Whether it’s COVID-19, swine flu, or smallpox, we hear the wordpandemicused in a variety of ways. What does pandemic really mean, and when is the term really warranted?A pandemic refers to an illness that has spread over several countries or continents, usually affecting a large number of people.It takes into account where it is located and how it is spreading. Most recently, theWorld Health Organization (WHO)declared COVID-19 a pandemic.Verywell / Tim LiedtkePhases of a PandemicThe Centers Disease for Disease Control and Prevention (CDC) currently hasPandemic Intervals Framework (PIF)in place for tracking the phases of an influenza pandemic. That framework is being applied to COVID-19.Phase 1: Investigation IntervalA new type of virus is identified and investigated—in animals or humans anywhere in the world—that is thought to have implications for human health.Phase 2: Recognition IntervalIncreased cases, or clusters of cases, are identified, along with an increased potential for person-to-person transmission.Phase 3: Initiation IntervalCases of the virus are confirmed with both efficient and sustained person-to-person transmission.Phase 4: Acceleration IntervalThe new virus infects susceptible people. Public health officials may take measures such as closing schools, encouraging social distancing, and offering antivirals or vaccines—if available.Phase 5: Deceleration IntervalThere is a consistently decreasing rate of cases in the United States.Phase 6: Preparation IntervalEven after the pandemic has subsided, public health officials continue to monitor the virus and brace for another wave of illness.The information in this article is current as of the date listed, which means newer information may be available when you read this. For the most recent updates on COVID-19, visit ourcoronavirus news page.
Whether it’s COVID-19, swine flu, or smallpox, we hear the wordpandemicused in a variety of ways. What does pandemic really mean, and when is the term really warranted?
A pandemic refers to an illness that has spread over several countries or continents, usually affecting a large number of people.It takes into account where it is located and how it is spreading. Most recently, theWorld Health Organization (WHO)declared COVID-19 a pandemic.
Verywell / Tim Liedtke
Phases of a Pandemic
The Centers Disease for Disease Control and Prevention (CDC) currently hasPandemic Intervals Framework (PIF)in place for tracking the phases of an influenza pandemic. That framework is being applied to COVID-19.
Phase 1: Investigation Interval
A new type of virus is identified and investigated—in animals or humans anywhere in the world—that is thought to have implications for human health.
Phase 2: Recognition Interval
Increased cases, or clusters of cases, are identified, along with an increased potential for person-to-person transmission.
Phase 3: Initiation Interval
Cases of the virus are confirmed with both efficient and sustained person-to-person transmission.
Phase 4: Acceleration Interval
The new virus infects susceptible people. Public health officials may take measures such as closing schools, encouraging social distancing, and offering antivirals or vaccines—if available.
Phase 5: Deceleration Interval
There is a consistently decreasing rate of cases in the United States.
Phase 6: Preparation Interval
Even after the pandemic has subsided, public health officials continue to monitor the virus and brace for another wave of illness.
The information in this article is current as of the date listed, which means newer information may be available when you read this. For the most recent updates on COVID-19, visit ourcoronavirus news page.
1 SourceVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Centers for Disease Control and Prevention.Epidemic disease occurrence.
1 Source
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Centers for Disease Control and Prevention.Epidemic disease occurrence.
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Centers for Disease Control and Prevention.Epidemic disease occurrence.
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