Immunology Exam 1 Material with
Complete Solutions
What is an antigen? - ANSWER-pretty much anything that the immune system
recognizes as a or port of a pathogen
- could be a protein, polypeptide, sugar residue, etc
What is immunity? - ANSWER-a state of protection against foreign pathogens or
substances (antigens)
Tell me about the observations of immunity in history! - ANSWER-- Thucydides, an
ancient historian, wrote in 430 bc of a plague in Athens where those who had recovered
from the plague could safely nurse/help the currently ill
- showed that if you had already had the illness, you were able to be around people who
currently had that illness
- modern day example: if you've had chicken pox before when you were a kid, you now
will not get it anymore even if you're around people who have it
Can we generate immunity without inducing disease? - ANSWER-YES!!
via vaccination!
What do vaccines do? - ANSWER-Prepares the immune system to eradicate an
infectious agent before it causes disease
- classic examples:
--> SMALLPOX
--> RABIES
Tell me about smallpox! - ANSWER-- Edward Jenner noticed that milkmaids were
immune to smallpox
- his hypothesis: they were immune because they were exposed to a less severe cow
pox virus (that was similar to smallpox)
- so hypothesized that if he took some puss from a cowpox blister and injected into
humans, we could be granted immunity to smallpox
--> actually inoculated 8-year old boy with cowpox puss, and then a couple weeks later
exposed him to smallpox and IT WORKED! the boy was granted immunity against
smallpox because he was exposed to the less severe cowpox virus
Tell me about rabies! - ANSWER---> Louis Pasteur worked with attenuated (weakened)
strains of rabies virus
,---> young boy bitten by rabid dog and thought if give young boy some attenuated
(weakened) rabies virus cultures, he could stop rabies from infecting the boy and IT
WORKED!
- rabies virus weird example because can administer vaccine AFTER bitten by rabid
animal
- rabies virus infects the central nervous system, so it takes some time for the virus to
actually spread to the CNS past the blood brain barrier!
---> helped the boy gain immunity to the rabies infection before it reached the blood
brain barrier
What is Edward Jenner credited for? - ANSWER-Developing the vaccine for small pox
What did Louis Pasteur find? - ANSWER-- found that can attenuate pathogens and use
them as vaccines
What are the two ways to attenuate a pathogen to make it a vaccine? - ANSWER-1.
AGE a culture to create an attenuated strain of the bacteria
2. HEAT-TREAT a culture to attenuate it!
Tell me about attenuation as vaccination! - ANSWER-- injected chicken (fowl) with
cholera, which then died
- then injected aged culture of cholera bacterium into a healthy chicken, and it didn't die
- then took fresh culture of cholera bacterium and injected into old chicken which
already survived a prior injection of cholera, and chicken lived!
--> we now know that it was because the old chicken was exposed to the
ATTENUATED strain which provided it an immune response to prevent it from dying
from cholera
- positive control: then gave fresh culture of cholera and injected into normal healthy
chicken that were not exposed to any bacteria and it died
- then did the same thing with bacillus anthracis, the bacteria that causes anthrax, but
instead inoculated sheep with HEAT treated bacillus anthracis
What is attenuation? - ANSWER-reducing the virulence of a culture (reduce the ability
to cause an infection)
"Virulence is reduced." What does that mean? - ANSWER-the ability to cause an
infection is reduced
Tell me about vaccination is a worldwide enterprise! - ANSWER-- if there's two people
that are infected without vaccine in a population of healthy unvaccinated people, the
majority of the population will become infected
,- if there's two people that are infected without vaccine in a population with 6 people that
were immunized against the pathogen/had the illness already and recovered, the
majority of the population will be infected, but the 6 people will be immune to it (because
there's a large reservoir of people who are not immunized)
- if there's two people that are infected without vaccine in a population with the majority
of people that are immunized against the pathogen, herd immunity allows most people
in the population to be immune to be safe from the pathogen
--> HERD IMMUNITY: if you have a large population of immunized individuals, those
individuals protect the non-immunized individuals
Describe herd immunity. - ANSWER---> HERD IMMUNITY: if you have a large
population of immunized individuals, those individuals protect the non-immunized
individuals
- if there are very few hosts that are susceptible to a pathogen, that pathogen cannot
spread through that population
What are two cases where herd immunity and vaccinations are very much needed? -
ANSWER-- HOSPITALS: hospital staff (healthy individuals) are vaccinated to protect
those who are too vulnerable (too young or too old to get vaccinations)
- college campuses also require students to be vaccinated to prevent the spread of
infection through the population
What are the social benefits of herd immunity? - ANSWER-- protect those that are
unable to be vaccinated (children, elderly, and immunocompromised) from being
infected
- can lead to disease being eradicated
- if can prevent people from getting sick, can reduce healthcare costs
- can control spread of disease
What are the negatives associated with herd immunity? - ANSWER-- belief that
vaccines don't work and your body can find immunity on its own
- can lead to overpopulation
- we're forcing people to do something they may not want to do
What are the two ways that a susceptible population can become IMMUNE to a
pathogen? - ANSWER-1. INFECTED: become exposed to the infection
2. IMMUNIZED: become exposed to the vaccine
Tell me about the hope of herd immunity! - ANSWER-the hope is that there are enough
people that have gained immunity to the pathogen via being infected or immunized, in
order to protect the part of the population that is susceptible to the pathogen
If talking about the flu, need what immunization rates to have immunity? - ANSWER-70-
80% of population needs to be vaccinated to have herd immunity
, If talking about the measles, need what immunization rates to have immunity? -
ANSWER-need close to 100% immunization rate in order to have herd immunity!!
because extremely contagious and exists in airborne state for a long period of time
What are the 2 things that the rate or percentage of immunized in a population required
for herd immunity depend on? - ANSWER-the rate or percentage of immunized in a
population required for herd immunity depends on
1. how contagious the pathogen is and
2. the mode of transmission of the pathogen
What diseases have risen in cases for the past years? - ANSWER-- there's been a rise
in measles, mumps, and rubella just because many people don't want to vaccinate
- pertussis (whooping cough) because it sucks and only lasts for 3 years and then
immunity wanes
What have we eradicated with vaccines? - ANSWER-- polio
- smallpox
- diptheria
How can a vaccine make you sick? - ANSWER-if the pathogen-based vaccine is a live
strain, it can get you sick
What types of pathogens are we exposed to on a daily basis? - ANSWER-1. bacteria
2. viruses
3. fungi
4. parasites
Tell me about rotavirus! - ANSWER-- it is a virus that effects the intestinal system
- causes severe diarrhea in kids, and is fatal in infants
- there's a vaccine called rotatech, which has almost eliminated the cases of rotavirus
Tell me about mycobacterium tuberculosis! - ANSWER-- causes tuberculosis
- there's a vaccine for tb, but not commonly used in the US (much more used in
developing + 3rd world countries)
- because we don't get vaccinated for it, we need to be tested and screened for it before
we work in a healthcare setting/go to school/travel
Tell me about candida albicans! - ANSWER-- causes thrush (yeast infection of the
mouth/genitals) which is common in newborns and during antibiotic treatment
- opportunistic infection (only really affects us if homeostasis is off, we're
immunocomromised, or if antibiotics kill off all our needed bacteria, allowing yeast to
overgrow)
Complete Solutions
What is an antigen? - ANSWER-pretty much anything that the immune system
recognizes as a or port of a pathogen
- could be a protein, polypeptide, sugar residue, etc
What is immunity? - ANSWER-a state of protection against foreign pathogens or
substances (antigens)
Tell me about the observations of immunity in history! - ANSWER-- Thucydides, an
ancient historian, wrote in 430 bc of a plague in Athens where those who had recovered
from the plague could safely nurse/help the currently ill
- showed that if you had already had the illness, you were able to be around people who
currently had that illness
- modern day example: if you've had chicken pox before when you were a kid, you now
will not get it anymore even if you're around people who have it
Can we generate immunity without inducing disease? - ANSWER-YES!!
via vaccination!
What do vaccines do? - ANSWER-Prepares the immune system to eradicate an
infectious agent before it causes disease
- classic examples:
--> SMALLPOX
--> RABIES
Tell me about smallpox! - ANSWER-- Edward Jenner noticed that milkmaids were
immune to smallpox
- his hypothesis: they were immune because they were exposed to a less severe cow
pox virus (that was similar to smallpox)
- so hypothesized that if he took some puss from a cowpox blister and injected into
humans, we could be granted immunity to smallpox
--> actually inoculated 8-year old boy with cowpox puss, and then a couple weeks later
exposed him to smallpox and IT WORKED! the boy was granted immunity against
smallpox because he was exposed to the less severe cowpox virus
Tell me about rabies! - ANSWER---> Louis Pasteur worked with attenuated (weakened)
strains of rabies virus
,---> young boy bitten by rabid dog and thought if give young boy some attenuated
(weakened) rabies virus cultures, he could stop rabies from infecting the boy and IT
WORKED!
- rabies virus weird example because can administer vaccine AFTER bitten by rabid
animal
- rabies virus infects the central nervous system, so it takes some time for the virus to
actually spread to the CNS past the blood brain barrier!
---> helped the boy gain immunity to the rabies infection before it reached the blood
brain barrier
What is Edward Jenner credited for? - ANSWER-Developing the vaccine for small pox
What did Louis Pasteur find? - ANSWER-- found that can attenuate pathogens and use
them as vaccines
What are the two ways to attenuate a pathogen to make it a vaccine? - ANSWER-1.
AGE a culture to create an attenuated strain of the bacteria
2. HEAT-TREAT a culture to attenuate it!
Tell me about attenuation as vaccination! - ANSWER-- injected chicken (fowl) with
cholera, which then died
- then injected aged culture of cholera bacterium into a healthy chicken, and it didn't die
- then took fresh culture of cholera bacterium and injected into old chicken which
already survived a prior injection of cholera, and chicken lived!
--> we now know that it was because the old chicken was exposed to the
ATTENUATED strain which provided it an immune response to prevent it from dying
from cholera
- positive control: then gave fresh culture of cholera and injected into normal healthy
chicken that were not exposed to any bacteria and it died
- then did the same thing with bacillus anthracis, the bacteria that causes anthrax, but
instead inoculated sheep with HEAT treated bacillus anthracis
What is attenuation? - ANSWER-reducing the virulence of a culture (reduce the ability
to cause an infection)
"Virulence is reduced." What does that mean? - ANSWER-the ability to cause an
infection is reduced
Tell me about vaccination is a worldwide enterprise! - ANSWER-- if there's two people
that are infected without vaccine in a population of healthy unvaccinated people, the
majority of the population will become infected
,- if there's two people that are infected without vaccine in a population with 6 people that
were immunized against the pathogen/had the illness already and recovered, the
majority of the population will be infected, but the 6 people will be immune to it (because
there's a large reservoir of people who are not immunized)
- if there's two people that are infected without vaccine in a population with the majority
of people that are immunized against the pathogen, herd immunity allows most people
in the population to be immune to be safe from the pathogen
--> HERD IMMUNITY: if you have a large population of immunized individuals, those
individuals protect the non-immunized individuals
Describe herd immunity. - ANSWER---> HERD IMMUNITY: if you have a large
population of immunized individuals, those individuals protect the non-immunized
individuals
- if there are very few hosts that are susceptible to a pathogen, that pathogen cannot
spread through that population
What are two cases where herd immunity and vaccinations are very much needed? -
ANSWER-- HOSPITALS: hospital staff (healthy individuals) are vaccinated to protect
those who are too vulnerable (too young or too old to get vaccinations)
- college campuses also require students to be vaccinated to prevent the spread of
infection through the population
What are the social benefits of herd immunity? - ANSWER-- protect those that are
unable to be vaccinated (children, elderly, and immunocompromised) from being
infected
- can lead to disease being eradicated
- if can prevent people from getting sick, can reduce healthcare costs
- can control spread of disease
What are the negatives associated with herd immunity? - ANSWER-- belief that
vaccines don't work and your body can find immunity on its own
- can lead to overpopulation
- we're forcing people to do something they may not want to do
What are the two ways that a susceptible population can become IMMUNE to a
pathogen? - ANSWER-1. INFECTED: become exposed to the infection
2. IMMUNIZED: become exposed to the vaccine
Tell me about the hope of herd immunity! - ANSWER-the hope is that there are enough
people that have gained immunity to the pathogen via being infected or immunized, in
order to protect the part of the population that is susceptible to the pathogen
If talking about the flu, need what immunization rates to have immunity? - ANSWER-70-
80% of population needs to be vaccinated to have herd immunity
, If talking about the measles, need what immunization rates to have immunity? -
ANSWER-need close to 100% immunization rate in order to have herd immunity!!
because extremely contagious and exists in airborne state for a long period of time
What are the 2 things that the rate or percentage of immunized in a population required
for herd immunity depend on? - ANSWER-the rate or percentage of immunized in a
population required for herd immunity depends on
1. how contagious the pathogen is and
2. the mode of transmission of the pathogen
What diseases have risen in cases for the past years? - ANSWER-- there's been a rise
in measles, mumps, and rubella just because many people don't want to vaccinate
- pertussis (whooping cough) because it sucks and only lasts for 3 years and then
immunity wanes
What have we eradicated with vaccines? - ANSWER-- polio
- smallpox
- diptheria
How can a vaccine make you sick? - ANSWER-if the pathogen-based vaccine is a live
strain, it can get you sick
What types of pathogens are we exposed to on a daily basis? - ANSWER-1. bacteria
2. viruses
3. fungi
4. parasites
Tell me about rotavirus! - ANSWER-- it is a virus that effects the intestinal system
- causes severe diarrhea in kids, and is fatal in infants
- there's a vaccine called rotatech, which has almost eliminated the cases of rotavirus
Tell me about mycobacterium tuberculosis! - ANSWER-- causes tuberculosis
- there's a vaccine for tb, but not commonly used in the US (much more used in
developing + 3rd world countries)
- because we don't get vaccinated for it, we need to be tested and screened for it before
we work in a healthcare setting/go to school/travel
Tell me about candida albicans! - ANSWER-- causes thrush (yeast infection of the
mouth/genitals) which is common in newborns and during antibiotic treatment
- opportunistic infection (only really affects us if homeostasis is off, we're
immunocomromised, or if antibiotics kill off all our needed bacteria, allowing yeast to
overgrow)
