Several cases of whooping cough have been confirmed in Otago.
Medical officer of health Dr Derek Bell said there were at least four cases of whooping cough in Hawea and one suspected case in Wanaka.
A ''couple'' of cases had also been confirmed in a ''small rural town near Dunedin'', which he declined to name at this stage.
''There are pockets of infection around, but we're not aware of any widespread epidemic like we've seen in the past,'' he said.
''But notification [of the illness] only represents the tip of the iceberg of what's going on ... there's likely to be a whole lot more out there that we don't know about.''
The last major outbreaks were in 2005 and 2000.
Children under the age of 12 months were most at risk because they could not be fully immunised.
Dr Bell said stopping the spread required a ''collective spirit'' in the community.
He urged people who could be vaccinated to do so, to protect those who could not.
Caregivers of children with running noses or coughs should keep them home from school and visit their doctor.
Unvaccinated children could be excluded from school until the outbreak was over, Dr Bell said.
- Jessica Maddock
