| Seasonal Flu | Pandemic Flu |
| Outbreaks follow predictable seasonal patterns; occurs annually, usually in winter, in temperate climates | Occurs rarely (three times in 20th century - last in 1968) |
| Usually some immunity built up from previous exposure | No previous exposure; little or no pre-existing 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 antivirals are usually available | Effective antivirals may be in limited supply |
| Average U.S. deaths approximately 36,000/yr | Number of deaths could be quite high (e.g., U.S. 1918 death toll approximately 500,000 see link below) |
| 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 (e.g., some school closing, encouragement of people who are sick to stay home) | May cause major impact on society (e.g. widespread restrictions on travel, closings 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 |
For more information go to: http://www.pandemicflu.gov
Please note: