An Adverse event following immunization (AEFI) is any untoward medical occurrence or event which follows immunization and which does not necessarily have a causal relationship with the usage of the vaccine. The adverse event may be any unfavorable or unintended sign, abnormal laboratory finding, symptom or disease

1. Adverse Events
Following
Immunization
(AEFI)
Dr. Sonam Aggarwal
MD Community Medicine

2. Background

6. Contents
• Background
• Introduction
• What is Vaccine?
• Definition of AEFI
• Types of AEFIs
• Isolated & Cluster AEFI
• Case definition of various AEFIs
• AEFI Case Selection For Reporting
• Steps in AEFI investingation
• Contraindications to vaccines
• How to minimize AEFIs ?
• References

7. Introduction
• India is one of the largest manufacturers and exporters of vaccines in
the world.
• Apart from that, India runs one of the largest immunization programs
(Universal Immunization Program [UIP]) in the world for the
prevention of various vaccine-preventable diseases targeting
approximately 27 million newborns and 30 million pregnant women
every year.
• The detection of all possible AEs during the various phases of the
clinical trial is near impossible; hence, post marketing surveillance
(PMS) plays a major role in evaluating the safety of the vaccine.

8. • AEFI surveillance program was initiated by the Government of India
way back in 1986.
• The primary purpose of starting this program was detection of AEFI,
swift management, and appropriate action to prevent such events in
future.
• The Government of India published the first operational guideline for
AEFI in 2005 to strengthen and systematize the AE reporting system.
The Government of India brought revised AEFI guidelines in 2015.

10. What do you understand by term Vaccine.....
As per WHO,
-Vaccine is a biological preparation which functions by inducing the
immune system of the body to elicit an immune response to a particular
pathogen.
-Vaccines are usually regarded as innocuous, but like any other drug
products, they are not absolutely harmless, and sometimes AEs might
occur following their administration.

11. •No vaccine is 100% safe and without any risks
•Prepare parents for side effects

12. Definition of AEFI
• An Adverse event following immunization (AEFI) is any untoward
medical occurrence or event which follows immunization and which
does not necessarily have a causal relationship with the usage of the
vaccine.
• The adverse event may be any unfavorable or unintended sign,
abnormal laboratory finding, symptom or disease

13. Why “event” not “effect”?
• Event vs Effect (outcome of RI)
• Not desired -desired /expected
• Unwanted -wanted
• Eventful -uneventful
• Warrants actions -does not warrant actions
• More players -Less players
• (people gets involved) -(only beneficiary involved)

14. Types of AEFIs

16. Vaccine quality defect related reaction

17. Immunization error-related reaction(program
error)

20. Immunization anxiety-related reactions

21. Coincidental event
• An AEFI death following Pentavalent vaccine was reported on
11/4/2013 from Faridabad district of Haryana.
• A male child (DOB: 23 February, 2013) was vaccinated with the first
dose of the pentavalent vaccine at outreach session of Palla PHC in
Faridabad at 11:30 am on 10 April 2013. The child received the 4th
dose from a 10 dose vial and 8 children were vaccinated with the same
vial in that session.
• After the investigation of AEFI, event was classified into ‘coincidental’
category.

23. Vaccine Reactions

24. Two types of vaccine reactions-
Minor and Severe

27. AEFI Frequency Terminology

28. Severe event
• Severe is used to describe the
intensity of a specific event (as in
mild, moderate or severe)
• It includes the serious event
• The event itself, however, may be of
relatively minor medical
significance (e.g. Fever is a
common relatively minor medical
event, but according to its severity it
can be graded as mild fever or
moderate fever).
Severe and Serious reaction

29. Isolated & Cluster AEFI
• Isolated AEFI
This is solitary medical incident that takes place after immunisation,
causes concerns and is believed to be caused by immunisation.
• Cluster AEFI
A cluster is defined as two or more cases of the same or similar events,
which is related in time and has occurred within the same district or
geographical unit , or associated with same vaccine , same batch number
administered or same vaccinator

30. Case definition of various AEFIs

34. Signs of anaphylaxis

35. Drugs
• Inj. Adrénaline (1:1000) solution –
2 ampoules
• Inj. Hydrocortisone (100 mg) – 1
vial
• I/V fluids (Ringer lactate/Normal
Saline): 1 unit
• I/V fluids (5% Dextrose): 1 unit
• Tab Paracetamol (500 mg/125mg) -
10 tabs/Syp

36. Equipment
• Disposable Syringe (insulin type) having 0.01 ml graduations and 26G IM needle
– 2 sets
• Disposable Syringe (5 ml) and 24/26G IM needle – 2 sets
• Scalp vein set – 2 sets
• IV drip set: 1 set
• Cotton wool + adhesive tape : 1 each
• At hospital setting, Oxygen support and airway intubation facility should be
available

37. Difference between anaphylaxis and fainting

41. AEFI Case Selection For Reporting

44. Components of AEFI surveillance

45. Channels of reporting AEFIs:
1. Monthly routine reporting
2. Immediate serious AEFI reporting
• Case reporting form (CRF)
• Preliminary case Investigation form (PCIF)
• Final case Investigation form (FCIF)

52. Investigating AEFI clusters

53. Steps in an AEFI investigation
1. Confirm information in report
Actions: -
• Obtain patient's medical file (or other clinical record).
• Check details about patient and even from medical file and document
information.
• Identify any other cases that need to be included in the investigation.

54. 2. Investigate and collect data:
About the patient:
• Immunization history.
• Previous medical history, including prior history of similar reaction or
other allergies.
• Family history of similar events.

55. About the event:•
• History, clinical description, any relevant laboratory results about the
AEFI and diagnosis of the event.
• Treatment, whether hospitalized, and outcome.

56. About the suspected vaccine(s):
• Conditions under which the vaccine was shipped, its present storage
condition, state of vaccine vial monitor, and temperature record of
refrigerator.
• Storage of vaccine before it arrived at health facility, where it has
come from higher up the cold chain, vaccine monitor card.

57. About other people:
• Whether others received the same vaccine and developed illness.
• Whether others had similar illness (may need case definition) ; if so
exposure of cases of suspect vaccine(s).
• Investigate the local immunization service.

58. 3. Assess the service by:
Asking about:
• Vaccine storage (including open vials) , distribution , and disposal.
• Diluent storage and distribution.
• Reconstitution {process and time kept).
• Use and sterilization of syringes and needles.
• Details of training in immunization practice, supervision and
vaccinator(s).
• Number of immunizations greater than normal?

59. Observing the service in action:
• Refrigerator - what else is stored (note if similar containers stored next
to vaccine vials which could be confused); which vaccines/diluents
stored with other drugs; whether any vials have lost their label.
• Immunization procedures (reconstitution, drawing up vaccine,
injection technique, safety of needles and syringes; disposal of opened
vials) .
• Do any open vials look contaminated ?

60. 4. Formulate a working hypothesis:
• On the likely/possible cause(s) of the event.
5. Test working hypothesis
• Does case distribution match working hypothesis ?
• Occasionally, laboratory tests may help.

61. 6. Conclude investigation
• Reach a conclusion on the cause.
• Complete AEFI Investigation Form.
• Take corrective action, and recommend further action

62. • The focus of the investigation should be to confirm the working
hypothesis.
• Request laboratory testing only on a clear suspicion and not as routine,
and never before the working hypothesis has been formulated.
• The vaccine and diluent may be tested for sterility and chemical
composition; and the needles and syringe for sterility.
• Send unopened vaccine vials and matching diluent of the same batch
for testing.
• Send vaccine samples for testing to the National Control Laboratory
(NCL), Central Research Institute, Kasauli accompanied with a
completed Lab Requisition Form (LRF) along with a copy of the
available FIR/PIR.

63. Contraindications to vaccines
Vaccine Contraindication
All Anaphylactic reaction,
Current serious illness
Live vaccines (MMR, BCG, yellow
fever)
Pregnancy,
Radiation therapy
Yellow fever Egg allergy,
immunodeficiency
BCG Symptomatic HIV infection
Influenza, Yellow fever History of anaphylactic reaction following egg ingestion
Pertussis -containing Anaphylactic reaction to previous dose,
Evolving neurological disease

64. How to minimize AEFIs ?
• Use a separate site for each vaccine.
• Use auto-disable syringes for all immunization injections.
• Always check the label for the name of vaccine/diluent, expiry date and VVM.
• Shake the T series and Hep-B vaccine vials before drawing the dose.
• Reconstitute vaccines only with diluents supplied by the manufacturer for that
Vaccine
• Record the time of reconstitution of vaccine on the vial label.
• Use Measles and BCG vaccine within 4 hours of reconstitution.
• If they could not be used with in stipulated time then discard the reconstituted
vials..

65. • Never carry and use reconstituted vaccine from one session site to another.
• Do not store other drugs or substances in the ILR. These refrigerators are only
meant for vaccines.
• After injection, do not attempt to re-cap or bend the needle.
• Ask the beneficiaries to wait for half an hour after vaccination to observe for any
AEFI.
• Leave the list of children vaccinated in a session with the AWW/ASHA and
request them to be alert and report AEFIs.

66. References
1. Park K. Preventive and Social Medicine. 25th Edition. India: M/s
Banarsidas Bhanot Publishers; 2019.
2. Adverse event following immunization . Surveillance and response
operational guidelines . Ministry of health and family welfare .
Government of India; 2015.
3. WHO. Module -3 Vaccine Safety Basics, AEFI (Adverse Event
Following Immunization).
4. WHO. CIOMS (Council for International Organizations of Medical
Sciences); 2012.