The autumn and winter vaccination programme for flu and Covid is now under way, with the main programme running until mid-December.
NHS Shetland says the newly-identified Covid variant, BA.2.86, means people aged 75 and over will be seen sooner than first anticipated.
Those who have weakened immune systems or live in care homes will also now be amongst the first to be invited for their vaccinations.
These groups of people were initially due to receive their vaccinations from mid-October, but as a precautionary measure, those at the highest risk of becoming seriously ill from flu and Covid have now been brought forward.
School flu clinics have also started and will shortly be followed by flu clinics for pre-school children.
Health and social care workers are also being offered their flu and Covid vaccinations.
Those eligible for flu and/or Covid vaccinations may be contacted by letter, or via telephone or potentially, text or email if they have opted in for this service.
Later in the programme, people will be able to use the booking portal to book and change appointments.
There is also an option to phone the national helpline or the local vaccination team.
Because there is no longer a vaccination centre at Gilbertson Park Games Hall, clinics will run in healthcare settings along with schools and care homes.
Those unable to travel to a clinic will be given vaccinations at home.
The NHS says people living in Unst, Yell and Whalsay, and those registered with the Hillswick, Walls and Bixter practices, will be invited to attend clinics at their own health centre.
Meanwhile, people registered with Brae, Scalloway and Levenwick may be invited to their health centre, or to a Lerwick clinic.
Some people may be asked to come to clinics at the Gilbert Bain Hospital.
As in previous years, walk-in appointments will be available in some clinics for those who are eligible for the vaccinations.
The NHS says these will be publicised later in the programme.