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FLU PREPAREDNESS

Pandemic Descriptions and Social Distancing

WHO Pandemic Phase Descriptions

Phase Description
Phase 1 No animal influenza virus circulating among animals have been reported to cause infection in humans.
Phase 2 An animal influenza virus circulating in domesticated or wild animals is known to have caused infection in humans and is therefore considered a specific potential pandemic threat.
Phase 3 An animal or human-animal influenza reassortant virus has caused sporadic cases or small clusters of disease in people, but has not resulted in human-to-human transmission sufficient to sustain
Phase 4 Human to human transmission of an animal or human-animal influenza reassortant virus able to sustain community-level outbreaks has been verified.
Phase 5 The same identified virus has caused sustained community level outbreaks in two or more countries in one WHO region.
Phase 6 In addition to the criteria defined in Phase 5, the same virus has caused sustained community level outbreaks in at least one other country in another WHO region.
Post Peak Period Levels of influenza activity have returned to the levels seen for seasonal influenza in most countries with adequate surveillance.
Post Pandemic Period Levels of influenza activity have returned to the levels seen for seasonal influenza in most countries with adequate surveillance.
 

CDC
Pandemic Severity Index
Social Distancing

(Phase descriptions follow the table)

SETTING

INTERVENTIONS

Phase 1

Phases 2 & 3

Phases 4, 5 & 6

HOME

           

Voluntary isolation of ill at home (adults and children); combine with use of antiviral treatment as available and indicated

 

Recommend

 

Recommend

 

Recommend

Voluntary quarantine of household member in home with ill person (adults and children); consider combining with antiviral prophylaxis if effective, feasible, and quantities sufficient

 

Generally not recommended

 

Consider

 

Recommend

SCHOOL

           

Child Social Distancing:

   Dismissal of students from schools and school-based activities, and closure of child care programs

 

Generally not recommended

 

Consider:
<4 weeks

 

Recommend:
<12 weeks

   Reduce out-of-school social contacts and community mixing

Generally not recommended

Consider:
<4 weeks

Recommend:
<12 weeks

WORKPLACE / COMMUNITY
           

Adult Social Distancing:

   Decrease number of social contacts (e.g., encourage teleconferences, alternatives to face-to-face meetings)

Generally not recommended

Consider

Recommend

   Increase distance between persons (e.g., reduce density in public transit, workplace)

Generally not recommended

Consider

Recommend

   Modify, postpone or cancel selected public gatherings to promote social distance (e.g., postpone indoor stadium events, theatre performances

Generally not recommended

Consider

Recommend

 

   Modify work place schedules and practices (e.g., telework, staggered shifts)

Generally not recommended

Consider

Recommend