Types of Covid-19 vaccine

2021-06-06 11:17 PM

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:

mRNA vaccine:

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).

Protein vaccine:

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 vaccine:

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:

# Vaccine name Producer Mechanism


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
4 mRNA-1273 Moderna mRNA USA
5 Ad5-nCoV CanSino Biologics Vector vaccine China

JNJ-78436735 (Ad26.COV2.S)

Johnson&Johnson Vector vaccine USA
7 NVX-CoV2373 Novavax

Protein vaccine

(spiky protein of SARS-CoV-2 virus)

8 BBIBP-CorV Sinopharm Inactivated vaccine China
9 CoronaVac Sinovac Inactivated vaccine China
10 Covaxin Bharat Biotech Inactivated vaccine India
11 Covax-19 Vaxine Pty Ltd Protein vaccine Australia