The Northern Territory is expanding its meningococcal immunisation campaign in an effort to stop its unprecedented spread in central Australia.
There have been 29 cases of the W strain of the deadly disease so far this year, with the last confirmed case on October 17.
All sufferers have been Aboriginal with the majority aged 10 or younger.
The meningococcal quadrivalent (ACWY) vaccination program has already achieved high coverage rates in "high risk" central Australian and western Katherine regions.
From Wednesday it will be rolled out to all youngsters aged one to 19 in Alice Springs, Tennant Creek and Katherine.
The vaccine will also be added to the NT Childhood Vaccination Schedule from December for all infants at 12 months of age, replacing the current meningococcal C vaccine.
NT Centre of Disease Control Director Dr Vicki Krause stressed that existing efforts targeting children remote Central Australia and Katherine regions and urban Aboriginal children in Alice Springs, Katherine and Tennant Creek would continue.
"These efforts have limited the outbreak but we need to maintain our vigilance and continue our response and look to the next step," she said.
"It is time now to vaccinate those in the lower risk group."
Dr Krause said meningococcal W is extremely hard to catch and noted bacteria continues to be carried by healthy people.
"In fact we know that the meningococcal bacteria are estimated to live in the nose and throat of about 10 per cent of the population at any one time," she said.
The free vaccine will be available for all Territorians aged one to 19 in Alice Springs, Barkly and Katherine regions.
School-based programs will commence mid-November in Katherine, Tennant Creek and Alice Springs for students in year 7 to year 12.
Earlier this month an infant from Darwin died from an unrelated B strain of the illness.
