"Unfortunately, it is adults who are often responsible for spreading the infection to children."
He said adults often put up with a cough, and didn't seek medical treatment until it was too late - unintentionally spreading the illness.
Dr Shoemack said those who had an unexplained cough for more than a few days should go to their GP and get a diagnosis confirmed, to protect others.
In some cases, an antibiotic could be used to stop people from being infectious, Dr Shoemack said.
The outbreak was a good reminder of the importance of vaccinating children, with the vaccination part of the childhood schedule and also free for pregnant women.
Dr Shoemack said the vaccine was also recommended for household members and grandparents of newborn babies.
"It's particularly young babies who are most at risk."
Those getting whooping cough in the Rotorua area were a mix of adults and children, he said.
Dr Shoemack said whooping cough outbreaks tended to happen in five-yearly cycles, and the country was in one of the peak phases at the moment.
What is whooping cough?
- A highly infectious disease
- Spread by coughing and sneezing
- Caused by bacteria which damage breathing tubes
- Particularly dangerous in infants
- Can be vaccinated against
- People are infectious from six days after exposure to three weeks after the 'whooping' cough begins
- Antibiotics can reduce the infectious period
Number of notified cases for Rotorua district residents
2014 - 15 cases
2015 - 9 cases
2016 - 32 cases
