The different types of vaccines
- There are three main approaches to designing a vaccine.
- Their differences lie in whether they use a whole virus or bacterium; just the parts of the germ that triggers the immune system; or just the genetic material that provides the instructions for making specific proteins and not the whole virus.
Types of CoVID-19 Vaccines:
- There are four main types of CoVID 19 vaccinations-
Whole virus vaccine:
- These have the live attenuated and inactivated vaccines types.
- These require only conventional storage conditions.
- India’s COVAXIN is an inactivated type.
Protein sub-unit vaccine:
- The viral subunit is mixed with adjuvants to help stimulate an immune response.
- They are expensive to produce and may require booster doses.
- NOVAVAX is of such category.
mRNA (nucleic acid) vaccine:
- The RNA code of the SARS CoV-2 virus is inserted into the host cell whose protein machinery interprets it to produce viral antigens.
- The host body then produces antibodies in response and develops immunity against the SARS CoV-2.
- These are easy to make and cheaper to produce, but this has never been used by humans before.
- They require extreme cold storage of -70 degrees Celsius.
- Pfizer and Moderna vaccines are such types.
Viral vector vaccine:
- They also work by giving cells genetic instructions to produce antigens.
- But they differ from nucleic acid vaccines because they use harmless viral vectors like adenovirus to deliver these instructions.
- Our cellular machinery is hijacked by them to produce antigens which then trigger the immune response.
- They require only conventional cold storage.
- COVISHIELD and Russia’s Sputnik belong to this category.