Infectious Disease Flashcards
What are Pathogens?
They are Bacteria, Viruses, Parasites, and Fungi that cause disease by disrupting vital body processes or stimulating the immune system to mount a defense reaction
Stages of a Pathogen Infection
Incubation - exposed to Pathogen (non-contagious)
Prodromal - have symptoms and are contagious
Acute - Highest level of pathogen. most risk for spreading disease
Decline - At highest level for relapse
Recovery - Feeling good
Immunity
Immune Response
- Scavenger cells, such as neutophils arrive on site but only survive a few days.
- Macrophages engulf foreign matter and signal other immune cells, such as T cells to attack invaders
- Macrophages display antigens derived from digestion of ingested invaders. these activate T helper cells
- T helper cells multiply and activate B cells
- B cells divide and form plasma cells, which produce antibodies.
- Antibodies bind to invaders either destroying them or making them easier to destroy for macrophages.
- T suppressor cells monitor antibody producation and turn down plasma cells as infection starts to subside,
- Killer T cells form from T cytotoxic cells and then destroy infected cells.
Endemic
Happens to certain groups
Epidemic
Happens alot in certain area
Pandemic
Crosses continents (ebola)
Stages of the Reproducing Virus
- the virus attaches to the host and injects its genome in the cell
- The viral genome uses the host to replicate again and again
- Each new copy directs the cell to make it a protein shell
- The new viruses emerge and kill the host cell
Hep B spread through……
Unprotected sex, sharing needles, needlesticks or SHARPS exposure.
Infection and Death rate of health care workers from Hep B
8700 health care workers infected each year
200 a year die. ( is that workers or total population?)
Hep B Prevention
Good hygiene
Avoid high risk behaviors
Avoid contact with blood and contaminated surfaces
Vaccination: 3 doses given over 6 months. 96% develop immunity after 3rd dose
Hep C Demograpics
Most common bloodborne infection in US
Acute and chronic form of liver disease
leading indication for liver transplant
3% die from cirrhosis
Hep C symptoms
Muscle/joint pain
Jaundice
Mild abdominal pain (upper right quadrant (Liver))
loss of appetite
nausea
Fatigue
Dark Urine
Hep C spreads though…..
Spread by contact with blood of infected person
Sharing needles of syringes
sharing personal items
tattoo / piercing
there is no vaccine for Hep C
HIV Demographics
Retro virus that combines with host cell
may infect cells of immune system
(T cells, B cells, macrophages)
34 million pple world wide living with HIV
1,9 milliion deaths
HIV signs and symptoms
Fatigue
Weight loss
Muscle/joint pain
painful / swollen glands
night sweats
fever
