Medical experts say there's been a four-fold rise in the number of Welsh cases of measles this year, compared to the previous 12 months.
From January to June there were 61 cases.
Public Health Wales says raising MMR vaccination rates is the key to tackling the problem.
Incidences of whooping cough were also up.
More top news
More than half of adults in Wales have experienced harm or a negative experience because of someone else's drinking, a new report has found.
A major review will be published later this morning into student finance and higher education in Wales.
Dull and damp for much of Wales as we start the day, with drier and brighter weather on the way this afternoon.