1

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

2

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

3

Edward Jenner

Discovery of small pox vaccine

5

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

7

Different modes of acquiring immunity

Different modes of acquiring immunity

Natural resistance

Artificial Natural

Passive

Artificial Natural

Active

Immunity

Acquired

8

Natural Artificial

Colostral transfer of IgA

Placental transfer of IgG

Antibodies or immunoglobulins

Immune cells

Passive ImmunityPassive Immunity

9

 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

10

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

11

Active ImmunizationActive Immunization

Natural Artificial

exposure to sub-clinical infections

Attenuated organisms

killed organisms

sub-cellular fragments

toxins

others

12

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

13

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

14

Microbial Fragment VaccinesMicrobial Fragment Vaccines

Bordetella. Pertussisvirulence factor protein

Haemophilus influenzae Bprotein conjugated polysaccharide

Streptococcus pneumoniaePolysaccharide mixture

Neisseria meningitidispolysaccharide

19

ATTRIBUTES OF A GOOD VACCINE

Appropriate immune response

Long-term protection

Safe

Stable

Affordable

20

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

21

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)

25

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

26

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

29

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!

30

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

31

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)

32

Vaccines Safety

Checking vials, ampules when applicable,

and labels.

Storing vaccine

Checking vaccine and diluent vials/ampules

Checking the vaccine vial monitors

33

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

34

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)

35

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.

36

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

37

38

Freeze Watch

39

Freeze-tag

Shelf life is 5 years.

40

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.

41

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

42

43

44

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

45

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

46

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