Nucleic acid (double or single stranded DNA or RNA)
Protein coat (capsid)
Help virus attack host
Generalized (cd: Activity)
Can only infect cells in its host range
Protein coat recognition (lock and key fit)
Insert nucleic acid in cell
Reprogram cell to produce virus particles
Emerge from cell
Lytic cycle (cd: Activity)
Lysogenic cycle (cd: Activity)
Transmission in Plants
West Nile Encephalitis
Inflammation of the brain
Commonly found in Africa, E. Europe, W. Asia, Middle East
New to W. Hemisphere in 1999
83 cases reported in 1999, 2000 - all in New York City metro area
9 deaths in 1999, 2000
2001- first cases outside NYC area
Will you contract West Nile virus?
Human Immunodeficiency Virus (HIV)
Reproductive cycle of HIV (cd: Activity)
What about Bird Flu (Avian Influenza)?
Does Bird Flu Spread Easily to Humans?
Countries with human cases
East Asia and Pacific (Cambodia, China Indonesia, Thailand Vietnam)
Europe and Eurasia (Turkey)
Near East (Iraq)
Why the Concern?!
Potential for pandemic
Conditions for start of pandemic:
Viral Changes Enhancing Human-Human Transmission
Not really new, result from:
Mutations of existing viruses
Spread from one host type to another (expanded host range)
Hanta virus: mouse - human from dust/feces
Dissemination of virus from isolated populations to others:
World travel, etc.
CDC - Centers for Disease Control
In Atlanta, clearinghouse for disease info.
That's It For Viruses!!!!