Parents with children at schools across the Tees Valley are set to receive letters and consent forms over the next few days urging them to take up the offer of the MMR vaccination.
The move follows an outbreak of measles across the North East and is being carried out by the Tees Outbreak Control team.
The team are now introducing a school-based MMR vaccination campaign - to be offered to all children who have yet to be vaccinated against the illness.
The vaccinations will take place across the next few weeks.
"Measles is a highly infectious disease and people can feel very poorly when they have contracted it. 17 per cent of the current cases have required hospital treatment and the disease can lead to rare yet serious complications.
"I would therefore urge all parents to get their child vaccinated through the school based campaign if they have not been immunised already.
"MMR is a safe and highly effective vaccination which protects against measles as well as mumps and rubella."
"I'm very pleased and reassured to see arrangements between the local authorities, NHS England, Public Health North East and the School Nursing Teams working effectively to tackle this outbreak.
"I would like to urge all parents to listen to Professor Kelly's message and make sure their children are vaccinated."
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