Young children and pregnant women are at higher risk of developing serious complications from influenza.
Plunket is encouraging people to take advantage of the government's free flu vaccinations to protect themselves against the potentially deadly virus.
"New Zealanders tend to underestimate what a serious disease influenza is," clinical advisory manager Karen Magrath says.
"It kills around 400 New Zealanders, directly or indirectly, each year - so it's not something we should take lightly."
Last year more than a thousand people were hospitalised after contracting the flu.
The vaccination is free to those at greatest risk of serious complications, including people over the age of 65, pregnant women and people with ongoing conditions such as asthma, diabetes or heart problems.
Ms Magrath says changes to pregnant women's lung function and immunity, as well as increased heart output and oxygen consumption place them at particularly high risk.
"We strongly advise expectant mums to get the free vaccination. Babies under 6 months old are too young to be immunised so if their mums are vaccinated they can pass protection on to their baby."
The vaccine is available until the end of July from GPs or nurses. People who are not eligible for the free vaccine can purchase it from their GP.
Go to fightflu.co.nz or call 0800 466 863.
- Auckland City Harbour News
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