[WN] - Globally, the World Health Organisation (WHO) is tracking around 140 candidates vaccines, of which around two dozen are in various phases of human clinical trials.

The world is eagerly waiting for a vaccine to combat the coronavirus which has ravaged through the world resulting in more than six lakh deaths.

There was a buzz in the medical fraternity after the editor of the medical journal The Lancet announced on Twitter that he is going to announce the results of the Oxford Covid-19 vaccine study.

“Tomorrow. Vaccines. Just saying,” Richard Horton tweeted on Sunday.

Globally, the World Health Organisation (WHO) is tracking around 140 candidates vaccines, of which around two dozen are in various phases of human clinical trials.

Chinese company Sinovac Biotech is moving into phase III trials in Brazil while the University of Oxford/AstraZeneca is in a combined phase II/III trial in the UK and has recently gone into phase III trials in South Africa and Brazil.

Among other leading players, German firm BioNTech is collaborating with pharma major Pfizer to develop a vaccine for Covid-19. The companies have received fast track designation from the US Food and Drug Administration (USFDA) for two investigational vaccine candidates being developed to help protect against SarS-CoV-2.

Vaccines typically provide the immune system with harmless copies of an antigen: A portion of the surface of a bacterium or virus that the immune system recognizes as foreign. A vaccine may also provide a non-active version of a toxin - a poison produced by a bacterium - so that the body can devise a defense against it.

They must follow higher safety standards than other drugs because they are given to millions of healthy people.

Vaccine testing is a four-stage process - pre-clinical testing on animals, phase I clinical testing on a small group of people to determine its safety and to learn more about the immune response it provokes, phase II trials are expanded safety trials, and phase III testing is done by administering it to thousands of people to confirm its efficacy.