UPSC Prelims 2022 Q39: COVID-19 Vaccine Platforms — Explained
In the context of vaccines manufactured to prevent COVID-19 pandemic, consider the following statements:
1. The Serum Institute of India produced COVID-19 vaccine named Covishield using mRNA platform.
2. Sputnik V vaccine is manufactured using vector based platform.
3. COVAXIN is an inactivated pathogen based vaccine.
Which of the statements given above are correct?
- 1 and 2 only
- 2 and 3 only
- 1 and 3 only
- 1, 2 and 3
Answer: (b) 2 and 3 only
Statement-wise explanation
- 1: incorrect — The Serum Institute of India makes Covishield, but Covishield is a viral vector vaccine, not an mRNA vaccine. It is the Oxford-AstraZeneca ChAdOx1 vaccine. PIB's January 2022 backgrounder says it 'contains a weakened strain of a common cold virus (adenovirus) from chimpanzees'. The same backgrounder says India had no mRNA vaccine yet; Gennova was only 'in the running for being India's first mRNA vaccine'.
- 2: correct — Sputnik V, officially Gam-COVID-Vac, was developed by Russia's Gamaleya National Research Center. The Health Ministry called it a 'combined vector vaccine' with two components. Each dose uses a different harmless human adenovirus (Ad26, then Ad5) to carry the spike-protein gene. India's drug regulator approved it for restricted emergency use on 13 April 2021, on an application from Dr. Reddy's Laboratories.
- 3: correct — Bharat Biotech developed COVAXIN with ICMR's National Institute of Virology (NIV), Pune. PIB says it uses 'Whole-Virion Inactivated Vero Cell derived platform technology'. The vaccine contains killed virus that cannot infect but still trains the immune system. WHO gave it Emergency Use Listing on 3 November 2021 as a whole-virion inactivated SARS-CoV-2 vaccine.
How to eliminate
The options are built so that Statement 1 alone settles the question. Three of the four options include Statement 1, and only one leaves it out. So if you know that Covishield is the Oxford-AstraZeneca adenovirus vaccine and not mRNA, you can reach the answer without judging Statements 2 and 3. Basic knowledge from 2021 also helps. India's well-known mRNA vaccines were foreign (Pfizer-BioNTech and Moderna), and none was in India's programme before the 2022 exam. Covaxin was widely reported as the 'killed virus' vaccine, which confirms Statement 3. No absolute words help here. The fact to remember is the platform pairing: Covishield and Sputnik V are adenovirus vector vaccines, and Covaxin is an inactivated vaccine.
Know more
How COVID-19 vaccines teach the immune system
Every COVID-19 vaccine shows the body the virus's spike protein, or the whole virus, so the body learns to recognise it. The platform is the way that antigen is delivered.
| Platform | How it works | Examples |
|---|---|---|
| Inactivated (whole virion) | Virus grown in cells (e.g., Vero cells), then killed chemically | COVAXIN (Bharat Biotech–ICMR) |
| Viral vector (non-replicating) | A harmless adenovirus carries the spike gene into cells | Covishield (chimpanzee adenovirus), Sputnik V (human Ad26 + Ad5) |
| mRNA | Lipid-coated mRNA tells cells to make the spike protein | Pfizer-BioNTech, Moderna; Gennova (India) |
| DNA (plasmid) | Circular DNA carries the spike gene; given needle-free | ZyCoV-D (Zydus Cadila), the world's first DNA COVID-19 vaccine |
| Protein subunit | Purified spike protein (or part of it) plus an adjuvant | Corbevax (Biological E), Covovax (Serum Institute) |
Key points
- A vector vaccine is not a live COVID virus. The adenovirus is changed so it cannot copy itself.
- Sputnik V uses two different vectors for its two doses. This heterologous prime-boost lowers the risk that immunity to the first vector weakens the second dose.
- Inactivated vaccines need high-containment manufacturing because live virus is grown first. COVAXIN is made in a BSL-3 facility.
- mRNA and DNA vaccines carry only genetic instructions, never the virus itself.
- PIB's January 2022 backgrounder noted that India had developed vaccines on several platforms: inactivated (COVAXIN), DNA (ZyCoV-D) and viral vector (Covishield).
Regulatory terms: In India, the CDSCO under the Drugs Controller General of India (DCGI) granted 'restricted use in emergency situation'. Covishield and COVAXIN got this approval in January 2021 and Sputnik V in April 2021. WHO has a separate global approval called Emergency Use Listing (EUL).
In the news
India's COVID-19 vaccination drive marked its first anniversary on 16 January 2022, and India crossed 150 crore doses on 7 January 2022. PIB published a backgrounder that described each vaccine's platform. COVAXIN's WHO Emergency Use Listing in November 2021 also kept vaccine platforms in the news ahead of the June 2022 Prelims.