Covid: NHS pressure fears over end of firebreak lockdown
Health boards fear the easing of lockdown in Wales could put more pressure on the NHS, unless new rules are followed.
Darren Hughes, director of the Welsh NHS Confederation, said staff were often forced to take time off work in areas where Covid-19 cases had spiked.
It comes as figures suggest hundreds of thousands of sick days were lost to the Welsh NHS due to the pandemic.
He urged people to stick to rules from Monday to stop care being compromised.
"We've all had to make changes to our personal lives and it's difficult… but we also need to ensure those staff on the front line are able to do their jobs and protect us and our families," Mr Hughes said.
The Royal College of Nursing in Wales said an increasing number of staff were accessing mental health support, including for post-traumatic stress disorder (PTSD), due to the pandemic.
The body, which represents nurses, health care assistants, midwifes and student nurses, said at the start, most absences related to staff falling sick or having to isolate with coronavirus.
Associate Director Nicky Hughes said the knock-on psychological effects were now becoming clearer.
"Some of our staff have been patients themselves, and been in intensive care or critical care," she said.
"We are seeing both patients, and members of staff - nurses, healthcare support workers - who have experienced PTSD."
On Monday, pubs, bars, restaurants, gyms, salons, and non-essential shops will be allowed to reopen again as a Wales-wide 17-day lockdown ends.
During the lockdown people were told to "stay home" and to only travel for essential reasons such as to buy food and medication, and to deliver care.
As the lockdown ends, many will be able to travel outside their own county for the first time in weeks, as a new set of national rules replaces local lockdown measures.
First Minister Mark Drakeford has urged people to do the "minimum which rules allow" from Monday, and to ask themselves if things are "necessary" before doing them.
But with case rates remaining high in some Valleys counties, including in Merthyr Tydfil where 610.01 cases have been confirmed per 100,000 people in the last seven days, Plaid Cymru and the Conservatives have raised concerns about easing lockdown restrictions.
BBC Wales asked all health boards in Wales and the ambulance service for data on sick leave which was taken as a result of Covid-19.
The figures include those who was shielding, isolating because of their own symptoms, or isolating because of contact with a positive case.
Across the country about 270,000 days were lost between March and August, the Freedom of Information request revealed. The Cardiff and Vale health board provided figures suggesting more than a quarter of all sick leave was related to Covid-19.
Ms Hughes urged people to follow the rules and protect NHS services from further pressure once the lockdown ends. "Staff are under pressure in terms of being able to deliver what they need for patients," he said.
"But we're also seeing where there is an outbreak in a community, a large number of staff are hit by it and so their ability to provide care on the front line is really hit."
Ms Hughes urged people to act responsibility to protect staff, who were already facing normal winter pressures. "We've got to get our heads back into that space of what I do as a person, my actions are going to have a direct influence on other people around me... for not only the NHS, but the other emergency services that are out there in care homes and places like that, as well," she said.
BBC Wales Investigates: The hidden cost of Covid is on BBC One Wales on Monday 9 November at 20:30 GMT