A further 14 cases of Covid-19 have been confirmed on Shetland overnight.
Health bosses confirmed more than a dozen people had contracted the virus, taking the total number of infections on the island to 72.
More than 300 people across the island are currently self-isolating following the outbreak which has been linked to a cluster on the north mainland.
Dr Susan Laidlaw, consultant in public health for NHS Shetland spoke of her concern that many positive cases are not presenting with symptoms but may have unknowingly been moving around the community while infectious.
She said: “We are hearing people say that they have had a new cough but didn’t get a test because they didn’t think it was a ‘Covid’ cough. Any new continuous cough should be a prompt to get a test, along with a high temperature or loss/change in taste or smell.
“We are still fighting back a wave of infections. The simplest guidance at the moment is to stay at home with your own household as far as possible and avoid meeting others as much as you can. If you do come into contact with others then remember FACTS.”
Libraries on the island have been closed and residents have been urged not to board inter-island ferries as cases continue to rise.
The outbreak is the biggest reported by health officials since the pandemic first gripped the island.
Officials confirmed the majority of infections occurred before and during the festive period when Shetland was placed in level one and rules were relaxed to facilitate socialising on Christmas Day.
Shetland currently remains under tier three restrictions as mainland Scotland resides under tier four.
Dr Laidlaw said that those who are isolating because they are positive, or a contact of someone who is positive, would often receive an automatically generated text messages telling them how long to isolate.
She added: “For cases this will depend on when their symptoms started (or when they had a test if not symptoms) and for contacts it will depend on when they last had contact with an infectious person.
“However, there are a number of people who are contacts of several others on different dates which means that they may get conflicting text messages.
“Please, always go by the latest date.”
