As people gather for holiday celebrations, the Ministry of Health is encouraging them to be extra vigilant in protecting babies from whooping cough.
There have been more than 6700 cases of whooping cough since August last year.
Chief adviser for child and youth health Pat Tuohy says one person with whooping cough can pass it on to about 17 others.
He says anyone with a cough should be especially careful about coming into contact with babies.
From 1 January, women between 28 and 38 weeks of pregnancy can be vaccinated for free against the disease.
The immunisation programme for babies begins at six weeks of age.