Chapter 19 Flashcards
A) What makes a disease contagious or communicable? Give some examples.
can be transmitted from one host to another, colds, measles, flu etc
1) How is disease transmission determined? How can they be controlled?
it is determined by the environment, the pathogen, and the host. ie sanitation prevents pathogen from acessing the host
B) What makes a disease non-communicable?
when it doens’t spread from host to host. ie. tetanus tat enters the host from environment, or normal flora
C) What is the attack rate? What does it reflect?
percentage of people who get ill after exposure to a certain pathogen. this reflect how many people exposed verses how many get ill.
D) What is the incidence of a disease?
number of new cases within a specific timme period
E) What is prevalence of a disease?
number of cases at any time within a certain time period. usuaslly given as a rate
F) What does the term morbidity refer to?
incidence of disease of a population at risk
G) What does the term mortality refer to?
overall death rate in a population
1) What is the case fatality rate? Which diseases have a high rate?
percentage of a population that dies of a specific disease. Ebola and aids
2) Why has the case-fatality rate for AIDS gone down while the prevalence has gone up?
treatment has improves, but prevalence has increased because more people are living with aids
H) What makes a disease endemic vs. sporadic?
endemic:constantly present in a population ie cold
Sporadic: cases occur only time to time
I) What constitutes an epidemic? [Figure 19.1]
large numbers of cases in a poplulation
1) Can a disease not normally present in an area cause an epidemic?
yes
J) What constitutes an outbreak?
cluster f cases occuring in a brief amount of time and effecting a specific poplulation
K) When does an epidemic turn into a pandemic?
when an epidemic spreads world wide
L) What is a reservoir of infection? [Figure 19.2]
natural habitat of a certain pathogen. can be inn animals, soil,and water
1) Why doesn’t the United States have epidemics of plague?
because they control their rodents such as mice
2) Can humans be reservoirs?
yes
3) Why can it be easier to contain symptomatic illnesses?
- Can they be spread before symptoms appear?
because people are aware there is an issue and can take prevenative measures.
yes they can spread before symptoms apear
4) What is problematic about asymptomatic carriers?
they do not know they are ill and do not take prevenative measures
5) What are some diseases spread by non-human reservoirs?
-
poultry: campylobacter, and samonella
rabies caused by skunks, and bats
y pestis by mice
What are zoonoses?
diseases that can be transmitted to humans, but can cause disease is
6) What are some organisms that have environmental reservoirs?
tetanus, botulism
M) What is a portal of exit and what’s it used for? Give an example.
route in which it leaves its resivor to be transmitted. ie through feces
N) What is a portal of entry and what’s it used for? Give an example. [Figure 19.3]
how it enters the body to infect it. it through cut, or mouth
O) What is horizontal transmission? [Figure 19.4]
transimission of pathogen fro one person to the other, via air, water, skin, or insect
1) What types of direct contact aid horizontal transmission?
hand shake, sex,
-How can direct contact transmission be avoided?
washing hands, using condoms etc.
2) How does indirect contact occur? How can you control transmission through this?
This is through passing via inadimate objects. (fomites) . You can do this by cleaning the environment.
3) How does droplet transmission occur? How can this be minimized?
3 feet within a person just breathing droplets in the air can get to you. this can be prevented via masks and keeping beds and desks 3 feet apart
4) How can pathogens be transmitted through food and water? How can this be minimized?
food: ie samonella in chickens tract as it lays and egg, or people preparing do not wash hands. Fecal matter in water that is not properly treated