Something which spreads like bacterial infection.
Any of various rod-shaped, spore-forming aerobic bacteria in the genus Bacillus, some of which cause disease.
Any bacilliform (rod-shaped) bacterium.
Either of the two related viruses, human immunodeficiency virus 1 (HIV-1) and human immunodeficiency virus 2 (HIV-2) that progressively destroy the body's immune system and can potentially lead to AIDS.