Notified cases of pertussis, or whooping cough, are now at epidemic levels in New Zealand.
The Ministry of Health's Dr Alison Roberts says "Numbers have been on the rise since June this year, but they really spiked up in August. We have been expecting an epidemic around now. New Zealand has a whooping cough epidemic every four to five years, and the last one started in 1999."
"It is so important that children are immunised against this disease, and we are asking Medical Officers of Health to let local GPs know and encourage parents and guardians to get their children immunised."
There were more than 350 cases of whooping cough notified in August, and 70 percent of cases were from the South Island. The age band with the highest notification rate is the 'less than one year' group.
Another 132 cases were notified in the week ending 10 September. The highest ever number of cases notified in a week in New Zealand was 148 during the last epidemic.
The last epidemic started in 1999, peaked near the end of 2000, and tailed off during 2001. In February 2002, an extra booster shot was introduced to the immunisation programme, to be given at four years of age. "This booster was designed to protect children during early school years and decrease transmission of the infection to younger children. Despite the introduction of this fifth dose into the childhood immunisation schedule, we are now into another epidemic period for pertussis," Dr Roberts said.
The latest hospitalisation data is for July, but highlights the impact is not just in the South Island. While only 8% of July notifications were from the Auckland region (Waitemata, Auckland and Counties Manukau DHBs), 53% of July's hospital admissions were from the Auckland region.