Ministers have said they are “on track” to meet the target of getting an offer of a first dose to everyone in the UK in the top four priority groups – including all over-70s – by Monday’s deadline.

More than 15 million people in the UK have received their first dose of a Covid vaccine – just over two months since the first jab was administered.

Here are your questions answered about the future of the biggest vaccination programme in NHS history.

– How many people have been vaccinated so far?

Initially the NHS reached out to the top four priority groups, including those over the age of 70 and health and care staff, aiming to offer the jab to everyone in this group by mid-February.

On Sunday the Government said 15 million people in the UK had received their first dose.

Government data up to February 13 shows that of the 15,599,904 jabs given in the UK so far, 15,062,189 were first doses – a rise of 505,362 on the previous day.

Some 537,715 were second doses, an increase of 2,846 on figures released the previous day.

– When will they get their second dose?

The second dose of the jab can be delayed between four and 12 weeks. This means people receiving their jab today may be getting their second vaccine in May.

The people given their first jab on December 8 when the first Pfizer vaccines were administered will need to receive their second dose by March 2 to be within the 12-week window.

– What are the priority groups?

The priority list set out by the Joint Committee on Vaccination and Immunisation (JCVI) is:

1. care home residents and their carers
2. people over the age of 80 and frontline health and social care workers
3. people over the age of 75
4. people over the age of 70 and those deemed to be “clinically extremely vulnerable”
5. people over the age of 65
6. people aged 16 to 64 with underlying health conditions which put them at higher risk of serious disease and death.
7. people over the age of 60
8. people over the age of 55
9. people over the age of 50

– How many people in the top four priority groups have been vaccinated?

A total of 93.2% of residents of older adult care homes in England eligible to have their first dose of Covid-19 vaccine had received the jab up to February 7, NHS England said.

Residents are classed as eligible for the vaccine if they have not had Covid-19 in the previous 28 days.

According to NHS England figures, published on Thursday, an estimated 91.3% of people aged 80 and over in England had received their first jab up to February 7, along with 95.6% of people aged 75-79 and 74.0% of people aged 70-74.

In Wales, a total of 89.3% of people aged 80 and over had received their first dose, along with 89.9% of people aged 75-79 and 88.3% of people aged 70-74.

The latest figure for care home residents is 81.4%, and for care home workers it is 84.3%.

In Scotland, some 99% of people aged 80 or over living in the community have had their first dose, along with 99% of people aged 75-79 and 78% of people aged 70-74.

Some 94% of residents in all care homes have had their first dose. The figure for staff in older adult care homes is 91%, while the figure for staff in all care homes is 79%.

As of February 4, 100% of care homes in Northern Ireland had been visited and offered the first dose of the vaccine, while 90% of care homes had been visited and offered the second dose.

– Which priority group will be offered the jab next?

In England, people aged 65 to 69 and those who are clinically vulnerable are being invited to book their Covid-19 jab as the vaccination programme moves into a new phase on Monday.

NHS England has already sent out 1.2 million invitations to the over-65s to book an appointment, with a similar number expected to go out this week.

The Government is aiming to get an offer of a vaccine to the estimated 17 million people in the next five groups by the end of April.

– What about other adults and keyworkers?

The JCVI has not yet set out plans on who should be vaccinated beyond the top nine priority groups.

But Health Secretary Matt Hancock has pledged that all UK adults will be offered a Covid vaccine by autumn.

It is unknown whether keyworkers will be offered the jab as a priority.

The JCVI is currently discussing what the future plans should look like and expects to set out these recommendations by the end of the month.

– What will this mean for the NHS?

The impact of the vaccination programme will not be immediately felt in the NHS.

But the health service should soon start to see some big reductions in hospital admissions.

It has been estimated that giving people in the top nine priority groups the jab will reduce deaths by up to 99%.

– Can I mix with other people now I have had my jab?

Not yet. We don’t know whether or not the vaccines stop people from transmitting the virus. And questions have been raised about how protective they are against new variants.

And it takes time for the body to build up immunity after the jab – people are not protected straight away. And it is important to get the second jab to get the full protection offered by the vaccine.

– I’m over 70 and I haven’t been offered my jab yet, what should I do?

The NHS changed messaging from ‘wait until we contact you’ to ‘contact us’ to ask people to book their jab.

Over-70s can book through the website https://www.nhs.uk/conditions/coronavirus-covid-19/coronavirus-vaccination/book-coronavirus-vaccination/ or by calling 119.