Vaccinations Flashcards
purpose of vaccines
provide an individual with the PRIMARY immune response to pathogen
factors allowing vaccines to be effective?
- doesn’t cause latency
- doesn’t have much antigenic variation
- doesn’t interfere with host immune response
vaccines also most effective against infections that are limited to human hosts
herd immunity
sufficient number of immune individuals in a population
-to stop transmission of infection
**proportion depends on severity of infection
passive immunization
uses pre-synthesized antibodies
- prevent disease after known exposure
- protect immunosuppressed patients
-ex/ snake bite venom
also, passive transfer of mom Abs to child
active immunization
delayed but more permanent
ex/ natural exposure to pathogens and vaccines
combined passive-active immunization
give immediate and lasting protection
ex/ tetanus, rabies
**must be given in different sites of body
how to make vaccine?
whole or part of microorganisms administered to prevent infectious disease
isolate something that:
- does not cause disease
- does cause immune response
types of vaccines?
acellular, killed organisms, attenuated, toxoid, mimic, subunit, DNA plasmid
killed organism vaccine?
inactivated or killed microorganism
ex/ polio
acelllular vaccine?
use antigen part of disease causing organism
ex/ DTap
attenuated vaccine?
can be attenuated by environmental conditions or genetic engineering
reduce virulence but still keep it viable
toxoid vaccine?
made from inactivated toxic compounds that cause illness rather than the micro-organism
ex/ tetanus
mimic vaccine?
use organisms similar to virulent one but doesn’t cause harm
ex/ vaccinia
subunit vaccine?
utilizes techniques of genetic engineering
requires adjuvant
uses subunit of virulent organism
DNA plasmid vaccine?
mimics live attenuated vaccine preparation
-circular DNA plasmids expressing specific proteins injected with presentation of protein to immune system
ex/ HIV in development
vaccinia vector
thimersol
used as preservative in vaccines
can be converted to methyl-mercury (neurotoxin)
no longer used
adjuvants
bring antigen into contact with immune system
aluminum hydroxide
only FDA approved adjuvant
clumps with antigen to keep it at the injection site
immunization schedule for child
produce immunity to virulent organisms likely to be encountered early in life
consider:
- timing of likely exposure
- immunological maturity of child
- passively transferred antibodies
- boosters for priming
parenteral route?
subQ, IM, or intradermal
stimulates IgG
oral route?
stimulates IgA
contraindications to immunization?
febrile illness immunosuppressive therapy recent blood transfusion simultaneous vaccination of another vaccine immunodeficiency pregnancy leukaemia or lymphoma
vaccines for special populations?
influenza - children and elderly
hep A, typhoid, west nile, yellow fever - travelers
rabies - animal workers
adverse reaction to vaccines?
not totally safe
-no perfect vaccine
undesirable side effects
new vaccine strategy?
use recombinant DNA technology
