Covid-19: First vaccine given in US as roll-out begins
The first jab was given to a nurse in New York, kicking off the largest vaccination in US history.
An intensive care nurse in Long Island, New York is believed to have been the first person to be given the jab.
Millions of vials of the Pfizer/BioNTech vaccine are being distributed, with 150 hospitals expected to receive doses on Monday.
The US vaccination programme aims to reach 100m people by April.
Covid-19 fatalities are nearing 300,000 in the US, which has by far the world's highest death toll.
The Pfizer/BioNTech vaccine received emergency-use authorisation from the US Food and Drug Administration (FDA) on Friday.
The roll-out of the vaccine comes as the epidemic continues to ravage the country. Deaths have been rising sharply since November and the number of people in hospital with the disease has also continued to grow steadily, with more than 109,000 people currently admitted, according to the Covid Tracking Project.
"I think it's been probably the darkest December on record here. As of this last week, Covid-19 is the leading cause of death in the US, even more than cancer and heart disease," Dr Dora Mills of MaineHealth, a network of 12 hospitals in Portland, Oregon, told the BBC
"It's a very dark season for us, but it's also extraordinary that we have a vaccine less than a year after this virus has emerged. If the efficacy and safety data hold up, this is likely [to be] the greatest public health and scientific achievement of our lifetime."