1. Phase 1 Phase 2 Phase 3 Phase 4 Phase 5 Phase 6 Cutaneous Inhalation
(Most common)
Inhalation
Intestinal
Phase 1
A virus in animals that has caused no known infections in humans
Phase 2
An animal flu virus has caused infection in humans
Phase 3
Sporadic cases or small clusters of disease that occur in humans; human-to-human transmission has been insufficient, if any, to cause community-level outbreaks
Phase 4
The risk of pandemic is greatly increased but not certain
Phase 5
Spread of disease between humans is occurring more than one country of one WHO region
Phase 6
Community-level outbreaks are in at least one additional country in a different WHO region from phase 5; a global pandemic is underway

2. PHASES OF A PANDEMIC Outbreak Epidemic Pandemic Bioterrorism Phase 1
Sudden rise in the occurrence of a disease. Sometimes a single case of a contagious
disease is considered
an outbreak.
More occurrences of a disease than normal (according to
the WHO)
Pandemic
Bioterrorism
Disease that spreads through human populations worldwide; not confined to a certain locale (according to WHO); refers
to spread, not severity
A situation in which a biological agent is intentionally released
to cause illness
Phase 1
A virus in animals that has caused no known infections in humans
Phase 2
An animal flu virus has caused infection in humans
Phase 3
Sporadic cases or small clusters of disease that occur in humans; human-to-human transmission, if any, has been insufficient to cause community-level outbreaks
PHASES OF A PANDEMIC
Phase 4
The risk of pandemic is greatly increased but not certain
Phase 5
Spread of disease between humans is occurring in more than one country of one WHO region
Phase 6
Community-level outbreaks are in at least one additional country in a different WHO region from phase 5; a global pandemic is underway

3. Cutaneous
(Most common)
Inhalation
Intestinal