This document discusses immunization and vaccination. It defines immunization as inducing immunity artificially through vaccines or toxoids, which can be active or passive. Active immunization uses vaccines to stimulate antibody production, while passive immunization provides temporary protection through antibody administration. The immune response depends on factors like age, route of administration, vaccine nature, genetics, and potency. Vaccines can be live organisms, nonliving organisms, or subunits, and confer different lengths of protection. Standard immunization schedules and storage temperatures are outlined for vaccines in expanded immunization programs. Potential side effects and contraindications of specific vaccines are also detailed.

1. Immunization
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2. Immunization/Vaccination
Vaccination: is the administration of any vaccine
or toxoid for prevention of disease.
Immunization: is the process of inducing
immunity artificially.
• It can be active or passive

3. Immunization cont…
• Active immunization involves stimulating the
immune system to produce antibodies against
infectious agent through the use of vaccine or
toxoid.
• Passive immunization provides temporary
protection through the administration of
exogenous antibody or maternal antibody
transfer to the fetus.

4. Determinants of the Immune response
• The nature and magnitude of the response to a
vaccine or toxoid depend on the following
factors:
1. Age: presence of high concentration of
maternal antibody and immature response to
some vaccines in the first four months of life
impair immunization.
e.g. The measles vaccine is given at 9 months of
age to reduce this effect.

5. Determinants of the Immune response cont…
2. Route of administration: Vaccines given
orally induce mucosal secretary IgA. e.g. OPV
vaccine
• Using an improper route to administer the
vaccine may reduce the immune response
e.g. where BCG is administered IM rather than
intradermal

6. Determinants of the Immune response cont…
3. Nature of vaccine
• Live attenuated vaccines induce immunity with
a single dose which lasts longer than
inactivated ones
4. Genetic
• Individuals genetically vary in their ability to
respond to the same vaccine.
5. Potency
• Ensuring the potency of a vaccine, especially
live attenuated, requires keeping the cold chain.

7. Biologic nature of immunizing agents
• Active immunization uses vaccines with different
physical characteristic.
• They can be grouped based on their biologic nature as:
1. Living organism
– Natural: e.g. Small pox vaccine.
– Attenuated: e.g. Polio (Sabin) OPV, Measles, Mumps,
Rubella, BCG

8. Biologic nature of immunizing agents cont…
2. Intact but nonliving organisms
– Virus: e.g. Polio (Salk)
– Bacteria: e.g. Pertussis
3. Sub cellular Fragments
– Capsular disaccharide: e.g. Meningococcal
– Surface antigen: e.g. Hepatitis B.
4. Toxoids: e.g. Tetanus, diphtheria

9. Biologic nature of immunizing agents cont…
• Live attenuated vaccines, particularly viral ones
like measles, confer life long protection after a
single immunizing dose. Their drawbacks are:
– Reversion to wild type can lead to disease
– They can cause severe disease in immunocompromised
children
– Some people exhibit hypersensitivity to viral antigens.

10. Preparations: The vaccines need to keep them in
specified environmental conditions, particularly
the temperature ranges.
Vaccines for routine (EPI) use in children
Type of vaccine Storage temperature
Most
sensitive
to heat
Oral polio -15℃ to – 25℃
Measles (freeze dried) -15℃ to – 25℃
DPT, Hep-B, Hib, PCV 2℃ to 8℃
Least
sensitive
to heat
BCG (freeze dried) 2 ℃ to 8℃
Tetanus toxoid, Rota virus 2 ℃to 8℃

11. Injection safety procedures in immunization
• Injections are safe when they are not a health threat to
the recipient, health worker, the community or the
environment.
Factors that contribute to unsafe injection are:
– Reuse of syringe and needle
– Inadequate supply of injection material
– Inadequate disposal of used syringes and needles

12. • Guidelines on injection safety include:
– Use of a single sterile syringe and needle for each
dose of vaccine
– Use of auto-disable syringes preferably
– Provision of safety boxes for disposal of used
syringes
– Incineration of full safety boxes
– Removal and proper burial of residue from the
incinerator
– No disposal of used syringe, needle or full safety
boxes in open garbage or dumped randomly.

13. Expanded program of immunization (EPI)
• EPI given for the following disease or causative
agents in developing country.
1. Measles (MMR)
2. Diphtheria
3. Pertussis
4. Tetanus
5. Polio
6. Tuberculosis
7. Hepatitis B
8. Homophiles influenza type –b (Hib)
9. Rota virus
10. Pneumococcal conjugate virus (PCV)
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14. Vaccination Schedules
Contact Vaccine
At birth BCG, OPV0
6th week DPT1, HepB1, Hib1, PCV1, Rota1, OPV1 & BCG
(if not given at birth)
10th week DPT2, HepB2, Hib2, PCV2, Rota2 & OPV2
14th week DPT3, HepB3, Hib3, PCV3 & OPV3
9th month Measles & Vit A

15. Dose, route & site of administration.
Vaccine Dose Route Site
BCG 0.05ml for under
one & 0.1ml for
above one year
Intradermal Upper left/right arm
DPT 0.5 ml Intramuscular Outer part of thigh
HepB 0.5 ml Intramuscular Outer part of thigh
Hib 0.5 ml Intramuscular Outer part of thigh
PCV 0.5 ml Intramuscular Outer part of thigh
OPV 2 drops Oral
Measles 0.5 ml Sub-cutaneous Upper left/right arm
Vitamin A 1 capsule Oral

16. Vaccines in special circumstances
• Measles and meningococcal meningitis outbreak call
for the use of different vaccination schedule.
• In case of emergency setting (displacement or
war) & measles outbreak:
– Vaccinate all children between 6 month & 5 yr.
– Provide vit. A if not provided in the preceding
month

17. Side effects of vaccines
BCG:
▪ Koch`s phenomenon – self limiting acute
inflammatory reaction four days after vaccination.
▪ Indolent ulcer – ulcer persisting 12 week after
vaccination or ulcer more than 10mm, mainly resulting
from deep injection or secondary infection.
▪ Deep abscess – abscess at site of injection or draining
lymph nodes due to subcutaneous or deep injections.
▪ Disseminated disease with BCG: 1 per million
vaccines results in BCG causing active disease
especially in immunosuppressed children.

18. Side effects of vaccines cont…
OPV: Paralytic polio from vaccine strain poliovirus
DPT: The major side effect is from the pertussis
component
– Superficial injection can cause injection site abscess a
week later.
– Encephalopathy ( 0.3 – 3/100,000 vaccines)
– Convulsion (0.3 – 90/100,000)
– Shock like state or collapse (0.5 – 30/100,000)
– Permanent brain damage (0.2 – 0.6/100,000)

19. Side effects of vaccines cont…
Measles: May have mild reaction likes low grade fever,
irritability and allergic reactions.
Major side effects include (per 100,000 vaccinations):
– Encephalopathy (0.1)
– Convulsions (0.02 – 100)
– Sub acute sclerosing panencephalitis (0.01 – 0.05)

20. Contraindications
• There are circumstances in which a vaccine,
either first dose or repeat, should not be given.
• The general contraindications for all vaccines
include:
– Anaphylactic reaction
– Moderate to severe illness
– Live-attenuated vaccines for severely
immunosuppressed patient (exception is measles)

21. The contraindications for specific vaccines include:
BCG: Symptomatic AIDS
OPV: Severe immune suppression
DPT:
• Encephalopathy within 7 days of previous dose not
attributable to another cause
• Seizures if poorly controlled or new onset.
Contraindications cont…

22. The following precautions are necessary:
• Temperature greater than or equal to 40.5 ⁰C within 48
hr. of prior dose
• Shock like state
• Convulsion within 3 days after prior dose
• Persistent or inconsolable cry (greater than 3hr), within
48 hr of prior dose
• Gillian – Barrie syndrome within 6 week after prior
dose
Precautions

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