India's drug regulator has granted emergency use approval for Zydus Cadila's Covid-19 vaccine, the world's first DNA shot against the coronavirus, in adults and children aged 12 years and above.

The vaccine, ZyCoV-D, uses a section of genetic material from the virus that gives instructions as either DNA or RNA to make the specific protein that the immune system recognises and responds to.

Unlike most Covid-19 vaccines, which need two doses or even a single dose, ZyCoV-D is administered in three doses.