Dr Marion Lyons of Public Health Wales says with 20 new cases of measles daily in Wales at the moment a death would not be surprising.
An investigation is underway on Friday to find out if a 25 year-old man from Port Tennant near Swansea died from the virus.
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Rain clipping the far north through the evening but elsewhere staying dry with some sunny spells.
Public Health Wales figures show 25 more cases of the virus have also been confirmed.
Photos taken on Saturday morning show Roald Dahl Plass strewn with empty beer bottles and discarded canisters of laughing gas.