EVERYONE over 50 in Scotland will be vaccinated against Covid by the beginning of May, Nicola Sturgeon has said.

The First Minister told MSPs she hoped that the immunisation programme could be accelerated further if supplies allow.

To date, more than 100,000 people in Scotland - mostly care home residents, staff and frontline NHS workers - have been given their first dose using the Pfizer-BioNTech vaccine.

This is projected to rise to more than 900,000 by the end of January, with more 440,000 people expected to receive the AstraZeneca-Oxford vaccine now being rolled out to the over-80s.

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Ms Sturgeon said the Scottish Government does not yet “have certainty of supply schedules beyond January” but added: “By early May, everyone over 50 and people under 50 with underlying conditions will have received at least the first dose of vaccine.

“And that is everyone who is on the JCVI [the UK Joint Committee on Vaccination and Immunisation] priority list, which comprises more than two and a half million people.

“Once everyone on the priority list has been vaccinated we will start vaccinating the rest of the population, in parallel with completing second doses for those on the priority list.”

People will be given the same vaccine for their first and second doses, rather than mixing the Pfizer and Oxford vaccines, said Ms Sturgeon.

Both vaccines are now being rolled out in two doses, 12 weeks apart - instead of 21 days - to maximise the number of people protected. It comes amid alarm over the UK’s escalating infections crisis and urgent pressure to reduce the number of people developing Covid - the disease caused by the coronavirus infection - in order to stem hospital admissions and deaths.

In a statement on December 31, the JCVI said evidence indicates that the Pfizer vaccine is 89% effective at preventing symptomatic Covid infection 15 days after the first dose, while the Oxford vaccine was 73% effective after 22 days with “high protection against hospitalisation...for a duration of 12 weeks”.

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Stephen Evans, a professor of pharmaco-epidemiology at the London School of Hygiene & Tropical Medicine, said it was impossible to say what was “optimal” since the clinical trials had not specifically studied the effects of dose spacing.

He said: “We have to utilise what we know from science generally. We know that vaccinating only half of a vulnerable population will lead to a notable increase in cases of Covid, with all that entails including deaths.

“When resources of doses and people to vaccinate are limited, then vaccinating more people with potentially less efficacy is demonstrably better than a fuller efficacy in only half.”

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Dialysis patient Brian Pinker, 82, was the first person in the world to be immunised outside of clinical trials using the Oxford vaccine, which was approved by UK regulators last week. He was given the jag at Oxford University Hospital, close to where the vaccine was developed.

In Tayside, James Shaw , 82, from Dundee, said he was “delighted” to be one of the first people in Scotland to given the Oxford vaccine, along with his 82-year-old wife, Malita.

Mr Shaw , who received his inoculation at Lochee health centre, said: “ I have asthma and bronchitis and I have been desperate to have it so I am really pleased to be one of the first to be getting it.

“I know it takes a little while for the vaccine to work but after today I know that I will feel a bit less worried about going out. I will still be very careful and avoid busy places but knowing I have been vaccinated will really help me.”

Scotland will ultimately receive more than eight million doses of the Oxford vaccine, from the UK total order of 100 million.

Health Secretary Jeane Freeman said: “The priority now is to vaccinate as many people with their first dose as quickly as possible, working through that priority list and the advice that the second dose for both vaccines can be given up to 12 weeks after the first means we can maximise this protection quicker than planned. The second dose remains critical for longer term protection and to complete the course.”