chapter 20 epidemiology
Download
Skip this Video
Download Presentation
Chapter 20: Epidemiology

Loading in 2 Seconds...

play fullscreen
1 / 56

Epidemiology - PowerPoint PPT Presentation


  • 181 Views
  • Uploaded on

Chapter 20: Epidemiology. Important Point:. If you are having trouble understanding lecture material: Try reading your text before attending lectures. And take the time to read it well!. Common Terms. Common Terms. Fraction that get sick!.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Epidemiology' - benjamin


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
important point
Important Point:

If you are having trouble

understanding lecture material:

Try reading your text

before attending lectures.

And take the time to read it well!

common terms4
Common Terms

Fraction that get sick!

common source outbreak10

The Broad Street Pump.

Common-Source Outbreak

Individual cases of (deaths from) cholera.

common source outbreak11
Common-Source Outbreak

Sewage contamination of drinking water.

propagating epidemic
Propagating Epidemic

Epidemic spreads via multiple sources.

pandemic
Pandemic

Index case.

direct fecal oral transmission
Direct Fecal-Oral Transmission

Giardiasis in daycare centers.

indirect contact transmission
Indirect-Contact Transmission

Methicillin-resistant Staphylococcus aurius (MRSA)?

Beddings are an example of a Fomite, an inanimate object that can transmit pathogens between people.

indirect contact transmission22
Indirect-Contact Transmission

Influenza virus?

Door knobs are another good example of a fomite.

droplet transmission
Droplet Transmission

Less than

one meter

Measles?

airborne transmission
Airborne Transmission

More than

one meter

Mycobacterium tuberculosis?

airborne transmission25
Airborne Transmission

Contact with air from small room containing 12 people.

Contact with air from clean, empty room.

waterborne transmission
Waterborne Transmission

Cryptosporidium parvum?

waterborne transmission27
Waterborne Transmission

Giardiasis from water.

foodborne transmission29
Foodborne Transmission

Balantidium coli

portals of entry31
Portals of Entry

“Many organisms that cause one disease if they enter one body site are harmless if they enter another, e.g., various enteric urinary-tract pathogens.

epidemiology

...is pretty crappy at dealing with cause and effect when associations are subtle.

Epidemiology

Do power lines really cause cancer?

What about cell phones?

epidemiology33

...is pretty crappy at dealing with cause and effect when associations are subtle. However...

Epidemiology

What about smoking, a crappy diet, and couch-potato tendencies?

types of epidemiologcal studies

Descriptive studies are simply those that describe the events and rates of disease. They tend to be the first sets of studies done.Quoted or paraphrased from http://dante.med.utoronto.ca/doch/Year1/EPIModule/Part6a.htm

  • Observational/Analytical studies then look towards finding out the causes of the observed rates. They are called "observational" since the epidemiologist does not intervene in the assignment of exposure.
  • Experimental studies are formal research experiments. The classic example is the randomized control trial where one group is randomly assigned a treatment and a control group gets the placebo or "usual" treatment.
  • Experimental studies are expensive and test a very specific question. Usually a great deal of descriptive and observational studies are done first.
Types of Epidemiologcal Studies
nosocomial infections
Nosocomial Infections

2 million acquire and 20,000 die, per-year in the U.S., from nosocomial Infections.

Nosocomial Infections are, by definition, hospital or clinically acquired.

ad