COVID-19 vaccine weekly safety report - 21-10-2021

Published

21 October 2021

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Vaccination against COVID-19 is the most effective way to reduce deaths and severe illness from infection. Millions of people have now received COVID-19 vaccines under the most intense safety monitoring ever conducted in Australia.

Three COVID-19 vaccines are currently in use in Australia – Comirnaty (Pfizer), Spikevax (Moderna) and Vaxzevria (AstraZeneca). To be registered for use, these vaccines must meet the TGA’s high standards for quality, safety and effectiveness.

Like all medicines, COVID-19 vaccines may have some side effects (also known as adverse events). The overwhelming majority of these are mild and resolve within a few days. More serious side effects can occur after vaccination but are very rare.

The TGA closely monitors reports of suspected side effects to the COVID-19 vaccines and provides regular updates on vaccine safety in this report. Find out how the TGA identifies and responds to a safety concern.

Importantly, suspected adverse events reported to the TGA are often not caused by the vaccines. Learn more about causality and the TGA’s COVID-19 vaccine safety monitoring and reporting activities.

Report a suspected side effect.

Summary

The protective benefits of vaccination against COVID-19 far outweigh the potential risks of vaccination.
To 17 October 2021, approximately 32.7 million vaccine doses have been given in Australia – 18.3 million first doses and 14.4 million second doses.
The most frequently reported side effects suspected to be associated with the vaccines reflect what was seen in the clinical trials. They include injection-site reactions such as a sore arm, and more general symptoms such as headache, muscle pain, fever and chills.
We are carefully monitoring and reviewing reports of suspected myocarditis and/or pericarditis following the Comirnaty (Pfizer) and Spikevax (Moderna) vaccines, particularly in younger age groups.
For Comirnaty (Pfizer), to 17 October 2021, we have received 312 reports of suspected myocarditis alone or in combination with pericarditis, and an additional 836 reports of suspected pericarditis alone. In the same period for Spikevax (Moderna), we have received 5 reports of suspected myocarditis and 28 reports of suspected pericarditis. These events can occur due to other causes, including common viral infections, so it is expected that not all cases are related to vaccination. Our analysis of cases likely to be myocarditis suggests reporting is more common in teenage boys after the second dose of the Pfizer vaccine (5.2 cases per 100,000 doses) compared to the rest of the general population after a first or second dose (0.8 per 100,000 doses). This has also been observed in other countries.
We are also closely monitoring rare reports of blood clots with low blood platelets (also called thrombosis with thrombocytopenia syndrome or TTS) linked to Vaxzevria (AstraZeneca). In the last week, 4 additional reports of blood clots and low blood platelets have been assessed as probable TTS, bringing the total number of cases to 156.

Reported side effects for COVID-19 vaccines

Gathering reports of adverse events following immunisation (AEFI) is just the first step in determining whether the effect is related to the vaccine and whether a significant safety issue is involved. Learn more about how the TGA identifies and responds to safety issues.

In the general population, the most frequently reported side effects suspected to be associated with the vaccines include injection-site reactions such as a sore arm, and more general symptoms such as headache, muscle and joint pain, and fever and chills.

The TGA is closely monitoring reports in people aged under 18 years as vaccination continues in this age group. We know from the Comirnaty (Pfizer) and Spikevax (Moderna) clinical trials that the most common adverse reactions in adolescents are similar to those in older people and include injection-site pain, fatigue and headache. Most of these side effects were mild and resolved within a day or two. For both vaccines, they were more common after the second vaccine dose than the first.

To 17 October 2021, we have received 1040 reports in individuals under 18 years old after vaccination with Comirnaty (Pfizer) and Spikevax (Moderna). The most commonly reported reactions are dizziness, fainting (syncope) and feeling faint (pre-syncope), nausea and chest pain.

To help us assess the safety of the COVID-19 vaccines, we encourage people to report suspected side effects even if it is not certain that the vaccine caused them. Anyone can report a suspected side effect including members of the public, nurses, pharmacists, doctors, health authorities and pharmaceutical companies. A report can be made directly to the TGA, through a health professional, or by calling the NPS MedicineWise Adverse Medicine Events phone line for consumers. Reporting can be anonymous if preferred. For more information click Report a suspected side effect.

Total adverse event reports to 17 October 2021

2.2
Reporting rate per 1000 doses
72011
Total AEFI reports received
32653925
Total doses administered
38901
Total reports for Vaxzevria
32281
Total reports for Comirnaty
498
Total reports for Spikevax

To 17 October 2021, the total number of adverse event reports received where the brand of the COVID-19 vaccine was not specified was 386.

Reports of death in people who have been vaccinated

Large scale vaccination means that coincidentally some people will experience a new illness or die within a few days or weeks of vaccination.

The TGA reviews all deaths reported in people who have been vaccinated. As the number of vaccinated people has increased, so has reporting of fatal events with a coincidental association with vaccination. This does not indicate a link between vaccination and the fatalities reported. Review of individual reports and patterns of reporting does not suggest the vaccines played a role in these deaths.

Since the beginning of the vaccine rollout to 17 October 2021, approximately 32.7 million doses of COVID-19 vaccines have been given. So far, the TGA has found 9 reports of death that were linked to immunisation from 612 reports received and reviewed. The overwhelming majority of deaths reported to the TGA following vaccination occurred in people aged 65 years and older. The deaths linked to immunisation occurred after the first dose of Vaxzevria (AstraZeneca) – 8 were TTS cases and one was a case of immune thrombocytopenia (ITP).

Myocarditis and pericarditis with mRNA vaccines

Myocarditis (inflammation of the heart) and pericarditis (inflammation of the membrane around the heart) are rare effects on the heart that typically occur within 10 days of vaccination with the mRNA vaccines Comirnaty (Pfizer) and Spikevax (Moderna). Cases are usually transient and resolve following treatment and rest.

Myocarditis is seen much more commonly in people who become infected with COVID-19 than in people who are vaccinated. The Australian Technical Advisory Group on Immunisation (ATAGI) continues to emphasise that the protective benefits of the mRNA vaccines far outweigh the rare risk of these side effects in all eligible age groups.

We encourage people to seek medical attention if they experience symptoms that could suggest myocarditis or pericarditis. This includes chest pain, palpitations (irregular heartbeat), fainting or shortness of breath, particularly if they occur within 1–5 days of vaccination.

Initial tests for those presenting with symptoms include ECG, troponin and chest X-ray. Brief guidance on the initial assessment of children and adolescents with symptoms has been published by the Paediatric Research in Emergency Departments International Collaborative (PREDICT) network(link is external).

ATAGI advises that people who develop myocarditis or pericarditis attributed to their first dose of Comirnaty (Pfizer) should defer further doses of an mRNA COVID-19 vaccine and discuss this with their treating doctor.

Details of Australian cases to date

Our analysis of Australian data indicates there is a higher-than-expected number of cases of myocarditis in vaccinated compared to unvaccinated individuals for Comirnaty (Pfizer). This is similar to findings from other drug regulators overseas.

To 17 October 2021, we have received 312 reports of suspected myocarditis alone or in combination with pericarditis, with 43 of these reports in adolescents (12-17 years-old). We have also received 836 reports of suspected pericarditis alone, with 47 of these reports in adolescents. In the same period for Spikevax (Moderna), we have received 5 reports of suspected myocarditis and 28 reports of suspected pericarditis. Two of the pericarditis cases were in children – both boys aged 12 and 16 years. These events can occur due to other causes, including common viral infections, so it is expected that not all cases are related to vaccination.

As we have only limited reports for the Spikevax (Moderna) vaccine, our analysis focuses on data for the Comirnaty (Pfizer) vaccine. We have reviewed all reports of suspected myocarditis for Comirnaty (Pfizer) against an internationally accepted criteria to confirm whether or not they are myocarditis. This assessment does not determine whether cases have been caused by vaccination.

Cases considered to be highly likely to be myocarditis, based on strong clinical evidence, are classified as level 1. We are less certain that cases classified as level 2 or 3 represent myocarditis. These have less information and may be supported only by the patient’s symptoms and limited test results or the treating doctor’s view. Of the 312 suspected cases:

175 were classified as likely to be myocarditis (20 were level 1, 109 were level 2 and 46 reports were level 3)
58 were deemed unlikely to be myocarditis
78 could not be classified because they did not contain enough information

Table 1. Total cases classified as likely to be myocarditis (levels 1-3) following Comirnaty to 17 October 2021
Age (years)	All doses				Second doses
Age (years)		Total cases		Rate* per 100,000 doses		Total cases		Rate* per 100,000 doses
Male		Female	Male	Female	Male	Female	Male	Female
≤19†	28	5	3.5	0.6	14	4	5.2	1.5
20-29	46	18	2.3	0.8	30	12	2.9	1.0
30-39	19	11	0.9	0.5	7	4	0.8	0.4
40-49	14	15	0.6	0.6	11	11	1.0	1.0
50-59	5	7	0.3	0.4	1	3	0.1	0.4
60-69	0	2	0.0	0.5	0	0	0.0	0.0
70+	0	0	0.0	0.0	0	0	0.0	0.0
Age unknown	2	1			1	0
All ages‡	114	59	1.4	0.6	64	34	1.6	0.8

*The rate includes cases of myocarditis that occurred after vaccination but may not be vaccine-related. The number of younger people vaccinated is still relatively low in Australia, so estimated reporting rates are based on limited data.

†The youngest case classified as ‘likely myocarditis’ to date was 12 years old.

‡Two cases did not specify patient sex and have not been included in the table above.

Most of the patients with myocarditis experienced symptoms within 3 days of vaccination. Around half required admission to hospital for treatment in hospital and of those most were discharged within 4 days.

Our analysis of the likely myocarditis cases suggests they are reported more frequently in teenage boys, particularly after the second dose (5.2 cases per 100,000 doses) compared to the general population after a first or second dose (0.8 per 100,000 doses). This has been observed in other countries including in the US where a large number of doses have been given, including in children. The estimated reporting rates in Australia appear similar to overseas rates.

We continue to monitor and review Australian data on myocarditis and will provide regular updates in this report as more information becomes available. We are also working closely with international medicines regulators to share emerging safety information.

For more information, see guidance on myocarditis and pericarditis developed by ATAGI and the Cardiac Society of Australia and New Zealand (CSANZ).

Comirnaty (Pfizer) vaccine

To 17 October 2021, approximately 19.6 million doses of Comirnaty (Pfizer) have been administered in Australia. The reports of suspected side effects we receive for this vaccine are consistent with what has been observed in the clinical trials and by other medicine regulators overseas. Most side effects resolve within a few days.

The TGA is actively monitoring myocarditis and pericarditis and continues to work with international regulators on this safety signal (see above).

Up-to-date information about Comirnaty (Pfizer) can be found in the Consumer Medicine Information (for consumers) and Product Information (for health professionals).

Spikevax (Moderna) vaccine

The Spikevax (Moderna) vaccine is now being rolled out in Australia. From approximately 397,000 doses given to 17 October 2021, we have received 498 reports of suspected adverse events associated with the vaccine. In general, these were expected reactions consistent with what has been reported in the trials and included injection-site reactions, headache, chest pain, dizziness and nausea. We are actively investigating reports of myocarditis and pericarditis with this vaccine (see above).

Up-to-date information about the expected side effects of Spikevax (Moderna) can be found in the Consumer Medicine Information (for consumers) and Product Information (for health professionals).

Vaxzevria (AstraZeneca) vaccine

To 17 October 2021, approximately 12.6 million doses of Vaxzevria (AstraZeneca) have been administered in Australia. The reports of suspected side effects we receive for this vaccine are consistent with what has been observed in the clinical trials and by other medicine regulators overseas. Most side effects resolve within a few days.

We are closely monitoring rare reports of blood clots with low blood platelets (also called thrombosis with thrombocytopenia syndrome or TTS) linked to Vaxzevria (AstraZeneca).

Thrombosis with thrombocytopenia syndrome (TTS)

Early detection of TTS may help to prevent more serious complications developing. Guidance for health professionals is now available which outlines when to suspect TTS, initial tests that can be performed in primary care and when to refer people for emergency care. Patients presenting with low platelets and a headache should be thoroughly investigated for blood clots in the brain, including careful review of imaging results to identify early, small clots. The Royal Australian and New Zealand College of Radiologists have published imaging recommendations for patients with suspected TTS.

People should seek immediate medical attention if they develop any of the following symptoms after vaccination:

severe or persistent headache, blurred vision, confusion or seizures
shortness of breath, chest pain, leg swelling or persistent abdominal pain
unusual skin bruising and/or pinpoint round spots beyond the site of vaccination.

The most common time period for onset of TTS symptoms is 4–30 days after vaccination.

To date, there have been 156 cases of TTS assessed as related to Vaxzevria (AstraZeneca) from approximately 12.6 million vaccine doses. These cases most often occurred about 2-3 weeks after vaccination. The risk of TTS after a second dose appears to be much lower than after the first dose. Women in younger age groups seem to be slightly more likely to develop clots in unusual locations, such as the brain or abdomen, which have more serious outcomes. Eight people have died as a result of TTS – 6 of these were women. In Australia, the risk of dying from TTS after vaccination is approximately 1 in a million (people receiving a first dose), and somewhat less than this when both doses are taken into consideration.

While TTS is very rare, some people may have concerns that they can discuss with their doctor. 'Weighing up the potential benefits against risk of harm from COVID-19 Vaccine AstraZeneca' includes information to help people make informed decisions about vaccination.

Details of TTS cases to date

Since last week, 4 additional reports of blood clots and low blood platelets have been assessed as probable TTS likely to be linked to the first dose of Vaxzevria (AstraZeneca). One of the new cases of TTS reported this week was in an individual aged under 60 years (Table 2). We are closely monitoring rates in younger age groups. To date, the reporting rate of TTS remains higher in people aged under 60 years (2.5 per 100,000 doses) compared to those aged 60 and over (1.8 per 100,000 doses), which has also been observed in the UK. However, we have not seen a rise in the incidence in younger people.

Table 2: Newly confirmed and probable TTS cases for the week of 15-21 October 2021‡
New confirmed TTS	New probable TTS
No new cases	Four new cases: 45-year-old man from Victoria 67-year-old man from Queensland 67-year old man and 95-year old woman from NSW

‡As previously reported, the TGA determines whether a report is likely to represent TTS by assessing cases against accepted criteria established by the UK’s Medicines and Healthcare products Regulatory Agency.

Following review of further information, one previously reported case was reclassified from probable to confirmed TTS. This takes the total Australian reports assessed as TTS following Vaxzevria (AstraZeneca) to 156 cases (86 confirmed, 70 probable) from approximately 12.6 million vaccine doses. Sadly, an individual with probable TTS died while in hospital. Information from the coroner indicates that their death was caused by other health conditions and was not related to TTS. Therefore, this case is not being included in the total number of TTS-related deaths.

To date, 19 cases of TTS have occurred after the second dose. Thirteen cases have been assessed as probable TTS, with 6 cases assessed as confirmed TTS. All cases have occurred in individuals older than 50 years, with 16 of the cases in people over 60 years of age. The vast majority of the patients had clots in common locations, such as the lungs or legs, with only 3 cases classified as Tier 1 (see below). The information available to us indicates that only one of these patients required treatment in the intensive care unit, and 18 individuals have been discharged from hospital. Our preliminary analysis is consistent with overseas investigations which have shown that the risk of TTS after the second dose is extremely low.

When assessed against the criteria used by the US Centers for Disease Control and Prevention (CDC), approximately one third of the cases reported to the TGA are classified as Tier 1 cases which tend to have more serious outcomes. Tier 1 cases involve clots in an unusual location, such as the brain or abdomen (Table 3). Australian data indicates that patients aged under 50 years of age are more likely to be classified as Tier 1 and/or require treatment in intensive care. However, more than one third of these younger patients have not required treatment in intensive care.

Table 3: Total confirmed and probable TTS cases to date by age and CDC classification
Age	Total cases	Reports per 100,000 doses‡	CDC classification†
Age	Total cases	Reports per 100,000 doses‡				Tier 1	Tier 2	Not classified
<30 years	8	2.0 (<50 years)	2	4	2
30-39	5		4	1	-
40-49	10		6	1	3
50-59	36	3.0	19	11	6
60-69	37	1.6	11	9	17
70-79	41	2.1	10	12	19
80+	19	1.8	4	9	6
All ages	156 (79 men, 77 women)	2.0	56 (20 men, 36 women)	47 (28 men, 19 women)	53 (31 men, 22 women)

‡ Rates of TTS are calculated based on first doses of the Vaxzevria (AstraZeneca) vaccine as of 7 October 2021 to account for the time to onset of TTS. These rates are estimates of risk based on small numbers of cases so far. An aggregated rate is given for people aged 18–49 years as the number of cases for each 10-year age bracket is too low to calculate reliable estimates.

† The US CDC classification is defined as:

Tier 1 = clots in an unusual location (such as the brain or abdomen) and a low platelet count with or without antibodies that activate platelets (anti-PF4 antibodies)
Tier 2 = clots found in common locations (such as the leg or lungs) and a low platelet count and anti-PF4 antibodies
Not classified = case does not meet the criteria for Tier 1 or Tier 2 (for example clots in common locations with low platelet count but no evidence of anti-PF4 antibodies).

Cases have most often occurred about 2 weeks after vaccination, although the time to onset (or diagnosis) has ranged from 1-100 days (Table 4).

Table 4: Time to onset, treatment and outcomes for TTS cases*
Time to onset/ diagnosis (days)	Median (range)	13 (1-83)
Treated in ICU	At any point	47
	Currently	0
Outcome†	Discharged	139
	In hospital	8
	Fatal	8

*Data is based on the most recent medical information available to the TGA

†As reported in the text above, one patient died from unrelated medical conditions while being treated for TTS. The outcome for this patient is not included in this table.

Other safety signals with Vaxzevria (AstraZeneca)

Guillain-Barre Syndrome (GBS)

GBS is a rare immune disorder affecting the nerves and can result in pain, numbness, muscle weakness and difficulty walking. It has been associated with COVID-19 infection as well as other infectious diseases. Following rigorous investigations by the TGA and other international drug regulators, a clear link between GBS and Vaxzevria (AstraZeneca) has not been established. However as a precautionary measure, a warning statement about GBS has been added to the Product Information in response to rare cases following vaccination.

To 17 October 2021, the TGA has received 131 reports of suspected GBS occurring after vaccination with Vaxzevria (AstraZeneca) giving a reporting rate of approximately one cases for every 100,000 people vaccinated. It is expected that some suspected cases may not be related to vaccination, as GBS can occur after common viral infections and some types of gastroenteritis.

We encourage people to seek medical attention if they experience symptoms that could suggest GBS as early medical care can reduce severity and improve outcomes. Symptoms to look out for include weakness and paralysis in the hands or feet that can progress to the chest and face over a few days or weeks. These tend to affect both sides of the body.

Immune thrombocytopenia (ITP)

The TGA continues to monitor reports of suspected ITP, a type of thrombocytopenia or low platelet count. Following an investigation by the TGA, the Product Information will be updated to include a new warning about ITP.

To 17 October 2021, the TGA has received 85 reports of suspected ITP following vaccination with Vaxzevria (AstraZeneca) giving a reporting rate of less than one case for every 100,000 people vaccinated. These patients had an extremely low platelet count, and signs of thrombocytopenia which may include unusual bruising, a nosebleed and/or blood blisters in the mouth. Their symptoms occurred in a timeframe that suggested they could be linked to vaccination and no other obvious cause was identified based on the information provided to TGA. Apart from one fatal case that was assessed by an expert Vaccine Safety Investigation Group as being likely to be vaccine related, suspected cases of ITP have not been definitively linked to vaccination.

ITP can occur when the immune system is activated and mistakenly destroys platelets which help blood to clot. This can happen sometimes after a viral infection or vaccination. In many cases it is mild with up to a third of people having no symptoms at all, or only minor bruising. However, about 5% develop severe bleeding.

We encourage people to seek medical attention if they experience signs and symptoms that could suggest ITP, such as unusual skin bruising or clusters of small red or purple spots that do not lose their colour when pressed. Unusual bleeding is another sign, for example bleeding from the nose or mouth that is hard to stop, or blood in the urine or stools.

Up-to-date information about the expected side effects of Vaxzevria (AstraZeneca) can be found in the Consumer Medicine Information (for consumers) and Product Information (for health professionals).