WHO Phases

The current WHO phase of pandemic alert for avian influenza A(H5N1) is: ALERT

JUNE 10, 2013 WHO released new interim guidelines, with redesigned pandemic phases.

  • Interpandemic phase: This is the period between influenza pandemics.
  • Alert phase: This is the phase when influenza caused by a new subtype has been identified in humans.
  • Pandemic phase: This is the period of global spread of human influenza caused by a new subtype.
  • Transition phase: As the assessed global risk reduces, de-escalation of global actions may occur, and reduction in response activities or movement towards recovery actions by countries may be appropriate, according to their own risk assessments.

WHO Pandemic Phases Continuum

Pandemic Influenza Risk Management, WHO Interim Guidance Figure 1. The continuum of pandemic phases, World Health Organization, http://www.who.int/influenza/preparedness/pandemic/influenza_risk_management/en/index.html, accessed August 2013