Covid in Scotland
Almost a third of younger adults are still unvaccinated despite all over-18s being offered a first dose vaccine appointment by the end of Sunday.
Health Secretary Humza Yousaf said some had re-arranged appointments and would receive the jab shortly.
National clinical director Prof Jason Leitch said last week that uptake of the vaccine among 18-29 year olds had been slower than for other age groups.
It is hoped all adults will have been offered a second dose by 12 September.
People in the 18-29 age range have been the last group to be offered a coronavirus vaccine.
Last month First Minister Nicola Sturgeon said all adults would have had a vaccine appointment scheduled by 18 July, two weeks earlier than previously planned.
But while uptake of the vaccine has been very high in Scotland overall, it appears to have been slower for younger adults.
The most recent figures, published by Public Health Scotland on Saturday, showed that 31.6% had still not had their first dose of a vaccine, which suggests more than 260,000 younger adults are still unvaccinated.
Only a fifth (20.2%) of this age group have had both doses.
Since May, the official advice has been that under-40s should be offered an alternative to the Oxford-AstraZeneca vaccine, after a link with rare blood clots was identified.
Mr Yousaf said everyone who had taken up their offer of a vaccine was "playing their part in helping us out of the pandemic", and urged anyone who had not yet come forward to do so now.
He added: "All of the evidence says that the vaccines are working as we continue to battle the faster-transmitting Delta variant, which is now dominant, so I urge everyone to take advantage of the vaccination programme which is open to every adult in Scotland.
"We have made getting a vaccination easier than ever - head to one of the drop-in clinics being offered across the country or, if you prefer, book an appointment online at NHS Inform."
On Saturday, the closure of the mass vaccination hub at the Hydro in Glasgow, due later on Sunday, was criticised by opposition politicians, who said it should remain open while there were still vaccines to be administered.
The Scottish government said the venue would be handed back so preparations could be made for the COP26 climate change conference, and appointments will be offered at alternative clinics.
Official figures published on Saturday showed that 3,970,026 people have received the first dose of Covid vaccine and 2,954,776 have had their second dose.
The landmark of all adults being offered a vaccine comes ahead of Scotland's Covid rules easing further on Monday, when the whole country will be in level zero.
It will mean up to eight people from up to four households can meet indoors at home, and up to 10 people from up to four households can meet in a public indoor space.
Up to 15 people from up to 15 households can meet outdoors - whether in a private garden or public place.
However, masks will continue to be compulsory on public transport and in shops "for some time" in Scotland, and for now people are still being advised to work from home.
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