Haemophilus influenzae type b (Hib) is an obligate human pathogen and an important cause of invasive bacterial infections in both children and adults, with the highest incidence among young children.
HIV is a virus which attacks the immune system and causes a lifelong severe illness with a long incubation period. The end-stage of the infection, acquired immunodeficiency syndrome (AIDS), results from the destruction of the immune system.
Rabies is a disease caused by rabies virus (a Lyssavirus). Every year, a small number of cases of rabies is reported in Europe - travel-related or autochthonous.
Severe acute respiratory syndrome (SARS) is a life-threatening respiratory disease caused by a recently identified coronavirus; the SARS-associated coronavirus (SARS-CoV). This is believed to be an animal virus that recently crossed the species barrier to infect humans.