There was no link between the cases, which were both Māori and Pākehā from a range of ages and areas of Northland.
"We are targeting those two population groups because research shows that vaccinating them will have the greatest impact on reducing meningococcal disease spreading in the entire community,'' Northland District Health Board chief executive Nick Chamberlain said.
The DHB now faces a ''huge logistical feat'' to get the target population vaccinated before the Christmas/New year holiday period.
The DHB and Ministry of Health (MoH) have had to dig deep for available supplies of the MenW vaccine globally to buy 20,000 doses.
Chamberlain said the DHB hoped to eventually procure enough of the vaccine for the rest of Northland's under-20 population.
Clark said the relatively new to New Zealand meningococcal W strain had a recognised high mortality rate.
"Pharmac and the Ministry of Health will continue to investigate the availability of further doses of the vaccine as a contingency, in case further rollout of the programme is recommended," he said.
The DHB came under fire earlier this month for not telling the public about the Northland cases for six months after the illness showed up. It only began warning the public to be alert for symptoms after the MoH announced it was in discussion with the Northland board following a disproportionately high number of local cases.
Dr Chamberlain, microbiologist David Hammer and paediatrician Roger Tuck will hold a media conference today about the Northland community vaccination programme.