TBC Explainer: What are Sputnik V, Covaxin and Covisheild made of?
A comprehensive guide to knowing what type of virus does your vaccines contain
As Sputnik V arrives in India, we Indians now have a variety of vaccines available. Though yet, we do not have the choice to choose which vaccine we would like to take, it is important to know what your vaccine is made of. Especially, with the arrival of Sputnik V, it is possible that there will be some improvement in the availability of the vaccine.
However, recently, a lot of questions were also raised on the export of vaccines from India when enough vaccines were not available for the citizens of the country. As per the last released data, India had exported vaccines worth 663.698 million to date. However, not much has been said about the exports after extensive media trials were conducted over the shortage of vaccine.
According to recent data from Bloomberg Vaccine Tracker, after starting the vaccination drive in February 2021, to date, 186 million doses have been administered, which covers 6.8 per cent of the population of the country. According to the same website, India currently has 12.2 per cent of the world's vaccination and 17.7 per cent of the world's population
Even Adar Poonawalla the founder of Serum Institute of India recently confessed in a tweet that his institute was doing its best to ramp up the production of vaccine in India. The tweet read: "Yes@sajjanjindal, we at @SerumInstIndia are doing our best to ramp up production & launch new vaccines on priority for India. We aregrateful for @TheJSWGroup efforts in trying to fulfill India’smedical oxygen needs as we stand together in this fight against this pandemic." (sic)
Apart from Serum, Bharat Biotech the maker of Covaxin is also working towards supplying the country with supplying COVID-19 vaccines in the country. However, India faced a major shortage of vaccine in March and April.
But with the arrival of Sputnik V, there is hope that Indian will now have easy access to the vaccine.
But before you get the vaccine, you must know what Covisheld, Covaxin and Sputnik V are made of. And also compare their efficacy.
One of the most widely available vaccines in India, Covisheild is developed by Oxford-AstraZeneca and is being manufactured by the Serum Institute of India. This vaccine is made from a weakened version of a common cold virus that is found in chimpanzees. However, while making the vaccine, the virus is modified to look more like the coronavirus.
Hence when injected, since the virus looks like coronavirus, the body identifies it as a foreign body and learns to fight with it. Since the virus is in no way related to the actual coronavirus, unless you have contracted Covid-19 you will not test positive for the virus. The virus only looks similar to the virus to prepare the body to fight against the actual virus.
Covisheild is presented in two doses and the same composition is administered in the second dose. A person is considered to be fully vaccinated only after the second dose.
When it comes to vaccine efficacy, International clinical trials of the Oxford-AstraZeneca vaccine show 90 per cent efficacy in people who were given a half dose, and then a full dose. But there isn't enough data to prove that.
However, unpublished data 'suggests that leaving a longer gap between the first and second doses increases the overall effectiveness of the jab - in a sub-group given the vaccine this way it was found to be 70% effective after the first dose.' — BBC news.
Unlike Covisheild, Covaxin is made up of an actual inactivated (killed) coronavirus. This means, the virus is dead and cannot cause any harm to the body. Making it safe for being injected into the body.
When injected into the person, since the composition of the virus is the same, even when dead. The body learns to identify it as a foreign body, prompting the immune system to make antibodies against the virus.
Covaxin is presented in two doses and the same composition is administered in the second dose. A person is considered to be fully vaccinated only after the second dose.
The vaccine has an efficacy rate of 81%, based on preliminary data gathered from its phase 3 trial.
Unlike the other two vaccines, the composition of Sputnik V is a little complex. According to Precession vaccination, '(Sputnik V) It is a vector vaccine based on adenovirus DNA (common cold), in which the SARS-CoV-2 coronavirus gene is integrated. Adenovirus is used as a “container” to deliver the coronavirus gene to cells and start the synthesis of the new coronavirus's envelope proteins, “introducing” the immune system to a potential enemy.'
Simply put, the common cold virus is used to carry a small fragment of the coronavirus gene, which is engineered in such a way that it is harmless in the body. And yet introduces the body to a part of the virus's genetic code. This allows the body to recognise the threat and also develop an immune response to the same.
Unlike the other two vaccines, Sputnik V does not administer the same composition in its second dose. The vaccine uses two different common cold virus varients 26 (hAdv26), type 5 (hAdv5) for the two doses.
The common factor in all the vaccines is that they are made to teach the body to identify a virus like Covid-19 and learn to fight against it. Each vaccine, in its own way, induces an immunogenic response from the body. A vaccine and precautions are the only two ways to defeat the pandemic. And hence it is important that every one takes which ever vaccine is available.