Pandemic Influenza

Frequently Asked Questions

General Questions

What is a pandemic?

A pandemic is a worldwide outbreak of disease that happens when a new virus emerges and infects people, causes severe illness and death, and spreads easily from person to person.

In the last century, there have been three influenza pandemics: in 1918, 1957 and 1968. The 1918 pandemic (also called "Spanish Flu") was severe.

What’s the difference between pandemic and seasonal flu?

Influenza pandemics are caused by the emergence of a virus that is “novel” (brand new) or radically different from flu viruses that have spread in the past. Because people have little or no resistance to the new virus, and there is no vaccine ready-made to match the new virus, a pandemic results in more severe illness and more death than the common flu we are used to.

Seasonal flu outbreaks are caused by small changes in common influenza viruses. Even though these viruses may change slightly from one year to the next, many people have some immunity. Because similar flu viruses have been around in the past, vaccine can be made to match as closely as possible the flu virus that is expected for the next flu season – before the flu season starts.

When will the next pandemic occur?

No one can predict when a pandemic might start, but scientists and public health experts are watching the H5N1 situation overseas very closely. Governments around the world are preparing for the possibility that this virus may change to a form that spreads more easily from person to person.

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H5N1 Avian Influenza

Is the H5N1 bird flu a pandemic?

No. The current outbreak of H5N1 bird flu is a disease of birds that has made some people sick, but it is not a human pandemic. Bird flu would have to change form (mutate) to become pandemic flu. We don't know if that will ever happen.

Why is the H5N1 bird flu such a concern?

Although scientists cannot predict when the next pandemic will start, or what strain of flu virus will cause it, the continued spread of the H5N1 strain of avian influenza in birds across Asia and into Europe is being closely watched.

H5N1 is a serious concern because:

Is H5N1 bird flu virus the only avian influenza of concern?

Right now, the H5N1 virus is the greatest threat for pandemic. However, other strains of bird flu have also infected people in recent years and have the potential to cause to a pandemic.

Will the H5N1 bird flu virus cause the next pandemic?

Scientists cannot predict whether the H5N1 avian influenza virus will cause a pandemic. But federal, state and local health officials are working with their counterparts throughout the world to track H5N1 as it occurs in birds, and to watch for possible human cases.

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Is there a pandemic influenza vaccine?

No. Federal officials have contracted with a manufacturer to produce a small supply of human vaccine against H5N1 bird flu, and clinical trials are underway. The vaccine might not be effective if the H5N1 virus changes to a form that more easily infects humans, and H5N1 may not become pandemic influenza.

Why isn’t there a vaccine available?

Large amounts of vaccine cannot be made before knowing exactly which virus would be the cause of a pandemic. Production of new vaccine takes about six months.

Can a regular flu shot protect you from bird flu or pandemic flu?

No. Current flu vaccines will not protect against a new pandemic strain of influenza virus.

Can I get the pandemic influenza vaccine once it is developed?

Very few people would be able to get vaccinated at first. If a pandemic starts, federal, state and local governments will work with partner groups to make specific recommendations on the early use of vaccine. Current recommendations are to use limited vaccine supplies for health care workers and people at highest risk of death. Over time, as more vaccine is produced, more people would be vaccinated.

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Antiviral Medications

What are influenza antiviral medications?

These are prescription drugs that can make symptoms less severe and shorten the length of time people are sick. The drugs may also make a person less likely to spread influenza to others. To be effective, they must be taken within two days of becoming sick. Some antiviral medications may also be used to prevent influenza.

Which antiviral medications would be used if the H5N1 bird flu became a human pandemic?

At this time, Tamiflu and Relenza are the most likely antiviral medications to be used in a pandemic caused by the H5N1 virus. The effectiveness of these antivirals would vary depending on how resistant the virus is to one or more of the medications.

Are there enough antiviral medications for everyone if a pandemic happened now? If not, who will get them?

Although the government is stockpiling antiviral medications, at this time there are not enough for everyone. The federal government has made recommendations about who will be the first to get antiviral medications based on their risk, their role in fighting the pandemic, and the severity of the illness. Discussion continues about the best way to allocate these medications.

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Preparing for an Influenza Pandemic

What effect would a pandemic have on our communities?

The effects of a pandemic could be severe. Many people could be sick at the same time and be unable to go to work. Many people might have to stay at home to care for sick family members. Schools and businesses might close for a time to try to reduce the spread of disease. Basic supplies, medications and services could be limited. Large group gatherings might be canceled. These are examples of challenges that must be considered as we plan for a pandemic response.

What can I do to prepare for a possible pandemic?

Plan ahead for situations in which you might have to take care of yourself and your family without leaving home. Think about essential supplies, like food and medicine, that you and your family might need. The more you know now, the more you can help your family and community prepare. Individual and family preparedness guides and planning checklists are available to help you get started.

What can I do to keep from getting or spreading flu?

We can all learn to decrease the spread of disease by taking a few simple precautions every day, and by reinforcing these behaviors among family and friends.

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Last update June 2008

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