ADVERSE EVENT FOLLOWING IMMUNISATION

Last updated: 13 September 2004

Reason for surveillance

• To detect changes in the rates of known adverse events following immunisation (AEFIs)

• To detect AEFIs which were previously undocumented.

Case definition

Suspected case
A person with any condition that is serious or unexpected that occurs any time after he or she received a vaccination and is considered by the doctor to be possibly related to that vaccination. Such conditions may including:

• Abscess

• Acute flaccid paralysis

• Allergic reaction

• Anaphylaxis

• Arthralgia

• Arthritis

• Brachial neuritis

• Death

• Disseminated BCG

• Encephalopathy

• Encephalitis

• Extensive limb swelling

• Fever - over 40.5°C

• Guillain-Barre Syndrome (GBS)

• Hypotonic - hyporesponsive episode (shock, collapse)

• Local reaction (severe)

• Lymphadenitis (includes suppurative lymphadenitis)

• Meningitis - diagnosis must be made by physician

• Nodule

• Orchitis

• Osteitis

• Osteomyelitis

• Parotitis

• Rash (severe or unusual)

• Screaming (persistent)

• Seizure

• Sepsis

• Subacute sclerosing panencephalitis

• Thrombocytopenia

• Toxic-shock syndrome

• Vaccine associated paralytic poliomyelitis

• Other severe or unusual events

Factors to be considered in case identification
The inclusion of a condition in the list of suspected AEFIs does not imply a causal association with vaccination, since the condition can occur coincidentally.

Medical practitioners or other health professionals are free to report any AEFI that concerns them, even if the AEFI does not fit into any of the above categories.

Notification criteria and procedure

Suspected cases are to be notified by:

• Medical practitioners and hospital CEOs on diagnosis (ideal reporting by routine mail).

AEFIs reported to a school-based immunisation team on the day of vaccination are reported directly to the NSW Health Immunisation Unit using a separate surveillance system, and are not entered onto NDD. However, AEFIs associated with school-based immunisation that are reported after the team has left the school should be entered onto NDD.

Managing single notifications

Response time

Investigation
Within 3 working days of notification of a suspected case begin follow-up investigation using the Adverse Event Following Immunisation Form.
Contact the doctor caring for the patient to obtain followup information 60 days after the onset date of the AEFI.

AEFIs reported to a school-based immunisation team on the day of vaccination are managed by the school-based team directly, without PHU involvement. However, AEFIs associated with school-based immunisation that are reported after the team has left the school should be investigated by the PHU.

Data entry
Within 7 working days of notification enter suspected cases on NDD. Update information obtained from the 60 day follow up or from ADRAC's review within 5 working days of receipt.

AEFIs reported to a school-based immunisation team on the day of vaccination should not be entered onto NDD. However, AEFIs associated with school-based immunisation that are reported after the team has left the school should be entered onto NDD.

Response procedure
The response to a notification will normally be carried out in collaboration with the case's health carers. 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

• Find out if the case or relevant care-giver has been told what the diagnosis is before interviewing them

• Seek the doctor's permission to contact the case or relevant care-giver

• Review case management.

Case management
For all cases (except for those reported to the school based immunisation teams) seek information about the case using the Adverse Event Following Immunisation Form initially and 60 days after the onset date.

Provide advise to the doctor regarding further immunisation if requested according to the recommendations of the latest Australian Immunisation Handbook. Specialist advice may be required.

Suspected cases of AEFI are forwarded by the Immunisation Unit to ADRAC for review. The Immunisation Unit will inform the Public Health Unit of the outcome of Adverse Drug Reaction Advisory Committee's review.