The United States said it authorized the use of Pfizer Inc’s COVID-19 vaccine on Friday, with the first inoculations expected within days, marking a turning point in a country where the pandemic has killed more than 295,000 people.

The US Food and Drug Administration (FDA) granted an emergency use authorization for the vaccine, developed with German partner BioNTech, which was shown to be 95% effective in preventing the disease in a late-stage trial. It said the vaccine can be given to people aged 16 and older.

Healthcare workers and elderly people in long-term care facilities are expected to be the main recipients of a first round of 2.9 million doses this month.

BioNTech Chief Executive Ugur Sahin said the vaccine “will help to save lives across the United States and could accelerate a return to normality.”

US health authorities, shipping services, hospitals and pharmacies have been readying a nationwide inoculation campaign. Pfizer said it would start shipping immediately and state public health systems have been planning to begin shots as early as Monday.

The government plans to accelerate vaccinations in the coming weeks and months, especially if a second vaccine from Moderna Inc is quickly approved. An advisory group to the US Centers for Disease Control and Prevention will meet on Saturday to make crucial recommendations about whether some groups such as pregnant women and 16-year-olds should be immunized.

The authorization comes as cases are surging in the United States, with thousands of death per day, while hospital intensive care units across the country are nearing capacity, threatening to overwhelm healthcare systems.

“It is one step in a sequence of steps that will bring this pandemic to an end,” said Amesh Adalja, a senior scholar at the Johns Hopkins Center for Health Security.

He added: “A lot of people will be infected, a lot will be hospitalized and a lot will die before the vaccine is able to have a meaningful impact on spread.”

The Pfizer/BioNTech vaccine was first approved in Britain earlier this month, and UK residents began receiving the shots on Tuesday. Canada also authorized the vaccine and expects to start inoculations next week. Mexico, Bahrain and Saudi Arabia have also approved the Pfizer vaccine.