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Pandemic Flu

What is Pandemic Influenza (Flu)


Pandemic flu is like seasonal flu but much worse. It is a global flu outbreak that occurs when a new influenza virus emerges for which there is little or no immunity in the human population. This strain of influenza virus begins to cause serious illness and then spreads easily from person to person across the world. In the past, all flu pandemics have originated from bird flu viruses. Key features of a pandemic influenza virus are:


  • It is so new and different that no one has immunity to the virus
  • It spreads easily from one person to another
  • It is able to infect many people around the world
  • It can cause severe illness and/or death


Just like with earthquakes, experts believe another pandemic is inevitable, but they are unable to predict when it will occur.


Previous Flu Pandemics

Flu pandemics have occurred in the past. There were three in the 20th century. The most severe flu pandemic occurred in 1918, during which healthy young adults were the most sick. Approximately 40 - 50 million people died worldwide. Less severe flu pandemics occurred in 1957 and 1968.


How Could a Pandemic Flu Affect our Community

A pandemic flu could last many months and up to 2 years. During this time, it could cause:


  • Illness in approximately 30% of our population - and many deaths
  • Up to 50% of people to miss work
  • Shortages in routine supplies and services
  • Dismissal of children from school
  • Hospitals and clinics to be stressed or overwhelmed
  • Cancellation of large public gatherings


Although we can't stop pandemic flu once it starts, by preparing now, we can slow the spread and minimize the effects.


How San Francisco is Preparing

San Francisco is closely monitoring avian influenza and preparing for a pandemic in our region. A San Francisco City Department Pandemic Influenza Task Force is coordinating planning to ensure a multi-disciplined response. The health department is also reaching out to hospitals and clinicians, front line workers, businesses, organizations that meet the needs of special populations, and the general public. For more information see the fact sheet Pandemic Influenza: San Francisco City & County Preparedness.


How Individuals and Families can Prepare

San Francisco is working hard to protect our community. Make sure you are ready too. Here are some simple steps you can take to prepare yourself, your family, and your home for pandemic flu:



Additional Information


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