In the worldwide battle against the COVID-19 epidemic, vaccinations have shown to be effective weapons. But despite the hope they offer, worries about possible negative effects have emerged. AstraZeneca and the University of Oxford collaborated to produce the Covishield vaccine, which has come under fire recently for claims of serious side effects, including a blood-clotting condition called thrombosis with thrombocytopenia syndrome (TTS).
AstraZeneca, the UK-based pharmaceutical company, has accepted that its COVID-19 vaccine can cause this rare after effect, according to The Telegraph-UK. This development comes after the company was sued over allegations of serious harm and fatalities associated with the vaccine.
This article examines the risks connected to various SARS Covid-19 Vaccines.
Understanding Thrombocytopenia Syndrome (TTS) in Relation to Thrombosis
This syndrome can, in some cases, result from the Covishield vaccine, which was developed by AstraZeneca and Oxford University and is produced by the Serum Institute of India. Throughout India, this vaccine was widely given to people during the Covid-19 pandemic. The other vaccines have been known to have less risk factors.
Low platelet counts and the formation of blood clots in different places of the body are symptoms of TTS, an uncommon but dangerous illness. Blood clotting is a typical reaction to trauma, but aberrant clot production can result in potentially fatal consequences. TTS mainly affects the cerebral venous sinuses, which can result in deep vein thrombosis (DVT) or pulmonary embolism (PE) and even Myocardial infarction(MI). The primary cause of TTS is cerebral venous thrombosis (CVT).
CDC (Centre for Disease control & prevention) has divided TTS into two categories.
Level 1
- Uncommon blood clots, such as those in the stomach or brain, may coexist with more common ones in the lungs or legs.
- Low platelet density—less than 150,000 cells per microliter.
- Although they aren’t usually required, positive anti-PF4 ELISA tests can aid in diagnosis confirmation.
- Tier 1 instances are typically riskier and more severe.
- This is more typical among younger individuals.
Level 2
- Typical blood clots, such as those in the lungs or legs.
- Low platelet density—less than 150,000 cells per microliter.
- To make a diagnosis, an anti-PF4 ELISA test must be positive.
Indications of TTS
Severe headaches, stomachaches, edema in the legs, dyspnea, difficulty breathing, and convulsions are some of the symptoms of TTS. If these symptoms are exhibited, then an immediate doctor’s consultation is mandatory.
The Aftermath Dilemma
What about who received the Johnson & Johnson’s Janssen and Vaxzevria vaccines ?
Covishield has been used extensively in immunization programs all around the world and is based on the adenovirus vector platform. Alarms have been raised, though, by stories that connect Covishield to TTS. Research has indicated that there may be a connection between the vaccine and TTS, especially in younger people who are in their 30’s to 50’s.
It is true that thrombosis with thrombocytopenia syndrome is an uncommon side effect seen in patients who received the Johnson & Johnson/Janssen COVID-19 vaccination in addition to AstraZeneca’s Vaxzevria.
The genetic material for the SARS-CoV-2 spike protein is delivered to the body using adenoviral vectors, which are used by Johnson & Johnson as well as Vaxzevria. It is thought that this technology contributed to the creation of TTS.
Risk Comparison: Studies suggest a slightly higher risk of TTS with Vaxzevria compared to the Johnson & Johnson vaccine. However, the overall incidence remains very low, estimated at a few cases per million doses [Nature Journal, npj Vaccines].
Difficulty in Comparing: Because different nations have varied vaccination programs and surveillance techniques, it is challenging to draw firm conclusions about risk differences.
Current Status: The rare TTS risk has made some regions no longer preferable candidates for adenoviral vector vaccines, such as Vaxzevria, although the Johnson & Johnson vaccine may still be used under certain circumstances [The Melbourne Vaccine Education Centre (MVEC)].
Pfizer-BioNTech, the reasons TTS is unimportant
Pfizer-BioNTech’s uses the mRNA technology. This means it delivers a specific genetic instruction code wrapped in a fatty capsule to the body’s cells. These instructions tell the cells to build temporary copies of the SARS-CoV-2 spike protein, which the immune system recognizes and learns to fight against.
No Viral Components or Vectors: The Pfizer vaccine is devoid of any viral vectors or virus components, in contrast to adenoviral vector vaccines like those produced by AstraZeneca/Covishield, Vaxzevria, and Johnson & Johnson/Janssen. It is thought that this distinction explains why TTS isn’t seen when using mRNA vaccinations.
Pfizer Side Effects: As with any medication, side effects are possible with the Pfizer-BioNTech vaccination. These include injection site pain, lethargy, headaches, muscle aches, chills, and fever; they are often mild and transient.
Is the Risk low for those who took Covovax?
Covovax, also manufactured by the Serum Institute of India, is indeed similar to AstraZeneca’s Vaxzevria (Covishield) in some ways, but with a key difference regarding TTS.
Similarities: Both are recombinant protein vaccines: Covovax and Vaxzevria both use a technology where a harmless version of the SARS-CoV-2 spike protein is produced and introduced into the body. This triggers the immune system to develop defenses against the real virus.
Difference: Delivery Mechanism: This is where things differ. Vaxzevria uses an adenoviral vector to deliver the spike protein information into cells. Covovax, however, doesn’t rely on a vector. Instead, the purified spike protein particles themselves are used in the vaccine formulation.
Lower Risk of TTS with Covovax:
Due to the absence of an adenoviral vector, Covovax is not associated with the rare side effect of TTS (Thrombosis with Thrombocytopenia Syndrome) that has been seen with Vaxzevria.
What about Covaxin ?
Covaxin is a different vaccine altogether compared to Covishield, Vaxzevria, and Johnson & Johnson’s Janssen.
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Vaccine Platform: Covaxin, developed by Bharat Biotech in India, uses an inactivated whole virus platform. This means it contains a weakened or inactivated form of the entire SARS-CoV-2 virus. They contain dead virus, incapable of infecting people but still able to instruct the immune system to mount a defensive reaction against an infection.
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Lower Risk of TTS: Inactivated whole virus vaccines like Covaxin are not linked to TTS (Thrombosis with Thrombocytopenia Syndrome). This side effect is primarily associated with adenoviral vector vaccines like AstraZeneca’s and Johnson & Johnson’s offerings.
Revealing the AstraZeneca Lawsuit
As worries about the safety profile of Covishield grow, AstraZeneca is involved in legal disputes. Lawsuits against the massive pharmaceutical company have been launched, alleging carelessness, failure to provide proper warning about potential hazards, and damages. The plaintiffs contend that AstraZeneca increased the risk of adverse events like TTS by prioritizing speed over safety during the vaccine development process.
The large British pharmaceutical company AstraZeneca has acknowledged that Thrombosis with Thrombocytopenia Syndrome (TTS), an uncommon side effect of the Covid-19 vaccination, can occur. This confession comes after the firm was sued, with claims of serious injury and fatalities related to the vaccine.
COVID-19 Vaccine Side Effects
In 2021, a class-action lawsuit was brought by people who claimed that the AstraZeneca COVID-19 vaccine caused major side effects, such as blood clots. The legal action is still pending. TTS (thrombosis with thrombocytopenia syndrome) is a rare adverse effect that AstraZeneca has acknowledged the vaccination can induce, although it disputes that this is the general cause of all cases [Hindustan Times, US News].
Royalties from the Cancer Drug Zejula
The lawsuit concerns a disagreement with GlaxoSmithKline (GSK) regarding royalties from the medication Zejula. AstraZeneca asserts a higher sales share because of the technology it licensed to produce the medication. The litigation commenced in 2021, and in 2023 GSK prevailed in an appeal before a UK court [Fierce Pharma].
Lawsuits alleging Patent Infringement
AstraZeneca has also brought legal action against generic drug manufacturers, such as Sun Pharma, alleging patent infringement on products like Nexium and Farxiga. Their intellectual property rights are being defended in several different court cases [Business Standard, Life Sciences IP Review].
There have been no reports of large-scale payouts to patients in the COVID-19 vaccine litigation as of today, April 30, 2024. The resolution of these class-action lawsuits may take a while.
MI (Myocardial Infarction) Cases: Insufficient Proof of a Direct Connection
Worries are, there might be a connection between the COVID-19 vaccine and MI (myocardial infarction, or heart attack). There has been a significant rise in cerebral strokes and heart attacks in young patients resulting to deaths in last two years, specially in the Indian subcontinent.
Research has not conclusively shown a cause-and-effect relationship between myocardial infarction and covishield. However, even months after recovery from COVID-19 infection itself is known to raise the chance of Heart Ailments (according to Times, US News).
Pay Attention to Underlying Conditions: Pre-existing risk factors such as smoking, high blood pressure, and cholesterol can contribute to myocardial infarction. It’s possible that in cases reported two years ago, these variables—rather than the vaccine—were more significant.
In rare instances, myocarditis—an inflammation of the heart muscle—may occur as a side effect of COVID-19 vaccinations, including Covishield. Myocarditis is not the same as a heart attack, but problems are not always inevitable.
Advice: See a physician if you have concerns about your heart health following your Covishield treatment. Heart health depends on leading a healthy lifestyle that includes a balanced diet, frequent exercise, and most importantly stress/ anxiety management.
Evidence does not point to a clear causal relationship, even though certain myocardial infarction deaths two years ago may have coincided with Covishield vaccinations. Pre-existing illnesses and the COVID-19 infection itself are more likely to be the cause. For any remaining concerns, seeking individualized guidance from a physician is advised.
The Path Ahead, Building Resilience & Strategies for Safer Vaccination Campaigns
As the worldwide immunization drive advances, striking a balance between the need to stop the spread of SARS Viruses & the like, and vaccine safety will always be crucial. Protecting the public’s health requires strict regulatory control, responsibility in the pharmaceutical sector, and vigilant monitoring of adverse responses. Proactive risk management, evidence-based decision-making, and transparency must direct future efforts to create vaccines.
The discovery that TTS may be a side effect of Covishield highlights the difficulties in developing and implementing vaccines. Although vaccinations are a viable means to escape the pandemic, managing the dangers involved calls for a diversified strategy. The legal issues facing AstraZeneca serve as a reminder of the responsibility pharmaceutical corporations have to ensure the safety of their products.
To overcome these obstacles and rebuild confidence in immunization programs, stakeholders must work together, make educated decisions, and prioritize the interests of public health.
