Return to phase 0. Post pandemic period Return to interpandemic period. Return to interpandemic period. The distinction would be based on various factors and their relative importance according to current scientific knowledge. Various factors and the irrelative importance according to current scientific knowledge may be considered. Rare instances of spread from a case to close household or unprotected healthcare contacts without evidence of sustained human-to-human transmission.
One or more small independent clusters1 of human cases such as family members who may have acquired infection from a common source or the environment, but for whom human-to-human transmission cannot be excluded.
Persons whose source of exposure cannot be determined, but are not associated with clusters 1 or outbreaks of human cases. Small cluster s with limited human-to-human transmission but spread is highly localized, suggesting that the virus is not well adapted to humans. Virus has increased human-to-human transmissibility but is not well adapted to humans and remains highly localized, so that its spread may possibly be delayed or contained.
One or more clusters 1 involving a small number of human cases, e. Larger cluster s but human-to-human spread still localized, suggesting that the virus is becoming increasingly better adapted to humans, but may not yet be fully transmissible substantial pandemic risk. Virus is more adapted to humans, and therefore more easily transmissible among humans. It spreads in larger clusters, but spread is localized.
This is likely to be the last chance for massive coordinated global intervention, targeted to one or more foci, to delay or contain spread. In view of possible delays in documenting spread of infection during pandemic phase 4, it is anticipated that there would be a low threshold for progressing to phase 5.
Ongoing cluster-related transmission, but total number of cases is not rapidly increasing, e. In a community known to have a cluster, appearance of a small number of cases whose source of exposure is not readily apparent e.
Appearance of clusters caused by same or closely related virus strains in one or more geographical areas without rapidly increasing numbers of cases. These unusual observations may include: The distinction between phase 3, phase 4 and phase 5 is based on an assessment of the risk of a pandemic. Various factors and their relative importance according to current scientific knowledge may be considered.
Pandemic period Phase 6. Increased and sustained transmission in the general population. Major change in global surveillance and response strategy, since pandemic risk is imminent for all countries. The national response is determined primarily by the disease impact within the country. Post pandemic period A return to the interpandemic period the expected levels of disease with a seasonal strain follows, with continued need to maintain surveillance and regularly update planning.
An intensive phase of recovery and evaluation maybe required. Simultaneous occurrence of situations posing different levels of pandemic risk In the event of simultaneous situations posing different levels of risk, e. Criteria for downscaling of phases All phases except phase 1 are anticipated to be temporary. With every announcement of a new phase, WHO will set a time period at which the designation will be reviewed.
In consideration of downscaling, the following criteria will be used: Lack of on going disease activity meeting the criteria for the current phase. Adequate, if necessary onsite, risk assessment by WHO in partnership with affected countries, and for issues relating to infection in animals, in partnership with other organizations such as FAO and OIE.
A risk assessment considering the factors that led to designation of the phase, 1, 2 as well as other potential factors. For example, if the respiratory illness season is in progress in the region, downscaling might sometimes be delayed because of the increased risk that new strains might reassort with seasonal strains, and that surveillance to detect new strains co circulating with seasonal strains might be more difficult.
Procedure for decision making Designation of phases, including decisions on up scaling and downscaling, will be made by the Director General of WHO. The designation will be made in harmony with existing regulations governing human disease reporting and control e.
The national subdivisions of phases will be designated by national authorities. The distinction between phase 1 and phase 2 is based on the risk of human infection or disease resulting from circulating strains in animals.
The distinction is based on various factors and their relative importance according to current scientific knowledge. Overarching goals, objectives and actions for each phase Table 2 provides an overview of objectives and actions that WHO will take and recommend to national authorities to address the over arching priority goals.
Objectives and actions are divided into five categories: Planning and coordination Prevention and containment non pharmaceutical public health interventions, vaccines, and antivirals Health system response Communications The extent of implementation will depend on available resources.
The proposed measures are based upon current knowledge of outbreaks of seasonal influenza and past pandemics. Recommendations may be adjusted based on new evidence and experience.
Actions are intended to continue after up scaling to higher phases unless they are superseded by actions in the higher phase. If an up scaling designation skips a phase, actions in the skipped phase should also be implemented, unless they are superseded by actions in the higher phase. Table 2 Overarching goals, objectives and actions for WHO and national authorities, by phase Interpandemic Period Interpandemic period, phase 1 - Overarching goal Strengthen influenza pandemic preparedness at the global, regional, national and sub national levels.
Interpandemic period, phase 1 - Planning and coordination Phase 1 National Objectives To promote the development of harmonized global, regional and national influenza pandemic preparedness plans. To promote the development of global and national capacity to detect and respond to early reports of new strains.
To develop strategies and procedures to coordinate the rapid mobilization and deployment of global resources to foci of infection during a pandemic alert period. To improve international response to pandemic influenza and other health emergencies by developing mechanisms for rapid decision making and action, establishing intersectoral collaboration, and promoting corresponding measures at the national level. To develop and maintain national influenza pandemic contingency plans which are in harmony with international plans.
To promote national and global capacity to respond to early reports of new influenza virus strains. To develop effective mechanisms for mobilization and rapid deployment of resources to areas of need. To develop effective mechanisms for decision making and subsequent actions regarding national and international responses to influenza related health emergencies, by strengthening intersectoral and intergovernmental cooperative arrangements that will identify and minimize the risk of human infection with a new influenza virus.
Encourage and assist comprehensive national pandemic influenza planning. Develop tools to estimate influenza seasonal and pandemic disease burden, and the public health value and cost effectiveness of interventions, including seasonal vaccination.
Facilitate implementation of pandemic plans through preparedness activities, including exercises. Member States, other international organizations, nongovernmental organizations and the private sector, to facilitate implementation of the global plan. Promote agreements to develop, manage and deploy a global stockpile e. Harmonize pandemic planning with other international legal and policy instruments, e.
Develop surge capacity contingency plans for the internal management of WHO resources and staff during a pandemic. Establish international guidance to address food safety and other public health issues related to infected animals.
Establish a national pandemic planning committee. Advocate the importance of pandemic planning to relevant decision makers. Develop and periodically update national plans in close collaboration with relevant partners, including those outside the health sector, and with reference to current WHO guidance. Ensure implementation of plans and preparedness activities at all levels of public authorities.
Exercise pandemic plans and use the results to improve and refine plans and preparedness. Identify, brief regularly and train key personnel to be mobilized in case of emergence of a new influenza virus strain.
Consider the development of a domestic stockpile antiviral's, personal protective equipment, vaccines, laboratory diagnostics, other technical support for rapid deployment when needed. Consider providing resources and technical assistance during pandemic alert periods to resource poor countries with foci of influenza activity. Ensure procedures for rapid sharing of specimens or isolates for virus characterization and development of diagnostics and vaccine.
Develop surge capacity contingency plans for the internal management of domestic resources and essential workers during a pandemic. Establish national guidance to address food safety, safe agricultural practices and other public health issues related to infected animals.
Interpandemic period, phase 1 - Situation monitoring and assessment WHO Objectives National Objectives To coordinate global surveillance networks that monitor trends of human infection with seasonal strains, and provide early warning of new strains in humans and animals in collaboration with other partners and organizations, e. To promote the development of global and national capacity to assess risks to humans from animals and other possible sources of human infection with new strains.
To promote the development of national plans for ongoing assessment of impact and resource needs during the pandemic period. To have available up to date information on trends in human infection with seasonal strains of influenza. To be able to detect animal and human infections with new influenza virus strains, identify potential animal sources of human infection and assess the risk of transmission to humans.
To develop plans for ongoing assessment of impact and resource needs during the pandemic period. WHO Actions National Actions Strengthen the global influenza surveillance network and other laboratories to increase national capacity for influenza surveillance. Work with national authorities and other partners e.
FAO and OIE to coordinate a research and monitoring programme for the human-animal interface, and use data collected to assess the risk of human infection with animal influenza viruses. Facilitate sharing of influenza virus strains for reagents development and sub typing of new viruses. Encourage relevant national authorities, such as animal and public health authorities, to establish intersectoral and inter institutional collaboration in influenza surveillance.
Develop or review interpandemic and pandemic guidelines and tools for detection, investigation, rapid risk assessment, reporting and on going evaluation e. Develop guidelines and tools to assist countries in ongoing monitoring of information, for assessment of impact and resource needs during the pandemic phase. Develop robust national generic surveillance systems for the detection, characterization and assessment of clusters of influenza like illness or respiratory deaths, with provision for surge capacity and intersectoral and inter institutional collaboration.
Report routine and unusual surveillance findings to relevant national and international authorities. Assess burden of seasonal influenza to help estimate additional needs during a pandemic. Develop contingency plan for ongoing monitoring of information, for assessment of impact and resource needs during the pandemic phase e.
WHO Objectives Interpandemic period, phase 1 - Prevention and containment To ensure the availability of up to date , evidence based recommendations on potential interventions.
To promote the increased use of seasonal influenza vaccine, consistent with WHO recommendations. To coordinate efforts to resolve impediments to the development, production and access to pandemic vaccines. To assess the needs and develop strategies and guidelines for development, deployment and use of global stockpiles. To agree in advance a range of containment strategies based on non pharmaceutical public health actions. To develop a strategy regarding stockpiling of antivirals and criteria for deployment.