Immunization schedules_2.pptx for medical

Microbiology

1. Immunization Schedules Linda Siachalinga Bpharm -UNZA Msc SPharm-Yeungnam University

2. Topic Objectives Describe the concept of immunology Explain the EPI Describe the immunization guidelines and schedules Outline contraindications to immunizations Explain cold chain and Logistics Evaluate immunization programme Report effectively and keep records

3. Introduction The fundamental goal of immunization is to prepare the immune system to defend the host against disease by intentionally exposing the body to all or part of an infectious agent in an effort to confer long-term protective immunity against future infection and to protect the most vulnerable individuals against disease Immunity protects the body against infectious diseases mainly through the production of “ antibodies ” or “ immunoglobulins ,” once the immune system has been stimulated by exposure to antigens

4. Introduction Cont ….. For a vaccine to be efficacious and reduce the incidence of vaccine preventable diseases, it must elicit the production of high-quality antibodies against the pathogen responsible for disease Certain vaccines are able to generate an immunologic memory similar to that generated by a natural infection , which often confers lifelong protection, whereas other vaccines may require boosters over time to maintain immunity I mmune response is largely dependent upon the properties of the antigen used to develop the vaccine and on the route of administration

5. Components Involved in Immunity There are two types of components that are involved in immunity. These are: Non-specific component or innate immunity Specific component or adaptive immunity

6. Natura l Acquired Specific Defenses Immunity Active Immunity Passive Immunity Following clinical infection Following sub-clinical infection Following vaccination Transfer of maternal antibody (placenta) Transfer of maternal antibody (milk) Following administration of immunoglobulin/antisera

7. Immunizing agents antisera immunuglobulins vaccines Immunizing Agents

8. Immunoglobulin There are 5 major classes: IgM, IgA, IgG, IgE , IgD . Two types of immunoglobulin preparations are available for passive immunization: Normal human immunoglobulin Specific (hyper-immune) human immunoglobulin The immunoglobulin M (IgM) is the primary immunoglobulin generated after immunization, quickly followed by the IgG To demonstrate the immunogenicity of a vaccine, serum anti-vaccine (or antigenic marker) IgG antibodies are measured Antisera and Antitoxins These are materials prepared in animals or non human sources

9. Vaccination Vaccination is a method of giving antigen to stimulate the immune response through active immunization. A vaccine is an immuno-biological substance designed to produce specific protection against a given disease . A vaccine is “antigenic” but not “pathogenic

10. Types of Vaccines Live vaccines Attenuated live vaccines Inactivated (killed vaccines) Toxoids Polysaccharide and polypeptide (cellular fraction of infecting organisms) vaccines

11. Live and Live Attenuated Vaccines Live vaccines are made from live infectious agents without any amendment Must replicate to induce an immunological response Live attenuated ”, meaning that the microbe in the vaccine is alive but has been weakened (attenuated) through serial passage n cultures, or produced through genetic technology They have lost their capacity to induce full-blown disease but retain their immunogenicity Live attenuated vaccines should not be administered to persons with suppressed immune response due to: Leukemia and lymphoma Other malignancies Receiving corticosteroids and anti-metabolic agents Radiation pregnancy

12. Inactivated Vaccines Organisms are killed or inactivated by heat or chemicals but remain antigenic. They are usually safe but less effective than live attenuated vaccines (can not multiply ) The only absolute contraindication to their administration is a severe local or general reaction to a previous dose Recently developed non-live vaccines do not contain antigen but employ RNA or DNA to instruct the recipient’s own cellular mechanism to generate antigenic material

13. Toxoids They are prepared by detoxifying the toxins produced by some bacteria rendering them antigenic but not pathogenic Adjuvant (added things) is used to increase the potency of vaccine The antibodies produces in the body as a consequence of toxoid administration neutralize the toxic material produced during infection rather than act upon the organism itself In general toxoids are highly efficacious and safe immunizing agents

14. Polysaccharide and polypeptide They are prepared from extracted cellular fractions. Examples: Meningococcal vaccine from the polysaccharide antigen of the cell wall Pneumococcal vaccine from the polysaccharide contained in the capsule of the organism Hepatitis B vaccine from polypeptide Their efficacy and safety appear to be high

15. Expanded Program on Immunization The Expanded Program on Immunization (EPI) is a WHO program with the goal to make vaccines available to all children throughout the world WHO initiated the EPI program in May 1974 with the objective to vaccinate children throughout the world In 1984 , the WHO established a standardized vaccination schedule for the original EPI vaccines: Bacillus Calmette-Guérin (BCG), diphtheria-tetanus-pertussis (DPT), oral polio vaccine (OPV), ,measles, Pneumococcal Conjugate vaccines(PCV) and Rota virus vaccine(RVV).

16. Goals for EPI To ensure full immunization of children under one year of age in every district to globally eradicate poliomyelitis To reduce maternal and neonatal tetanus to an incidence rate of less than one case per 1,000 births by 2005, to cut in half the number of measles-related deaths that occurred in 1999 To extend all new vaccine and preventive health interventions to children in all districts in the world.

17. Immunization in Zambia Zambia has been conducting immunization services since inception of the expanded program on immunization in 1974 High vaccine coverage has been achieved over the years Subsequently this has resulted in the reduction of reported cases and deaths due to the vaccine preventable diseases

18. Immunization in Zambia Zambia adopted the goal of Universal Child Immunisation (UCI), meaning that all children aged zero to five years must receive; BCG Measles OPV and DPT- HepB -Hib rotavaccine PCV Now IPV

19. Immunization in Zambia The priority is for all children to receive all doses before their first birthday A fully immunised child is one who has received BCG, OPV, DPT- HepB -Hib and measles by the age of 11 months All children under five years would become eligible for supplemental immunisation activities

20. Goal of Immunization Program Protect more people by use of safe and effective vaccines Accelerate the reduction of morbidity and mortality from vaccine preventable diseases Strengthen immunisation programme financing and sustain the introduction of additional vaccines s trengthen EPI Disease Surveillance in the context of overall improvement of national health information system Integrate EPI with other interventions in the context of strengthening the Health System

21. Target Groups for Immunization Program Children under five years School aged children Pregnant women Women of child bearing age (15 – 49yrs) Special at risk groups (e.g. Travellers )

22. Immunization Guidelines and Schedule Optimal response to a vaccine depends on multiple factors, including the type of vaccine, age of the recipient, and immune status of the recipient Recommendations for the age at which vaccines are administered are influenced by: age-specific risks for disease age-specific risks for complications age-specific responses to vaccination potential interference with the immune response by passively transferred maternal antibodies Vaccines are recommended for members of the youngest age group at risk for experiencing the disease for which efficacy and safety have been demonstrated.

23. Schedule for Childhood Vaccination in Zambia

24. Schedule for Childhood Vaccination in Zambia

25. Route and Dose of Vaccine

26. Route and Dose of Vaccine

27. Schedule for Childhood Vaccination in Zambia The schedule is divided into four (4) strategies, that is A, B, C and D Strategy A This is done at the at the health facility which has a refrigerator and provides MCH services. Multiple vaccines such as BCG, OPV, DPT + Hib + Hepb and measles can be given at the same visit

28. Schedule for Childhood Vaccination in Zambia The schedule is divided into four (4) strategies, that is A, B, C and D Strategy A This is done at the at the health facility which has a refrigerator and provides MCH services. Multiple vaccines such as BCG, OPV, DPT + Hib + Hepb and measles can be given at the same visit All eligible children should be given immunization at every contact with a health facility if they come for under 5 services All children with symptomatic HIV/AIDS should not be given BCG and yellow fever but the other vaccines can be given (WHO/UNICEF recommendations )

29. Schedule for Childhood Vaccination in Zambia Strategy B This strategy provides health services to the communities living outside a 12 km radius from the health facility It is carried out either on foot, bicycle, motor cycle or vehicle The schedule for outreach should be planned in such a way that the target population is covered within the set time-frame using the available resources All the vaccines administered in Strategy A apply in this strategy as well to all the eligible children.

30. Schedule for Childhood Vaccination in Zambia Strategy C-School Health Services In school health services, only susceptible children are immunized against measles if they were not earlier immunized The eligible children in this aspect are the grade ones (School entry ) BCG is given to those without a scar from the initial dose A booster dose of Tetanus Toxoid is given

31. Schedule for Childhood Vaccination in Zambia Strategy C-School Health Services

32. Schedule for Childhood Vaccination in Zambia Strategy D-TT Immunization Schedule for Women of Child-bearing Age

33. Catch up vaccination and simultaneous administration of vaccines What would be the appropriate action to take: A child who is seen for the first time later than the scheduled age of immunization e.g 5 months ? A child who did not receive the first dose of MR Vaccine at 9 months?

34. Exception for Immunization Medical basis Disease or take medicine that weakens immune system severe allergy to a vaccine or an ingredient in it Serious reaction to a vaccine in the past Religious basis Evidence that the family belongs to a religious group that objects to vaccines maybe required Few religions object to vaccines, including Christian Scientists and some faith healing groups Philosophical Exemption is based on parents' personal beliefs about vaccines Mostly concerns are about vaccine safety

35. Vaccine Potency and Safety Vaccine Vial Monitor (VVM ) T he vaccine vial monitor (VVM) is a temperature monitoring device that is attached to the vaccine ampoule, dropper or vial and helps to indicate if the vial can be used or not The vaccine can only be used when : The expiry date has not been reached The VVM has not changed its colour The vaccine vial can be withdrawn or discarded when: The expiry date is reached regardless of the colour of the VVM The VVM changes colour regardless of the expiry date

36. Importance of Vaccine Vial Monitors Prevents delivery and administration of heat damaged vaccines Reduces vaccine wastage Indicates cold chain problems Saves as tool to manage vaccine stocks

37. The Shake Test Shake tests are used to test the potency of freeze-sensitive vaccine by exposure to temperature below c A positive shake test is the formation of granular particles which show up in the liquid upon shaking the vaccine after the vaccine was frozen and then thawed

38. Adverse Events Following Immunization (AEFI) These are vaccine induced reactions which are usually mild and temporary In rare instances, reactions following immunization can be severe AEFI should be monitored by all providers of Immunization services AEFI should be investigated and efforts made to determine its cause Consideration when determining AEFI Programmatic errors in handling, reconstitution or administering the vaccine Nature of the vaccine or individual response to the vaccine. Coincidence Unknown cause

39. Cold Chain and Logistics Cold Chain is a temperature-controlled system used to maintain potency of a vaccine from the manufacturer to the time it is given to the target consumer

40. Equipment for Cold Chain Thermometer is used for monitoring temperature The ice-packs are used for keeping the vaccine cool in cold boxes or vaccine carriers thereby maintaining their potency Vaccine carriers are small boxes used for the collection of small quantities of vaccines for a health Centre or for an outreach session Cold Boxes :These are much larger than vaccine carriers. They are used for collection of large quantities of vaccines for health facilities or district storage

41. Storage Temperature for Vaccines Most vaccines can be stored at temperatures between 2 ◦C to 8 ◦ C Some can be stored between -15 ◦C to -25 ◦C At Provincial and District level TT and DPT between 0 and 8 ◦C Measles , MMR, OPV, BCG between -15 and -25 ◦C At Health Centre Level All vaccines can be stored at 0 and 8 ◦C Storage is limited to 1 month Check and record temperatures everyday in the morning and evening

42. Freezing sensitive Heat sensitive Least sensitive Least sensitive Hep B Hib DT Td TT OPV Measles MMR BCG Hib

43. Importance of Maintaining a Cold Chain Maintaining the potency of vaccines is important for several reasons It ensure that an effective, safe and good product is being used V accines are thermo-sensitive hence a proper cold chain is required to maintain potency Vaccine failures caused by administration of compromised vaccine may result in the re-emergence preventable disease

44. Importance of Maintaining a Cold Chain cont … Maintaining the potency of vaccines is important for several reasons It ensure that an effective, safe and good product is being used V accines are thermo-sensitive hence a proper cold chain is required to maintain potency Vaccine failures caused by administration of compromised vaccine may result in the re-emergence preventable disease

45. Storage of vaccine The optimum temperature for vaccines is between +2°C and + 8°C For frozen vaccines the optimum temperature is - 15°C to -35°C In addition, protection from light is a necessary condition for heat sensitive vaccine The allowable timeframes for the storage of vaccines at different levels are : 6-12 months -Regional Level (national) 3 months -Provincial Level 1-3 months District Level 1 month -main health centers Not more than 5days- Health centers using transport boxes

46. Storage of vaccine Most sensitive to heat: Freezer (-15 to -25 degrees C) OPV Measles MMR BCG Hib Note: never freeze vaccine diluent

47. Storage of vaccine Freezing sensitive (ref . +2 to +8 degrees Celsius) DPT Hepatitis B TT PCV Rota IPV HPV

48. Storage of vaccine Proper arrangement of vaccines and/or labeling of vaccines expiry date are done to identify those near to expire vaccines Use those that will expire first, mark “ X” FEFO -“first expiry and first out ” -vaccine is practiced to assure that all vaccines are utilized before the expiry date

49. Vaccine Forecasting Vaccine forecasting is the first step in ensuring adequate immunization supplies and is the foundation of Vaccine Security . The accuracy of the forecast is important underestimating the requirements results in vaccine shortages, overestimating results in excess stock The goal of vaccine forecasting is to estimate the quantity of goods and financial needs necessary to conduct immunization programs

50. Vaccine Forecasting The value of the forecast depends on the accuracy - taking into consideration the type of vaccine, the presentation (vial size), the quantity and the timing of delivery of the vaccine . Accurate forecasting of vaccine needs is essential to ensure the right amount of vaccine and injection equipment as well as safety boxes are available to vaccinate all eligible clients within a given Catchment or geographical area Furthermore, vaccine forecasting ensures an adequate buffer stock to meet the unexpected demands.

51. Ordering Vaccines Vaccine ordering is done according to the following: Target population method Consumption method Number of immunization sessions per month

52. Consideration for Ordering Wastage rate This rate, expressed as a percentage, is the proportion of vaccine that is wasted due to a variety of reasons, to that which is appropriately used Wastage Factor This factor is a mathematical expression used to account for the correct amount needed for an immunisation session taking into account the existing wastage rate Buffer stock The idea of buffer stock is to ensure that you have sufficient stock incase of unexpected shortage. Shortages may arise due to outbreaks, poor vaccine forecasting and disruption in supplies.

53. Determining the wastage factor Example If wastage rate for DPT + Hib is 25% then the wastage rate is 100 divided by 100 minus 25 = 1.3 WF=100/ 100 / (100-25) = 1.3 Therefore, if you have to vaccinate 50 infants with DPT-Hib, your vaccine requirement is; 50 infants x 3 doses x 1.33 (wastage factor) = 195 doses

54. Forecasting U sing Target Population Data needed Target population Vaccine wastage rate Immunisation coverage target Vial size Number of doses per child

55. Forecasting Using Target Population Formula for target population Target population ( Ptarg ) Target coverage ( Tvc ) No. of doses ( Ndoses ) Wastage factor ( Fwaste ) Formula: Total number of doses= Ptarg X Tvc X Ndose X Fwaste Note: Wastage Factor = 100/ (100 –WR)

56. Consumption method Stock at the beginning of the year (Sini) Quantity received during the year ( Qrec ) Stock at the end of the year (Send) Quantity wasted during the year ( Qwaste ) Formula: Total number of doses= Sini + Qrec – (Send + Qwaste )

57. Evaluation of EPI programme When evaluating the immunization programme , the following must be assessed Disease incidence Susceptibility Vaccine Coverage Adverse events and vaccine safety

58. Evaluation of EPI programme Record keeping and reporting is important and critical This is so because it helps to plan for future immunization by identifying the gaps and making recommendations on how to meet them The tools used for record keeping and reporting are; Tally sheets Under five register Childrens card Reporting books Plot charts like the immunization coverage plot charts for each vaccine

59. Evaluation of EPI programme The reporting will help to ; Estimate the size of the total population your programme serves Calculate the target population say for the measles vaccine Estimate the expected coverage for the next period Calculate the number of doses given, vaccines spoiled or wasted Estimate the frequency of supply Add a reserve stock of the total

60. Question What is herd immunity? Understand Factors used to determine herd immunity How to calculate the percentage of people that need to be vaccinated to attain herd immunity