In New Zealand we have seen peaks in whooping cough cases in May, June, July and another steady increase since September.

A total of 263 cases have been reported in the last four weeks (between October 19 and November 15) – the highest number of cases in a four-week period so far this year.

These numbers may also not be representative of the current situation as health experts warn that most people will not be tested.

“Most cases may not be very sick so when you look at what you see and you look at the cases that are reported, it’s the tip of the iceberg,” Petousis-Harris said.

Although epidemics can still occur with high vaccination rates, the number of children who become very ill will be much lower if that rate is increased.

“Even in countries with very high levels of immunization, epidemics still occur every few years, but the number of infants who become very ill is much lower when mothers are vaccinated during pregnancy and when pēpi are vaccinated on time,” Jones said.

The pertussis vaccine isn’t very good at preventing transmission, Petousis-Harris said, but it is “pretty good at preventing someone from getting sick.”

Whooping cough is almost as contagious as measles and people can carry it without showing signs of illness, meaning it will spread silently within communities, with many not even knowing they are infecting others.

“So that’s another real challenge for us so there could be quite a lot circulating in the community. Just assume for now that it’s probably everywhere,” she said.

About 50% of children who get whooping cough before the age of one year need to be hospitalized. One or two in 100 children will die from the infection.

“Our biggest concern with this epidemic is the risk of serious disease among infants who are either too young to be vaccinated or whose immunizations are delayed,” Jones said.

“Our main goal is to protect pēpi through timely vaccination and immunization during pregnancy.”

And as in previous epidemics, he said the most affected babies will be Maori and Pacific babies.

“Sadly, three children died from whooping cough last year, and we want to prevent that from happening again,” Petousis-Harris said.

“The best protection for babies is for their mother to be vaccinated during pregnancy. The prenatal vaccination against whooping cough is safe and free.

“This is most effective when given from 16 weeks of pregnancy – and should be done during every pregnancy to provide the best protection for each baby.”

If you are pregnant and can get the whooping cough vaccine, please get vaccinated. You can save your child’s life – or at least you will be doing your part to ensure that fewer children get seriously ill in Aotearoa.