Nineteen cases of measles have been reported to Waikato DHB officials including one which hospitalised one student and left others in isolation.

Another probable case is pending as officials grapple to keep a stronghold on the virus which is now spreading from its base in Te Awamutu to as far as Otorohanga in the south and Huntly in the north.

Eight of the 19 cases were secondary  caught from someone already contaminated  and are linked to Otorohonga College and Pokuru School, southwest of Te Awamutu.

Dr Anita Bell, medical officer of health,  said the probable case was identified in Huntly with links to Auckland.
One case has required hospitalisation.

There are several contacts in isolation.

Measles was a serious and highly infectious disease that makes people very ill for about 10 days, Ms Bell said.

''All schools are aware and have been working with Population Health (Waikato DHB's public health unit) to ensure susceptible pupils and staff are isolated where appropriate.

''Of the 20 cases, 19 are unimmunised and one has received only one of the two recommended doses of MMR vaccine. This is a testament to the effectiveness of the measles, mumps and rubella (MMR)  vaccine in protecting people who are fully immunised.

''A secondary case is a someone who has caught measles from a known confirmed case of measles. All secondary cases are unimmunised.

''Immunisation is the only 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.

- © Fairfax NZ News