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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Leaders of Wales, Scotland and Northern Ireland meet in Downing Street for talks with Theresa May ahead of Britain's departure from the EU
The prime minister has offered Scotland, Wales and Northern Ireland a "direct line" to Brexit Secretary David Davis.
22-year-old Ify Iwobi has been making music since the age of seven.