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AVIAN INFLUENZA (H5N1) - Frequently asked questions
May 30, 2006
The ABC movie, "Fatal Contact: Bird Flu in America," dramatically explores the fictitious impact of a worst -case scenario of human flu pandemic in the United States and around the globe.
To ensure you have the facts about bird flu and wild birds, Department of the Interior (DOI) scientists have prepared a list of important flu facts, answers to common questions about bird flu, and provided links to more detailed information. It is important to stay informed of the ever-changing status of bird flu and the risks these viruses pose to people, domestic poultry, and wildlife.
Influenza pandemics are caused by the global spread of a new influenza virus that has adapted to humans and is easily transmitted from person to person.
There is currently no human influenza pandemic occurring anywhere in the world.
At present, the current H5N1 bird flu virus does not easily infect people and rarely spreads from person to person.
Scientists are concerned that H5N1, or another strain of influenza, could mutate to become a human flu virus that is easily transmitted from person to person and this could trigger an influenza pandemic.
The U.S. National Strategy for Pandemic Influenza is guiding the U.S. preparedness and response to an influenza pandemic, with the three goals of Preparedness and Communication; Surveillance and Detection; and Response and Containment.
For more information about pandemic flu and human influenza, visit:
The U.S. Government's pandemic and avian flu Web site
The Centers for Disease Control and Prevention Web site
The World Health Organization's Web site
Avian influenza is a common disease of birds that rarely infects humans.
Avian influenza viruses are classified as having low pathogenicity or high pathogenicity based on the severity of the illness they cause in poultry, and most are not considered a public health threat.
Highly pathogenic strains, like highly pathogenic H5N1, cause severe illness and rapid death in poultry.
Migratory birds-typically waterfowl, shorebirds, gulls and terns-are natural carriers of avian influenza, and are considered the natural reservoir for low-pathogenic strains of the disease.
Most human cases of avian influenza have occurred in people with close contact with infected poultry.
Avian influenza, including the highly pathogenic H5N1 strain, does not easily infect humans.
When the H5N1 strain has infected humans, it is a very serious disease; while only about 200 people are known to have contracted the disease, about half of them have died.
Person-to-person transmission of avian influenza, including the H5N1 strain, is extremely rare.
The highly pathogenic H5N1 strain has spread to large geographic areas in Asia, Europe, and Africa where it has primarily affected domestic poultry.
H5N1 has caused the largest and most severe outbreaks in poultry on record.
Legal and illegal movement of infected birds, poultry products, contaminated materials, equipment, and vehicles, as well as wild bird migration are the most likely ways that H5N1 is spread.
H5N1 has been eliminated from countries such as Japan, South Korea, and Israel by quick and efficient eradication of the disease in domestic poultry.
For more information on avian influenza in domestic animals go to the U.S. Department of Agriculture Avian Influenza Web page.
The highly pathogenic H5N1 strain of avian influenza has not been detected in North America.
Federal and state domestic animal, wildlife, and public health agencies are working closely to prepare, prevent and respond to the potential introduction of highly pathogenic H5N1 virus into the United States.
If the highly pathogenic H5N1 is detected in wild birds in the United States it does not necessarily pose a threat to U.S. poultry industry or to the general public.
Should the current H5N1 be detected in North America it will not signal the start of a flu pandemic
The U.S. Departments of Interior, Agriculture and Health and Human Services are working with other federal and state agencies in implementing a National Early Detection System for Highly Pathogenic H5N1 Avian Influenza in Wild Migratory Birds focused on:
Rapid investigation of wild bird mortality in the U.S.
Surveillance in live wild birds
Surveillance in hunter-killed wild birds
The use of sentinel species to detect H5N1
Environmental sampling of areas frequented by wild birds
The impact of highly pathogenic H5N1 on migratory birds and the role that wild birds play in the spread of H5N1 is unclear.
Highly pathogenic H5N1 has been detected in an increasing number of wild bird species; however the numbers of wild birds infected with H5N1 has been relatively low.
In many cases, scientists are uncertain if wild birds were the source of the H5N1 virus or if they acquired it from poultry, although once infected, wild birds could transport the virus to a new location.
There is currently no scientific basis for controlling highly pathogenic H5N1 by management of wild birds beyond physically segregating poultry from exposure to wild birds.
For more information about avian influenza and H5N1 in wild birds go to:
U.S. Department of the Interior's Avian Influenza
USGS Alaska Science Center
Wildlife Disease Information Node
Alaska Pandemic Flu webpage
Hunters should follow routine precautions when handling game.
Do not handle or eat sick game.
Wear rubber or disposable latex gloves while handling and cleaning game, wash hands and thoroughly clean knives, equipment and surfaces that come in contact with game.
Do not eat, drink, or smoke while handling animals.
All game and poultry products should be thoroughly cooked (well done or 160o F).
For more safety information on avian influenza:
Alaska Hunter Fact Sheet
World Health Organization Safe Food Preparation Guide
March 23
What is avian influenza?
Avian influenza, or "bird flu", is a contagious disease caused by influenza viruses that normally infect only birds, but occasionally also other animals. Domestic poultry is especially vulnerable to infections. It can cause large outbreaks associated with high mortality. In these instances the term “highly pathogenic avian influenza” (HPAI) is used. Outbreaks in poultry may spread rapidly.
What is A(H5N1)?
A(H5N1) is a highly pathogenic strain of bird flu virus that is currently causing epizootics among poultry in South East Asia, and has been detected in Croatia, Russia, Romania and Turkey. The diagnosis can only be made by laboratory tests and must be confirmed in one of the international reference laboratories where the virus is further characterized. Characterization can take up to two weeks, which therefore could also be the time needed to confirm the disease as being caused by the highly pathogenic avian influenza A(H5N1) virus.
What do the A, the H and the N in A(H5N1) stand for?
Influenza viruses are divided in three types: A, B, and C. Type A viruses infect mammals (among which humans) and birds. Type B and C viruses infect humans only. Type A and B viruses cause the so called “flu”. Type C viruses cause milder respiratory symptoms. Type A influenza viruses are further subdivided into 16 hemagglutinin subtypes (H1-H16) and 9 neuraminidase subtypes (N1-N9). For further information click here.
What is the risk for the general public?
The risk for people is very small. The A(H5N1) virus that has been circulating since 1997 in Asia, is very aggressive, but does not transmit easily from animal to humans. To date (January 2006) 184 human cases have been reported (in Cambodia, China, Indonesia, Thailand, Turkey and Viet Nam), and all were in very close contact with infected poultry. Of them 103 died. For up-to-date numbers click here. Fortunately, the present virus does not transmit easily from person-to-person.
The threat of the A(H5N1) virus to the general public comes from the following mechanism. First, the A(H5N1) virus may recombine with a human influenza virus. This process of gene reassortment inside the human body can give rise to a completely new subtype of the influenza virus. This can also take place in pigs as pigs can be infected with human as well as avian influenza viruses. Second, the A(H5N1) virus may adapt directly to the human host. In both instances, few, if any, humans would have natural immunity to this new influenza virus.
The worst-case scenario is that this new virus will be easily transmitted from person-to-person and will have a high mortality. This new virus could be capable of infecting many people and could cause a worldwide epidemic (pandemic) with serious consequences. Therefore, the World Health Organization, the European Commission, the European Centre for Disease Prevention and Control and national authorities, are all actively involved in the prevention of transmission from infected animals to humans. In addition, there is a close collaboration between those people specialized in Human and Animal health.
Is there a vaccine against H5N1 in humans?
No. Currently available vaccines will not protect against disease caused by the A(H5N1) strain in humans. The WHO and many other organizations worldwide are working towards producing a vaccine against avian A(H5N1) influenza. Candidate vaccines have been produced, which are being evaluated in humans. However mass production of a vaccine will probably not take place unless there is evidence of efficient spread between humans.
Will normal seasonal influenza vaccine protect me against avian influenza?
The normal seasonal influenza vaccine provides protection against currently circulating strains of human influenza. It does not provide protection against avian influenza A(H5N1). In the event of an influenza pandemic, a new vaccine would need to be produced.
Are drugs available for prevention (prophylaxis) and treatment?
Two licensed modern virus inhibitors (neuraminidase inhibitors) exist: oseltamivir (Tamiflu®) and zanamivir (Relenza®) exist. Both have demonstrated, under laboratory conditions, to be effective against the current A(H5N1) virus. They reduce spreading of the virus and help to diminish the symptoms of influenza. In many European countries the national governments already have a stock of these drugs and have placed orders to ensure sufficient quantities.
Can I go on holiday to the affected areas?
There is no negative travel advice for the affected countries due to the bird flu. But people are recommended to stay away from poultry markets and animal farms for children.
How did the avian flu spread from Asia to Europe?
The disease can spread from country to country through international trade in live poultry. The current opinion is that migratory birds could possibly carry the virus for long distances. Their role in spreading of low pathogenic avian influenza is confirmed, but their role in the spread of Highly Pathogenic Avian Influenza A(H5N1) is less clear. Wild ducks are the natural reservoir of bird flu viruses. These birds develop only mild and short-lived illness themselves. They could carry the virus over great distances, and excrete it in their droppings, as such spreading the virus to other areas. Chickens, domestic ducks, turkeys, geese, and several other species raised on farms are susceptible to this virus that causes lethal infections.
Another way Highly Pathogenic Avian Influenza can be spread is by the movement of commercially kept birds, movements of waste products of birds, by contaminated clothes of people moving from farm to farm and by smuggling of infected birds. This is why bio-security is so important.
Can a pandemic be averted?
No one knows for sure. Influenza viruses are highly unstable and their behavior cannot be predicted. The most important part of prevention is to reduce opportunities for human exposure to the largest reservoir of the virus: infected poultry. This is achieved through the rapid detection of poultry outbreaks and the introduction of emergency control measures, including the destruction of all infected or exposed poultry stock, and the proper disposal of carcasses. The rapid culling of all infected poultry, as happened in Hong Kong in 1997 [A(H5N1)] and in the Netherlands in 2003 [A(H7N7)], is thought by many influenza experts to have averted an influenza pandemic in humans. In the current situation, the focus is therefore on rapid intervention in infected poultry farms, together with proper protection measures for the people in close contact with the infected animals.
What is the current situation in North America?
Highly pathogenic H5N1 has not been reported in North America, although Low Pathogenic H5N1 has been reported in two birds from the mid-west (Minnesota several years ago, and Manitoba, last year). No known cases of humans contracting H5N1 have been reported in North America.
What evidence is there that hunters can be infected if they are exposed to wild birds?
None; there has not been a reported case of a human contracting the disease from a wild bird any where in the world. (Nevertheless, it is theoretically feasible).
What is AWA doing to address the Avian Flu threat to Alabama hunting?
AWA is encouraging caution to excessive reaction to the Avian Flu threat, but we will be involved in early detection efforts and advocate responsible hygiene to our members.
Links
PBS Video on Avian Flu
More from the World Health Organization
Credits for much of this information is to California Waterfowl Associtation
Some excerpts borrowed from the European Influenza Surveillance Scheme.
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