"The only effective way to manage this outbreak is with a vaccine programme," Chamberlain said.
Staffing clinics at dozens of Northland locations will also mean deploying school nurses and other health staff for the three-week, seven days a week programme to vaccinate 20,000 young children and teenagers.
With only 20,000 vaccine doses available, two age groups are targeted — the high risk nine months to under 5 year olds and 13 to 19-year-olds, exchanging higher bacteria rates than other age groups.
Immunising the groups would protect where it was most needed and have the greatest immediate impact on lessening the disease's spread, NDHB paediatrician Ailsa Tuck said.
NDHB is trying to procure another round of doses so the middle age group can be vaccinated early next year.
"We know there's going to be significant anxiety among parents of that group," Tuck said.
Be extra vigilant about children's sickness and seek medical attention early, she said.
MenW does not present with typical meningococcal symptoms but the patient becomes rapidly extremely ill.
Four of the Northland cases occurred in September and no link has been found between any of the seven local cases. Up to 20 per cent of the population can carry meningococcal bacterium in their throats or nasal passages without becoming ill, but can spread it.
Chamberlain defended the DHB against claims it did not act quickly enough. He said the initial two adult cases in May did not signify an outbreak in the community.
"The assertion we should have done something sooner is unfair."
The board's microbiologist David Hammer had warned staff at the time of those two cases, and told media yesterday his "intuition" was that cases would rise.
However, the disease's presence in the community did not become a public safety issue until reaching the MoH criteria of 10 cases per 100,000 people.
"We have to wait for outbreak status. But, absolutely, we want to immunise and, absolutely, we wish we could have started earlier," Chamberlain said. He said he was a doctor in "the dark days" of a serious nationwide meningococcal outbreak in the 1990s which no-one would want to see again.
The DHB will pay for vaccines and extra staff requirements, with the campaign likely to cost between $1-2 million. The MoH will reimburse most of the costs. Parents whose children are between five and 13, or others in the community who want immunisation can pay privately for a vaccine from their GP.
The free vaccine clinics will be held in schools and community centres, with times and places advertised in the media and online forums from tonight.