Welcome back Mr. Andersen who explains how DNA and RNA viruses replicate in host cells. He also describes the lytic and lysogenic cycles. A 10:30 minute YouTube video.

A 5:14 minute animation of the HIV virus replicating in a T cell from medical animator, Dr. Rufu Rajadurai.

Dr. Susan Lindquist explains how prion diseases, like mad cow disease, arise and spread in this 4:21 minute YouTube video from iBioseminars.

An analysis of raw sewage reveals more unknown viruses, than previously identified ones. That's scary. A 2011 article from ScienceDaily.com

Coral reefs may be threatened by viruses that infect microalgae that have a symbiotic relationship with coral. A 2012 article from ScienceDaily.com

A study in Yellowstone Park suggests that viruses travel from one pool to another through steam. A 2007 article from ScienceDaily.com