vaccination and variolation

Question 1

what are the two reasons that you are only infected with a pathogen once

Answer 1

lack of persistence - for some reason, the pathogen is removed from the environment
immunity - infected individuals become resistant to the infection

Question 2

what is variolation

Answer 2

using a small controlled amount of infectious agent to induce infection and immunity

Question 3

what infection are you immune to if you have had cow pox

Answer 3

small pox

Question 4

which is more controlled - vaccination or variolation

Answer 4

vaccination

Question 5

what is attenuation

Answer 5

methods to prepare weakened versions of infectious agents (vaccines)

Question 6

how is a virus attenuated

Answer 6

virus is isolated and cultured on a host (human cells)
the virus is incubated on cells from another host (monkey)
virus spontaneously mutates and grows on monkey cells
the virus can be used as a vaccine as it can’t grow on human cells

Question 7

what are killed vaccines

Answer 7

use chemicals or heat to kill the organism an render it uninfective
(the antigens from the killed organisms can still induce immunity)

Question 8

what are subunit vaccines

Answer 8

isolate antigens from cultivated pathogen
antibodies to antigens can protect against infection
(only exposed to part of the virus)

Question 9

what are the 3 ways a vaccine can be produced

Answer 9

attenuated - make attenuated pathogen using culture methods
killed - kill the pathogen
subunit - kill the pathogen and isolate its protective antigens

Question 10

give an example of an attenuated virus

Answer 10

MMR

Question 11

give an example of a killed virus

Answer 11

Inactivated polio (salk)

Question 12

give an example of a subunit vaccine

Answer 12

DTP

Question 13

what is herd immunity

Answer 13

indirect protection from infectious disease that occurs when a large percentage of a population has become immune to an infection, providing a measure of protection for individuals who are not immune

Question 14

what are the disease causing parts of pathogens called

Answer 14

toxins

Question 15

how do vaccines protect from infection

Answer 15

they induce immunological memory so that if you are naturally exposed to the pathogen your immune response will be stronger

Question 16

what are the 5 phases of adaptive immune responses

Answer 16

antigen recognition
lymphocyte activation 
antigen elimination
contraction (homeostasis)
memory