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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ITV Cymru Wales today announces its extensive line up of coverage of General Election 2015 across news, programmes and online.
Wales captain Ashley Williams says summer holidays for the squad have been put on hold as qualifying for Euro 2016 takes precedence.
Two friends have died after taking suspected "legal highs" at the same house party.