Control guideline for public health units

Public health priority: Routine.

Many adverse events following immunisation (AEFIs) are common and expected. For the purpose of this guideline, AEFIs (see Case Definition) include low level events, high level events and high-level events of significance. (See Appendix 1)

PHU response time: Respond to reportable low level AEFIs within 7 working days following notification. Respond to suspected high level AEFIs or adverse events of special interest (AESIs) within 3 days. Respond to suspected high level AEFIs of significance within 1 day. Follow up a suspected case as required.

Case management: Responsibility of the treating doctor. PHUs investigate using the Adverse Event Following Immunisation Form [PDF]. Advise on further immunisations if requested or facilitate specialist referrals as required.

Contact management: Nil.

Version Date Revised by Changes Approval
1.014/01/2021Immunisation BranchRevisionChief Health Officer
1.107/07/2022Immunisation BranchRevisionChief Health Officer
1.116/08/2022Immunisation BranchUpdate to Appendix 1 to expand reporting of AEFIs in all children <12 years that have been hospitalisedCommunicable Diseases Branch

Last updated: 27 April 2023

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1. Adverse events following immunisation

An adverse event following immunisation (AEFI) is any untoward medical occurrence that follows immunisation. It does not necessarily have a causal relationship with the vaccine.

An AEFI may be related to the vaccine itself or to its handling or administration.

The Australian Immunisation Handbook1 (online edition) provides information about the frequency, types and management of AEFIs such as anaphylaxis.

Serious adverse events

A serious adverse event following immunisation that includes any of the following2:

  • results in death
  • is life threatening
  • requires hospitalisation
  • results in persistent or significant disability or incapacity
  • results in a congenital anomaly/birth defect
  • does not fit in with the common reactions for that vaccine outlined in the Australian Immunisation Handbook1 (online edition).

Any clinical event that requires intervention to prevent one of the outcomes above may also be considered as serious2.

Detailed definitions of conditions classified as serious AEFIs are available in the Australian Immunisation Handbook1 (online edition).

Non-serious adverse event

A non-serious adverse event following immunisation is a common/expected adverse event known to be associated with the vaccine as described in the Australian Immunisation Handbook1(online edition) or product information and does not pose a potential risk to the health of the patient2. Any event that is considered by the immunisation provider or immunisation recipient to be significant, of concern, or affect confidence in future immunisations and may not fit in with the criteria for a serious AEFI can be reported.

2. Surveillance objectives

  • To monitor the safety of vaccines post-licensure to:
    • rapidly detect and respond to changes in the rates of known adverse events following immunisation (AEFIs), and
    • rapidly detect, investigate and respond to AEFIs of concern or significance
  • Contribute to national surveillance and signal detection of new and emerging AEFIs or AESIs by ensuring timely notification of AEFIs to the Therapeutic Goods Administration (TGA)
  • Support clinicians, including assistance in provision of advice for further immunisation doses, and
  • To maintain public confidence in vaccines and the National Immunisation Program (NIP).

3. Case definition

Suspected case

A suspected case is any adverse event, either serious or non-serious, that occurs after vaccination and is considered to be possibly related to that vaccination.

Factors to be considered in case identification

  • An AEFI can be coincidentally associated with immunisation without being caused by the vaccine or the immunisation process2. The notification of a suspected AEFI does not imply a causal association with vaccination.
  • The time interval from vaccination to onset may be relevant to causal determination but will depend on the adverse reaction2. As the time interval between immunisation and onset of the event may not always be accurate or well established, a time interval is not included in the case definition.
  • Notification is required by doctors and hospitals. Other clinicians are able to notify suspected AEFIs with the consent of the patient.
  • Non-serious AEFIs should also be carefully monitored because they may signal a potentially larger concern with the vaccine or immunisation process or may have an impact on the acceptability of immunisation in general2. Non-serious adverse events that have been reported to the PHU, should be entered into the Notifiable Conditions Information Management System (NCIMS).

4. Notification criteria and procedure

AEFIs are notifiable conditions under the NSW Public Health Act (2010). Notification is required by doctors and hospitals.

Suspected cases should be entered onto the NCIMS by the PHU.

Serious AEFIs and those reported to a school-based immunisation team on the day of vaccination should be reported directly to the NSW Health Immunisation Unit as well as being entered onto the NCIMS.

5. Managing single notifications

Investigation

Follow-up information of the notification will be obtained from the treating clinicians, medical records and/or patients/carers as appropriate.

Response times

The expected timeframe to report AEFIs is aligned with the level, likely causality and significance of the adverse event.

Suspected AEFI (see Case Definition) may be:

  • common and/or unlikely to be causally related to immunisation (low level),
  • uncommon and serious with potential relationship with recent immunisation (high level) or
  • uncommon and significant (high level of significance) with a likely causal link to immunisation, or likely significant media or community concern in relation to the relationship with recent immunisation.

Low level adverse events

Low level adverse events are adverse events which have a low level of concern in relation to immunisation. Low level adverse events include common and expected (non-serious) reactions for the vaccine (as outlined in the Australian Immunisation Handbook1 (online edition) or that are described in the product information), and other acute clinical events occurring in proximity to immunisation, but which are not considered as adverse events of special interest (AESI) and are not known to be causally linked to immunisation.

  • Any event that is considered by the notifying practitioner or immunisation recipient to be significant, of concern, or to affect confidence in future immunisations and which may not fit in with the criteria for a serious AEFI may be reported to the TGA. Low level reports will not normally require any further investigation by the PHU.
  • Low level events include (but are not limited to) acute clinical episodes such as deep vein thrombosis (DVT), cerebrovascular accident (CVA) or non-ST-elevation myocardial infarction (NSTEMI) occurring in proximity to immunisation, but which are not considered as adverse events of special interest (AESI) and are not known or suspected to be causally linked to immunisation.

Information in relation to low level events should be gathered and reported to the TGA within 7 working days.

Notification to the TGA should occur via the routine automated TGA reporting process in the NCIMS. Data transmitted to the TGA should be de-identified.

High level adverse events

High level adverse events are conditions which are known or suspected to be causally related to immunisation and have resulted in death and/or critical care admission and/or are of special interest (AESIs).

  • All high level AEFIs require discussion with the PHU Director. TGA notification of these high-level adverse events should occur within 3 days, unless the event is also significant, as determined by the PHU Director, in which case reporting may be required within 24 hours.
  • Notification of the initial case information will occur via the routine automated TGA reporting process in the NCIMS. Additional supporting documentation is provided to the TGA as a full, de-identified case file using secure file transfer and may also include the use of case report forms (available upon request from MoH-AEFI@health.nsw.gov.au) and case classification. Some of these cases (See Appendix 1) will also require reporting to HPNSW Immunisation Unit via email to MoH-AEFI@health.nsw.gov.au

High level adverse events of significance

  • High level adverse events of significance are those adverse events which have generated significant clinician and/or community concern in relation to the association with immunisation (e.g. where the death of a person has been directly attributed to immunisation), where there is media or other interest, or where a suspected serious AEFI in a child or younger person has resulted in death, critical care admission or significant impairment.
  • The PHU Director is responsible for reviewing high level adverse events which are of significance, and for ensuring they are reported to HP NSW Immunisation Unit as required.
  • Both the TGA and HPNSW Immunisation Unit should be notified within 24 hours of reporting. TGA reporting occurs as for high level adverse events. The PHU Director is responsible for ensuring notification to HPNSW, Immunisation Unit via email to MoH-AEFI@health.nsw.gov.au.

Data entry

  • Suspected high level cases of significance should be entered onto the notifiable diseases database within 1 working day following notification. The purpose of the initial report is to notify suspected serious AEFI to the TGA to enable timely detection of potential vaccine safety signals. A report must be made as quickly as possible, even if not all details have been obtained, so that an immediate decision can be made on the need for action and investigation. Updated information should be entered as soon as it becomes available.
  • Other suspected high level cases (but not of significance) should be entered onto the notifiable diseases database within 3 working days following notification.
  • Suspected low level cases should be entered onto the notifiable diseases database within 7 working days following notification.

Response procedure

Case investigation

For all cases collect information about the case using the Adverse Event Following Immunisation Form [PDF].

The response to a notification will normally be carried out in collaboration with the medical practitioner caring for the patient. But regardless of who does the follow-up, PHU staff should ensure that action has been taken to:

  • confirm the onset date and symptoms of the illness
    • seek the doctor's permission to contact the case or relevant caregiver
    • review case management including if appropriate follow up has been arranged for advice regarding future vaccinations, if required
    • confirm the date of resolution of symptoms and outcome of adverse reaction.

The Adverse Events of Special Interest (AESI) vaccine follow up form must also be completed for monitored events of special interest that have been reported in association with vaccination. The AESI vaccine follow up forms have been developed by the TGA with reference to the Brighton Collaboration Case Definitions and Guidelines for vaccine safety and include:

  • Anaphylaxis
  • Bell's Palsy
  • Encephalitis, Myelitis or Acute Disseminated Encephalomyelitis (ADEM)
  • Guillain-Barré Syndrome (GBS) including Miller Fisher Syndrome
  • Hypotonic-Hyporesponsive episode (HHE)
  • Multiple Sclerosis (MS) or Clinically Isolated Syndrome (CIS)
  • Neuritis
  • Optic Neuritis
  • Seizures
  • Serum Sickness
  • Vasculitis.

The AESI Vaccine follow up forms are available from the Immunisation Unit, Health Protection NSW.

See Appendix 1 for some examples of COVID-19 vaccine specific AEFIs/AESIs under each classification level.

Case management

The attending medical practitioner is responsible for treatment. The PHU should provide advice to the doctor regarding further immunisation if requested according to the recommendations of the latest Australian Immunisation Handbook1 (online edition).

Additional specialist advice and facilitation of future vaccination through specialist services may be obtained from the NSW Immunisation Specialist Service on 1800 679 477 or SCHN-NSWISS@health.nsw.gov.au.

Ensure feedback has been given to the immunisation provider using the AEFI standard response letters in the NCIMS.

TGA response procedure

Suspected cases of AEFI are reported to the TGA safety monitoring program daily via the NCIMS. The TGA enters all suspected AEFI to the TGA Adverse Events Management System (AEMS). Reports are then transferred to the publicly accessible Database of Adverse Event Notifications – medicines 90 days after they have been reported to AEMS.

The TGA may refer safety concerns to the Australian Committee on Medicines (ACM) for independent advice.

6. Vaccination failures

Vaccine failure is when a disease occurs in a person even though they have received the recommended number of vaccines.

Surveillance of vaccine failures is important to monitor overall vaccine effectiveness and to identify specific problems with vaccine manufacturing or program delivery, such as cold chain breaches.

Surveillance for vaccine failures occurs through disease surveillance processes rather than AEFI surveillance processes. Public Health Units should refer to the relevant NSW Control Guidelines for management of vaccine preventable disease notifications.

The vaccination failure AESI vaccine follow up form must be completed and submitted to the TGA safety monitoring program for assessment and surveillance and the Immunisation Unit, Health Protection NSW at MOH-AEFI@health.nsw.gov.au when a vaccine failure is identified.

7. Vaccine administration errors

Vaccination administration errors can occur as a result of errors in vaccine preparation, handling, storage or administration and can be associated with immunisation error-related reactions2. Identification and follow-up of vaccine administration errors can identify and correct immunisation error-related reactions in a timely manner.

It is the responsibility of the immunisation provider to manage vaccine administration errors and seek advice from the PHU if required. Vaccine administration errors resulting in a suspected adverse event following immunisation must be reported to the PHU and reported in the NCIMS.

Vaccination administration errors that may pose a safety risk to the patient, regardless of whether an adverse event following immunisation has occurred, must be reported to the TGA such as:

  • Inadvertent administration of a vaccine contraindicated in pregnancy or giving a live attenuated viral vaccine during pregnancy or shortly before pregnancy due to the potential risk to the fetus1, and
  • Inadvertent administration of zoster vaccine to an immunocompromised patient due to the risk of disseminated disease from the Oka vaccine virus1.

Vaccine administration errors that pose a safety risk to the patient must be reported to the PHU using the National Adverse Event Following Immunisation reporting form [PDF]. The notification form should be submitted to the TGA safety monitoring program and the Immunisation Unit, Health Protection NSW at MoH-AEFI@health.nsw.gov.au. An NCIMS entry is not required unless the vaccine administration error has resulted in an AEFI.

8. References and additional sources of information

Resources

References

  1. Australian Technical Advisory Group on Immunisation (ATAGI). Australian Immunisation Handbook (online edition), Australian Government Department of Health, Canberra, 2018.
  2. World Health Organisation (WHO).Global Manual on Surveillance of Adverse Events Following Immunization, World Health Organisation, Geneva, 2016.

9. Further information

Additional information and resources about vaccine safety and avoiding adverse events following immunisation are available on the NSW Health Immunisation program Adverse Events Following Immunisation (AEFI).

10. Appendices

Appendix 1

AEFI classification level and PHU priority and follow-up timeframe

AEFI classification level
EventPHU priority and follow-up timeframe
Low level AEFIIncludes common and expected adverse events following immunisation, as well as serious clinical events that occurred within 6 weeks of immunisation but are not known or suspected to be causally associated with immunisation, and are not AESIs, e.g. DVT, CVA or NSTEMI.Routine priority (within 7 days)
High level AEFIs/AESIs, but without sufficient significance to require urgent escalation to Ministry
Unusual clinical event following immunisation (but without significant clinician or community concern re relationship to immunisation), with critical care admission or major impairment.

Routine priority (within 3 days)

PHU Director to inform Ministry of Health.

TTS/VIPIT cases (refer to Appendix 3)For confirmed or probable cases - routine priority (within 3 days). PHU director to inform Ministry of Health if confirmed or probable TTS/VIPITS case (as per TGA criteria).
Myocarditis/pericarditis (refer to Appendix 4)Routine priority (within 3 days)

PHU director to inform Ministry of Health if case meets CDC criteria for confirmed and probable myocarditis, and confirmed pericarditis, and critical care admission or leads to death

Guillain-Barré syndrome (GBS) (refer to Appendix 5)Routine priority (within 3 days)

PHU director to inform the Ministry of Health if case meets Brighton Level 1, 2 or 3 and requires critical care admission or leads to death

AEFIs in children aged <12 years when the case has been hospitalised with a suspected vaccine-related complication (and temporal association)Routine priority (within 3 days)

PHU Director to inform Ministry of Health if case results in critical care admission, or major impairment.

Other adverse events of special interest (AESIs):
  • Idiopathic Thrombocytopenic Purpura
  • Post-Immunisation Multi-System Inflammatory Syndrome (MIS-V) or Paediatric Inflammatory syndrome post-immunisation (PIMS-TS)
  • Capillary Leak Syndrome
  • Hearing loss/Tinnitus
  • Toxic Epidermal Necrolysis

Routine priority (within 3 days)

PHU director to inform the Ministry of Health if case results in critical care admission or major impairment.

High level AEFI of significance Any death or acute life-threatening event (resulting in critical care admission or significant end-organ impairment) where the cause of death or the event might reasonably be suspected by the treating clinician, the Coroner (or in some circumstances the family) to be related to recent immunisation.

High priority (within 1 day)

PHU director to inform the Ministry of Health, Health Protection NSW, Immunisation Team.

Any AEFI where the PHU Director requests escalation to the Ministry as a high level AEFI of significanceHigh priority (within 1 day). PHU Director to review and inform Ministry of Health as above

Appendix 2

PHU management of AEFI

Flow chart of how public health units should manage an adverse event following immunisation. Text alternative follow image

Text alternative

  • Suspected AEFI notification (including PHREDSS referred by Ministry of Health)
  • Investigate and collate initial case information
  • Create and document case details in NCIMS - Refer to NSWISS clinical support as required
  • Assess and Triage as per PHU Guideline (escalate to PHU Director as required)
    • High level AEFI
      • PHU ensures initial AEFI case report is complete and mandatory NCIMS fields are completed
      • Automatic reporting (via NCIMS) of initial case information
      • Gather additional information
      • PHU Director to consider if a referral to HPNSW is required
        • High level AEFI of significance
          • Refer to HP NSW
          • HP NSW provide to expert panel chair for consideration to convene the panel. HP NSW to convene panel where determined appropriate
          • PHU Director or NSWISS delegate to chair expert panel meeting. PHU to present case to expert panel
          • PHU follow up expert panel recommendations
          • Update NCIMS and send updated case notes and supporting documents to the TGA via secure file transfer
          • TGA request for additional information – YES
            • Gather additional information
            • PHU Director to consider if a referral to HPNSW is required
            • Update NCIMS and send updated case notes and supporting documents to the TGA via secure file transfer
      • Update NCIMS and send updated case notes and supporting documents to the TGA via secure file transfer
    • Low level reportable AEFI
      • PHU ensures AEFI case report is complete and mandatory NCIMS fields are completed
      • PHU authorises AEFI case report in NCIMS for automatic reporting to TGA
      • TGA request for additional information – YES
        • Gather additional information
        • PHU Director to consider if a referral to HPNSW is required
        • Update NCIMS and send updated case notes and supporting documents to the TGA via secure file transfer

Appendix 3

Suspected Thrombosis with Thrombocytopenia (TTS) classification tool

TGA classifications for possible, probable, and confirmed TTS cases.

  • Possible:
    • Objective evidence of thrombosis (radiological, surgical or autopsy)
      and
    • Platelets <150x10^9/L without history of heparin exposure
      and
    • D-dimer normal, <2xULN (ULN=0.5) or unknown
  • Probable:
    • Objective evidence of thrombosis (radiological, surgical or autopsy)
      and
    • Platelets <150x10^9/L without history of heparin exposure
      and
    • D-dimer ≥2xULN (ULN=0.5)

    • Remain as probable even if PF4 antibodies are negative or unknown.

  • Confirmed:
    • Objective evidence of thrombosis (radiological, surgical or autopsy)
      and
    • Platelets <150x10^9/L without history of heparin exposure
      and
    • D-dimer ≥2xULN (ULN=0.5)
      and
    • PF4 antibodies are positive
      or
    • if case is confirmed by the TGA requested EPR or VSIG

Appendix 4

Pericarditis and Myocarditis classification tool

ConditionCDC case definition
Myocarditis - Confirmed case
  • Presence of ≥ 1 new or worsening of the following clinical symptoms:
    • chest pain, pressure, or discomfort
    • dyspnea, shortness of breath or pain with breathing
    • palpitations
    • syncope

    and
  • ≥ 1 new finding of
    • Histopathologic confirmation of myocarditis
    • cMRI findings consistent with Myocarditis

    and
  • no other identifiable cause of symptoms and findings.
Myocarditis - Probable case
  • Presence of ≥ 1 new or worsening of the following clinical symptoms:
    • chest pain, pressure, or discomfort
    • dyspnea, shortness of breath or pain with breathing
    • palpitations
    • syncope

    and
  • ≥ 1 new finding of
    • elevated troponin(>ULN)
    • abnormal ECG or rhythm monitoring findings consistent myocarditis
    • cMRI findings consistent with Myocarditis

    and
  • no other identifiable cause of symptoms and findings.
Pericarditis

Presence of ≥ 2 new or worsening of the following clinical features:

  • acute chest pain
  • pericardial rub on exam
  • new ST-elevation or PR-depression on ECG
  • new or worsening pericardial effusion on echocardiogram or MRI

Appendix 5

Decision tree algorithm for GBS: level of diagnostic certainty (adapted from Brighton Collaboration)

Flow chart of decision tree algorithm, text alternative follows image

Text alternative:

  • Does the patient meet all four of?
    1. bilateral and flaccid paralysis of limbs
    2. decreased or absent deep tendon reflexes in affected limbs
    3. monophasic illness and interval between onset and nadir is 12 hours-28 days and then a clinical plateau
    4. No alternative diagnosis for weakness
  • If yes - are Nerve Conduction Studies and CSF (protein >0.5 g/L and WCC<50) both consistent with GBS?
    • If yes - Level 1 GBS
    • If no - Are either NCS or CSF consistent with GBS?
      • If yes - Level 2 GBS
      • If no – Level 3 GBS
  • If no to ≥ 1 criterion – Level 5 – Not a case of GBS.
  • If Insufficient information to choose yes for all criteria, or no for≥ 1 criterion - Level 4: reported as GBS, but insufficient evidence to meet any level of case definition.


Current as at: Thursday 27 April 2023
Contact page owner: Immunisation