Transcript Chapter 3 Part 3

Chapter 32
Epidemiology
the Core
Understanding of
Public Health
Epidemiology: Study of Disease Occurrence,
Distribution and Determinants of Health
Infectious Disease Death Rates, USA
Clicker Questions:
Clicker Questions:
Epidemic vs Endemic … Dots on A Map
John Snow – First Epidemiologist
Cholera Outbreak,
London 1854
The Pump, The Pub
Epidemiology
Who, When Where…Tracking Disease Pattern
Prevalence = (Total # cases in a pop)/Total people x 100%
Incidence = (# New Cases)/(# Susceptible People)
Usually based on 100,000 people
Centers for Disease Control, Atlanta
Morbidity and Mortality Weekly Report
Morbidity and Mortality Weekly Report
Clinical Stages of Disease
Classical Symptoms Here
Incubation Periods
Some diseases are transmitted by active carriers: a
pathogen infected individual who has had the disease and
recovered, but continues to carry and spread the pathogen
Incidence of California Encephalitis
Clicker Question:
Types of Epidemics by Incidence
Co-Evolution of Host/Pathogen:
The Australian Rabbit and Myxoma Virus Experiment
Clicker Question:
Herd Immunity
The USA AIDS Eipdemic
HIV Infects Both Sexes
Nosocomial Infections
Causes of Death: Africa and Americas
Clicker Question
Emerging and Re-emerging Infectious Diseases
Small Pox: The Eradicated Disease?
Clicker Question:
Small Pox: The Eradicated Disease?
Clicker Question Follow Up:
Planned Bioterrorist Attacks
1984: A group sprayed salad bars in The Dalles, Oregon with
Salmonella enterica Tiphimuriuim causing 751 salmonellosis
cases.
1995: Sarin (neurotoxic gas) sprayed in Tokyo subway, killed
several people.
Since 1995: Most common are Bacillus anthracis spores:
sprays, in letters, etc.
Bacillus anthracis causes Anthrax
Clicker Question:
Bacillus anthracis causes Anthrax
Clicker Question:
The Three Forms of
Anthrax
1. Cutaneous Anthrax (skin
hemorrhage)
2. Pulmonary Anthrax
(lung and cerebral
hemorrhage; fatality
rates at ~90% plus)
Cutaneous Anthrax
3. Gastrointestinal Anthrax
(rare)
Pulmonary Anthrax
Anthrax: 2 Toxins, 3 Proteins
PA Protective Antigen
LF Lethal Factor
EF Edema Factor
_____________________________________________________
PA-LF Lethal Toxin (cytotoxin)
PA-EF Edema Toxin
Clicker Question:
Weaponized Anthrax Spores
Endospores mixed with talc powder: in mailed envelopes or
packages to news media (Florida), government (Washington DC),
non-focused in Pennsylvania, New Jersey, New York.
22 cases of Anthrax: 11 cutaneous + 11 pulmonary
5 Deaths
Bioterroist was a bioweapons lab worker.
Bioweapon facility in Sverdlovsk, Russia: inadvertant release of 1
gram of endospores  77 anthrax cases, 66 died.
Anthrax Vaccination - Treatment
Incubation Period: at least 8 days
1. treatment with Ciprofloxacin prophylactically to exposed
persons.
2. Vaccine: AVA Anthrax Vaccine Absorbed : prepared from
cell-free culture filtrate.
3. Clicker Question: