Vaccines are a number of drugs used as a preventive measure for diseases and allergies. When germs enter our body, the immune system recognises them as foreign substances (antigens agents); therefore, the system itself is responsible for putting the production of the required amount of antibodies up to combat these antigens. Based on this process, the vaccines contain weakened or killed antigens that stimulate the immune system to produce antibodies. That way, the body is ready to fight germs or viruses for which you have been vaccinated. In the infant stage an immunisation schedule for common diseases (and even some already eradicated in some parts of the world) is planned and every age is assigned the corresponding vaccines. For adults, a series of seasonal vaccines (such as flu, for example) and a number of compulsory vaccinations before travelling to certain countries in other continents that may involve the risk of transmission of diseases of these areas are established.