Abertawe Bro Morgannwg University Health Board says many of the people it has been treating have cardiac problems or have suffered a stroke. Many are over the age of 85.
The health board says it has brought in extra staff, and put on extra beds, to deal to with its A&E departments being exceptionally busy.
It says most routine operations have been postponed.
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Not a bad day today, with warm sunshine! Unless you live in the south, in which case you may have some sharp showers to deal with!
A generally dry night with clear spells in the north. Showers will push in to the south by the early hours!
Finley Thomas was a "lovely, happy beautiful baby" and changed in the months leading up to his death, a court has heard.