Seasonal Flu vs Pandemic Flu
What Is a Flu Pandemic?
A pandemic is a global disease outbreak. An influenza pandemic occurs when a new influenza Type A virus emerges for which there is little or no immunity in the human population. Next, it begins to cause serious illness and spreads easily from person to person worldwide. A pandemic is determined by the spread of disease, not its ability to cause death.
Pandemic flu is different from seasonal flu.
|Seasonal Flu||Pandemic Flu|
|Outbreaks follow predictable seasonal patterns; occurs annually, usually in winter, in temperate climates.||Occurs rarely (three times in the 20th century).|
|Usually some immunity built up from previous exposure.||No previous exposure; little or no preexisting immunity.|
|Healthy adults usually not at risk for serious complications; the very young, the elderly, and those with certain underlying health conditions at increased risk for serious complications.||Healthy people may be at increased risk for serious complications.|
|Health systems can usually meet public and patient needs.||Health systems may be overwhelmed.|
|Vaccine developed based on known flu strains and available for annual flu season.||Vaccine probably would not be available in the early stages of a pandemic.|
|Adequate supplies of prescription flu medicines are usually available.||Effective prescription flu medicines may be in limited supply.|
|Between 3,000 and 49,000 people in the U.S. die from seasonal flu annually.||Number of deaths could be quite high (eg, US 1918 death toll was approximately 675,000).|
|Symptoms: fever, cough, runny nose, muscle pain. Deaths often caused by complications, such as pneumonia.||Symptoms may be more severe and complications more frequent.|
|Generally causes modest impact on society (eg, some school closings, people who are sick advised to stay home).||May cause major impact on society (eg, widespread restrictions on travel, closing of schools and businesses, cancellation of large public gatherings).|
|Manageable impact on domestic and world economy.||Potential for severe impact on domestic and world economy.|
Adapted from information at flu.gov.
Historically, the 20th century saw three pandemics of influenza, and the 21st has experienced one flu pandemic.
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