Transcript Microlife Infectious Diseases

Virus: Microlife
Infectious Diseases
Objective: you will be able to
understand and explain how viruses
attack and effect human cells
Intro: Infectious Disease Terms
Asian Bird Flu 2007
Disease which travels
easily from one organism
to another: Can also
travel between species as
well
Pandemic – fast
spreading international
outbreak
Epidemic- wide spread
out break of disease at a
specific location
Pathogen
Pathogen- Any organism that
causes diseases
Carrier- any human giving a
disease to another human
Vector- any NON-HUMAN
source of a disease being
passed on to a human
Diseases are primarily
responsible for damaging
individual cells, which causes
us “sickness” symptoms” as
cells break down
Ex: sore throat
4 Forms of Pathogens
Virus
Bacteria
Fungi
Protists
Bacteria
What are Viruses?
Viruses
HIV Virus
Non- Living: Do not
require any energy to
survive; No food/gas
needs
Extremely Small
Organism made up of
DNA or RNA and a
Protein Coat
Only capable of
reproducing itself by “hijacking” another cell
3 Main forms of Viruses
(Norovirus) /Polyhedral
Bacteriophage
(Filovirus)/ Rod Shaped )
All viruses have two types of
infection cycles
Lytic Cycle (Active)
show signs of
sickness immediately
Lysogenic Cycle (Non
Active) no illness
creates “provirus
cells” within body then
becomes active
Lysogenic Cycle
Shows no disease
symptoms, may carry
virus for years
FACT: HIV can stay like
this for over 10 YEARS!!
1. Virus attaches to host
2. Viral DNA integrates
or combines with cells
DNA; becomes a
“provirus” cell
3. As cell splits and
divides virus replicates
with cell creating more
“provirus” cells
4. Some trigger activates
virus: become ill
Lytic Cycle
Show disease symptoms
Virus actively attacking cells
1. Virus attaches to host cell
2. Virus enters host cell
3. Virus destroys host cell’s
DNA, replaces DNA with its
own VIRAL DNA
4. “Hijacked” cell creates more
Viral DNA and protein coating
5. Lysis-host cell ruptures and
releases hundreds of new
virus to attack more cells
Common Viruses
Chicken pox
Herpes
HIV
Ebola
Epstein Bar (mono)
Mumps
Warts
Influenza
Hepatitis
Common Cold
How we fight back: Vaccines