Vaccines

1. VACCINES

2. • Edward Jenner
• Louis Pasteur

3. Vaccines
• Vaccine is a non-pathogenic immunogen that
when given to a host, induces protective
immunity against a specific pathogen

4. Immunization
• The process of producing a state of immunity
to infectious micro-organism is called
immunization
• Active immunization
• Passive immunization

5. Active immunization & Passive immunization

6. Primary active immunization and
booster re-immunization

7. Types of vaccines for active
immunization
• Live vaccine
• Live attenuated vaccine
• Killed vaccine
• Toxoid
• Purified macromolecules as vaccines
• Recombinant antigen vaccine
• Peptide vaccine
• Genetic vaccine

10. Live vaccine
• Smallpox vaccine

11. Live attenuated vaccines
• The microbe is alive and can multiply in the
host but the microbe has lost the ability to
produce disease
• Oral Polio virus (Sabin)
• Bacillus Calmette-Guerin vaccine- id
• MMR- im
• Varicella virus- sc
• Oral typhoid vaccine

13. Adverse effects of live vaccines
• Allergic reactions
• Spread from one person to the other
Contra-indications for live vaccines
• Pregnant women
• Immunocompromised patients

14. Killed vaccines
• Pathogenic bacteria or viruses are killed by
heat or chemicals. They cannot produce the
disease but they act as antigens when
inoculated into the body

15. • Killed polio virus vaccine- Salk
• Cholera vaccine- sc, im, id
• Killed typhoid vaccine
• Plague vaccine
• Rabies vaccine- im, id
• Influenza virus vaccine

16. Difference between live attenuated and
killed vaccine
• May revert to virulent
form
• Both humoral and cell-
mediated immunity are
produced
• Less stable
• Contraindicated in
pregnant &
immunocompromised
patients
• Does not revert to
virulent form
• Mainly humoral immunity
• More stable
• Safer

17. Purified macromolecules
• Streptococcus pneumoniae, H. influenzae
• Neisseria meningitidis

18. Toxoids
• Bacterial toxins inactivated by chemicals but
retains their antigenicity
• Tetanus toxoid

19. Recombinant antigen vaccine
• The recombinant DNA technology is used to
introduce genes from a pathogenic organism
into another organism
• HBsAg
• B subunit of cholera toxin vaccine

23. Peptide vaccines
• Developed by determining the amino-acid
sequence of any microbial peptide

25. Genetic vaccines
• Experimental animals were immunized by a
naked DNA which encoded a polypeptide
antigen. The vaccinated animals developed
both humoral and cell-mediated immune
responses against the polypeptide coded by
DNA- Genetic immunization

26. DNA vaccine
Advantages:
• Natural form
• Induces both humoral and cell-mediated
immune response
• Refrigeration not required
• Easy to design

28. Recombinant vaccinia virus DNA
vaccine
Advantages:
• Vaccinia virus is safe
• Larger size of the virus- accomodates genes
from more than 2 pathogens

29. Plasmid DNA vaccine
• A gene from pathogenic microbe is inserted
into the plasmid genome.
• Injected into human as vaccine
• Induces both cell-mediated and humoral
immune response

31. Disadvantages of genetic vaccination
• Auto-immune responses
• Immunological unresponsiveness
• Carcinogenesis

32. Passive immunization
Indications:
• Immediate protection for immuno-competent
persons- recent exposure
• Bacterial infections
Disadvantages:
• Anaphylactic reactions
• Immune complex formation

33. Types of human immune globulins
• Standard immune globulin for intramuscular
use (IMIG)
• Standard immune globulin for intravenous use
(IVIG)
• Special human immunoglobulins

34. • Combined passive and active immunizations
• Immunization for foreign travellers

35. Adjuvants
• Some substances when mixed with an antigen
and injected into animals, the enhance the
immune responses to the antigen

36. Vaccines under trial
• Dengue virus
• Clostridium difficile
• Pseudomonas aeruginosa
• M. tuberculosis
• HIV
• Malaria

38. Passive immunization for non-infectious
diseases
• Passive immunization against Rh antigen
• Poisonous bites

40. Thank you