The last two centuries have seen an extraordinary reduction in the morbidity and mortality due to infectious
diseases as a result of improvements in health and hygiene-related conditions and the introduction of vaccinations. Vaccines
against infectious diseases with a human reservoir can have the following beneficial effects : control, elimination, eradication
and extinction of the disease. Vaccines have facilitated the eradication of smallpox in 1980 and a massive reduction
in cases of poliomyelitis, of which only 1,655 were recorded worldwide in 2008. The elimination of poliomyelitis in the
European region was certified by the WHO in 2002. The essential conditions for the elimination of communicable
diseases are political commitment, the implementation of vaccination programmes and exhaustive disease surveillance.