Health officials say the public has become lax in protecting themselves against influenza this season.
They're concerned about a strain of the virus, H3N2, which can have severe symptoms especially on the elderly.
Virus expert Dr Lance Jennings says after the influenza pandemic of 2009, they're unsure what the next dominant strain of the virus will be.
But he stresses it's important for people to take measures to protect themselves.
He says people have become a bit complacent and the number of people receiving vaccinations has dropped.
Photo: NZ Herald