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01 introduction to aefi
The document discusses the importance of immunization safety and adverse event following immunization (AEFI) surveillance. It outlines key elements of an effective immunization safety system including rapid notification, evaluation, and response to AEFI reports. The objectives of AEFI monitoring are to identify safety issues, estimate rates of serious AEFIs, and create awareness of vaccine risks. National regulatory authorities play an important role in vaccine safety surveillance.
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01 introduction to aefi
- 1. Introduction to Immunization Safety and AEFI Surveillance
- 2. OVERVIEW Immunization safetyas an emerging issue Need for immunization safety systems Critical elements of an immunization safety system (including the role of the National Regulatory Authority)
- 3. WHY IMMUNISATION SAFETY? Anti-immunisation lobby Changing Regulatory norms Vaccination campaign Mishandling rumours Unsafe injection Inadequate monitoring
- 4. UNSAFE INJECTIONS: ESTIMATED ANNUAL CONSEQUENCES > 20 billion injections annually 95% for curative purposes >50% unsafe 8-16 million HBV 2-4.5 million HCV 75 000-100000 HIV ? millions of injection site abscesses * Simonsen L et al. Bulletin of the World Health Organization , 1999 Unsafe injection
- 5. Key results ofthe Injection Safety Assessment INDCLEN – Govt. of India 2003 Unsafe injection practices 67.3% of unsafe injections overall 55% of non-sterile injections 73.9% of unsafe injections in immunization
- 6. VACCINATION CAMPAIGNS- SPECIAL ISSUES Apparent rise many doses over short period of time more vigilance/awareness Real rise from programmatic errors normal safe injection practices not observed new staff unfamiliar Adverse events generate criticism of campaign Vaccination campaign
- 7. CHANGING REGULATORY NORMS Old empirically defined procedure reliance on QC testing field studies done only for licensing New strictly defined procedure for consistency reliance on GMP rather than final product testing continuous safety and effectiveness surveillance Regulations are changing
- 8. FUNCTIONS OF A NATIONALREGULATORY AUTHORITY M arketing authorization and licensing P ost Marketing surveillance (PMS / AEFI monitoring) S ystem of lot release L aboratory access R egulatory inspections for GMPs O versight of clinical trials
- 9. THE ROLE OFTHE NATIONAL REGULATORY AUTHORITY What is the role of the NRA in vaccines safety surveillance? Who (within the NRA) should be responsible for vaccines safety surveillance? How and why should NRA and EPI work together?
- 10. A few terminologies… Adverse Events Following Immunization (AEFI) Adverse Drug Reaction (ADR) Post Marketing Surveillance (PMS) Adverse Events (AE) Severe Adverse Events (SAE)
- 11. OBJECTIVES OF MONITORINGAEFIs Identify urgent problems for investigation and action Detect signals for potential follow-up and research Estimate rates for serious AEFIs for comparison between products to determine risks and benefits of immunization to validate pre-licensure data Identify programmatic errors and batch problems Create awareness of risks among health professionals
- 12. KEY ELEMENTS OFAN EFFECTIVE IMMUNIZATION SAFETY SYSTEM Rapid notification of the basic information Rapid and effective evaluation of information Rapid and effective response/action Ensure appropriate outcome of action/response Adequate education and training of role players
- 13. OBJECTIVES OF THISWORKSHOP To provide us with importance of this activity in our country knowledge and skills to develop a AEFI surveillance system to detect report assess and respond to AEFIs (including communication) prevent Improve collaboration between NRA, NIP and others
- 14.
- 15. SIMILARITIES AND DIFFERENCES BETWEEN VACCINES AND MEDICINES
- 16. SIMILARITIES BETWEEN VACCINES AND MEDICINES Vaccines are also medicines Potential for adverse effects Multiple ingredients Potential for interaction with disease and other medicines Also need to comply with standards of safety, efficacy and quality
- 17. SPECIFIC ISSUES RELATED TO VACCINES Use on a large scale Use may be mandatory Public relations: we promote the product! service providers have the responsibility safety issues can be in conflict with programme close relationship with manufacturer
- 18. SPECIFIC ISSUES RELATEDTO VACCINES Procurement, storage and handling About 30 products compared with around 20 000 drugs Fewer manufacturers but more recipients Maintenance of the cold chain Imported vaccines - long distance transport
- 19. Promotion and Procurement:Vaccines vs Drugs Vaccine Public campaigns common Access/safety ++government procurement / program Collaboration UIP/Gov’t and manufacturers critical Drugs Public campaigns rare Access/safety variable ++private procurement / programs Drug manufacturers less relationship to gov’t
- 20. Storage and DistributionVaccines mainly in field, offices and clinics cold chain often critical biological product- lot variation, stability Drugs mainly in hospitals, clinics, pharmacies most a room temp chemical product
- 21. SPECIFIC ISSUES RELATEDTO VACCINES EFFICACY Given to healthy individuals difficult to detect lack of efficacy Perceived need depends on disease burden Herd immunity Goal: disease eradication Need vaccine distribution data (batch) Brand product specific manufacturing techniques (each product is different)
- 22. Efficacy: Vaccine vsDrugs Vaccines healthy prevention of disease large population most used in infants and children Drugs ill treat disease small population most used in adults
- 23. SPECIFIC ISSUES RELATEDTO VACCINES SAFETY Low public tolerance for adverse events Adverse drug reactions are more common Safety monitored by “promoters” Causality assessment difficult need special expertise Lot-by-lot surveillance needed
- 24. Safety Monitoring Vaccinesvs Drugs Need to ensure that vaccine safety monitoring and causality assessment utilizes system that meets vaccine specific needs Build on strengths of drug monitoring BUT modify and adapt to fit vaccines WHO
- 25. BARRIERS TO REPORTINGNot considering the event as related to immunization Not knowing about reporting system and process Lethargy - procrastination, lack of interest or time, inability to find report form Fear that the report will lead to personal consequences Guilt about having caused harm and being responsible for the event Uncertainty about reporting an event when not confident about the diagnosis
Editor's Notes
- #17 Vaccines are also medicines in that they are used to prevent certain diseases. As with all other medicines, vaccines may also be associated with risk of adverse reactions. Medicines,in general are much more likely to cause adverse reactions due to various reasons, however, the tolerance to such adverse effects appear to be lower for vaccines compared to medicines used for treating diseases. Both vaccines and medicines are composed of various ingredients all of which may contribute to an adverse drug reaction. Many drugs also need to have a cold chain maintained. As with all medicines, vaccines need to also go through the process of testing for safety, efficacy and quality and these properties need to be maintained throughout the life cycle of the medicine.
- #18 Specific issues related to vaccines: PROMOTION Vaccination is implemented to achieve public health goals- the aim is improving the health of populations, rather than individuals. The state has a vested interest in the immunization programme. The involvement of the state in the immunization programme may be perceived as a source of bias when safety issues are investigated. The immunization programme aims to increase vaccine coverage. An investigation into an adverse event may produce results that impact negatively on the goal of achieving complete vaccine coverage. (For example, the adverse event may be publicised and this will heighten the concerns of the public about issues of vaccine safety.) If the immunization programme is responsible for adverse event investigating, this may be perceived as a conflict of interests. The close relationship between the vaccine manufacturer and the immunization programme may also be perceived as a conflict of interests when adverse events are investigated.
- #19 PROCUREMENT, STORAGE AND HANDLING There are very few vaccines, in comparison with registered medicines. There are few manufacturers, and very few countries produce vaccines. Most countries use vaccines which are imported from elsewhere. Vaccines will often be transported for long distances to remote areas before they are administered. Maintenance of the cold chain is very important for certain vaccines.This is also the case for many medicines as well.
- #22 EFFICACY Efficacy of vaccines is measured at a community/population level. The goal of immunization is the prevention of infectious diseases and ultimately disease eradication. These endpoints of efficacy are usually only demonstrated once a vaccine is marketed and depends on the effective deployment of such vaccines to the population at risk of contracting the vaccine-preventable disease. They are usually given to healthy individuals, often to children as a preventative measure. The efficacy of a vaccine is therefore primarily seen on a public health level, where drops in prevalence of vaccine-preventable diseases can be measured. These benefits are usually less tangible to vaccinees and their care-givers (unless the vaccine-preventable disease is quite prevalent in the community). As vaccination programmes become increasingly successful at achieving the goals of disease eradication, the disease burden falls and the benefits of immunization become even less immediately apparent. For this reason, the public perception of efficacy changes over time. This differs from medicines used to treat medical conditions. In the latter case, patients and health care providers are usually able to directly perceive a benefit. Moreover, the benefit profile of a medicine usually remains fairly unchanged for the population being treated. At the time of registration of a vaccine, the efficacy of the vaccine is usually determined through the use of surrogate markers (such as antibody titres), Phase I, II and III trials (see Glossary) and from the experiences of countries where the vaccine is already used.
- #24 SAFETY We often vaccinate individuals who are healthy at the time of vaccination. This results in a low public tolerance for adverse events- the perception is that the individual was healthy “until the vaccine made them ill”. The safety of vaccines is often monitored within the immunization programme. If officials from the immunization programme are responsible for investigating adverse events related to administration of a vaccine, this may be perceived as a conflict of interests. There is a need for independent review of adverse events, separate from the immunization programme. Causality assessment requires a team of investigators, (including input from an immunologist ) It is important that reports of specific events, particularly programme errors, be solicited Additional notes With regards to safety monitoring of vaccines, there are several special considerations which could affect the type of immunization surveillance programme implemented. Due to the fact that vaccines are administered to well, healthy-looking infant and children, the level of tolerance for any adverse event is very much lower than with medicines used to treat medical conditions. As was discussed previously, the regulatory authority is usually the only organisation with the mandate to ensure the safety, efficacy and quality of vaccines. Vaccination programmes could be perceived as being promoters of vaccines and therefore not in an unbiased position to monitor the safety of vaccines. There are special challenges to assessing the causal association between a vaccine and an AEFI. These need to be considered and will be discussed in more detail in the talk on Causality. Special expertise including an immunological opinion is vital when assessing causality. Most AEFI programmes solicit specific reports such as local injection site reactions because they are also interested in programmatic errors rather than just pure vaccine reaction signals. Probably the greatest difference between vaccines and other medicines is the system of lot release. As with other medicines, the quality control of vaccines is used to establish whether the products are safe and potent. The quality control of vaccines usually relies on the control of starting materials, control of the production process, and final product. Traditionally the quality of vaccines used in immunization programmes is measured by potency testing in animal models. Many NRA’s employ a national control authority to conduct independent release of vaccines on a lot-by-lot basis. Very often the pharmacological action of vaccines and the adjuvants which are also present in the preparation are poorly understood, particularly by immunization staff. Moreover, there remain many unanswered questions about possible risks which have never been proven but are widely publicised. Some countries have resorted to providing a compensation plan for proven AEFIs. This is usually not attainable and feasible in developing countries with resource-poor immunization services.
- #26 Barriers to reporting Surveillance is dependent on the receipt of timely and accurate reports. Some of the barriers to reporting are listed above. These barriers to reporting can be overcome by: increasing awareness of the importance of reporting, and the system for reporting, and making it easy to report, especially in situations of uncertainty emphasising that investigations are about finding problems with the system and not blaming individuals giving positive feedback for reporting.