An effective vaccine against coronavirus has long been seen as a way out of the pandemic - and a return to normal life.
Three vaccines - Pfizer / BioNtech, Oxford / AstraZeneca and Moderna - have been approved by the Medicines and Healthcare products Regulatory Agency (MHRA).
The task of rolling the vaccines out, however, remains a complicated one amid a third national lockdown and a second wave of the virus, which is threatening to overwhelm the NHS.
Calls to speed up the vaccine rollout were answered by Prime Minister Boris Johnson who sought the help of the British Army in what he described as "an unprecedented national effort" to defeat the virus.
But how effective has it been so far?
How many people in England have received a first vaccination?
As of 15 February, more than 13 million - 13,082,669 - people have received the first dose of Covid-19 vaccine in England, according to UK government statistics.
How many people in England have received a second vaccination?
Just shy of half a million - 492,576 - people have received a second dose of Covid-19 vaccine in England, as of 15 February, according to UK government statistics.
Which vaccines are people in England receiving?
People who have been vaccinated for coronavirus have received either the Pfizer or the Oxford jab.
The Pfizer / BioNtech jab was the first vaccine to be approved by UK regulator MHRA and began to be administered on 8 December 2020.
The Oxford / AstraZeneca jab was the second vaccine to be given the green light by the MHRA and began its rollout on 4 January 2021.
The third vaccine to have been approved for use in the UK is the Moderna available, which will become available in the Spring.
How will the vaccines be rolled out?
The government surpassed its target of vaccinating 15 million of the most vulnerable people to the virus in the UK by 15 February.
Mr Johnson set the target as he plunged England into a third national lockdown on 4 January to limit the spread of the virus.
The number of vaccines administered day to day fluctuates depending on supply but the government remains confident of hitting its target.
On top of 1,000 GP sites, 200 community pharmacies and 223 hospital hubs, a further 17 mass vaccination centres have been set up for jabs to be administered.
When will I receive a vaccine?
The Department of Health has detailed groups to be given priority in receiving the vaccine by the Spring, which are thought to account to 90-99 percent of those at risk of dying from Covid-19.
It plans to offer a first vaccine dose to care home residents and care home staff, frontline health and social care workers, over 75s and the clinically extremely vulnerable before 15 February.
Between the end of February and April the remaining priority groups, a further 17.2 million people, aged 50-70 and 16-64 year olds with underlying health conditions will also receive a first dose.
The remaining adult population, roughly 21 million, will then be offered a first dose of the vaccine by the Autumn as the programme expands.