Another three people have died with coronavirus following outbreaks at hospitals.
The Royal Glamorgan Hospital in Llantrisant, Prince Charles Hospital in Merthyr Tydfil and the Princess of Wales Hospital in Bridgend have each reported the death of a patient.
It brings the total number who have died at the three hospitals to 26.
Cwm Taf Morgannwg health board said the outbreak was being taken "extremely seriously."
To date, 129 cases have been linked to the outbreak at the Royal Glamorgan Hospital.
Seventeen cases have been linked to Prince Charles Hospital with 16 at the Princess of Wales Hospital.
Medical director Nick Lyons said the health board was closely monitoring the cases in conjunction with Public Health Wales.
"The safety of our patients and staff remains our first priority and immediate measures to contain the spread of the virus have been put in place.
"We are taking the outbreaks extremely seriously and the stringent and robust mitigating actions which have been taken across our sites are being closely observed.
"However given the nature of coronavirus, there is an inevitable time delay in when we will see the positive impact of these measures."
Dr Lyons apologised for the concern caused to families and the community and warned infections continued to rise in the community.
He urged people to "take seriously their responsibilities" to help stop Covd-19 spreading.