Today, India has launched the world’s biggest COVID-19 vaccination drive against the deadly coronavirus and with that our government is leaving no stones unturned to educate and inform all of us by creating dialer tones to trust Covid-19 vaccine and stay safe in corona time.
In the first round, 3 crore health and frontline workers will be immunised with one of the two COVID-19 vaccines – Covaxin or Covishield.
Let’s understand how the COVID-19 Vaccines work with the body’s immune system.
This vaccine is developed by Oxford University and AstraZeneca pharma company and manufactured by the Serum Institute of India. Covishield is not formed using a coronavirus strain but using a weakened version of an adenovirus that infects chimpanzees. This adenovirus causes the common cold in chimpanzees but doesn’t cause infection in humans.
Covishield vaccine contains modified adenovirus that allows our cells to make the spike protein like those found on the surface of the coronavirus. When the Covishield vaccine is injected into our body, it prompts our cells to make copies of the coronavirus spike protein. Our immune system then recognizes these spike proteins as foreign. In response, the immune system starts producing antibodies to attack the virus protein. These antibodies will help in fighting the coronavirus if we are infected in the future. Clinical studies showed that the vaccine is safe and 70% effective.
Covishield vaccine is slower because it is a vector vaccine. But the vaccine is cheaper and can be stored at standard refrigerator temperatures for 6 months.
Covaxin is an inactivated vaccine developed by Hyderabad-based biotechnology company Bharat Biotech. Covaxin is produced using one of the oldest methods for vaccination in which the whole virus is used to generate immunity.
To develop the Covaxin, the coronavirus is grown and then killed via heat or some chemicals so that they can’t multiply in the body. But these inactive viruses can still generate an immune response against coronavirus.
Experts are concerned about the effectiveness of the Covaxin because its Phase 3 clinical trial is still underway. However, the phase 1 and 2 clinical trials show that the vaccine is safe. Drug regulators have ordered strict monitoring for Covaxin.
The Indian government has ordered only 55 lakh doses of Covaxin and 11 million doses of Covishield.
Two other Chinese companies- Sinovac and Sinopharm are also using the same whole virus technique to develop coronavirus vaccines.
Pfizer and Moderna vaccines
Pfizer and Moderna vaccines are approved in the US, UK, and other countries. But they are not yet approved for public use in India. The Pfizer and Moderna COVID-19 vaccines are developed using a new technique called mRNA. When the vaccines are injected into the body, the mRNA prompts the cells to make the coronavirus spike protein. Our immune system recognises the spike proteins and produces antibodies to fight against the coronavirus.
These vaccines can be produced quickly because scientists only need the gene of the coronavirus. But these vaccines are fragile and require ultracold temperatures for storage.