Parents who vaccinate their children against meningitis can't be complacent because it doesn't protect against all strains of the virus, says Wellington's medical officer of health.
Wellington schoolgirl Amanda Crook-Barker died earlier this week within hours of showing meningococcal symptoms.
The 12-year-old is the third fatal meningococcal case this year.
Since then there has been a rush to immunise against the illness.
But Dr Annette Nesdale said people must continue to be vigilant because the vaccine did not protect against all strains of the illness.
"So say your child has been vaccinated against group C of the disease, group B is also common in New Zealand.''
Dr Nesdale said she wouldn't want anyone to have a false sense of security.
Meningococcal disease, which affects mainly infants and teenagers aged 15 to 19, is caused by bacteria spread through spit.
Thirty-eight cases were reported in the first seven months of the year according to Environmental Science and Research.
People infected with the bacteria can deteriorate rapidly and often exhibit flu-like symptoms.
* Babies: Refusal of feeds, floppiness, vomiting
* Children and adults: fever, confusion, stiff neck and the appearance of a rash
* Seek help as soon as you think something is wrong
Ministry of Health Helpline: 0800 611 116