There are now five Waikato schools with confirmed cases of measles.
While the spread is still largely associated with Fraser High School; Hamilton Boys' High School, Frankton Primary School, Nga Taiatea Wharekura and Raglan Area School also have confirmed cases.
"The schools have all been informed and are taking the necessary action to prevent further transmission within the schools," said Waikato District Health Board medical officer of health Dr Anita Bell.
Waikato DHB's Population Health service has to date (27 June 2014) confirmed 84 measles cases in Hamilton in recent weeks.
Twenty-one of these cases are household contacts of confirmed cases and had already been placed in quarantine before they were unwell.
Six cases have been hospitalised but are now well.
Of the 84 cases, only four have been immunised with two documented doses of the measles, mumps and Rubella (MMR) vaccine and four cases have received one documented dose of MMR.
Approximately, 40 cases with clinical illness like measles have been investigated and were found not to have measles.
Population Health is investigating about another 15 suspected cases from throughout the city.
"It's important that with the spread outside of the Fraser High School community, that people make themselves aware of the signs and symptoms of measles and to check their child's immunity status," said Waikato DHB medical officer of health Dr Anita Bell.
"Information has been circulated regarding the increase in cases to all schools, early child care centres and general practice."
People who are regarded as not immune to measles are:
• People younger than 45 years old (born after 01 January 1969) who have not had two doses of the measles-mumps-rubella (MMR) vaccine or have not had a laboratory confirmed positive measles result
• Children over four years old who have not received their second dose of MMR
• Infants under the age of 15 months who have not received their first routine dose of MMR vaccine. They are susceptible and rely on everyone else to be immune so that measles does not spread to them
"Measles can be a very serious illness, with one in three sufferers experiencing complications such as ear infections, pneumonia, bronchitis or diarrhoea," said Dr Bell.
"While one in 10 on average requires hospitalisation, admission rates in this outbreak have been higher."
She reiterated that immunisation is the best protection from this potentially serious disease.
"Immunisation protects not only the individual, but also blocks the spread of this disease within our communities."
Unimmunised people who have had contact with a person with measles, will normally be advised to stay at home and away from all public places, school or work for 14 days after their contact.
"Anyone born before 1969 or who has received two doses of MMR can reasonably assume they are already immune."
If families suspect someone has measles they should call their doctor, where possible, before visiting to avoid spreading the disease while waiting.
Measles is spread by tiny droplets in the air and is one of the few diseases that can spread so easily to those nearby.
Dr Bell says anyone displaying symptoms of measles, which include fever, cough, blocked nose, sore red eyes, should immediately telephone their doctor or Healthline on 0800 611 116 for advice.
Visit www.waikatodhb.health.nz/measles for Waikato measles information.
What is measles?
• Measles is a highly infectious viral disease that can be serious.
• It is spread from person to person through the air by breathing, sneezing or coughing. Just being in the same room as someone with measles can lead to infection if you are not immune.
Who is at risk of measles infection?
People are at risk of getting measles if they are not immune to measles. People who are regarded as not immune to measles are:
• People younger than 45 years old (born after 01 January 1969) who have not had two doses of the measles-mumps-rubella (MMR) vaccine
• Infants under the age of 15 months who have not received their first routine dose of MMR vaccine. They are susceptible and rely on everyone else to be immune so that measles does not spread to them.
• Children over four years old who have not received their second dose of MMR.
What should you do?
• Ensure you are up to date with your immunisations.
• If you are not immune it is important to be aware of the symptoms of measles. The early symptoms of measles are fever, runny nose, sore red eyes and cough.
• After 3-5 days a red, blotchy rash appears on the face and head and then spreads down the body.
If you develop symptoms of measles:
• Stay at home and away from public places (such as sports events, gatherings, parties, school, work, child care, shopping centres, public transport and so on).
• See your doctor as soon as possible so a diagnosis can be confirmed. However, phone the surgery ahead to alert them of your symptoms and to allow them to make arrangements to assess you safely and without infecting other people.
• If you are unable to visit your GP phone Healthline on 0800 611 116.