Published: 26 May 2021
Archived: 21 August 2024

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COVID-19 Archive

Adverse events following immunisation with COVID-19 vaccines: Safety Report #8 – 24 April 2021

• Introduction
• Adverse events following immunisation (AEFI) reported
• Definitions
• More information

Introduction

This page provides information on the number of adverse events following immunisation (AEFI) reports received for COVID-19 vaccines.

The national roll-out of COVID-19 vaccines commenced on 20 February 2021. The vaccine currently available in New Zealand is Pfizer-BioNTech (Comirnaty). All medicines can cause side effects, the known side effects for Comirnaty are listed in the data sheet and consumer medicine information.

Suspected AEFI to COVID-19 vaccines are reported to the Centre for Adverse Reactions Monitoring (CARM). The Ministry of Health (through Medsafe) contracts the collection of this information to CARM, based at the University of Otago in Dunedin. Medsafe is closely monitoring the AEFI reported from the use of the COVID-19 vaccine. Find out more about vaccine safety monitoring.

Adverse events following immunisation (AEFI) reported

The information below includes:

• AEFI reports received and vaccine doses administered
• AEFI reports by prioritised ethnicity and vaccine dose
• AEFI reports by age band and vaccine dose
• the top 10 most frequently reported AEFIs by vaccine dose.

AEFI reports received and vaccine doses administered, up to and including 24 April 2021

There were 403 non-serious and 19 serious reports this week. Twelve of the serious reports were for allergic reactions and 3 were for reactogenicity reactions (flu-like symptoms). The remaining serious reports were: myocarditis (1 report; see the New safety signal section below), stroke (2 reports), impaired consciousness (1 report).

Anaphylaxis

Of the 12 reports of allergic reactions this week, there were 3 reports where the reporter indicated suspected anaphylaxis. CARM assessed these cases against the Brighton Collaboration case definition for anaphylaxis. One case was possible Brighton anaphylaxis level 3, one case was possible Brighton anaphylaxis level 2 and the last case was possible Brighton anaphylaxis level 1.

Anaphylaxis is a rare adverse event that can occur with any vaccine. People giving vaccines must have medical treatment for anaphylaxis on hand, and must keep people under observation for at least 20 minutes so that anaphylaxis can be managed, if it happens.

New safety signal: myocarditis

There was one serious report of myocarditis this week. Medsafe is currently reviewing this signal and we will provide further information once the review is completed.

AEFI reports received by prioritised ethnicity and vaccine dose, up to and including 24 April 2021

Ethnicitya	Dose 1	Dose 2	Dose unknownb	Total
Māori	83	31	0	114
Pacific Peoples	72	41	0	113
Asian	244	92	0	336
European/Other	751	337	0	1,088
Unknown	16	17	2	35
Total	1,166	518	2	1,686

Notes:

1. The prioritised ethnicity classification system allocates each person to a single ethnic group, based on the ethnic groups they identify with. Where people identify with more than one group, they are assigned in this order of priority: Māori, Pacific Peoples, Asian, and European/Other. So, if a person identifies as being Māori and New Zealand European, the person is counted as Māori. See Ethnicity Data Protocols for further information.
2. There were 35 AEFI reports where the person’s ethnicity was not reported, including 2 reports where both the ethnicity and vaccine dose number were not reported. Ethnicity and dose number are not required for an AEFI report to be considered valid. See ‘Valid report’ in the Definitions section below.

AEFI reports received by age band and vaccine dose, up to and including 24 April 2021

Age	Dose 1	Dose 2	Dose unknowna	Total
10 - 19 years	37	4	0	41
20 - 29 years	268	125	0	393
30 - 39 years	262	123	0	385
40 - 49 years	217	118	0	335
50 - 59 years	222	103	0	325
60 - 69 years	118	39	0	157
70 - 79 years	30	3	0	33
80+ years	12	1	0	13
Unknown	0	2	2	4
Total	1,166	518	2	1,686

Note:

1. There were 4 AEFI reports where the person’s age was not reported, including 2 reports where both the age and vaccine dose number were not reported. Age and dose number are not required for an AEFI report to be considered valid. See ‘Valid report’ in the Definitions section below.

Top 10 most frequently reported AEFIs, any dose, up to and including 24 April 2021

Reaction	Number
Headache	508
Dizziness	435
Nausea	340
Injection site pain	314
Lethargy	238
Flu-like illness	174
Fever	158
Muscle pain	140
Musculoskeletal pain	97
Joint pain	86

Top 10 most frequently reported AEFIs, dose 1 only, up to and including 24 April 2021

Reaction	Number
Dizziness	343
Headache	297
Nausea	211
Injection site pain	184
Lethargy	114
Flu-like illness	80
Fever	65
Muscle pain	57
Syncopea	57
Numbness	43

Note:

1. Syncope: fainting

Top 10 most frequently reported AEFIs, dose 2 only, up to and including 24 April 2021

Reaction	Number
Headache	211
Injection site pain	130
Nausea	129
Lethargy	124
Flu-like illness	94
Fever	93
Dizziness	92
Muscle pain	83
Musculoskeletal pain	68
Joint pain	54

Please note that one adverse event report, which represents one person, may report on more than one symptom. Reports are sent to CARM if the reporter suspects that the vaccine may have caused the event. This does not necessarily mean that the vaccine did cause the event.

The number of reports can be influenced by how many people are being vaccinated, media attention, the nature of the events (eg, how painful the vaccination was), and other factors which vary over time. Not everyone who has an adverse reaction reports it, and some people may report AEFIs after each vaccination. The information here shows the number of reports not the number of people who experienced an AEFI.

The information is limited by the information provided in the report and may change over time due to quality control procedures and/or receipt of additional information. Non-valid reports are not included in the data.

Medsafe and CARM thank everyone who has contributed to the monitoring of COVID-19 vaccines. Please continue to report any adverse events following immunisation.

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 event following immunisation

An AEFI is considered serious if it:

• is a medically important event or reaction
• requires hospitalisation or prolongs an existing hospitalisation
• causes persistent or significant disability or incapacity
• is life threatening
• causes a congenital anomaly/birth defect
• results 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.

Safety signal

Information on a new or known adverse event that may be caused by the vaccine and requires further investigation. Safety signals can be detected from a wide range of sources such as CARM reports, clinical studies and scientific literature.

Valid report

There are only four requirements for a valid AEFI report:

1. one patient identifier (eg, name, initials, gender, date of birth, age)
2. suspect medicine(s)
3. suspected reaction(s)
4. reporter details.

These four requirements are the minimum requirements. However, including more information in the report helps Medsafe to investigate the reaction more quickly. Reporting is easiest online.

More information

See the data sheets and consumer medicine information for the expected reactions for approved COVID-19 vaccines.

COVID-19 Vaccine Safety Monitoring Process

View Ministry of Health COVID-19 vaccine data