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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All primary and secondary schools in Wales have been categorised in a new colour-coded system. Is your school green or red?
A yellow warning for snow and ice on Thursday night and Friday has been issued.
Some wintry showers and staying windy with a significant wind chill and widespread frost developing