Parents have been warned after a student at an exclusive Auckland high school was diagnosed with whooping cough.
Epsom Girls' Grammar School principal Lorraine Pound alerted parents in a notice sent this week.
The school had asked the Auckland Regional Public Health Service for advice on what to do, Pound said in the notice.
That was to provide information on the infectious bacterial disease, also known as pertussis, advice on prevention and links to more information.
Public health spokeswoman Kate Stace said in a statement to the Herald that they were experiencing "ongoing notifications" of pertussis, with an upward trend.
This year there had been 102 cases of pertussis in the Auckland region, compared to 79 over the same period last year. A quarter of the cases this year were in children aged under six.
"Pertussis is endemic (always present) in New Zealand. The group most vulnerable to pertussis is infants less than 12 months of age. Up to 80 per cent of this age group who get the illness will need hospital treatment."
The best way for them to be protected is through on-time immunisation at 6 weeks, 3 months and 5 months, and to be protected post-delivery by their mother having a pertussis booster in the last trimester of pregnancy, which is funded.
Confirmed cases of the disease are managed by a combination of isolation and antibiotics, with antibiotics also able to be prescribed for close contacts.
More information on the disease can be found here.