The U.S. government has been preparing for pandemic influenza for several years. In November 2005, the President announced the National Strategy for Pandemic Influenza. Ongoing preparations include supporting the efforts of federal, state, tribal and local health agencies, including Emergency Communications, to prepare for and respond to pandemic influenza.

What is pandemic influenza?

Influenza viruses cause infections of the respiratory tract (breathing tubes and lungs). In some persons, complications of influenza can be severe, including pneumonia.

Pandemic influenza is a global outbreak of disease from a new influenza A virus that is unlike past influenza viruses. Because people have not been infected with a similar virus in the past, most or all people will not have any natural immunity (protection) to a new pandemic virus.

How is a pandemic different from regular flu season?

A pandemic flu is a new influenza virus that could be a much more serious flu virus than seen in a typical flu season. Different from the typical strains of flu, humans would have no or little natural resistance to a new strain of influenza. Also, there is a vaccine for seasonal flu, which is prepared each season against new variations of the seasonal influenza. There is no vaccine available at this time for a pandemic flu, and it is expected to take at least six months after a pandemic flu appears to develop a vaccine.

Why is pandemic influenza so serious?

Because most or all people would not have immunity to a new pandemic virus, large numbers of persons around the world can be infected. If the pandemic virus causes severe disease, many people may develop serious illnesses.

Once a pandemic virus develops, it can spread rapidly causing outbreaks around the world. The U.S. Centers for Disease Control and Prevention (CDC) predicts that as much as 25% to 30% of the US population could be affected.

Can pandemic flu be prevented?

Public Health Worcester Metropolitan Medical Response System is working with federal, state, and other local government agencies to respond to pandemic influenza and to maintain essential health care and community services if an outbreak should occur. In fact, governments all around the world are preparing for the possibility of a pandemic outbreak under the leadership of the World Health Organization.

It is not possible to prevent or stop a pandemic once it begins. A person infected with influenza virus can be contagious for 24 hours before the onset of symptoms, and for seven days thereafter, making it extremely easy for the virus to spread rapidly to large numbers of people.

Although the federal government is stockpiling medical supplies and antiviral drugs, no country in the world has enough antiviral drugs to protect all their citizens. Anti-viral drugs can be used to treat severe cases as long as there was a reasonable chance that the drugs might help save lives. Antiviral drugs might also be prioritized for people who work in essential occupations, such as health care workers.

Other strategies for slowing the spread of a severe influenza outbreak could include temporarily closing schools, sports arenas, theaters, restaurants, taverns, and other public gathering places and facilities.

There currently is no vaccine to protect humans against a pandemic influenza virus because the pandemic virus has not yet fully developed. However, vaccine development efforts are under way to protect humans against a pandemic influenza virus that might develop from the current bird flu virus in Asia. (See information on bird flu below).

When is pandemic influenza A expected?

Influenza pandemics occur naturally. There were 3 pandemics in the 20th century. The pandemic of 1918-19 was the most severe pandemic on record, in which 50 million or more persons around the world died, including approximately 650,000 Americans.

It is not possible to predict accurately when influenza pandemics will occur or how severe they will be. However, the current outbreak of avian influenza in Asia has influenza experts concerned that a pandemic is developing that may be severe.

Why does the current bird flu outbreak in Southeast Asia pose a risk of causing a pandemic influenza A outbreak in humans?

New human influenza viruses arise from bird influenza viruses that then change to a form that can infect humans and spread readily from person to person. The current bird flu outbreak in Asia is caused by a type of influenza A virus called "H5N1." The H5N1 outbreak among domestic chickens and ducks in Asia is widespread and uncontrolled. Human infections and deaths due to the avian H5N1 virus have occurred, although the virus has at this time not developed the ability to pass easily from person to person and cause outbreaks in humans.

What are the symptoms of bird flu in humans?

The reported symptoms of bird flu in humans have ranged from typical influenza-like symptoms (e.g., fever, cough, sore throat, and muscle aches) to eye infections (conjunctivitis), pneumonia, acute respiratory distress, viral pneumonia, and other severe and life-threatening complications.

What can the public do to reduce their risk of pandemic influenza?

Stay informed. These provide regularly updated information about bird flu and pandemic flu:

Pandemic Influenza Planning: Guide for Individuals and Families. The guide includes checklists and information on how to prepare for a potential pandemic.
For information on the vaccine development process, visit National Institutes of Health.

Stop germs from spreading.

Stay home when you are sick.
Cover your mouth and nose with tissue when coughing and sneezing.
Wash your hands often. The key is to wash thoroughly with warm water, and to wash frequently.
When hand washing is not possible, use an alcohol based hand cleaner.
Avoid touching your mouth, nose and eyes.

How is pandemic influenza spread?

Pandemic influenza would be spread from person to person primarily through "respiratory secretions," the same way seasonal influenza viruses and other common respiratory infections spread. Respiratory secretions are virus-containing droplets (such as spit or mucous) that are spread when infected persons cough or sneeze. These droplets can then land on the surfaces of the mouth, nose, and throat of persons who are near (i.e., within 3 feet) the ill person. The virus may also be spread through contact with the infectious respiratory secretions on the hands of an infected person and other objects and surfaces.

Adults can spread influenza virus one day before symptoms appear and up to five days after the onset of illness.

Will the regular (seasonal) flu shot provide any protection against the pandemic influenza virus?

Probably not. But the regular flu shot will protect you against the influenza viruses that are circulating right now.

What is the U.S. government doing to prepare for pandemic influenza?

Working with the World Health Organization (WHO) and with other nations to help detect human cases of bird flu and contain a flu pandemic, if one begins.
Supporting the manufacturing and testing of influenza vaccines, including finding more reliable and quicker ways to make large quantities of vaccines.
Developing a national stockpile of antiviral drugs to help treat and control the spread of disease.
Supporting the efforts of federal, state, tribal and local health agencies to prepare for and respond to pandemic influenza.
Working with federal agencies to prepare and to encourage communities, businesses and organizations to plan for pandemic influenza.