The number of care home residents and staff testing positive for Covid-19 in Wales has hit its highest levels.
There were 1,507 positive tests in care homes in Wales in the most recent week, a 78% rise on the week before.
Public Health Wales said 37,026 residents and staff were tested in the week beginning 4 January across Wales.
Deputy Health and Social Services Minister Julie Morgan said avoiding care homes closing in Wales due to coronavirus has been "quite an achievement" but the situation remains "precarious".
Breaking down the care home figures, 6,466 care home residents were tested in the most recent week and 9% had positive results from NHS labs. Also, 248 care home workers tested positive, with around 96% of tests negative.
But there were another 677 positive tests results from Lighthouse labs, which do not distinguish between residents and care home staff.
All of these categories saw the highest numbers yet recorded.
Residents and staff are supposed to be tested weekly at care homes in Wales.
Care Home Inspectorate Wales also now publish separate figures around testing, which showed 137 care homes in Wales had notified one or more positive cases in staff or residents in the most recent week available and 31.8% had within the last month.
Swansea had 17 care homes which had notified at least one case in the week ending 1 January; Cardiff had 15 homes with at least one case and Bridgend was next with 13 care homes.
In evidence to the Senedd Health, Social Care and Sport Committee, Mrs Morgan said care homes have faced rising costs, such as more staffing and PPE, and falling occupancy due to higher death rates.
"By helping to fund the voids, that inevitably have been created in care homes, we've been able to keep them running, but it has been difficult.
"It is precarious keeping the care homes running, and I think we're aware of that the whole time."
The committee was considering the Welsh Government's 2021-22 draft budget.