Avian Bird Flu, Pandemic Alert Phase, Hawaii Avian Influenza Website

Avian Flu: A Pandemic Threat

Experts at the World Health Organization (WHO) and elsewhere believe that the world is now closer to another influenza pandemic than at any time since 1968, when the last of the twentieth century's three pandemics occurred. The WHO uses a series of six "phases of pandemic alert" as a system for informing the world of the severity of the threat, and for the need to launch increasingly intense preparedness activities. The designation of phases, including decisions on when to move from one phase to another, is made by the Director-General of WHO.

Each alert phase coincides with a series of recommended activities that are collectively undertaken by WHO, the international community, governments, and industry. Changes from one phase to another are triggered by several factors, including the epidemiological behavior of the disease, and the characteristics of circulating viruses.

Due to the onset of influenza A (H1N1) virus, commonly known as Swine Flu, the world is presently in Phase 6 of the Pandemic Alert Period according to WHO.

Pandemic Periods and Phases
Current Pandemic Threat at Phase 6
Interpandemic Period
Phase 1 No new influenza virus subtypes have been detected in humans. An influenza virus subtype that has caused human infection may be present in animals. If present in animals, the risk of human infection or disease is considered to be low.
Phase 2 No new influenza virus subtypes have been detected in humans. However, a circulating animal influenza virus subtype poses a substantial risk of human disease.
Pandemic Alert Period
Phase 3 Human infection(s) with a new subtype, but no human-to-human spread, or at most rare instances of spread due to close contact.
Phase 4 Small cluster(s) of limited human-to-human transmission. But the spread is highly localized, suggesting that the virus is not well adapted to humans.
Phase 5 Larger cluster(s) of limited, localized human-to-human transmission, suggesting that the virus is becoming increasingly better adapted to humans, but may not yet be fully transmissible. There is a substantial pandemic risk (Phase 6).
Pandemic Period
Phase 6 Pandemic: increased and sustained human-to-human transmission in the general population.
Sources taken from WHO's global influenza preparedness plan.

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