THE two Covid vaccines will not be mixed in Scotland unless it is unclear which vaccine was given in the first dose, Nicola Sturgeon has confirmed.

Addressing MSPs, the First Minister said mixing the Pfizer-BioNTech the Oxford-AstraZeneca jabs is “not our policy in Scotland" unless there are "exceptional circumstances such as we don’t know what vaccine was given in the first dose".

Both vaccines require two doses which are now to be administered 12 weeks apart.

READ MORE: Scottish medical experts back delay of second Covid vaccine dose

Confusion around the vaccine roll-out mounted at the weekend after Dr Mary Ramsay, Head of Immunisations at Public Health England, said that people should receive a second dose of the same vaccine.

She said: “We do not recommend mixing the Covid-19 vaccines – if your first dose is the Pfizer vaccine, you should not be given the AstraZeneca vaccine for your second dose and vice versa.”

Medical professionals have also questioned the scientific reason for mixing injections. Allyson Pollock, co-director of Newcastle University Centre of Excellence in Regulatory Sciences and a former member of Independent Sage, said: “We need to see the data and basis for this decision.”

John Moore, vaccine expert at Cornell University in America, added there is “no data on this idea whatsoever” and claimed the UK “seem to have abandoned science completely now and are just trying to guess their way out of a mess”.

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The UK-wide Joint Committee on Vaccination and Immunisation (JCVI) is understood to have updated advice on mixing vaccines on December 31.

The FM said everyone over 50 in Scotland will have been vaccinated against Covid by the beginning of May.

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

Speaking as the rollout of the AstraZeneca-Oxford vaccine got underway in Scotland for those over 80 in the community, Sturgeon said that more than 100,000 people have been given their first dose so far of the Pfizer-BioNTech vaccine.

Both vaccines are now being rolled out in two doses, 12 weeks apart - instead of 21 days - in order to maximise the number of people protected with a first dose.

Sturgeon said she expects that over 900,000 people will have received an initial vaccination by the end of January, with an even split between the number given the Pfizer vaccine and the number given the Oxford vaccine.

The Pfizer vaccine - which has to be kept at ultra-low temperatures - has been targeted to care home residents, care home staff, and frontline NHS workers.

James Shaw, 82, from Dundee, was among the first to get the jab.

He was vaccinated at the Lochee Health and Community Care Centre in the city alongside his wife Malita, also 82.

READ MORE: 'Expectation' that all over 50s in Scotland vaccinated by early May

NHS Tayside is rolling out the vaccine through GP practices in the community and will also vaccinate elderly residents and staff in care homes.

Shaw said: “My wife and I are delighted to be receiving this vaccination.

“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.

“All of my friends have said they are going to have the vaccine when it is their turn and I would encourage everyone who is offered this vaccination to take it.”

The UK has secured access to 100 million doses of the AstraZeneca/Oxford University vaccine, enough for most of the population.

Scotland will get a proportionate 8.2% of the jabs.

The Scottish Government said its priority is to vaccinate as many people with their first dose as quickly as possible, with the second dose to be given within 12 weeks.

The order in which people will received the vaccine is determined by the Joint Committee on Vaccination and Immunisation.

It will be given first to care home residents and their carers, people over the age of 80 and frontline health and social care workers.

The programme will then be rolled out to the rest of the population, starting with people aged 75 to 79, followed next by those aged 70-74 and the clinically extremely vulnerable.

Health Secretary Jeane Freeman said: “Seeing the Astrazeneca vaccine being administered to people in the community aged over 80 is a good way to start the New Year and I’m grateful to everyone in NHS Tayside and boards across the country for their work in preparing for the delivery of this newest vaccine.

“Oxford AstraZeneca has the advantage of being much easier to store and transport, which means it is easier to administer in local settings. We are also expecting to receive it in significantly larger quantities than the Pfizer vaccine.

“When it is your turn to be vaccinated you will be contacted by your local health board and I urge you to please take up the offer.”

NHS Tayside associate director of public health Dr Daniel Chandler, the immunisations co-ordinator who is overseeing the Covid-19 vaccine rollout in the health board, said: “The efforts of our vaccination teams have been amazing and it is testament to a real whole team approach that sees the first over-80s in the general population have their jabs today in Tayside.

“The availability and mobility of the Oxford Astrazeneca vaccine gives us the opportunity to start to roll out the biggest vaccine programme that the UK has ever seen across our communities.

“Over-80s are the first priority group and patients will be contacted directly to attend a vaccination session.”