Waikato District Health Board says there are likely to be more cases of measles, stemming from an outbreak in the Waipa district.
Letters have been sent to parents after three confirmed and seven suspected cases were identified.
The DHB says nine of the 10 patients are students at Te Awamutu College.
Only one had to be admitted to hospital.
The DHB says the students have been mixing with other people in their school holidays, so it is likely there will be more cases.
The illness begins with a fever, cough and sore eyes, before a rash appears days later.
