What is mRNA Technology used in COVID-19 vaccines for the first time?

On November 16, 2020, Moderna, a US Biotech firm announced that its COVID-19 vaccines are 94.5% effective. The announcement comes in days after Pfizer released results showing 90% effectiveness in its own vaccine. Both the companies use mRNA technology in their vaccines. This is the first time the mRNA technology is being used to create vaccines.

How mRNA vaccines work?


The mRNA vaccine forces the healthy cells of the human body to generate copies of viral proteins. This in turn prompts the immune system to create antibodies to fight against the spike proteins (COVID-19).


The mRNA sequence generated by the scientists using the technology has been coded with spike protein of COVID-19 virus. This RNA sequence is laid in a lipid coating and is injected into human body. As it is injected and arrives inside the human body, the cells read the information in mRNA sequence. They then begin to generate copies of the viral proteins. This in turn forces the immune system to produce antibodies against the spike proteins. Thus, the individual is protected when a real virus enters the body. It is to be noted that the COVID-19 enters the human body through its spike proteins. Thus, by preventing the spike proteins from entering the human body, the entire virus is prevented.

Other Vaccine Categories

While the vaccines of Moderna and Pfizer belong to replicating viral vector category, there are other types such as non-replicating viral vector category. For instance, the vaccines of AstraZeneca and Oxford University belong to non-replicating viral vector category. These vaccines use a different virus. A weakened version of Adenovirus (a common cold virus) is used to carry the spike proteins. Adenovirus usually infect Chimpanzees. The Moderna and Pfizer have developed the vaccine by genetically modifying the Adenovirus.

They are inactivated COVID-19 vaccines that were made by killing COVID-19 virus. After killing, the virus loses its capability to replicate or infect. However, their proteins are intact (spike protein in the case of COVID-19). These proteins are used to create the vaccine. These are DNA vaccines.


Leave a Reply