The flu vaccine will arrive a few weeks late this year because it had to be changed to include strains missed in the northern hemisphere.
The Ministry of Health announced yesterday it would arrive in general practices in early April.
The ministry was working closely with Pharmac, vaccine suppliers and the health sector to ensure the flu vaccine campaign progressed smoothly after the ''global delay'', ministry chief medical officer Dr Don Mackie said.
''This year's southern hemisphere vaccines contain two new strains, to give better protection against the influenza strains that have been circulating around the world through the northern hemisphere winter.
''We hope the improved southern hemisphere vaccines will avoid the difficulties the United States, United Kingdom and Europe have had with a poor match for the H3N2 component of the vaccine.''
Dr Mackie said the vaccine would arrive well in advance of the flu season, but meant GPs would be busier than usual in April and May.
Mosgiel Health Centre manager Kathryn Tohill did not expect the delay to cause much disruption. Last year, the vaccine arrived in late February.
''We've normally kicked off our flu clinics in March, so there will be a delay, obviously.''
Last year, the Mosgiel centre administered 3000 vaccines, of which 2250 were for people aged over 65, for whom the vaccine is funded.
Green Island Medical Centre nurse team leader Yvonne Munro said warmer-than-usual weather recently made it unlikely many patients were thinking about flu just yet.
A few patients liked to be vaccinated early, in March, but most preferred to wait until later, she said.
''For us, I don't think it will be a major hassle at all,'' Mrs Munro said.
Last month, The Guardian newspaper reported the vaccine was estimated to work in just 3% of cases in lab tests (conducted in England) because of the mismatch with the prevalent strains.