Dr Mills said they were still waiting for test results to determine what strains the children had contracted.
She said the cases "appear to be completely unrelated".
"Ones from Whangarei, the other is from outside Whangarei, there are no contacts between them that we are able to establish."
In the past 10 days the meningococcal disease has claimed two lives - a young Manawatu girl who died in Rotorua Hospital and Fulton Hogan chief executive Bill Perry, who died in Christchurch Hospital.
Following Mr Perry's death three people were taken to hospital with the type-C strain of the disease.
Dr Mills said Northland usually has about five to eight cases each year.
"We've had a few this year but probably about as much as you'd expect. I think it is just a coincidence that we've had two in a week."
Parents whose children show the symptoms of the disease should act fast, Dr Mills said.
"For the younger children they usually present with a high fever, they're off their food, vomiting, often quite stroppy and sleepy. We tell people not to wait for any rash or spots, because that's really quite late and it can happen very fast.
"If parents are concerned they need to seek medical attention and not put it off.
"In young adults and older children they tend to complain of a sore neck and a head ache and vomit. And often they will complain of bright lights and their eyes hurting."
Dr Mills said a recent European study suggested as much as five per cent of children and over 20 per cent of teenagers carry some strain of the bug.
"It's a bug that many of us carry all the time. And it is usually from close contact with other household members [that young children contract the disease from]. So we mostly carry it without knowing we've got it."
Dr Mills said the recent run of meningococcal disease cases were not an "outbreak".
"Usually an outbreak is a doubling of cases in a certain period," she said. "[For] an outbreak they've got to be related."
Anyone who is concerned should contact their doctor or call Healthline on 0800 611 116.
