VBS 2032: EXAM 3 Questions and Correct
Answers
Active immunity
when body produces its own immune response and memory cells (long lasting, slower)
Passive immunity
when antibodies are received from another source (short term, fast, no memory)
Variolation
early method of immunization using live smallpox virus from infected individuals to induce a
mild infection and immunity
How does variolation differ from smallpox vaccination?
variolation uses the actual smallpox virus and is risky, while vaccination uses a safer related
virus (cowpox) to provide immunity without causing severe disease
Who discovered the smallpox vaccine?
Edward Jenner
Attenuated vaccine
vaccine composed of a weakened form of the pathogen that is unable to cause disease
Example of a combination attenuated vaccine
MMR vaccine (measles, mumps, rubella)
rVSV-ZEBOV Ebola vaccine
,recombinant vaccine that uses vesicular stomatitis virus engineered to express an Ebola virus
protein, triggering an immune response without causing Ebola
Toxoid vaccine
vaccine made from an inactivated toxin that stimulates immunity against the toxin rather than the
pathogen itself
Example of toxoid vaccine
tetanus
Inactivated polio vaccine (IPO)
injected, contains killed virus, and is very safe but provides less gut immunity
Oral polio vaccine (OPV)
taken orally, contains live attenuated virus, and provides strong intestinal immunity
When wild poliovirus is circulating, which vaccine is preferred?
OPV, because it provides strong intestinal immunity and helps stop transmission
What is a risk of the oral polio vaccine (OPV)?
it can rarely mutate back to a virulent form and cause vaccine-derived polio
Why can't immunocompromised individuals receive attenuated vaccines?
their immune systems may not control even the weakened pathogen, leading to disease
Can pregnant women receive attenuated vaccines?
no, because of potential risk to the fetus
,Why are boosters necessary for subunit vaccines?
subunit vaccines produce a weaker immune response, so boosters are needed to maintain
immunity and memory
Why are adjuvants sometimes necessary in vaccines?
they enhance the immune response, making the vaccine more effective
Why does the conjugate Hib vaccine work better than a polysaccharide-only vaccine?
conjugation to a protein allows T-cell involvement, leading to stronger and longer-lasting
immunity, especially in children
How does an RNA vaccine work?
it delivers mRNA into cells, which then produce a viral protein that triggers an immune response
and memory formation
What are advantages of RNA vaccines?
rapid development, no live virus needed, strong immune response, and safe for
immunocompromised individuals
What types of COVID-19 vaccines have been developed?
mRNA vaccines, viral vector (adenovirus-based) vaccines, protein subunit vaccines, and
inactivated virus vaccines
How do clinical trial phases differ?
phase 1 tests safety (small group), phase 2 tests effectiveness and dosing (hundreds), phase 3
tests large-scale efficacy and safety (thousands)
, Why are preclinical trials necessary?
to test safety and immune response in cells and animals before human trials
How do RNA COVID-19 vaccines stimulate immunity?
mRNA enters cells, cells produce viral proteins, immune system responds, and memory cells
form
How do adenovirus-based COVID-19 vaccines stimulate immunity?
a modified virus delivers DNA for a viral protein into cells, which produce the protein and
trigger an immune response with memory
How are antibiotics administered to livestock like chickens and turkeys?
they are commonly given through feed or drinking water, and less commonly by injection
How can antibiotics given to people, pets, or livestock circulate in the environment?
through waste (urine/feces), runoff into water systems, contamination of soil, improper disposal
of medications, and spread via food products
How can antibiotic resistance spread within a healthcare system?
through contaminated surfaces, medical equipment, healthcare workers, and patient-to-patient
transmission
How can antibiotic resistance spread between people?
through direct contact, respiratory droplets, poor hygiene, and shared environments
How can antibiotic resistance spread between bacteria?
Answers
Active immunity
when body produces its own immune response and memory cells (long lasting, slower)
Passive immunity
when antibodies are received from another source (short term, fast, no memory)
Variolation
early method of immunization using live smallpox virus from infected individuals to induce a
mild infection and immunity
How does variolation differ from smallpox vaccination?
variolation uses the actual smallpox virus and is risky, while vaccination uses a safer related
virus (cowpox) to provide immunity without causing severe disease
Who discovered the smallpox vaccine?
Edward Jenner
Attenuated vaccine
vaccine composed of a weakened form of the pathogen that is unable to cause disease
Example of a combination attenuated vaccine
MMR vaccine (measles, mumps, rubella)
rVSV-ZEBOV Ebola vaccine
,recombinant vaccine that uses vesicular stomatitis virus engineered to express an Ebola virus
protein, triggering an immune response without causing Ebola
Toxoid vaccine
vaccine made from an inactivated toxin that stimulates immunity against the toxin rather than the
pathogen itself
Example of toxoid vaccine
tetanus
Inactivated polio vaccine (IPO)
injected, contains killed virus, and is very safe but provides less gut immunity
Oral polio vaccine (OPV)
taken orally, contains live attenuated virus, and provides strong intestinal immunity
When wild poliovirus is circulating, which vaccine is preferred?
OPV, because it provides strong intestinal immunity and helps stop transmission
What is a risk of the oral polio vaccine (OPV)?
it can rarely mutate back to a virulent form and cause vaccine-derived polio
Why can't immunocompromised individuals receive attenuated vaccines?
their immune systems may not control even the weakened pathogen, leading to disease
Can pregnant women receive attenuated vaccines?
no, because of potential risk to the fetus
,Why are boosters necessary for subunit vaccines?
subunit vaccines produce a weaker immune response, so boosters are needed to maintain
immunity and memory
Why are adjuvants sometimes necessary in vaccines?
they enhance the immune response, making the vaccine more effective
Why does the conjugate Hib vaccine work better than a polysaccharide-only vaccine?
conjugation to a protein allows T-cell involvement, leading to stronger and longer-lasting
immunity, especially in children
How does an RNA vaccine work?
it delivers mRNA into cells, which then produce a viral protein that triggers an immune response
and memory formation
What are advantages of RNA vaccines?
rapid development, no live virus needed, strong immune response, and safe for
immunocompromised individuals
What types of COVID-19 vaccines have been developed?
mRNA vaccines, viral vector (adenovirus-based) vaccines, protein subunit vaccines, and
inactivated virus vaccines
How do clinical trial phases differ?
phase 1 tests safety (small group), phase 2 tests effectiveness and dosing (hundreds), phase 3
tests large-scale efficacy and safety (thousands)
, Why are preclinical trials necessary?
to test safety and immune response in cells and animals before human trials
How do RNA COVID-19 vaccines stimulate immunity?
mRNA enters cells, cells produce viral proteins, immune system responds, and memory cells
form
How do adenovirus-based COVID-19 vaccines stimulate immunity?
a modified virus delivers DNA for a viral protein into cells, which produce the protein and
trigger an immune response with memory
How are antibiotics administered to livestock like chickens and turkeys?
they are commonly given through feed or drinking water, and less commonly by injection
How can antibiotics given to people, pets, or livestock circulate in the environment?
through waste (urine/feces), runoff into water systems, contamination of soil, improper disposal
of medications, and spread via food products
How can antibiotic resistance spread within a healthcare system?
through contaminated surfaces, medical equipment, healthcare workers, and patient-to-patient
transmission
How can antibiotic resistance spread between people?
through direct contact, respiratory droplets, poor hygiene, and shared environments
How can antibiotic resistance spread between bacteria?
