Cases of whooping cough are on the rise in Canterbury.
The disease, also known as pertussis, is potentially fatal for babies under 12-months-old.
Like many countries, New Zealand has an outbreak every three to five years.
The last big one was in 2017 and 2018 so we are due for another, health authorities say.
The latest notifiable disease data shows 22 cases were reported in Canterbury/West Coast during July, compared to just 11 the previous month.
Six of the cases were in the Ashburton district.
Te Whatu Ora immunisation taskforce chair Owen Sinclair has previously said there will be many more people in the community with the disease than there are notified cases.
He said pertussis can range from a cough to something much more serious.
"They cough and then they go blue and then you put their arms about their head and sort of waft oxygen over their face and go: ‘Please breathe, please breathe'," Sinclair said.
"And they do or they don't ... there's nothing you can do about it.
"It's awful. It's really distressing from a medical perspective."
Babies should get a vaccine from 16 weeks of every pregnancy to protect them. Then they need three doses when they are six weeks, three months and five-months-old.
Booster doses are also given at ages 4, 11, 45, and 65.
