They said that 28 days after an effective vaccine, "a high proportion of people develop immunity.

The US drugmaker will hold trials in Idaho, Minnesota, New York, Oklahoma, Texas and Utah.

From a dry cough to a loss of sense of smell, a number of unpleasant symptoms are known to be associated with coronavirus.

While most respiratory droplets on survive on surfaces for a matter of seconds, SARS-CoV-2 droplets have been shown to survive for days.

Trial results showed that the Oxford coronavirus vaccine is 70% effective as a single dose, but up to 90% effective when given as a half dose.

Since the coronavirus outbreak was declared back in March, one of the key questions has been whether or not you can catch the virus twice.