Published: 15 January 2025
Safety Information
Spontaneous reports: Seasonal influenza vaccination 2023
This page provides information on the number of adverse events following immunisation (AEFI) reports for influenza vaccines reported to the New Zealand Pharmacovigilance Database in 2023.
- New database
- Influenza vaccines administered and number of AEFI reports
- Serious reports
- Reports by ethnicity and age
- AEFIs reported
- Who is reporting?
- Definitions
- More information
New database
In September 2023, the collection, processing (coding) and storage of adverse reaction reports (including AEFIs) moved from the Centre for Adverse Reactions Monitoring (CARM) to a new database run by Medsafe (the New Zealand Pharmacovigilance Database). The CARM experts now focus on the valuable role of medical assessment of non-routine reports.
The change to the new database means that the AEFI data for 2023 cannot be directly compared to previous years.
The AEFI data shown below was extracted from the New Zealand Pharmacovigilance Database on 9 December 2024. The data was correct at the time of extraction but may change over time due to receipt of additional information.
Influenza vaccines administered and number of AEFI reports
There were four approved and available quadrivalent vaccines in 2023, two of which were funded for eligible people:
- Afluria Quad for children and adults aged from 3 years (funded)
- Afluria Quad Junior for children aged under 3 years, ie, 6–35 months (funded)
- Fluad Quad for adults aged 65 years or older
- Fluquadri for children and adults 6 months of age and older.
Table 1 shows the number of AEFI reports received and the number of influenza vaccine doses administered in 2023.
Table 1: AEFI reports for influenza vaccines, vaccine doses administered and estimated reporting rate, 2023
| 2023 | |
|---|---|
| Number of reportsa | 262 |
| Influenza vaccine doses administeredb | 1,278,600 |
| Estimated reporting rate per 100,000 doses administered | 20.5 |
- Source: AEFI reports for influenza vaccines reported to the New Zealand Pharmacovigilance Database. Data extracted 9 December 2024.
- Source: Aotearoa Immunisation Register. Data extracted 31 October 2024.
Serious reports
A serious AEFI is defined as any reaction that results in death or is life-threatening, causes or prolongs hospitalisation, results in persistent or significant disability/incapacity, is a congenital abnormality or is a medically important event.
A report will be coded as serious in the database if the reporter considers that one or more of the suspected reaction(s) were serious. Medsafe or CARM may also upgrade a report to serious if we disagree with the reporter, but we don’t downgrade a serious report to non-serious.
Of the 262 influenza vaccine AEFI reports received, 70 (26.7%) were coded as serious in the database (Table 2).
Table 2: AEFI reports for influenza vaccines, number (No.) and percentage (%) of non-serious and serious reports, 2023
| Report type | No. | % |
|---|---|---|
| Non-serious reports | 192 | 73.3% |
| Serious reports | 70 | 26.7% |
| Total | 262 | 100.0% |
Reports by ethnicity and age
Reports by ethnicity and age are shown in Tables 3 and 4, respectively.
Table 3: AEFI reports for influenza vaccines by ethnicity, 2023
| Ethnicity | 2023 |
|---|---|
| Māori | 6 |
| Pacific peoples | 4 |
| Asian | 20 |
| European or Other | 162 |
| Unknown/not reported | 70 |
| Total | 262 |
Note:
- Ethnicity is based on prioritised ethnicity, which means each person is only counted against a single ethnicity category. When a person has multiple ethnicities recorded, then the prioritised ethnicity is ranked in the order of 1) Māori 2) Pacific Peoples 3) Asian 4) Other. For example, if a person is recorded as their ethnicities being both Māori and Pacific Peoples, their prioritised ethnicity will be Māori, ie, they will not be counted in the Pacific Peoples group.
Table 4: AEFI reports for influenza vaccines by age band, 2023
| Age band | 2023 |
|---|---|
| Under 3 years | 5 |
| 3 to 11 years | 11 |
| 12 to 17 years | 3 |
| 18 to 44 years | 53 |
| 45 to 64 years | 45 |
| 65 to 74 years | 30 |
| 75 years and older | 24 |
| Unknown/not reported | 91 |
| Total | 262 |
AEFIs reported
The most frequently reported AEFIs in 2023 were headache, fatigue and dizziness (Table 5).
Table 5: Top 10 most frequently reported AEFIs for influenza vaccines, 2023
| AEFI | No. of reports |
|---|---|
| Headache | 45 |
| Fatigue | 36 |
| Dizziness | 30 |
| Pain in extremity (arm or leg pain) | 27 |
| Pyrexia (fever) | 26 |
| Nausea | 25 |
| Injection site erythema (redness) | 21 |
| Injection site pain | 19 |
| Pain | 19 |
| Injection site swelling | 18 |
Who is reporting?
Anyone can submit a report. Table 6 shows the number of reports by reporter type received for 2023. Nurses (99) and members of the public (85) submitted the most reports.
Table 6: Number of reports received by reporter type, 2023
| Reporter type | 2023 |
|---|---|
| Nurse | 99 |
| Public | 85 |
| Pharmacist | 37 |
| General practitioner | 35 |
| Other healthcare professional | 6 |
| Total | 262 |
Notes:
- Public includes consumers and non-healthcare professionals.
- Pharmaceutical companies receive reports from a variety of reporters (eg, nurses, public, GPs) and then submit the reports to the New Zealand Pharmacovigilance Database. These reports are coded as per the original reporter, not the pharmaceutical company.
Definitions
- Adverse event following immunisation (AEFI)
- An AEFI is an untoward medical event which follows immunisation and does not necessarily have a causal relationship with the administration of the vaccine. The adverse event may be an unfavourable or unintended sign, abnormal laboratory finding, symptom or disease.
- Serious adverse events following immunisation
- A serious AEFI is one where the reporter
considered that the event:
- was medically important
- required hospitalisation or prolonged an existing hospitalisation
- caused persistent or significant disability or incapacity
- was life threatening
- caused a congenital anomaly/birth defect
- resulted in death.
It is possible for different people to have experienced the same event but for the report to be serious for one person and non-serious for another person.
More information
Medsafe
All medicines and vaccines can cause side effects. The known side effects for influenza vaccines are listed in the data sheets and consumer medicine information (CMI).
See also:
- How Medsafe monitors vaccine safety
- Report a suspected adverse reaction
- Suspected Medicine Adverse Reaction Search (SMARS)
Health New Zealand | Te Whatu Ora
