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.
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Tonight will remain mostly dry apart from the odd shower in places.
The mother of missing 19-year-old James Corfield from Montgomery read an emotional statement at the Royal Welsh showground this afternoon.
71-year-old Raymond Hodges was convicted of 24 charges spanning almost a decade.