Covid-19: How do inactivated vaccines work?


INACTIVATED vaccines use a pathogen that has been modified so that it cannot replicate to stimulate our immune system. They are safe because they cannot cause disease. However, booster doses may be necessary.

All data and statistics are based on publicly available data at the time of publication. Some information may be out of date. Visit our coronavirus hub and follow our live updates page for the most recent information on the Covid-19 pandemic.

Vaccines that make use of the entire pathogenic virus are called whole virus vaccines. Using a pathogen or a part of a pathogen in a vaccine is a traditional approach, and most vaccines available today work this way.

In contrast, the Covid-19 mRNA vaccines by Pfizer-BioNTech and Moderna use genetic material that is chemically synthesized in a laboratory to teach our immune system how to fight off future infections with the SARS-CoV-2 virus.

There are two different types of whole virus vaccines: live attenuated and inactivated.
Live attenuated vaccines use a weakened form of a pathogen. These elicit strong immune responses but are not suitable for people with a weakened immune system.
In an inactivated vaccine, the pathogen is killed or modified in such a way that it is unable to replicate. It cannot cause disease and is, therefore, suitable for those with a compromised immune system.

The inactivation step usually involves heat, radiation, or chemicals to destroy the pathogen’s genetic material, which stops it from replicating.
Inactivated vaccines can trigger a strong immune reaction, but it is usually not as strong as the reaction that live attenuated vaccines can produce. Due to this, a person may need booster shots to ensure ongoing protection.
The Covid-19 vaccines that Sinovac, Sinopharm, and Bharat Biotech have developed are inactivated vacci-nes.

Other examples of inactivated vaccines include those against polio, hepatitis A, and rabies.
The Chinese state-owned biopharmaceutical company Sinopharm developed the inactivated Covid-19 vaccine called BBIBP-CorV in collaboration with the Beijing Institute of Biological Products.

The researchers studied SARS-CoV-2 samples from three people and chose one as the basis for their vaccine. They expanded the virus in cells and then used a chemical called beta-propiolactone to inactivate it. This chemical modifies the virus’s genetic material, leaving it unable to replicate.

Previous articleUS-Pak scholarship programme celebrates 16th anniversary
Next articleBP plunges into $20.3b annual loss on virus