Spore

In biology, a spore is any object by which a living organism uses for reproduction that has adapted for wide dispersal, survival in adverse conditions, or both. 
In medicine, several transmissible diseases can either be spread from patient to patient by spores, allow the organism to reproduce within a host, or allow the pathogen to protect itself from the body's normal immune response.
Although a fungus usually spreads by branching from an existing system, most species are also capable of producing spores which can be dispersed on the wind.
Certain types of bacteria can form spores in adverse conditions, allowing them to survive until conditions are better and they can continue reproducing. 
Spore at WikipediaCategory:Infection