Exam 1 Lecture 6 Flashcards
Who is known for being the father of modern epidemiology?
John Snow
What was the pathogen that caused a major outbreak in the 1800s within London?
Cholera
How does cholera spread?
Through contaminated food or water
What is the miasma theory?
Disease is caused by pollution or “bad air”
What did Dr. Snow believe the cause of the cholera outbreak was?
Sewage being dumped into the river (no modern toilets/running water in homes)
Epidemiology is driven by ____. It relies on a systematic and unbiased approach to the collection, analysis, and interpretation of data.
Data
What are the 3 factors involved in the epidemiological triad?
environment, host, agent
What is the agent?
disease producing microorganism
What are important characteristics of an agent?
- virulence, dose, toxicity
- survival in various environments
- antibiotic susceptibility
Who is the host?
human or animal who can get the disease
What are important characteristics of the host?
- behavior (age, sex, sexual practices, hygiene)
- host genetics
- immunological status (Vaccination)
- disease history
What is the environment?
factors that affect the agent or opportunity for exposure
What are important characteristics of the environment?
- place (climate, geology)
- presence of insects that can act as vectors
- socioeconomics (crowding, sanitation, healthcare access)
What is a reservoir?
environment in which the pathogen usually lives, grows, and multiplies
List 3 reservoirs
humans
environment
animals
True or false: the reservoir may or may not be the source from which an agent is transferred to a host
true
True or false: Asymptomatic carriers are more likely to transmit the disease in comparison to symptomatic carriers, who take precautions to reduce transmission
True
Name 2 examples of a water-borne illness
Cholera, legionella
Name an example of a soil-borne illness
histoplasma
Name 3 types of direct contact transmission
Vertical (mom to child), horizontal (direct contact, e.g. sex), droplet/airborne spread
Name 2 types of indirect transmission
Vehicle transmission (water, food), vector transmission (mosquito)
What is the R-naught value?
reproduction number “how many people can an infected person spread the disease to”
name 3 factors that go into calculating R-naught
- infectious period: how long are they contagious?
- mode of transmission: how contagious is it?
- contact rate
True or False: Airborne infections spread faster than those that require physical contact, and thus have a lower R-naught
false - higher R-naught
True or False: When a disease infects people for a long period of time, the R-naught value typically increases
true
how is listeria usually spread?
eating contaminated food
how can listeria be killed?
cooking food properly
what is the definition of an outbreak?
an outbreak occurs when the observed amount of cases of the disease is higher than you would expect at that particular time/place
define incidence
number of NEW cases of a disease that develop in a population at a given time
define prevalence
number of existing cases of a disease in a population at a given time
__________ conditions are conditions that need to be reported to public health
notifiable
define a pandemic
widespread globally
define epidemic
sudden increase in cases of a disease but limited to a certain population
define endemic
present in a population at a constant/low level
______ is considered a gold standard and is used to generate a DNA fingerprint
PGFE
True or False: DNA relatedness is not sufficient to establish a link, you need epidemiological connections
True
What is PulseNet?
national & international lab network that connects foodborne illness to detect outbreaks
