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Health Minister Tony Ryall has bared his arm for his annual flu shot, at a Wellington surgery, as a leading virologist warned that the vaccinations may literally be a matter of life or death for some New Zealanders.
"A vaccine is our best protection against influenza," says Christchurch virologist Lance Jennings.
Medical authorities in the northern hemisphere have warned that a flu virus known as the "Brisbane strain" may be the most deadly form of the virus seen in Europe in the past 20 years.
It killed six children in Australia last winter.
New Zealand's most serious flu season in recent years saw three children die from the disease during the influenza B epidemic of 2005.
But over 13 years from 1980 to 1992, a total of 5650 New Zealanders died from influenza, at a rate of more than 400 a year.
This year's influenza vaccine contains a Brisbane H3N2-like strain, an H1N1-like strain and a B strain.
"They are the strains most likely to affect us, because they are the dominant strains in the northern hemisphere," Jennings says.
But health authorities can never be certain of this because the strains might start "shifting" or mutating, or a new strain could emerge before winter.
In healthy people, the vaccines can protect about 90% of the people immunised before the seasonal influenza spreads, fewer if different strains become important. The number of doses of vaccine available this winter will cover about 18% of the population.
The people at greatest risk, elderly people with waning immune systems, children over six months and adults with chronic medical conditions were eligible for free vaccinations.
Jennings says all strains are potentially dangerous to children.
The Brisbane H3N2 strain has placed huge demands on health services in Europe, while in the United States an H1N1-like strain has been dominant.
The United States experience had been complicated by the fact that virtually all cases of this strain were proving resistant to the anti-viral medication Tamiflu, which is more commonly used for treatment in Japan and the US than in New Zealand.
Four American patients infected with the resistant strain have died, including two children, but Jennings said the US had not crossed the trigger levels for declaration of an epidemic.
New Zealand had no H1N1 virus last flu season, and only started to see the emergence of the Brisbane H3N2 strain: "If either of these viruses start circulating in NZ this year, particularly the H3 virus, we could have a severe year," he says.
The H3N2 virus usually causes more severe infections and has more serious outcomes in adult patients.
New Zealand tends to use little Tamiflu for treatment, once a person falls sick, but if the H1N1 virus resistant to the anti-viral drug does spread in NZ, then Tamiflu might only be effective against H3 and B flu viruses, which have been the most widespread in this country recently.
Jennings says people can, in addition to seeking vaccination, also take a low-tech approach by focusing on personal hygiene.
Some schools are running a "sneeze-safe" programme, advocating a cover-up of coughs and sneezes as a form of respiratory hygiene. They also encourage use of tissues, preferably tissues treated to kill viruses, and a focus on handwashing.
Such behaviours can build resilience for the next global flu pandemic, along with practices such as keeping a metre away from other people and keeping enough food in the house to survive without being able to get to shops, he says.
A variant of the H1N1 virus caused the 1918 influenza epidemic that killed an estimated 50 million people worldwide.
