1. Disease Transmission
Deer mouse
(spreads hantavirus)

2. Epidemiology
Study of disease origin (where it started), cause (what organism), and transmission (how it spreads).
Incubation period: the period of time that elapses from the infection of the host to the appearance of symptoms.
Virulence: ability of a pathogen to cause disease

3. Epidemiology (cont.)
Quarantine: enforced isolation of individuals that may have been exposed to a contagious or infectious disease.
Carrier: infected individual who is capable of spreading disease but shows no sign of disease.

4. Airborne Transmission
Aerosolized droplets that enter the body through the mouth, nose, or eyes.
Ex: Influenza

5. Direct Contact
Spread by direct physical contact with an infected individual, usually passed through blood or body fluids.
Ex: Ringworm, Mono

6. Fecal – Oral Transmission
Pathogens in fecal particles from one host are ingested by another host.
Ex: Hepatitis A (causes hepatitis outbreaks at restaurants)

7. Indirect Contact
Germs are able to survive on surfaces. When the surface is touched, the germs are transmitted to the body.
Ex: virus that causes the common cold

8. Vector – Borne Transmission
Disease is passed by animals such as ticks, mosquitoes, and rodents. Usually passed through biting or contact with feces.
Ex: Malaria, Lyme Disease