Whanganui Regional Health Network (WRHN) is warning families the holiday period will likely increase the spread whooping cough cases.
There have been 25 cases in Whanganui in the year to November and 539 in the central region.
In November, Whanganui was declared a whooping cough hotspot after sitting at the third-highest infection rate of the health districts, with a rate of infection at 11.4 cases per 100,000 people.
WHRN chief executive Judith Macdonald said travellers returning from overseas and large family gatherings over Christmas would create a heightened risk.
“We are now back to almost pre-Covid rates of travelling globally — that’s why we’re at risk.”