against more diseases. A vaccine was developed against Ebola virus disease and research is underway on vaccines to protect against human immunodeficiency virus (HIV).
Safety, quality and standards
Before any new vaccine can be used, it has to undergo rigorous testing. The vaccine can only be approved for use in the European Union (EU) and European Economic Area (EEA) after a scientific evaluation of the results of these tests to ensure its quality, safety and effectiveness.
This evaluation needs to show that a vaccine’s benefits in protecting people against diseases are far greater than any potential risk. The scientific experts evaluating vaccines always consider the benefits and any potential risks very carefully, in particular because vaccines are given to healthy people.
Only then, after approval, can a vaccine be manufactured, marketed and used to protect people. The vaccine is continuously monitored to ensure it remains safe and effective.
As with any medicine, some people may experience side effects from a vaccine, but these are usually mild and short-lived. They can include mild fever, or pain or redness at the injection site. Serious side effects are very rare.
Benefits of vaccinating
Vaccines prevent diseases that could cause health problems, disabilities, or death. Many diseases are now rare due to vaccination.
Approval of vaccines in the European Union
Information on vaccine approval, testing, and scientific evaluation by authorities, in order to control quality, effectiveness and safety.
Monitoring vaccine safety and reporting side effects
After vaccines are approved, EU and national authorities continually monitor side effects in people who have taken the vaccine.
Approved vaccines are effective at preventing disease, serious symptoms, and decreasing transmission.
How vaccines work
Find out how vaccines protect people by triggering an immune response.
Decisions on vaccines in use in different European countries
Learn how European countries decide on which vaccines will be part of their national vaccination programmes.