Influenza - Most People Unlikely to Have Immunity
5 December 2006
Annual influenza immunisation stimulates the immune system as though the body had been infected naturally with the disease (even though the vaccine contains no live virus).
However, in a recent independent survey1 of New Zealanders attitudes to influenza immunisation carried out on behalf of the National Influenza Strategy Group (NISG2), a surprising 44 percent interviewed were under the false impression that it was better to build up natural immunity to the disease through a healthy diet and alternative therapies.
You can only be immune to a particular strain of the virus if youve had it before. And, as the virus strains keep changing each year, most people are unlikely to have natural immunity. Thats why annual immunisation is so important to provide protection from the strains most likely to circulate in New Zealand. The inactivated influenza vaccine provides the best protection against influenza, explains virologist and NISG spokesperson Dr Lance Jennings.
The recommended influenza vaccine composition
for New Zealand in 2007, which has recently been announced
by the Governments medicines regulatory body,
A(H1N1): an A/New Caledonia/20/99 (H1N1)-like strain (15 μg HA per dose)
A(H3N2): an A/Wisconsin/67/2005 (H3N2)-like strain (15 μg HA per dose)
B: a B/Malaysia/2506/2004-like strain (15 μg HA per dose)
This recommendation is based on the outcome of:
The meeting of the Australian Influenza Vaccine Committee, with a New Zealand representative, to consult on the influenza vaccine composition for 2007 (held in Canberra on October 4, 2006),
Information on international surveillance by the World Health Organisation (WHO),
Recent data from Australia, New Zealand and South Africa and Argentina on epidemiology and strain characterisation, and the recommendations of the WHO annual consultation on the composition of influenza vaccine for the Southern Hemisphere (held in Geneva on September 18-20, 2006).
Influenza immunisation is free for New Zealanders at high risk of complications -- people aged 65 and over, and those under 65 years of age with long-term health conditions such as heart disease, stroke, diabetes, respiratory disease and most cancers from early March to June 30, 2007. Many employers provide influenza vaccination free to employees.
The new vaccine is expected to be available in early March 2007.
A record number of New
Zealanders received influenza vaccinations this year. When
the Government-subsidised influenza vaccine campaign ended
on June 30 a total of 761,180 doses of the vaccine had been
distributed, a 6% increase on 2005.
1 TNS NZ research Assessing the impact of the 2006 Influenza Immunisation advertising campaign research conducted among eligible groups i.e. people 65 and over and people with chronic conditions.
2National Influenza Strategy Group
NISG was formed in 2000 by the Ministry of Health to increase public awareness of influenza, its seriousness and the importance of immunisation to prevent the disease.