Diphtheria is a disease of bacterial origin, mainly affecting the upper respiratory tract, causing symptoms such as pharyngitis and laryngitis, leading to death in severe cases. In tropical countries, it also appears in a cutaneous form, which causes ulcers.

The vaccine is the best tool to protect against a disease that used to be a leading cause of infant mortality, with lethality rates of 5-10% and up to 20% in children under 5 and adults over 40.

The Italian National Vaccination Plan calls for the administration of 3 doses at 3, 5 and 11 months of age, with a first booster dose at 6 years of age that is an integral part of primary immunisation. This is followed by boosters every 10 years.

The vaccine is composed of purified diphtheria anatoxin and is administered intramuscularly. In Italy it is in conjugate form with the tetanus vaccine.