1 milestones in immunization u 1500bc u turks introduce variolation u 1885ad u pasteur discovers...
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Milestones in immunizationMilestones in immunization
1500BC Turks introduce
variolation
1885AD Pasteur discovers
rabies attenuated vaccine
3000BC Evidence of sniffing
powdered small pox crust in Egypt
2000BC Sniffing of small
pox crust in China
1700AD Introduction of
variolation in England and later in the US
1780AD Edward Jenner
discovers small pox vaccine
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The wife of the British Ambassador in Turkey, in March 1717 wrote, followingthe variolation of her son, to a friend inEngland: “The small pox, so fatal, so general amongst us, is entirely harmless here by the invention of ingrafting….I am patriot enough to bring this invention into fashion in England.
The wife of the British Ambassador in Turkey, in March 1717 wrote, followingthe variolation of her son, to a friend inEngland: “The small pox, so fatal, so general amongst us, is entirely harmless here by the invention of ingrafting….I am patriot enough to bring this invention into fashion in England.
Introduction of variolationIntroduction of variolation
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Edward Jenner
Discovery of small pox vaccine
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1920s
Diphtheria and Tetanus
1934
Pertussis
1955
Salk polio
1960s
Mumps measles and rubella virus
Sabin polio
1990s
Hepatitis and varicella
1985
Haemophilus
Modern era of the vaccineModern era of the vaccine
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Different modes of acquiring immunity
Different modes of acquiring immunity
Natural resistance
Artificial Natural
Passive
Artificial Natural
Active
Immunity
Acquired
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Natural Artificial
Colostral transfer of IgA
Placental transfer of IgG
Antibodies or immunoglobulins
Immune cells
Passive ImmunityPassive Immunity
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disease indicationantibody source
Passive ImmunizationPassive Immunization
human, horsediphtheria, tetanus prophylaxis, therapy
vericella zoster human immunodeficiencies
gas gangrene, botulism, snake bite, scorpion sting
horse post-exposure
rabies, human post-exposure
hypogamma-globulinemia
human prophylaxis
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Advantages Disadvantages
serum sicknessimmediate protection
no long term protection
graft vs. host disease (cell graft only)
risk of hepatitis and Aids
Advantages and Disadvantages of Passive Immunization
Advantages and Disadvantages of Passive Immunization
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Active ImmunizationActive Immunization
Natural Artificial
exposure to sub-clinical infections
Attenuated organisms
killed organisms
sub-cellular fragments
toxins
others
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tuberculosisused at birth
polio*used in std. schedule
measles, mumps & rubellayellow fever
Military and travelersVaricella zoster
children with no history of chicken pox
hepatitis A
not required in our country
Live Attenuated VaccinesLive Attenuated Vaccines
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polio
influenzaelderly and at risk
typhoid, cholera, plagueepidemics and travelers
rabiespost exposure
pertussis replaced by the acellular vaccine
Killed Whole-Organism VaccinesKilled Whole-Organism Vaccines
Q feverpopulation at risk
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Microbial Fragment VaccinesMicrobial Fragment Vaccines
Bordetella. Pertussisvirulence factor protein
Haemophilus influenzae Bprotein conjugated polysaccharide
Streptococcus pneumoniaePolysaccharide mixture
Neisseria meningitidispolysaccharide
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ATTRIBUTES OF A GOOD VACCINE
Appropriate immune response
Long-term protection
Safe
Stable
Affordable
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RESPONSE TO IMMUNIZATION
Depends on
Viability of antigen
Total doseespecially killed vaccine
Route and site of administration
Age of recipient
Patient’s condition and immune state
Genetic factors
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TYPES OF ANTIGENS
1. Live attenuated (oral polio, BCG, VZV)
2. Killed vaccine (influenza, IPV, Hepatitis A, pertussis)
3. Toxoid (tetanus, diphtheria)
4. Purified (subunit) antigen (Meningococcalvaccine, Haemophilus influenzae vaccine)
5. Recombinant antigen (hepatitis B)
6. DNA vaccines (in investigational phase)
7. Synthetic peptides (in investigational phase)
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PURIFIED (SUBUNIT) ANTIGEN
Only parts of pathogen necessary to elicit the immune response are used
Potential toxins are avoided
Need to be conjugated to evoke an adequate T-cell response
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POLYSACCHARIDE CONJUGATE VACCINES
Polysaccharide/oligosaccharide of antigen is linked (conjugated) to a protein carrier– increases antibody response and increases of production of
memory cells– immunologic response at earlier age
– booster effect on subsequent exposure to antigen (via infection /immunization exposure)
E.g. meningococcal vaccine, Haemophilus influenzae type B (Hib) vaccine
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COMPONENTS OF THE VACCINE FORMULATION
Suspending agents e.g. water, saline Preservatives e.g. thiomerosal Stabilisers e.g. sorbitol and hydrolyzed
gelatin - MMR Adjuvants e.g. aluminium Salts
Other substances which may be present Residuals in the growth medium Antibiotics, e.g. neomycin, streptomycin - IPV, varicella vaccine
consider these components as well when assessing causality!
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COMBINATION VACCINES
Diphtheria-tetanus-pertussis (DPT) – pertussis component has adjuvant effect for diphtheria and tetanus toxoids
Different viruses in one vaccination e.g. OPV-type 1, 2, 3 polioviruses
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ROUTE OF ADMINISTRATION
Should elicit immune response with minimal risk
Deep IM preferable for vaccines with adjuvants (depot effect and less granuloma formation)
SC/intradermal - better for live vaccines to lessen risk of neurovascular injury but still immunogenic (e.g. BCG)
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Vaccines Safety
Checking vials, ampules when applicable,
and labels.
Storing vaccine
Checking vaccine and diluent vials/ampules
Checking the vaccine vial monitors
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Checking Vials (Ampules) and Labels
1. Label
2. Age of the vaccine (expiration)
3. Signs of contamination
4. Exposure to freezing
5. Exposure to excessive heat
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Assessing Contamination
If leaks or cracks are present, discard it Change in appearance or floating particles
are seen, discard it If submerged in water, discard it If pierced with used needle, discard it If vaccine was reconstituted more than 6
hours before, discard it Vial opened for more than 4 weeks, discard
it (WHO)
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Assessing Exposure to Freezing
DPT, DT, Td, TT, hepatitis B, diluents and Hib should be discarded if you highly suspect or are certain that they are/were frozen
“Shake taste” DPT, DT, Td and TT (contain aluminum hydroxide adjuvant) when refrigerator log shows subfreezing temperatures. If failed, discard.
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Assessing Exposure to Freezing
Hepatitis B and Hib vials should be
discarded if frozen or suspected of
freezing. The “shake test” doesn’t work
for them.
Frozen diluent vials may crack, allowing
contamination of the diluent, discard it
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Freeze Watch
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Freeze-tag
Shelf life is 5 years.
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Assessing Exposure to Heat
Vaccine Vial Monitor (VVM) Present:– If VVM inner square is the
same color or darker than the outside circle, discard the vial
Vaccine Vial Monitor (VVM) Not Present:– Check temperature log and
cold-chain monitoring cards. If exposed to temperatures above 8º C, discard it.
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Checking Vaccine Vial Monitors
VVM is a label made of heat-sensitive
material, placed on the vial to show
cumulative heat exposure over time
VVM reduces waste of vaccine,
ensuring that only good vaccine is used
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Storage
Fill syringe only when patient is ready to receive an injection
Do not combine partially opened vials Keep opened vials in the refrigerator in
a special box marked “returned”, but remember to discard reconstituted vaccines after 6 hours of reconstitution
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Storage
ThermostatThermostat
Ice Packs in freezing
compartment
Ice Packs in freezing
compartment
“Returnedbox
“Returnedbox
Oral Polio, MeaslesOral Polio, Measles
BCG, DPT, TT, diluentBCG, DPT, TT, diluent
Ice packsIce packs
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Checking the Vaccine and Diluent Vials
Before use, check the following:– Is the label still attached to the vial?– Is the right vaccine and right diluent?– Expiration date?– Contamination (discard reconstituted vaccine 6
hours after reconstituted)– Cold sensitive vaccines show no signs of
freezing– No signs of heat exposure