1. VACCINOLOGY

2. History Concept of Vaccination and Types of Vaccines General Principles Principles according to type Practices Present status of Vaccines [update]

3. HISTORY Lady Mary Montagu was first to introduced variolation in Great Britain- 1718

4. Edward Jenner  First to publish and test immunity by challenge with smallpox.  1796, inoculated a person, 5 years later vaccination became popular.  Invented smallpox vaccine

5. Dawn of Immunological Science 1875-1910 Louis Pasteur 1881 anthrax vaccine was run and in 1882 85000 sheep was immunized. Introduced use of vaccinia virus Invented rabies vaccine

6. Robert Koch His discovery of Vibrio cholerae, killed whole-cell bacterial vaccines were introduced in 1896

7. Early Bacterial Vaccines, toxins, and toxoids [1910-1930] Koch’s isolation of tubercle bacillus, ushered the search for a vaccine for tuberculosis. 13 years after bacille Calmette-Guerin (BCG) was invented Calmette [left] Guerin [right]

8. World War I gave increased opportunity for the killed whole-cell bacterial vaccines to make, especially in the case of typhoid. 1920s a killed bacterial vaccine was used fairly widely against Bordetella pertussis. 1923 Glenny and Hopkins discovered that formalin treatment of diphtheria toxin could render it harmless while preserving its immunogenic potential

9. Early Viral Vaccines: Yellow Fever and Influenza [1930-1950] Max Theiler’s safe and effective live attenuated yellow fever vaccine 17D, hails from this period. First-generation killed whole-virus influenza vaccines and vaccines against typhus and Japanese B encephalitis vaccines also hails from this period.

10. The tissue Culture Revolution: Poliomyelitis, Measles, Mumps and Rubella [1950-1970] On April 12 1955, the 10 th anniversary of the death of Franklin Roosevelt, the famous polio victim, a press conference in the University of Michigan revealed to the world that Jonas Salk’s formalin-treated whole virus vaccine provided protection between 1955 and 1961, 300 million does were administered and incidence of polio declined dramatically

11. 11 In 1965 Salk’s vaccine was replaced by Albert Sabin’s vaccine because 149 cases of polio occurred due to faulty production technique Edmondston strain of measles vaccines Enders’ original was first introduced in 1963 but was still risky 1964 more attenuated Moraten an Schwartz derivatives of the original Enders strain was introduced. 1967 mumps vaccine was invented 1968 a live attenuated rubella vaccine was invented 1969 a combined measles-mumps-rubella vaccine was introduced and licensed in 1971

12. Dawn of the Molecular Era: Hepatitis B., Pneumococcus, and Haemophilus influenzae B. [1970-1990] Hepatitis B vaccine, use of the surface antigen of the hepatitis B virus represented a new degree of purity of a single protein as a vaccine. First vaccine manufactured through recombinant DNA technology. First time vaccine was introduced as a expensive vaccine for special risk groups like doctors, nurses etc. Ushered in the new era where genetic engineering approaches have become the norm in vaccine research and development.

13. Molecular vaccines of a different character were the subunit capsular polysaccharide vaccines against Streptococcus pneumoniae, Neisseria meningitidis and Haemophilus influenzae B were licensed in 1970s and early 1980s. Various Hib conjugates were licensed in the late 1980s effectively bringing us to the modern era

14. Small pox eradication By 1953 North and Central America had beaten it 1953 Europe 1975 eliminated in Asia Last occurring case recorded in Merca Somalia on October 26, 1977 December 9, 1979, the Global Commission certified that eradication was achieved. An estimation of U.S. $300 million over 11 year period was spent.

15. Concept of vaccination and Types of Vaccine To stimulate the immune response without subjecting an individual to the risk of actual infection. Primarily to prevent infection Strengthen an immune response that is inadequate, particularly in chronic recurrent diseases Types of vaccines live attenuated vaccine Inactivated vaccine Polysaccharide vaccines Recombinant vaccines

16. General principles Another way to produce active immunity is by vaccination. Vaccines interact with the immune system and often produce an immune response similar to that produced by the natural infection do not subject the recipient to the disease and its potential complications. Vaccines produce immunologic memory similar to that acquired by having the natural disease. Many factors may influence the immune response to vaccination.These include the presence of maternal antibody, nature and dose of antigen, route of administration, and the presence of adjuvants

17. Principles according to type. 1. Live Attenuated Vaccines Live vaccines are derived from “wild,” or disease-causing, virus or bacteria. These wild viruses or bacteria are attenuated, or weakened, in a laboratory, usually by repeated culturing In order to produce an immune response, live attenuated vaccines must replicate (grow) in the vaccinated person. A relatively small dose of virus or bacteria is given, which replicates in the body and creates enough virus to stimulate an immune response. The immune response to a live attenuated vaccine is virtually identical to that produced by a natural infection

18. 2. Inactivated vaccines These vaccines are produced by growing the bacteria or virus in culture media then inactivating it with heat and/or chemicals (usually in formalin). Inactivated vaccines are not alive and cannot replicate. The entire dose of antigen is administered in the injection. These vaccines cannot cause disease from infection, even in an immunodeficient person In general, the first dose does not produce protective immunity, but only “primes” the immune system. A protective immune response develops after the second or third dose the immune response to an inactivated vaccine is mostly humoral. Little or no cellular immunity results.

19. 3. Polysaccharide vaccines are a unique type of inactivated subunit vaccine composed of long chains of sugar molecules that make up the surface capsule of certain bacteria The immune response to a pure polysaccharide vaccine is typically T-cell independent, which means that these vaccines are able to stimulate B- cells without the assistance of T-helper cells.

20. Practices Simultaneous administration of antibody (in the form of immune globulin) and vaccine is introduced as Post exposure prophylaxis of certain diseases, such as hepatitis B,rabies, and tetanus. If the live vaccine is given first, the antibody is given at least 2 weeks after. Oral typhoid is not licensed for children less than 6 years of age Live parenteral (injected) vaccines (MMR, varicella, and yellow fever) that are not administered simultaneously are separated by at least 4 weeks If the antibody is given before a dose of varicella vaccine, Antibody is allowed to degrade before giving the vaccine to reduce the chance of interference by the antibody Simultaneous administration of all vaccines for which a child is eligible is very important in childhood vaccination programs, it increases the probability that a child will be fully immunized at the appropriate age

21. Vaccine Update Under-used vaccines –Haemophilus influenzae type b By end of 2002, 100% of countries were using the vaccine in routine immunization programme –Hepatitis B By 2001 only 75% of countries have this vaccine in their infant immunization routine –Yellow fever Avialable since 1937 but its used has been a public health failure. Over the past 2 decades there were 12 times as many cases as during the previous 2 decades –Rubella Universal rubella immunization has not been recommended by WHO to date

22. Vaccine Update Eradication of vaccine preventable diseases –Polio Polio-free –1994 Americas –2000 western pacific –2002 Europe –Measles Still in progress In 2001 over 100 million children have been vaccinated in Africa alone –Neonatal tetanus 104 out of 106 developing countries have succeeded. WHO, UNICEF and UNFPA set a joint effort to eliminate this disease by the end of 2005

23. Vaccine Update Priority new vaccines –HIV/AIDS No effective vaccine at present –Malaria No effective vaccine at present –Tuberculosis Limited protection, immunity is believed to wane during adolescence –Pneumococcal disease –New vaccine was licenced in 2000 United states. but not applicable foe developing countries due a different bacterial strain. –Meningococcal disease New licensed in 1999 for a serogroup C disease –Rotavirus diarrhoea Development and testing going on

24. Vaccine Update Neglected vaccines –Cholera Safe and effective are available, but oral vaccine are under consideration for public health use in emergency situation to immunize population at high risk. –Shigella dysentery It is likely to be 5-10 years before a vaccine is introduced. –Dengue 2 vaccines are undergoing trials 1 being developed in the United States the other in Thailand –Japanese encephalitis A vaccine has been developed and tested in china but not yet suitable for global use. –Leishmaniasis Development remains fragmented and lacks support –Schistosomiasis Two leading candidates have been successful in animals 1 has advanced to human trials.

25. Vaccine Update Other vaccines –Cervical cancer The most advanced candidates in development are recombinant protein vaccine against HPV types 16 and 18. Which could prevent 50-60% of cervical cancer. –Respiratory syncytial virus Current vaccine efforts are directed toward the development of a vaccine that incorporates the 2 RSV serotypes [A and B ] –Herpes simplex virus type 2 –Enterotoxigenic Escherichia coli [ETEC] A new vaccine delivery technology- transcutaneous immunization involving the use of patch to deliver vaccine through skin, has been successfully tested in humans for ETEC vaccine