Dr.Waqas Nawaz PMAS arid agriculture university Rawalpindi

2. MICROBIOLOGY
Topic
VACCINES
SUBMITTED BY:
11-arid-974 11-arid-975
11-arid-978 11-arid-979
SUBMITTED TO: 11-arid-980 11-arid-981
11-arid-982 11-arid-983
Dr.Saif-ur-Rehman 11-arid-985 11-arid-986
11-arid-988 11-arid-990

3. What is a Vaccine?
o A vaccine is a non-pathogenic antigen that mimics a
particular pathogen in order to elicit an immune response as if
that actual pathogen were in the body.
o The overall goal of a vaccine is to establish immunity
against that particular pathogen.

4. TYPES OF VACCINES
Vaccine Examples
Immunoglobulin (IG) Varicella Zoster IG
Human Normal IG
Hep B IG, Tetanus IG
Anti-toxins Diphtheria anti-toxin
Botulinum anti-toxin
Inactivated/subunit Diphtheria/tetanus/acellular pertussis /inactivated
vaccine polio/Haemophilus influenzae b (DTaP/IPV/Hib)
Meningococcal C (MenC),
Pneumcoccal (PPV & PCV)
Human papillomavirus vaccine (HPV)
Hepatitis A vaccine (HAV)
Hepatitis B vaccine (HBV),
Live attenuated Measles, mumps and rubella (MMR),
Yellow fever

5. VACCINE COMPOSITION
Component Purpose Example
Adjuvants enhance the immune response to a aluminium salts
vaccine
Preservatives prevent bacterial or fungal contamination thiomersal
of vaccine
Additives stabilise vaccines from adverse gelatine
conditions such as freeze-drying or heat,
thereby maintaining a vaccine’s potency
Residuals from Inactivating agents formaldehyde
manufacturing
process Antibiotics - prevent bacterial neomycin, streptomycin,
contamination during manufacturing polymyxin B
process
Egg proteins- some vaccine viruses are
grown in chick embryo cells influenza, yellow fever
Yeast proteins Hep.B vaccine

6. ACTIVE VACCINE
Stimulates Humoral Immune Response,Cellular
Immune Response or Both, with the aim of
protecting against or eliminating a pathogen
PASSIVE VACCINE
Preparation of Abs, Protect against a pathogen or
disease and is administered before, at or around
the time of known or potential exposure

7. comparison of different vaccine types
LIVE VACCINES (ATTENUATED)
(MMR, Oral Polio)
Advantages:
One or few doses required
Long lasting protection
Both humoral and cellular responses
Disadvantages:
Controlled attenuation normally required
Poorly defined composition
Risk of reversion to pathogenicity
Certain risk of transmission

8. comparison of different vaccine types
KILLED VACCINES
(Polio and Influenza)
Advantages:
No risk of reversion to pathogenicity
No risk of transmission
Disadvantages:
Multiple dose typically required
Poorly defined composition
Antigen produced by cultivation of a pathogen
Mainly humoral responses
Adjuvants normally needed

9. Attenuated vaccines Killed(Inactivated) vaccines
Production Virulent pathogen is grown under Virulent pathogen is inactivated by
abnormal culture conditions for chemicals or irradiations.
attenuation
Booster Generally requires only a single Requires multiple boosters
requireme booster.
nt
Relative Less stable More stable on storage
Stability
Type of Humoral and cell mediated Mainly humoral
immunity
induced
Reversion May revert to virulent form and Cannot revert to virulent form
tendency cause disease.
Adjuvents Unnecessary Required for most vaccines
Inflammat Less chances More chances of mounting an
ory allegic reaction
response
Cost Reletively cheap Relatively costly

10. comparison of different vaccine types
TOXOIDES
(Tetanus and Diphtheria)
Advantages:
Product is devoid of live organism
Implies greater safety
Disadvantages:
Multiple dose typically required
Relatively expensive to manufacture
Cultivation of a pathogen for toxin production

11. SUBUNIT VACCINES
SUBUNIT VACCINES ARE DEFINED AS THOSE
CONTAINING ONE OR MORE
PURE OR SEMI-PURE
ANTIGENS

12. comparison of different vaccine types
SUBUNIT VACCINES (NON-RECOMBINANT)
Constituent proteins of bacteria or virus are isolated and purified
Advantages:
 Defined Composition
 Various delivery systems available
Disadvantages:
 Antigens must be produced and purified by cultivation of a
pathogen
 Multiple doses typically required
 Adjuvant needed

13. RECOMBINANT SUBUNIT VACCINES
•Identify and isolate a specific gene from
virulent bacteria or virus (gene that codes
immuno protective protein).
•Gene is inserted into plasmid DNA and
ligated with ligase.
•New (engineered) plasmid inserted into Target gene
another bacterium (transform).
•Allowed to grow and actually produce
the antigenic protein.
•The vaccine is comprised of purified
proteins recovered from the expression
vector.

14. comparison of different vaccine types
RECOMBINANT SUBUNIT VACCINES
Advantages:
 No risk of pathogenicity
 Defined composition
 Various delivery systems
 Simplified large scale production
 Further engineering possible
Disadvantages:
 Multiple doses typically require
 Adjuvants needed

15. comparison of different vaccine types
RECOMBINANT VECTOR VACCINES
 Based on microorganisms such as viruses or bacteria that do not
cause disease in target animals or humans.
 The viruses or bacteria are used as vectors, or carriers, to deliver
harmless genes into the cells of the body.
 The body produces proteins from the genes and these proteins
stimulate an immune response against the specific protein.

16. comparison of different vaccine types
RECOMBINANT GENE DELETED VACCINES
Involves isolation and removal of viral gene(s) that code for “non-
required” proteins
This process is intended to decrease the virulence of the virus
making it suitable for administration in vaccine
Advantages:
 The absence of specific antigens from the virus can be used to
differentiate between vaccine virus and natural (“wild-type”) virus.
Disadvantages:
 Potential exists for virus to revert to its original, virulent state.
 Degree of protection could be limited since immune response is

17. comparison of different vaccine types
RECOMBINANT VIRAL VECTOR VACCINES
• Isolate an immunoprotective protein gene from a virulent virus.
• Clone the gene to a vector of a non virulent virus.
• These live vectored vaccines are being used to not only control
infectious diseases of domestic animals, but of wildlife as well.
• This approach has resulted in a dramatic reduction in
transmission of RABIES from wildlife to domestic animals and
humans. This would not have been possible by conventional
methods.

18. comparison of different vaccine types
RECOMBINANT VIRAL VECTOR VACCINES
Advantages:
• Risk of reversion to virulence is eliminated if virus vector is not
capable of intracellular replication.
• Both CMI and Humoral Immunity is good if the vector is capable
of intracellular replication.
Disadvantages:
• Weak CMI response if vector is incapable of intracellular
replication.
• The vaccine utilizes very specific protective proteins. The immune
response may be reduced in some animals.

19. DNA VACCINE
Uses only the DNA from infectious organisms.
Avoid the risk of using actual infectious organism.
Provide both Humoral & Cell mediated immunity
Refrigeration is not required

20. TRANSITIONAL VACCINE
Uses weakened or killed form of infectious organism.
Create possible risk of the vaccine being fatal.
Provide primarily Humoral immunity
Usually requires Refrigeration.

21. CONTRAINDICATIONS & PRECAUTIONS
Vaccine Contraindication Precautions
All vaccines •A confirmed anaphylactic reaction to •If individual acutely unwell on day of
a previous dose of the vaccine or to a vaccination, postpone until recovered
(live and component of the vaccine
inactivated) •Pregnancy
DTP •As above •If evidence of evolving neurological
abnormality or current neurological
deterioration, including poorly controlled
epilepsy, immunisation should be
deferred until condition stabilised
Influenza •As above and additionally: •Where possible, thiomersal free influenza
vaccines recommended for pregnant
•Individuals with confirmed women and infants
anaphylactic hypersensitivity to egg
products
Live vaccines •As above and additionally: •If ITP following previous MMR vaccine,
(MMR, varicella) perform antibody test
•Immunocompromising treatment or
condition •If confirmed anaphylactic reaction to egg,
seek further advice with view to
•Pregnancy immunisation under controlled
conditions

22. CAUSES OF VACCINE
FAILURE

23. VACCINE FAILURE
• Primary failure
– an individual fails to make an adequate immune response
to the initial vaccination (e.g. in about 10% of measles
and mumps vaccine recipients)
The primary cause of vaccine failure is an interfering
level of maternal antibody.
• Secondary failure
– an individual makes an adequate immune response
initially but then immunity wanes over time (a feature of
most inactivated vaccines, hence the need for boosters)

24. Veterinary Advice: Vaccination
Failure
• vaccination 1) The clinical disease is
failure or failure of being caused by the
immunization occurs vaccine itself (live
vaccines only)
because of one of two
OR
reasons:
2) The clinical disease is
being caused by a wild-
type, infectious disease
organism that has infected
the animal from its local
environment

25. CAUSES OF VACCINE
FAILURE
• USE OF EXPIRED VACCINE • COLD AND HIGH DENSITY STRESS
• GENETIC RESISTENCE • POOR NUTRITION
• IMPROPER STORAGE OF VACCINES • PRESENCE OF AMMONIA IN HOUSES
• HEALTH STATUS OF THE FLOCK • ADMINISTRATION ERRORS QUALITY OF
WATER
• IMMUNO SUPPRESSION DUE TO DRUGS
• MATERNAL ANTIBODIES
• MYCOTOXINS
• PRESENCE OF VARIANT IN FIELD
• WATER DEPRIVATION AND HEAT STRESS
• POOR ANTIGENICITY OF VACCINES
• GEONETICS
• INTERFERENCE
• VACCINATION REATIONS

26. USE OF EXPIRED VACCINE GENETIC RESISTENCE
• Vaccines are expired by many • The major histocompatibility
ways, among the most common complex varies from bird to
are the expired in storage due bird and its structure dictates if
to sale, expired in storage due a bird will respond to an
to sale, expired due to less shelf antigen at all. Due to some
life ( it must be year plus when structural lacks in MHC it is
reached in Pakistan ) expired possibility that the birds are
supply by the manufacturer recognize the one of the
only with few months in hand. antigens. Therefore that strain
of birds might be more
susceptible to pathogen.

27. IMPROPER STORAGE OF VACCINES HEALTH STATUS OF THE FLOCK
• This is the most common cause • The infectious agents such as
of vaccine failure in routine Chicken Anemia Agent (Circo
uses of vaccines. This might be virus), Gumboro Disease Virus
due to transportation from (Birna virus), Marek’s Disease
market to farm or from Virus (Herpes Virus ), REO
manufacturer to distributor to Virus, Salmonella and
market, failure of electricity, Mycoplasma etc. may cause
failure of refrigerators, storage varying degree negative
in deep freezers, exposure of immunomodulation which
sunlight. consequently may lead to
Ignoring the use of ice box, vaccinal failure or adverse
coolers or thermos and using reaction in the face of these
the translucent thin membrane disease
shoppers permitting the
sunlight exposure.

28. IMMUNO SUPPRESSION DUE TO DRUGS MYCOTOXINS
• Presence of mycotoxin in the
• Continuous administration of feed affect the vaccinal
Immuno-suppressive drugs response very badly. Mycotoxin
such as chloramphenicol, reduce host immunity directly
furazolidone may cause cause by reducing the Macrophage
poor immunity development. engulfing tendency and
production of toxin,
lymphocytes which give poor
out put in immunity
development. Mycotoxin
indirectly affect the bird by
producing steroids from the
adrenal glands which decrease
the lymphocytes and increase
the neutrophils by the virtue of
increased nutrophil the bird
become Immune compromised.

29. WATER DEPRIVATION AND HEAT STRESS GEONETICS
• Due to water deprivation the • Means simply the geographical
bird is exposed to heat stress. influence on the geonetics of
Due to heat stress lot of steroid local poultry population. The
production do occur which geonetical influence may affect
decrease the lymphocytes the ultimate response of birds
produce the antibodies. This is to vaccine under indigenous
common observation that the environments and may result in
dehydrated and heat exposed vaccine failure. The difference
birds commonly infected with pay more if they are present in
coli septicemia and other MHC.
diseases

30. COLD & HIGH DENSITY STRESS VACCINATION REACTIONS
• These are social stress as well • Adverse vaccine reaction,
as stress like heat stress and however do not serve a useful
decrease the immunity by purpose and should be
decreasing the number of prevented if at all possible.
lymphocyte, which is the Several factors can affect the
factory of antibodies. severity of the reaction that
occur. These include:
• Chick quality
• Level of maternal antibodies
• Vaccine strain
• Doses of vaccine used
• Route of application
• Timing of vaccination
• Immuno suppression
• House sanitation
• Down time
• Water,litter and air quality

31. PRESENCE OF AMMONIA IN HOUSES
POOR NUTRITION
• Hypoproteinemia especially • On the port of entry from where the
protein hurt the immune pathogens are entered the body to
response as antibodies are produce infection there are some
host defense mechanism which
made up of amino acids. Poor
prevent the entry of pathogens.
nutrition causes problem with Hairs cilia moist membranes are
metabolism, protein synthesis among the preventive cushions.
and immunity. The moist membranes of or the
mucous membranes among the
gut , trachea, nostrils and bronchi
produce Immunoglobulin .a
through the lymphocytes present on
the surface of these organs. This is
called secretory immune
mechanism and it is watch dog on
the port of entry.

32. ADMINISTRATION ERRORS_QUALITY OF WATER
Water quality is poor in most of the areas of
Pakistan, particularly in salinity affected
areas such as Faisalabad, Sheikhupura and
Multan Division, where the salt level is half of
the sea water and EC even in Islamabad is
600-2000. Poor water quality and high salt
concentration produce ill effect on the
vaccine diluted in such kind of water.

33. PRESENCE OF VARIANTS IN FIELD
MATERNAL ANTIBODIES
• High maternal antibodies inhibit • It has been observed that with
the chicken immune response. It the emergence of new variants
has negative feed back effect on B the classical vaccines are no
lymphocytes. Moreover high levels more effective to control the
of maternal antibodies against
infectious agent such as Gumboro, disease. Classical vaccine of
also play a role in neutralizing the gumboro is missing the VP-2
vaccinal antigen thus making the protien therefore it is not
vaccine less effective and effective against field variant or
designing the vaccine program strain. The hot intermediate
more difficult. Due to high and intermediate plus do have
maternal antibodies not only the the VP-2 protein and can
vaccinal antigen is destroyed but penetrate up to the site of
also the maternal antibodies are
proliferation. In the same
also destroyed leaving the bird
exposed to field challenge if earlier manner classical IB is no more
vaccination in high titer is done. effective against IB variants.

34. POOR ANTIGENICITY OF VACCINES INTERFERENCE
• Live vaccines must be applied at a • Do not give live respiratory
level at or above the minimum vaccines (IB,ND,ILT) within 3
infective dose. After the live virus to 4 days if not combined by the
has been applied the bird serves as
manufacturer in licensed
a virus production site. The bird is
combination. Reaction may be
media in which the initial dose of
vaccine can multiply to a level too great or response to the
which will stimulate a proper later vaccine may be
immune response. For potency compromised due to
testing of vaccines, always contact interference. This is also true in
well facilitated Lab. Inactivated case of ND and AI vaccine. Do
vaccines should contain sufficient ND vaccine earlier than
amount of antigen to stimulate an proceed for AI vaccine.
immune response when applied the
bird as there is no multiplication of
the virus of bacteria in the bird.