Up to 80,000 people across Northern Ireland who are shielding from Covid-19 are likely to have to continue to follow the strict lockdown measures beyond the initial 12-week recommendation, it has been warned.
The Executive published its much-anticipated lockdown exit proposals, but those in the most at-risk groups will probably have to remain isolated in their homes "for the foreseeable future".
Experts have warned it is highly unlikely that those who are shielding, which includes transplant and cancer patients and people living with severe chronic obstructive pulmonary disease (COPD), will be able to follow the exit strategy at the same rate as the rest of the population.
It means that even when family visits are permitted, anyone who is shielding will not be able to take part.
Tens of thousands of people will also be unable to return to work, while children of people who are shielding may not be able to attend school, even if classes recommence.
Dr Connor Bamford, a virologist from Queen's University Belfast, said the future for people who are shielding remains uncertain. He has called for more clarity to ensure that people do not put themselves at risk.
"I can see the 12-week shielding period being extended," he said.
"It's important to protect the vulnerable and that won't change for the foreseeable future.
"I think one of the ways it is going to be possible to lift restrictions from people who are shielding is to really reduce the presence of the virus in the community.
"It's hard to think how we could increase social distancing, so we need to increase testing and contact tracing in order to do that.
"The guidance is very limited, there really should be more explanation around shielding and testing in particular.
"The roadmap lacks details and we need more information about what is going to be happening moving forward."
Dr Bamford said the ideal scenario would see people who are shielding being allowed out of their homes when a comprehensive testing and tracing policy is put in place identifying when areas are Covid-free.
However, testing and contact tracing would identify any outbreaks and alert those who are shielding to the presence of the virus in their community, meaning that they could take additional precautions to keep themselves safe.
This may include removing children from school or sending them to live elsewhere for the duration of an outbreak so they can continue to go to school when a parent is considered high risk.
Dr Tom Black, chair of the British Medical Association's Northern Ireland council, said: "Until we have a reduced number of cases in the community, people who are shielding are still at risk.
"As a result, the sensible thing to do is to continue to shield patients.
"The R number would need to be considerably lower than it currently is at the moment (0.79), it would need to go lower than it was before we told patients to shield, and we need testing and contact tracing to allow us to track what is going on in the community."
GPs across the UK were asked to identify the most at risk patients and send them letters telling them to shield for at least 12 weeks.
Initially 40,000 people here were sent a letter. It was later extended to 80,000.
Anyone who is shielding has been advised to completely isolate themselves from anyone who may be coming into contact with the virus, including anyone in their household such as spouses and children. This includes sleeping and eating in a separate room and using a different bathroom.
The Department of Health was asked whether it has considered extending the length of time it asks people to shield or what measures will be put in place to protect the most at-risk if shielding is not continued beyond the original 12-week period.
A spokeswoman from the Department of Health said: "There is currently no change to the advice contained in the shielding letter."