Guidance for pandemic preparedness
WHO global guidance on "Pandemic influenza risk management" aims to inform and harmonize national and international pandemic preparedness and response. It describes the main components of pandemic planning at a national level as well as the main roles and responsibilities of WHO in a pandemic.
Implementation of lessons learnt
The guide introduces new approaches to pandemic preparedness based on the experience from the 2009 pandemic.
a) It emphasizes the importance of all-hazard preparedness as a framework within which countries should prepare for an influenza pandemic. This is in line with the International Health Regulations (2005), which stipulate that countries must strengthen their ability to manage threats from all hazards, for example by enhancing multisectoral collaboration and whole-of-society preparedness.
b) As the severity of an influenza pandemic cannot be predicted beforehand, pandemic plans should include multiple scenarios, while the response will be based on actual severity determined by national risk assessment. Response measures should thus be scalable according to the actual severity and impact of the pandemic, and may be implemented at different times within a country depending on local pandemic spread.
Pandemic phases
c) In line with such a flexible approach to pandemic planning and response at the national level, WHO guidance presents 4 global pandemic phases (revised in 2009), which describe how an influenza pandemic may emerge and spread and are not linked to actions to be taken at the national or subnational level:
- interpandemic phase (the period between influenza pandemics);
- alert phase (when influenza caused by a new subtype has been identified in humans);
- pandemic phase (the period of global spread of human influenza caused by a new subtype); and
- transition phase (when the global risk reduces and reduction in response activities may be appropriate).
The phase is determined by ongoing global risk assessment, based on virological, epidemiological and clinical data for new influenza subtypes. The world is currently in an alert phase because of the avian influenza A(H5N1).
