"I continue to encourage our staff and the Whanganui community to have their flu vaccination," Pennefather said.
"The flu virus doesn't suddenly disappear when spring, or even summer, arrives.
"As is the case most years, those getting the flu can become very unwell. Our DHB encourages Whanganui District residents to do all they can to avoid it."
Pennefather said flu vaccinations for all New Zealanders were available up to New Year's Eve this year.
Flu vaccines are free for pregnant women, anyone under 65 with a respiratory disease or heart disease and anyone aged over 65.
Staff at practices away from the hospital had an 80 percent vaccination rate, while workers at the Whanganui Regional Health Network achieved 91 per cent coverage.