Many diseases are caused by viruses or bacteria, which may be considered introduced species under certain circumstances (although viruses are not truly living organisms and need another organism as a host). Describe the following exotic diseases and explain their origins.
Smallpox
Chestnut blight

Question

Many diseases are caused by viruses or bacteria, which may be considered introduced species under certain circumstances (although viruses are not truly living organisms and need another organism as a host). Describe the following exotic diseases and explain their origins. 
    Smallpox
    Chestnut blight

shrutipande9 · Answer

http://www.who.int/csr/disease/smallpox/en/ http://www.esf.edu/chestnut/background.htm

shreehari499 · Answer

Yeah..explaining the whole thing will be very long!

anonymous · Answer

Oh yeah, what a mess.  I would say go to wikipedia and read those. Make sure you look to see if the citations are reliable.