HUMAN INFLUENZA PANDEMIC PLANNING
What is Pandemic Influenza?
Pandemic influenza occurs when a new influenza virus subtype to which there is little or no immunity emerges, is easily spread between humans and is capable of causing severe disease in humans. In the absence of immunity and before a vaccine becomes available, the new subtype can rapidly spread across the globe, causing worldwide epidemics or 'pandemics' with high numbers of cases and deaths.
Three influenza pandemics occurred during the 20th century, the "Spanish" (1918), "Asian" (1957) and "Hong Kong" (1968) pandemics. The Spanish pandemic resulted in an estimated 40 to 50 million or more deaths worldwide, while the Asian and Hong Kong pandemics resulted in an estimated 2 million and 1 million deaths respectively. Influenza experts agree that another pandemic is inevitable, although the timing and health impact are unpredictable.
The avian influenza virus H5N1 causes a disease of birds commonly known as "bird flu" that only occasionally affects humans and is not easily spread between people. Health authorities are concerned that if the virus evolves to become more easily transmitted between people it could cause an influenza pandemic, however, a pandemic could also be caused by another influenza strain. The World Health Organisation is coordinating the global response to human cases of H5N1 avian influenza and monitoring the corresponding threat of an influenza pandemic.
For more information, see Preparing for a human influenza pandemic Fact Sheet 1 - Pandemic influenza FAQs or visit these websites:
Commonwealth Department of Health and Ageing
World Health Organisation