Understanding Vaccines & Their Use in Host Defense Mechanisms

1. The structure and the use of vaccinesEwa Majda-StanisławskaDepartment of Infectious Diseases and HepatologyMedical University of Lodz

2. Host defence mechanisms

4. Antibodies used for passive protection: human immunoglobulin • prepared from sera of healthy adults • containing various antibodies • administered in severe infections, especially in people with impaired immunity

5. Administration of specific antibodies • + Straightforward protection, the most effective way of treatment of some infectious diseases • - 1. Short-lasting, about 6 weeks, 2. Decreasing immunological response to simultaneously administered antigens in vaccines 3. Possibility of transmission of some infectious agents

7. Administration of specific antibodies • For treatment of: diphteria, tetanus, botulism, snake bite, newborn of mother with varicella • Active + passive (serum + vaccine): - rabies - tetanus - Exposure for HBV of non-immune person

8. Antibodies used for passive protection Specific immunoglobulinaimed to protectfromcertaindisease • Gamma globulin prepared from sera of people lately cured of infectious disease or from volunteers who were hyperimmunised (vaccinated several times) • Examples immunoglobulin anti-HBV (HBIG) human immunoglobulin against rabies (HRIG) human immunoglobulin against varicella and zoster (HVIG)

9. Antibodies used for passive protection ANTITOXIN • ANTITOXIN is specific immunoglobulin • ANTITOXIN contains specific antibodies neutralising toxin (bacterial poison). It is obtained by administration of small amounts of poison to animals (horses) or human volunteers - obtaining serum pobierając, that is later processed and purified

10. Examples of the use of antitoxins • ANTITOXIN against botulism, diphteria, tetanus • ANTYVENIN against poisonous snake bite

11. ANATOXIN • ANATOXIN (Toxoid) is bacterial toxin (poison) which after laboratory processing is lacking its poisoning effect, but still has its antigenic properties. Anatoxins are used in various vaccines: diphetria, tetanus vaccine

13. Diseasesthatchildhoodvaccinesprevent • Diphteria • Tetanus DTP • Pertussis • Haemophilusinfluenzaetype B (HiB) • Poliomyelitis (IPV or OPV) • Measles • Mumps MMR • Rubella • Hepatitis B

14. Diseasesthatchildhoodvaccinesprevent • Hepatitis A • HumanPapillomaVirus (HPV) • Meningitis (Men ABCWY or Men B) • Rotavirus • Varicella

17. Number of doses your child needs • 4 doses of diphtheria, tetanus & pertussisvaccine • 4 doses of Hibvaccine • 4 doses of pneumococcalvaccine • 3 doses of polio vaccine • 2 doses of hepatitis A vaccine • 3 doses of hepatitis B vaccine • 1 dose of measles, mumps & rubellavaccine • 2-3 doses of rotavirusvaccine (depending on thebrand) • 1 dose of varicellavaccine • 1 or 2 annualdoses of influenza vaccine (number of dosesdepends on influenza vaccinehistory)

18. Vaccine is a biological product containing substances that are able to induce immunological response leading to long-term protection against specific infectious disease

19. Aims of vaccinations • Individual protection against infectious disease • Elimination of a pathogen from human environment

20. Elimination of an organism from human environment = ERADICATION • possible for pathogens with sole human reservoir, no transmission to animals • vaccination of about 90% of non-immune population at the same time • successful eradication of variola (1979 r) • WHO programme - „The world without polio” -planned to fulfil in the year 2000

21. Vaccination of certain % of population at the same time to achieveherdimmunity

22. Smallpox - Variola vera

23. Edward Jenner - the first attempt to use of a virus of cowpox to achieve immunity for smallpox

24. Smallpox (Variola vera) • The first infectious disease to be protected from by vaccination: Edward Jenner 1796 • The first infectious disease that was eradicated with the use of universal vaccination - (the last natural case was noted in 26.10.1977 in Somalia) • The last laboratory infection - 1978, Medical University in Birmingham • Certificate of global eradication of smallpox 9.12.1979

25. The features of ideal vaccine • One dose • Long-lasting or even permanent protection in 100% of vaccinated people • No side-effects • Cheap price

26. Administration of vaccines • Intramuscular or subcutaneous injection • Oral (OPV, rotavirus) • Intranasal (historical – smallpox)

27. Classification of vaccines according to the number of antigens • Monovalent- containing 1 antigen of the pathogen for example hepatitis B vaccine • Polivalent - protecting from several serotypes of the same pathogen for example polio vaccine (type 1, 2 i 3); pneumococcal vaccine, influenza.

28. Classification of vaccines according to the number diseases they protect from • Single pathogen (hepatitis B) • Combined (several species in one injection eg diphetria-tetanus-pertussis (DTP), measles + mumps + rubella (MMR)

29. Classification of vaccines according to their structure 1. Live micro-organisms, able to multiply in human body a. Natural (cowpox) b. Attenuated (BCG, MMR, varicella) 2. Complete pathogens, unableto replicate A. Whole-cell (pertussis) b. Inactivated viruses (HepatitisA)

30. Attempts to protect from tuberculosis - vaccination with bovine strain

31. Louis Pasteur - the use of artificial media to culture bacteria (attenuation)

32. Attenuation is the process of deprivation of pathogens’ virulence factors while antigens stimulating immunity are untouched

33. Live Attenuated Vaccines • Attenuated (weakened) form of the "wild" virus or bacterium • Must replicate to be effective • Immune response similar to natural infection • Usually produce immunity with one dose* *except those administered orally

34. Live Attenuated Vaccines • Viral measles, mumps,rubella, varicella/zoster yellow fever, rotavirus • Bacterial BCG, oral typhoid

35. Inactivated Vaccines • Viral polio, hepatitis A, rabies, influenza* • Bacterial pertussis*, typhoid* cholera*, plague*

36. Bacteria that cause purulent meningoencephalitis Streptococcus pneumoniae Capsulated bacteria Haemophilus influenzae Neisseria meningitidis

37. Neisseria meningitidis - encapsulated bacteria

38. Conjugate Vaccines Pneumococcal Meningococcal Men C Men B Men ACWY Haemophilusinfluenzaetype b

39. Vaccines suggested by WHO • DTP • Measles • Poliomyelitis