Smallpox was a systemic disease, officially eradicated since 1979 (WHO), caused by infection with the Variola major virus, whose only reservoir was infected humans.
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.
Listeriosis is a disease caused by Listeria monocytogenes. The disease primarily causes problems in pregnant women, newborns, and adults with a weakened immune system.
Cholera is an acute diarrhoeal infection caused by the bacterium Vibrio cholera of serogroups O1 or O139. Humans are the only relevant reservoir, even though Vibrios can survive for a long time in coastal waters contaminated by human excreta.