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Covishield Vaccine and Risks of Hear Attack : A Detailed Breakdown

Covishield is one of the major vaccines used globally against COVID-19. 

What is Covishield?

  • Developed by the Serum Institute of India (SII), Oxford University, and AstraZeneca.

  • Uses a viral vector platform. This means a weakened chimpanzee adenovirus (ChAdOx1) is modified to carry the genetic material for the SARS-CoV-2 virus's spike protein.

  • Once inside human cells, the genetic material instructs cells to produce spike proteins. The immune system then recognizes these proteins as foreign and mounts a defense, preparing the body to fight the actual virus.

How Effective is Covishield?

  • Studies show Covishield to be up to 90% effective in preventing symptomatic COVID-19 illness.

  • Effectiveness may vary depending on factors like age and underlying health conditions.

Dosing Schedule

  • Covishield is administered in two doses, typically 4-12 weeks apart.

Possible Side Effects

  • Covishield, like most vaccines, can cause mild side effects at the injection site, such as pain, redness, or swelling.

  • Other possible side effects include:

  • Fever

  • Headache

  • Fatigue

  • Muscle aches

  • Nausea

  • Serious side effects are rare.

Important Considerations

  • Covishield is not recommended for everyone. People with severe allergies to any of the vaccine components or a history of serious allergic reactions should consult a doctor.

  • Individuals with weakened immune systems or undergoing immunosuppressive therapy may need to discuss vaccination with their doctor.

  • Vaccination is particularly important for those at high risk of complications from COVID-19, such as older adults and people with underlying health conditions.

View on the link between Covishield and heart attacks:

It's a complex issue with ongoing research:

  • Limited evidence: Large studies haven't found a strong connection between Covishield and increased heart attack risk.


  • Potential for rare side effects:  AstraZeneca, the developer behind Covishield, acknowledges a very small possibility of a rare blood clotting condition called Thrombosis with Thrombocytopenia Syndrome (TTS) which can lead to strokes or heart attacks.

  • COVID-19 itself a bigger risk factor:  There's stronger evidence that COVID-19 infection significantly increases the risk of heart problems, including heart attacks. Vaccination offers protection against this risk.

Here's a breakdown of some recent developments:

  • Studies showing no link: A recent observational study in India found no association between Covishield/Covaxin and heart attacks.

  • Concerns and ongoing review:  Some doctors have raised concerns about a possible link,  calling for further investigation.

Reliable sources :

  • Indian Ministry of Health and Family Welfare website

  • World Health Organization (WHO)


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