Misplaced Pages

Revision as of 18:33, 13 April 2021

It has been suggested that this article be merged into Oxford–AstraZeneca COVID-19 vaccine. (Discuss) Proposed since April 2021.

This article or section is in a state of significant expansion or restructuring. You are welcome to assist in its construction by editing it as well. This template was placed by Djm-leighpark (talk · contribs). If this article or section has not been edited in several days, please remove this template. If you are the editor who added this template and you are actively editing, please be sure to replace this template with {{in use}} during the active editing session. Click on the link for template parameters to use. This article was last edited by Huasteca (talk | contribs) 3 years ago. (Update timer)

This article needs to be updated. The reason given is: Briefings from MHRA and EMA on 7 April 2021 have provided additional information with some useful details not brought to the article, e.g. distribution of age and gender.. Please help update this article to reflect recent events or newly available information. (April 2021)

Part of a series on the
COVID-19 pandemic
COVID-19 (disease) SARS-CoV-2 (virus) Cases Deaths
Timeline 2019 2020 January responses February responses March responses April responses May responses June responses July responses August responses September responses October responses November responses December responses 2021 January responses February responses March responses April responses May responses June responses July responses August responses September responses October responses November responses December responses 2022 January responses February responses March responses April responses May responses June responses July responses August responses September responses October responses November December 2023
Locations By country and territory Africa Antarctica Asia Europe North America Oceania South America By conveyance Cruise ships Naval ships
International response Endemic phase Evacuations Face masks International aid Origin Lockdowns by country Misinformation by governments Fake treatments Social distancing Software Travel United Nations World Health Organization WTO IP waiver Undercounting of deaths COVID-19 apps Zero-COVID National responses Africa China European Union Germany Ghana India Ireland Netherlands New Zealand Nigeria Philippines Russia Sweden UK government US federal government Vietnam
Medical response Disease testing Breathalyzer Development Drug development Drug repurposing Public health mitigation Vaccines History Research VITT Deployment Authorizations Operation Warp Speed Misinformation and hesitancy US Vaccine card Vaccine passports Current vaccines CoronaVac Covaxin Convidecia Janssen Medigen Moderna Novavax Oxford–AstraZeneca Pfizer–BioNTech Sinopharm BIBP Sputnik V
Variants Variants of concern Alpha Beta Gamma Delta Omicron Other variants Epsilon Zeta Eta Theta Iota Kappa Lambda Mu Cluster 5 Lineage B.1.617
Economic impact and recession Arts and culture Aviation Cannabis Cinema films Disney Fashion Financial markets Food industry Food security Journalism Music Performing arts Retail Shipping Television US sportscasting programs Tourism Video games By country Canada India Ireland Malaysia New Zealand Russia UK US By sport Association football Baseball Basketball Combat sports Cricket Disc golf Gaelic games Gridiron football Ice hockey Motorsport Rugby league
Impacts Long COVID Neurological and psychological symptoms Post-exertional malaise Society Animals Alzheimer's disease patients Black people Crime Death rates by country Disability Domestic violence Emergency evacuations Education Female Environment Hospitals Language LGBT community Long-term care Media coverage Mental health Migration Military Notable deaths Other health issues Popular culture Protests Pregnancy Prisons Religion Catholic Church Hajj Science and technology Social media Strikes Suicides Telehealth Xenophobia and racism Politics Diplomacy Ireland Malaysia New Zealand Russia UK US
COVID-19 portal
v t e

Post-vaccination embolic and thrombotic events (also termed vaccine-induced prothrombotic immune thrombocytopenia (VIPIT) or vaccine-induced thrombocytopenia and thrombosis (VITT)) are rare types of blood clotting events that have been observed in a very small number of people who had previously received the Oxford–AstraZeneca COVID-19 vaccine (AZD1222) (later renamed to Vaxzevria) during the COVID-19 pandemic. On 13 April 2021, AstraZeneca and the EMA updated their information for healthcare professionals about the vaccine, saying it is "considered plausible" that there was a causal relationship between between vaccination and the occurrence of thrombosis and thrombocytopenia and that, "although such adverse reactions are very rare they exceeded what would be expected in the general population".

Signs and symptoms

This section is in a state of significant expansion or restructuring, and is not yet ready for use. You are welcome to assist in its construction by editing it as well. This template was placed by Djm-leighpark (talk) 08:15, 11 April 2021 (UTC). If this section has not been edited in several days, please remove this template. If you are the editor who added this template and you are actively editing, please be sure to replace this template with {{in use}} during the active editing session. Click on the link for template parameters to use. This article was last edited by Huasteca (talk | contribs) 3 years ago. (Update timer)

The symptoms listed as the side effects of low levels of blood platelets are indicated as presenting in the period between about day four and week four after vaccination. Symptoms include shortness of breath, chest pain, leg swelling, persistent abdominal pain, neurological symptoms (particularly severe and persistent headaches or blurred vision), and tiny blood spots under the skin beyond the site of the injection.

It should be noted COVID-19 vaccines have some adverse effects that are listed as common in the two or three days following vaccination which are usually mild and temporary.

Causes

This section is in a state of significant expansion or restructuring, and is not yet ready for use. You are welcome to assist in its construction by editing it as well. This template was placed by Djm-leighpark (talk) 08:15, 11 April 2021 (UTC). If this section has not been edited in several days, please remove this template. If you are the editor who added this template and you are actively editing, please be sure to replace this template with {{in use}} during the active editing session. Click on the link for template parameters to use. This article was last edited by Huasteca (talk | contribs) 3 years ago. (Update timer)

Blood clots occur at a background rate in the general population though the combination of low levels of blood platelets with blood clots is seen more rarely. Regulatory authorities have detected a very small number of such events after COVID-19 vaccinations, at what may be higher rates than expected, sometimes accompanied by bleeding. These events have let to:

• Cerebral venous sinus thrombosis (CVST), blood clots appearing in the brain.
• Splanchnic vein thrombosis, bloods clots in the abdomen.
• Blood clots in arteries.
• Disseminated intravascular coagulation (DIC), abnormal blood blotting throughout the blood vessels of the body.

Epidemiology

This section needs to be updated. The reason given is: Needs to ensure latest data is reflected. Marked as inacc as the information presented presented was not originally presented as forming the basis of an "Epidemiology" section, but discussion of age and possibly gender on the topic are relevant as vaccinations by countries may not have been spread evenly throughout ages genders.. Please help update this article to reflect recent events or newly available information. (April 2021)

The Paul Ehrlich Institute has recorded 31 cerebral venous sinus thromboses (CVST) and nine deaths out of 2.7 million vaccinated in Germany with the AZD1222. On 2 April 2021 the UK's Medicines and Healthcare Products Regulatory Agency reported 22 cases of CVST and a further eight cases of clotting problems both associated with a low level of blood platelets following a "rigorous review" of its Yellow Card reporting. The institute also reported finding no events of this type which occurred after vaccination with the Pfizer–BioNTech COVID-19 vaccine. The EMA had earlier said that a link between certain very rare blood clots and the AstraZeneca vaccine is "not proven, but is possible".

Observations in Germany of these rare events seemed to relate mostly women aged under 55. However, because Germany had previously restricted AZD1222 to under 65s, the population vaccinated there with AZD1222 was comparatively younger, and consequently contained a higher proportion of women taking the contraceptive pill. As CVSTs are more likely in women using hormonal contraceptives, this inherent risk factor may be an influence on the reported preponderance of women experiencing these events following vaccination. The UK, in contrast, has applied its Pfizer and AZD1222 vaccines generally to older groups first, then by decreasing age.

Regulatory status

According to the European Medicines Agency (EMA), as of 28 March 2021, the reported rate of such events was lower than in the general population overall, but higher than in the population prior to the pandemic. The EMA also said that there is no proof that these events are caused by the vaccines, but that the possibility could not yet be ruled out completely. Accordingly, the EMA advised that people who received the vaccine and experienced symptoms suggestive of thrombosis, including shortness of breath, blurred vision and severe or persistent headache, should seek medical attention.

In a press briefing in the Afternoon of 7 April 2021 by Emer Cooke executive director of the EMA began by stating "Our safety committee, the Pharmacovigilance and Risk Assessment Committee (PRAC) of the European Medicines Agency, has confirmed that the benefits of the AstraZeneca vaccine in preventing COVID-19 overall outweigh the risks of side effects. COVID-19 is a very serious disease with high hospitalization and death rates and every day COVID is still causing thousands of deaths across the EU. This vaccine has proven to be highly effective, it prevents severe disease and hospitalization, and it is saving lives. Vaccination is extremely important in helping us in the fight against COVID-19 and we need to use the vaccines we have to protect us from the devastating effects". She went on to say "The PRAC after a very in-depth analysis has concluded that the reported cases of unusual blood clotting following vaccination with the astrazeneca vaccine should be listed as possible side effects of the vaccine". At the same briefing Dr. Samina Strauss of PRAC confirmed "our conclusion is that these clotting disorders are very rare side effects of the vaccine".

The UK MHRA also held a news conference on 7 April 2021 and while there was no proof the AZD1222 vaccination caused the rare blood clots but indicated the possibility of a link was getting stronger. The UK was to offer under 30s alternative vaccines. The reasoning was because in the 20-29 age range the benefits to individual of vaccination were less as their likelihood of harm from COVID-19 was less and closer to the potential risk of harm from the vaccine (at a medium exposure risk with COVID-19 infection cases running at a rate of 60 per 100,000). For higher age groups the benefit to risk ratio increased.

Also on 7 April 2021 an interim statement from the WHO said its advisory body, GACVS, found any "causal relationship" between the rare blood clot cases and AZD1222 to be "plausible but is not confirmed".

Outcomes

Early reports indicate the outcome is fatal in a proportion of cases, for example the UK MHRA reporting regards ADZ1222 to 31 March 2021 recording 19 deaths out of 79 cases in the context of 20.2 million doses administered.

History

Organisations

Global vaccine safety comes under the remit of the World Health Organization (WHO), and in particular its Global Advisory Committee on Vaccine Safety (GAVCS). Other drug regulatory agencies significantly involved include:

• European Medicines Agency (EMA), the regional regulatory authority for the EU.
• Medicines and Healthcare products Regulatory Agency (MHRA), the medical authority for the United Kingdom.
• Paul Ehrlich Institute (PEI), a German federal agency supervised by the Federal Ministry of Health with expertise in vaccines and biomedicines. It is a WHO collaborating centre.

Syndrome identification

A number of COVID‑19 vaccines began to become approved and available at scale in late 2020 with vaccinations beginning to ramp up at scale from the beginning of 2021, among them the Oxford–AstraZeneca COVID-19 vaccine, based on an adenovirus vector and internally termed AZD1222.

On 11 March 2021 the EMA issued a statement noting Denmark had suspended AZD1222 vaccinations due to a vaccinated patient dying with blood clots. While noting there had been reports of other vaccinated people having blood clots and that its safety committee was already reviewing such cases, the number of thromboembolic events in vaccinated people was no higher than in the general population.

The World Health Organization (WHO) Global Advisory Committee on Vaccine Safety thought necessary on 19 March 2021 to issue a statement relating to safety signals related to AZD1222 relating to thromboembolic events and thrombocytopenia following review of available data and conclusions included that AZD1222 "a positive benefit-risk profile, with tremendous potential to prevent infections and reduce deaths across the world".

In its safety update of 29 March 2021 the EMA indicated it had initiated investigations into the very rare cases of specific embolic and thrombotic events in combination with thrombocytopenia (low levels of blood platelets) and related bleeding including disseminated intravascular coagulation and cerebral venous sinus thrombosis (CVST), noting any link with AZD1222 was not proven but could not be excluded. The EMA also initiated an assessment for all COVID-19 vaccines used in the EU for immune thrombocytopenia (ITP), described as low blood platelet levels that could lead to bruising and bleeding, as a possible side effect, whilst also stating that up to this point no link with any COVID-19 had been established.

On 7 April 2021 the EMA determined that that unusual blood clots with low blood platelets should be listed as very rare side effects of AZD1222, with WHO and UK EHRA issuing generally similar statements on the same day. None of the agencies found a confirmed causal link between the vaccine and these incidents at the time, but were listing them out of an abundance of caution.

A highlight of minutes of the EMA's Pharmacovigilance Risk Assessment Committee (PRAC) concluding 9 April 2021 indicating they also were investigating four cases of unusual blood clots with low blood platelets, including 1 death, from the Johnson & Johnson COVID-19 vaccine (J&J). The J&J vaccine was approved but not yet deployed in the EU, though vaccinations are in progress in the USA. PRAC has determined that it is currently not clear if there is a causal association. Should regulatory action prove necessary, PRAC have indicated the likely outcome would be an update to product information characteristics.

Vaccination campaign responses

Early reports of the events of concern seemed to indicate the presentation rate for the specific blood clots of concern might be higher for women of younger ages, UK MHRA found examples across all genders and ages, their data skewing towards these specific blood clots being more prevalent in AZD1222 vaccinated persons of younger ages.

The WHO has continued to stress the administration of vaccines is based on risk versus benefit analysis. Some variables that may be factored into such analysis include risk of an individual from catching COVID-19, which relate to the infection rate in that area, and the benefits to that individual if vaccinated and exposed to COVID-19 which varies with age, versus whatever the risks of vaccination are to that individual.

Regional and national responses

This section needs expansion. You can help by adding to it. (April 2021)

The advisory panel for the government of Ontario, Canada has recommended against the use of heparin for management of thrombosis after vaccination until more is known.

In response to the concerns over the adverse effects relating to rare blood clotting types Germany has suspended use of the AZD1222 in those under 60 years of age; in contrast to a period previously having suspended use of AZD1222 to over–65s due to limited data of the efficacy of the vaccine to this age group at that time.

Following a few days of suspended use of AZD1222, the Ministry of Health, Welfare and Sport of the Netherlands decided to continue administering the vaccine only to persons above the age of 60.

On 8 April 2021, the Australian Technical Advisory Group on Immunisation (ATAGI) advised the Australian Government that the Pfizer COVID-19 vaccine is recommended over AZD1222 for adults aged under 50 years. The advice is "based on the increasing risk of severe outcomes from COVID-19 in older adults (and hence a higher benefit from vaccination) and a potentially increased risk of thrombosis with thrombocytopenia following AstraZeneca vaccination in those under 50 years." ADZ1222 is still recommended by ATAGI for people over 50, and those under 50 who have already had their first dose with no ill effects. In the state of Victoria, there were reports of some, aged under 50, being turned away from vaccination centres, despite having confirmed appointments. It is understood a special consent process will be developed by the Australian Government for people under 50 who choose to receive the AZD1222 vaccine.

References

Footnotes

1. ^ Public Health Agency of Canada, (29 March 2021). "Use of AstraZeneca COVID-19 vaccine in younger adults" (Utilisation du vaccin AstraZeneca contre la COVID-19 chez les jeunes adultes). Government of Canada. Retrieved 2 April 2021.
2. ^ "COVID-19 vaccine safety update: VAXZEVRIA" (PDF). European Medicines Agency. 28 March 2021. Retrieved 31 March 2021.{{cite web}}: CS1 maint: url-status (link)
3. "Direct healthcare professional communication (DHPC): Vaxzevria (previously COVID-19 Vaccine AstraZeneca): link between the vaccine and the occurrence of thrombosis in combination with thrombocytopenia" (PDF). European Medicines Agency. 13 April 2021. Retrieved 13 April 2021.{{cite web}}: CS1 maint: url-status (link)
4. MHRA (1 April 2021). "Research and analysis — Coronavirus vaccine - weekly summary of Yellow Card reporting". gov.UK. Retrieved 3 April 2020.
5. EMA (2021).
6. ^ EMA (7 April 2021). "AstraZeneca's COVID-19 vaccine: EMA finds possible link to very rare cases of unusual blood clots with low blood platelets". EMA. Retrieved 9 April 2021.
7. ^ Gallagher J (2 April 2021). "AstraZeneca: Is there a blood clot risk?". BBC. Retrieved 3 April 2021.
8. ^ Gallagher J (3 April 2021). "Covid-19: Seven UK blood clot deaths after AstraZeneca vaccine". BBC. Retrieved 3 April 2021.
9. ^ Greinacher, Andreas; Thiele, Thomas; Warkentin, Theodore E.; Weisser, Karin; Kyrle, Paul A.; Eichinger, Sabine (9 April 2021). "Thrombotic Thrombocytopenia after ChAdOx1 nCov-19 Vaccination". New England Journal of Medicine: NEJMoa2104840. doi:10.1056/NEJMoa2104840. Retrieved 11 April 2021.
10. EMA (2021), 8m.
11. EMA (2021), 9m.
12. EMA (2021), 14m.
13. ^ Triggle, Nick (7 April 2021). "Covid: Under-30s offered alternative to Oxford-AstraZeneca jab". BBC News. Retrieved 8 April 2021.
14. ^ Winton Centre for Risk and Evidence Communication, University of Cambridge (7 April 2021). "Communicating the potential benefits and harms of the Astra-Zeneca COVID-19 vaccine" (Presentation PDF). wintoncentre.maths.cam.ac.uk. Retrieved 9 April 2021. {{cite news}}: External link in |format= (help)
15. ^ GACVS (7 April 2021). Interim statement of the COVID-19 subcommittee of the WHO Global Advisory Committee on Vaccine Safety on AstraZeneca COVID-19 vaccine (Report). World Health Organization. Retrieved 9 April 2021.
16. ^ Medicines and Healthcare Products Regulatory Agency (7 April 2021). "MHRA issues new advice, concluding a possible link between COVID-19 Vaccine AstraZeneca and extremely rare, unlikely to occur blood clots" (Press release). GOV.UK. Retrieved 12 April 2021. Up to and including 31 March 2021, the MHRA had received 79 UK reports of blood clotting cases alongside low levels of platelets following the use of the COVID-19 Vaccine AstraZeneca:" "in 51 women and 28 men, aged from 18 to 79 years.
17. World Health Organization. "Collaborating centres: Blood products and related biologicals". www.who.int. Retrieved 10 April 2021.
18. "COVID-19 Vaccine AstraZeneca: PRAC investigating cases of thromboembolic events - vaccine's benefits currently still outweigh risks - Update". European Medicines Agency. 11 March 2021. Retrieved 9 April 2021.{{cite web}}: CS1 maint: url-status (link)
19. GACVS (19 March 2021). "Statement of the WHO Global Advisory Committee on Vaccine Safety (GACVS) COVID-19 subcommittee on safety signals related to the AstraZeneca COVID-19 vaccine". World Health Organization. Retrieved 6 April 2021.
20. PRAC (9 April 2021). "Meeting highlights from the Pharmacovigilance Risk Assessment Committee (PRAC)". EMA. Retrieved 9 April 2021.
21. "Vaccine-Induced Prothrombotic Immune Thrombocytopenia (VIPIT) Following AstraZeneca COVID-19 Vaccination". Ontario COVID-19 Science Advisory Table. Retrieved 3 April 2021.
22. "Covid: How does the Oxford-AstraZeneca vaccine work?". BBC. 6 April 2021. Retrieved 6 April 2021.
23. Ministerie van Volksgezondheid, Welzijn en Sport (8 April 2021). "Prikken met AstraZeneca voor mensen van 60 jaar en ouder gaat door - Nieuwsbericht - Rijksoverheid.nl". www.rijksoverheid.nl (in Dutch). Retrieved 8 April 2021.
24. ^ Australian Government, Department of Health (8 April 2021). "ATAGI statement on AstraZeneca vaccine in response to new vaccine safety concerns". Australian Technical Advisory Group on Immunisation. Retrieved 9 April 2021.
25. ABC News (9 April 2021). "People under 50 turned away from Melbourne vaccination centre after new AstraZeneca advice". www.abc.net.au. Retrieved 9 April 2021.

Sources

• EMA (7 April 2021). EMA press conference 7th April — Conclusion of the assessment of the Pharmacovigilance Risk Assessment Committee (PRAC) of COVID-19 Vaccine AstraZeneca and thromboembolic events. European Medicines Agency (EMA). Retrieved 7 April 2021 – via Youtube.

• Medicine
• Viruses
• COVID-19

• Articles to be merged from April 2021
• COVID-19 pandemic
• COVID-19 vaccines
• AstraZeneca brands