A killer disease has claimed another life - an 18-year-old Northland man who became critically sick in just 24 hours.

Ben Brown died on Saturday, three days after being admitted to the intensive care unit at Whangarei Hospital suffering from meningococcal disease.

He is the latest in a string of casualties from the deadly infection, which has sparked an increase in precautionary measures by the district's health authority.

Mr Brown was admitted to hospital on Wednesday night in a serious condition.

District medical officer of health Dr Clair Mills said at the time that his condition had deteriorated in a 24-hour period.

He had been admitted with a headache, fever and drowsiness and placed in intensive care, and his friends and family were immediately contacted by health officials for preventive treatment.

The health board has activated its incident management team in case of further spread.

The former Kamo High School student died on Saturday afternoon - and was remembered by friends online, who arranged to get together yesterday at a skate park.

The district has had four cases of the disease this month and six this year, in line with the six to 10 cases in a typical year, mostly in winter.

A 1-year-old boy, Jacob Whyte, died earlier this month after being transferred from Whangarei Hospital to Starship children's hospital in Auckland, and his grandmother, Josie Howe, also died from the disease at Middlemore Hospital.

Ms Howe is said to have contracted the disease soon after visiting Jacob in hospital, but the health board is yet to confirm links between any of the cases.

Meningococcal disease can be carried by some people without causing harm, only to be transferred to others and cause a rapid deterioration in health.

Dr Mills said the disease could not be transferred through the air, and the best advice to avoid contagion was "don't share spit". Symptoms to watch out for were feeling sleepy, sloppy and having a headache or fever.

* Symptoms: headaches, fevers, drowsiness and rashes.

* Can cause: blood poisoning or brain infections.

* Transmission: commonly through saliva.

* Recent deaths: Jacob Whyte, 1, Northland; Josie Howe, Auckland; Ben Brown, 18, Northland; Bill Perry, 49, Christchurch; a young girl from Manawatu.