US Government’s Pfizer COVID-19 vaccine approval starts rollout of mass-vaccination program. Here’s what we know

The US Government’s approval of a COVID-19 vaccine will set off the largest vaccination campaign in the country’s history.

The Food and Drug Administration (FDA) has given the green light for the emergency use of a vaccine developed by Pfizer and BioNTech and US President Donald Trump said the first shots would be administered “in less than 24 hours”.

It comes at a time when the United States has recorded around 15.5 million infections and close to 300,000 deaths from the virus.

But it’s not a silver bullet, just yet.

Logistical challenges, supply issues and scepticism about the inoculations will play a part in the rollout of the vaccine, which is expected to…