1. Infectious Diseases

2. Infectious Disease Aka Communicable Diseases Caused by micro-organisms
Parasite – lives in/on and feeds on host

3. Pathogens Pathogens Bacteria Virus Fungi Micro-organisms
Enter the body
Multiply
Cause disease
Bacteria
Virus
Fungi

4. Bacteria Single-cell micro-organisms Release toxins Examples
Food poisoning –bacteria in food
Tetanus – bacteria on objects/soil
Staph

5. Virus Smallest parasite Enter cells and take over Multiply
Cause colds/ flu
HIV

6. Fungi Not all are harmful Some cause rashes
Mushroom/ yeast/ mold/ fungi
Some cause rashes
Ringworm & athlete’s foot

7. Spreading Infectious Disease
Physical contact w/ infected person
Contact w/ contaminated object
Environmental sources
Contact w/ contaminated animals

8. Contaminated Animals Animal bites *Eating bad food*
Rabies/ Malaria/ Bird flu
HIV/ AIDS

9. Contaminated Object Most infections die quickly when exposed to air
Some can live on objects
Lice

10. Contact w/ Contaminated Person
Skin to skin contact
Sneeze/ cough
Cold/ STI/ flu/ chicken pox

11. Environmental Sources
Food/ water/ soil
Lead poisoning/ food poisoning
Fungi/ mold/ pathogens in water
Old food left out
Contaminated animals

12. Stages of Disease Exposure Incubation Period Prodromal Period
Acute Stage
Recovery Stage
Convalescence
Immunity

13. Exposure & Incubation Exposure = contact
Incubation = growth/ maturation
No signs/ symptoms
Pathogen/ parasite grows and multiplies

14. Prodromal Stage Slight signs & symptoms Ex: achy/ sore/ tired
Contagious!

15. Acute Stage
Severe symptoms
Most contagious
Most affected

16. Recovery Stage Signs/ symptoms begin to decrease
Temperature is reduced
Feeling better

17. Covalescence Infection is gone Still not quite 100% Can relapse
Need rest, sleep, healthy diet, antibiotics

18. Immunity
Feel 100%
Body has antibodies
Cannot catch same infection

19. Questions?