The document outlines the principles and components of immunization, defining key concepts such as active and passive immunity, and detailing various immunizing agents, including vaccines and immunoglobulins. It also discusses the significance of the cold chain in vaccine storage and transportation, along with the history and structure of global immunization programs, including the Universal Child Immunization initiative. Furthermore, it highlights specific vaccination strategies like the Mission Indradhanush aimed at protecting children from vaccine-preventable diseases.

1. Immunization
Dr. Nidhi Fotedar
Department of Community Medicine
KIMS, Bangalore
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2. Plan of Presentation
❖ Specific Defences
❖ Immunizing agents
❖ Adverse events following immunization
❖ Immunization Programmes & Schedules
❖ Cold Chain
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3. Specific Defences
A person is said to be immune when he possesses “specific
protective antibodies or cellular immunity as a result of previous
infection or immunization, or is so conditioned by such previous
experience as to respond adequately to prevent infection and/or
clinical illness following exposure to a specific infectious agent”
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4. Specific Defences
1. Active immunity
➢ Humoral immunity
➢ Cellular immunity
➢ Combination of the above
1. Passive immunity
➢ Normal human Ig
➢ Specific human Ig
➢ Animal antitoxins or antisera
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5. Specific Defences
1. Active immunity
“ It is the immunity which an individual develops as a result of infection or by
specific immunization and is usually associated with presence of antibodies
or cells having a specific action on the microorganisms concerned with a
particular infectious disease or on its toxin”
It may be acquired in 3 ways:
(A)Following clinical infections e.g chickenpox, rubella & Measles
(B)Following subclinical or inapparent infection e.g polio, diphtheria
(C)Following immunization with an antigen which may be killed vaccine, a live
attenuated vaccine or toxoid.
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6. Specific Defences
2. Passive immunity: When antibodies produced in one body( human
or animal) are transferred to another to induce protection against
disease.
3. Herd immunity: type of immunity that occurs when the vaccination
of a portion of population(or herd) provides protection to unprotected
individuals.
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7. Immunizing Agents
“Immunization is a procedure in which immunobiological
substances are administered to strengthen the defense mechanism
as to protect the individual against the disease”
Immunizing agents are classified into three groups :
● Vaccines
● Immunoglobulins
● Antisera
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8. Immunizing Agents
Vaccines: Antigenic substances, which when administered in an
individual, stimulate the production of specific antibodies and
protect the individual against that particular disease.
● Live vaccines, killed vaccines, toxoids, recombinant vaccines,
combined vaccines, tissue culture vaccines, and related vaccines
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9. Immunizing Agents
Live vaccines: Live vaccines are prepared from live or wild( generally
attenuated) organisms; they are made to retain the antigenicity and to
loose pathogenicity.
E.g Bacillus calmette- Guerin( BCG), OPV, Measles vaccine
Measles-mumps-rubella (MMR)
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10. Immunizing Agents
Killed Vaccine; Inactivated or killed vaccines are produced by
growing virus or bacteria in culture media and then inactivating
them with heat and chemicals( usually formalin)
● Usually they are given in multiple doses in the primary
course(2-3 doses), followed by booster dose subsequently)
● E.g Cholera vaccine, anti rabies vaccine, salk polio vaccine
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11. Immunizing Agents
Toxoids: Toxins of the organisms are modified( detoxified) so as to
maintain only antigenicity and not pathogenicity(toxicity)
E.g Td
Cellular fractions: These vaccines are prepared from the extract of
the bacterial cell wall or capsule.They are also safe, effective and
require booster doses
E.g Meningococcal vaccine, pneumococcal vaccine
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12. Immunizing Agents
Subunit vaccine: This is prepared from a component of the virus.
E.g Influenza Vaccine
Recombinant Vaccine: These are genetically engineered
recombinant deoxyribonucleic acid (DNA) vaccines, i.e the subunit
of the virus (antigen) is inserted into the genome of another a
virulent virus and vaccine is prepared.E.g Hep B vaccine.
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13. Immunizing Agents
Combined vaccines: Preparation contains more than one antigen.
Therefore they are also called “mixed vaccines”. E.g Pentavalent-
Diphtheria, pertussis, tetanus, hepatitis B and Hib.
● Merits: Individual is simultaneously protected against two to
three diseases
● One antigen enhances the effect of other antigen
● Reduces number of visits to clinic
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14. Immunizing Agents
Tissue culture vaccines:These are prepared by culturing the seed
viruses in special cells, such as chick embryo cells, vero cells of
kidneys of monkeys, human embryonic lung fibroblasts, etc.
● Highly safe, highly antigenic, highly effective, highly stable,
highly protective and highly purified
● E.g purified chick embryo cell vaccine and purified vero cell
rabies vaccine
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15. Immunizing Agents
Immunoglobulins:These are readymade antibody preparations,
obtained from the human beings and produce immunity
instantaneously
Two types:
1. Human normal Immunoglobulins
2. Human-specific Immunoglobulins
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16. Immunizing Agents
Human normal immunoglobulins: This is prepared from the pooled
plasma of multiple donors. It’s a general antibody preparation and
consists of IgG. E.g against measles, it is given to susceptible
contacts. Against viral hepatitis A, it is given to those who are
travelling to endemic areas.
★ This should not be given simultaneously along with live
vaccines because IgG will interfere with the development of
immunity
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17. Immunizing Agents
Human-specific immunoglobulins:This is prepared from the plasma
of those persons, who have been recently immunized or recovered
from the disease. This is highly safe, effective, and costly
● Not only it is used for passive immunization i.e post exposure
prophylaxis, but also it is used as a part of treatment to
neutralize the circulating toxins in the patient E.g HRIG,
HTIG,VZIG
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18. Immunizing Agents
Antisera:
These are the specific Igs prepared from the plasma of immunized
animals, such as horses.
● Cheap and less effective;Immunity lasts for about 2-3 weeks only.
● Reactions are frequent because of animal protein, so test dose is a
must
E.g Equine rabies immunoglobulin, anti snake venom, anti tetanus
serum, anti diphtheria serum and anti gas gangrene serum
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19. The Cold Chain
The “ cold chain” is a system of storage and transport of vaccines at low temperature
from the manufacturer to the actual site of vaccination.
➢ Vaccines are sensitive biological products (sensitive to heat and light)i.e they lose
their potency, when exposed to heat and light.All vaccines retain their potency at
temperatures between +2℃ and +8℃
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20. The Cold Chain
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21. The Cold Chain
1. walk-in-freezer(WIF): prefabricated modular polyurethane foam
insulated panel assembled cold room with two identical
refrigeration units and a standby generator set to provide
uninterrupted power supply
★ Start as soon as power cuts off; maintains temperature between
- 15℃ to -25℃
★ WIF are usually used for bulk storage of OPV vaccine and
preparation of frozen ice packs for vaccine transportation
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22. The Cold Chain
2.walk-in-coolers(WIC):Air-conditioned cold rooms, maintaining the temperature
between +2℃ and +8℃ .
3.Deep freezer(DF): An equipment which operates on a vapour compression
system similar to any conventional type of refrigerator operating on 220 volts A.C.
main supply.
➢ DF has top opening lid to prevent loss of cold air during door opening
➢ Cabinet temperature is maintained between - 15℃ to -25℃
➢ It’s used for storing OPV vaccine for 3 months( district level and above only)
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23. The Cold Chain
4. Ice-lined refrigerator:ILRs are to maintain cabinet temperature
between +2℃ to +8℃ and are used to store vaccines at district and
sub-district level.
➢ It can keep vaccine safe with minimum 8 hours continuous
electricity supply in a minimum 8 hours continuous electricity
supply in a 24-hour period.
➢ Available in different sizes.
➢ Larger ILR is supplied to district headquarters and smaller ILR
to PHC headquarters, based on the size and population.
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24. The Cold Chain
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25. The Cold Chain
5. Cold Box:
Big, rectangular box(90 cms x 60 cms) made up of insulated
material, lined with 24 ice packs, which act as buffer and maintain
the cold life inside the box for about 5 days.
★ Such boxes are used to collect, store, and transport large
quantities of vaccines from one place to another place by
refrigerator vans.
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26. Open Vial Policy 2015
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27. Open Vial Policy 2015
A Vaccine vial monitors is a chemical indicator label attached to the vaccine
container( vial, ampoule or dropper) by the vaccine manufacturer.
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28. Immunization Programme
➢ In May 1974, the WHO officially launched a global
immunization programme, known as Expanded Programme
on Immunization to protect all children of the world against six-
vaccine- preventable diseases, namely- Diphtheria, whooping
cough, tetanus, polio, tuberculosis and measles by year 2000.
➢ Beneficiaries were all expectant mothers and children upto the
age of 16 years
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29. Immunization Programme
➢ Programme is now called Universal child Immunization-1990-
that’s the name given to a declaration sponsored by UNICEF as
part of the United nations’ 40th anniversary in october 1985.
➢ In 1995, Pulse polio Immunization Programme was launched as
a strategy to eradicate poliomyelitis
➢ In 2005, immunization schedule was revised incorporating Hep
B vaccine and 2 doses of measles vaccine and 2 doses of JE in
endemic areas.
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30. National Immunization Schedule
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31. Immunization Programme
Mission Indradhanush:MI is a health mission with positive initiative
to intensify the existing UIP with the objective of accelerating the
process of immunization and to fully immunize every child and to
protect all the children against seven vaccine preventable disease-
diphtheria, pertussis, tetanus, poliomyelitis, measles, Hep B and
childhood tuberculosis, depicting 7 colours of rainbow.
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