Public Health refers to conditions that influence population health. Therefore it is the only area of health that is not aimed at individual health, but to collective health. Its commitment is not to cure or to look after people affected by a certain illnesses, but to prevent risks affecting health of population as a whole and to promote healthy habits. This is why Public Health is a discipline that has been encouraged by public institutions over the years.

Public Health policies have logically an integrated perspective because, apart from health issues, such as vaccines, must observe economic, social and even urban issues. For instance, without potable water or sewerage networks population vulnerability to epidemiology would be enormous. In our context, we must have accurate information and monitoring mechanisms to detect and tackle infectious diseases such as flu or legionellosis only to mention the best known.

Epidemiologic surveillance constitutes the origin of Public Health policies in Catalonia , which can be traced up to the 14th century, when the Consell de Cent ( Barcelona' s medieval Town Council), asked doctor Ramon de Teserach for advice on the measures to take to monitor epidemics in the city.