What is Bird Flu?

Avian influenza (or bird flu) is an illness caused by influenza viruses that occur naturally in wild birds. The H5N1 strain of the virus is deadly to domestic birds and may be transmitted from birds to humans.

Wild birds worldwide carry avian influenza viruses in their intestines, but usually do not get sick from them. The viruses are very contagious among birds and can make some domesticated birds, including chickens, ducks, and turkeys, very sick and kill them.

Infected birds release influenza virus in their saliva, nasal secretions, and feces. Domesticated birds may become infected with avian influenza virus through direct contact with infected birds or through contact with surfaces or materials that have been contaminated.</p>

Bird flu infection in domestic poultry causes two main forms of disease, low pathogenic and high pathogenic. The low pathogenic form may go undetected and causes only mild symptoms, like ruffled feathers and a drop in egg production. The high pathogenic form spreads quickly and may cause disease that affects internal organs.  Between 90 and 100% of domestic fowl infected with the high pathogenic strain die within 48 hours.

Since 2003, a growing number of human H5N1 cases have been reported in Azerbaijan, Cambodia, China, Djibouti, Egypt, Indonesia, Iraq, Thailand, Turkey, and Vietnam. Almost all of these cases resulted from exposure to infected poultry, and more than half of the people infected with the virus have died.

It is important to understand the difference between avian flu and seasonal flu (or common flu). Most people have some resistance to strains of common flu, and vaccines are available.  Because H5N1 is new to humans, they have no immunity, and there is no vaccine available.

The types of influenza viruses currently circulating among humans, H1N1, H1N2 and H3N2, probably originally came from birds. These influenza viruses are constantly changing, and other strains might change over time and then be able to infect and spread among humans.

Health professionals are concerned about the spread of avian H5N1 virus and believe that it represents a threat to human health.

The virus is believed to pose a serious threat to humans because:

• It is very powerful
• It is being spread by migratory birds
• It can be transmitted from birds to mammals and in some limited circumstances to humans
• It continues to evolve

So far, there has been no human-to-human transmission of the disease, experts are concerned that H5N1 will evolve into a virus capable of human-to-human transmission.

Who is most likely to be affected by bird flu?

Currently humans have a very low possibility of catching avian influenza.  Viruses do not usually infect people, and the H5N1 strain is one of the few that has crossed the barrier from animals to humans; it is also the most deadly.

Most of the cases of H5N1 infection that have infected humans have come from contact with sick domesticated chicken, ducks and turkey or with surfaces contaminated with their secretions.

In the current outbreaks in Asia, Europe, and Africa, more than half of those infected with the H5N1 virus have died, and most of the cases have appeared in previously healthy children and young adults. It is possible, however, that only seriously ill individuals have reported their cases and that the full extent of H5N1 virus is not yet known.

What are the symptoms of bird flu?

Symptoms of avian influenza in humans have ranged from typical human flu-like symptoms (fever, cough, sore throat, and muscle aches) to eye infections, pneumonia and severe respiratory diseases and other life-threatening complications. Symptoms of avian influenza depend on which virus caused the infection.

Is bird flu the same as pandemic influenza?

While avian influenza flu is not pandemic flu, bird flu is one of several influenza viruses that have the potential turning into a pandemic (a virulent human flu that causes a global outbreak of serious illness.) Currently, there is no pandemic flu, but experts fear that we may be affected by one at any minute.

During the 20th Century, there were three pandemics, new strains of flu viruses that killed people throughout the world.

The 1918-1919 pandemic was the most severe; it caused at least 675,000 U.S. deaths and up to 50 million deaths worldwide.

The 1957-1958 pandemic was moderately severe, causing at least 70,000 U.S. deaths and 1-2 million deaths worldwide.

The 1968-1969 pandemic was the least severe; it caused at least 34,000 U.S. deaths and 700,000 deaths worldwide .

How is bird flu treated?

The H5N1 virus that has caused human illness and death in Asia is resistant to amantadine and rimantadine, two antiviral medications commonly used to treat huan flu. Two other antiviral medications, oseltamavir and zanamavir, would probably work to treat influenza caused by H5N1 virus, but more studies are needed to test their effectiveness.

Laboratory studies show that some of the medications used to treat the human common flu should work to fight avian influenza in humans. Flu virus can become resistant to these medicines, however, so they may not always work.

Is there a bird flu vaccine?

A pandemic vaccine cannot be produced until a new pandemic influenza virus emerges and is identified. The U.S. Department of Health and Human Services (HHS) and National Institute of Allergy and Infectious Diseases (NIAID) are currently developing pre-pandemic vaccines based on current strains of H5N1. They are also working with industry to increase the country's ability to mass-produce new vaccines.

Are any Americans infected?

Currently, avian influenza has not reached the United States, and no known Americans living abroad have contracted the illness. Researchers continue monitoring the situation, however, so they will be ready should a case arise here.

How can I protect myself from bird flu and pandemic influenza?

As you and your family plan for an influenza pandemic, think about the challenges you might face, particularly if a pandemic is severe.

Some of the possible challenges you might face during a pandemic include:

• The disruption of essential services provided by banks, hospitals, stores and phone companies
• Limited supply of food and water
• Limited transportation services and road closings
• Cancellation of public gatherings like worship services and school

Make a list of phone numbers and keep a small reserve of cash at home. Maintain a stock of medications, baby formula, pet food and any other items you need on a weekly basis. Store up at two weeks of non-perishable food and a gallon of water per person per day. Discuss your company's emergency plan with your employer, and ask schools about their plans.

You can prevent flu strains as well as other illness by following these simple health tips:

• Cover your nose and mouth with a tissue when you cough or sneeze-throw the tissue away immediately after use
• Wash your hands often with soap and water; if you are not near water, use an alcohol-based (60-95%) hand cleaner.
• Avoid close contact with people who are sick, and when you're sick, keep your distance from others
• If you get the flu, stay home
• Stop the spread of germs by avoiding touching your eyes, nose, or mouth.

  To find out more about pandemic influenza, check out www.avianflu.gov, or ask your doctor.