Vaccines Flashcards
active immunity
protection produced within the person
self-generated
results from:
- antigen exposure
- pathogen exposure
- natural infection
- vaccine induced immunity
passive immunity
pre-formed protection
received externally
temporary
when immediate immunity is needed
what are some examples of passive immunity?
outbreaks
post exposure prophylaxis
- rabies
- HIV
- Hep B
maternal antibodies
- protects baby for first 6 months
IgG for rabies
vaccines
simulate immune response without causing disease
what are the 2 outcomes of vaccines?
complete protection
partial protection (mild symptoms)
vaccine induced immune responses (primary and secondary)
primary
- induced by vaccine
- slow
- few antibodies produced
- 7-14 days
secondary
- induced by prior exposure
- faster
- more antibodies produced
- 1-2 days
when should you vaccinate before travelling?
7-14 days
length of primary vaccine induced immune response
how do vaccines work?
- contain weakened, inactivated or specific pathogen components
- deliver antigens to immune system
- activation of B and T cells
- B cells produce antibodies, T cells destroy infected cells
- memory B and T cells for for future immunity
what are the 7 vaccine strategies?
- live attenuated
- inactivated (killed)
- polysaccharides
- toxoid
- subunit
- mRNA
- recombinant
live attenuated vaccine
weakened pathogen
what vaccine produces the best immune response?
live attenuated
can replicate
what are some examples of live attenuated vaccines?
MMR
varicella
rotavirus
yellow fever
what vaccines are contraindicated in immunocompromised and pregnancy?
live attenuated
inactivated (killed) vaccine
contain pathogens killed with heat or chemicals
safer for immunocompromised (can’t replicate)
not as immunogenic (require boosters)
what do inactivated vaccines often require?
boosters
what are some examples of inactivated (killed vaccines)?
hep A
influenza
polysaccharide vaccine
outer coating of bacteria
short-lived immunity
what are some examples of polysaccharide vaccines?
Hep B
pneumococcus
meningococcus
toxoid vaccine
inactivated bacterial toxins
what are some examples of toxoid vaccine?
diptheria
pertussis
tetanus
subunit vaccine
specific pathogen protein pieces
what are some examples of subunit vaccines?
pertussis
pneumococcus
mRNA vaccine
instructs cell to produce viral protein
what is an example of an mRNA vaccine?
COVID
recombinant vector vaccine
uses harmless bacteria/virus as vector
what is an example of a recombinant vector vaccine?
Hep B
what are some characteristics of a good viral vector?
stable
safe
immunogenic
doesn’t integrate into host DNA
what are some properties of a good vaccine?
stable
easy to transport
long-term protection
cost effective
individual vaccine protection
protects vaccinated person
community vaccine protection (herd immunity)
reduces risk of transmission among population
requires 70-90% of population to be vaccinated to stop the spread
herd immunity is not effective for ___________________
respiratory tract infections
what is the herd immunity threshold for measles?
95%
what is the herd immunity threshold for pertussis?
94%
what factors influence vaccine efficacy?
compliance
environment
population density
immune status
infectiousness of disease
vaccines are the most _____________________________-intervention
effective public health intervention
what diseases were eradicated with vaccines?
smallpox
rinderpest
