A South Auckland mum who witnessed her baby boy turn blue and struggle for breath says she would have likely lost her son that day if he had not been vaccinated.
In March last year, Kaiden Russell, who was only 4 months old at the time, was rushed to Auckland's Middlemore Hospital after his mother suspected whooping cough.
Turns out, she was right - the nurse diagnosed it straight away and he spent three days in the hospital recovering from the disease.
"It was really, really scary and heartbreaking seeing your child suffer like that," said his mum Natalie.
She believes, and her doctors agreed, her son could have died had he not had his first dose of the pertussis vaccine at six weeks.
"He responded within 24 hours of getting medicine so we were so lucky he had that first dose; it could have been fatal otherwise."
Now, the "boisterous and confident" young boy is healthier and more lively than ever.
But looking back, Natalie says he didn't fall into the group of children more likely to get the disease.
"Our whole family had all been immunised and he'd had his first dose - so it definitely makes you more aware that this kind of thing can still happen and it is so serious people [need to] get immunised when they are supposed to."
The pertussis vaccine is part of the free immunisation schedule for children in New Zealand. Babies get doses at 6 weeks, 3 months and 5 months. Booster immunisations are given to children when they're 4 and 11 years old.
For more information, visit the Ministry of Health website.