Types of Covid-19 vaccine
One of the unique features of the race to produce a Covid-19 vaccine is the difference between vaccine candidates and vaccine-producing technology.
Accordingly, current Covid-19 vaccines are being produced by three mechanisms:
The vaccine introduces the synthesized RNA molecule into the body's cells. Once inside the cell, the vaccine's synthetic mRNA acts as a native mRNA, initiating the synthesis of a new protein (which is normally synthesized by the virus). This new protein in turn triggers the body's adaptive immune response against the viral protein. Thus, the body receives the vaccine, both creating antigen (virus protein) and creating an immune response against this protein (antibody + cellular response).
This vaccine consists of purified protein fragments of the Sars-Cov-2 virus. After the vaccine is injected into the body, the immune system recognizes that this protein is an "invader" and the immune response produces antibodies. At the same time, vaccines help cells remember to recognize pathogens, proceed to destroy them if attacked in the future.
Vector-based vaccines differ from most conventional vaccines in that they do not actually contain antigens, but use the body's own cells to produce them. Vaccines are manufactured using a modified virus (vector) to deliver the genetic code for the antigen. For the Sars-Cov-2 virus vaccine, the genetic code is spike proteins on the surface of the virus. When the vaccine is injected into the body, it stimulates the body to produce a large amount of antigen. These antigens will trigger an immune response. Vaccines mimic what happens during natural infection with certain pathogens – especially viruses. This has the advantage of triggering a strong cellular immune response by T cells as well as antibody production by B cells.
The Covid-19 pandemic is threatening the health and lives of millions of people worldwide. Scientists are racing against time to have a safe and effective vaccine to prevent the spread of Covid-19.
Up to now, it has been more than 2 years since the Covid-19 pandemic broke out in China, promising Covid-19 vaccines are entering the sprint stages. Accordingly, the brightest Covid-19 vaccine candidates being researched and produced in the world today are:
|1||AstraZeneca||The University of Oxford||Vector vaccine||UK|
|2||Sputnik V||Gamaleya Research Institute||Vector vaccine||Russia|
|3||BNT162b2||Pfizer, BioNTech||mRNA||EU, North America, China|
|5||Ad5-nCoV||CanSino Biologics||Vector vaccine||China|
(spiky protein of SARS-CoV-2 virus)
|10||Covaxin||Bharat Biotech||Inactivated vaccine||India|
|11||Covax-19||Vaxine Pty Ltd||Protein vaccine||Australia|