Avian Flu FAQs

1. What is Avian Flu?
2. What is Bird Flu?
3. Can Avian flu infect humans?
4. Why is Avian Flu so different from other influenza viruses that affect humans?
5. Where have human cases occurred?
6. How do people become infected?
7. Does the virus spread easily from birds to humans?
8. What needs to happen before the bird flu can be transmitted from human to human?
9. Are there any documented cases of Avian flu being spread from human to human?
10. So if I get the Avian flu, will I die?
11. Is there a vaccine for the Avian flu?
12. What are the symptoms of the Avian flu?
13. Is there any treatment, once the Avian flu virus infects me?
14. What precautions should I take if I am traveling or living outside the United States?

 

Avian flu is an infection caused by avian (bird) influenza (flu) viruses. These flu viruses occur naturally among birds. Wild birds worldwide carry the viruses in their intestines, but usually do not get sick from them. However, bird flu is very contagious among birds and can make some domesticated birds, including chickens, ducks, and turkeys, very sick and can kill them. Like a small number of other bird viruses, including the virus that caused the pandemic of 1918, its genetic material (DNA) has been altered in such a way that it is capable of infecting humans.

Bird Flu is a common name for Avian Flu. The names are used interchangeably.

Avian flu viruses do not usually infect humans, but several cases of human infection with bird flu viruses have occurred since 1997.

Historically, when a virus that primarily infects animals has a genetic change that enables it to infect humans, it causes more problems than the usual strains of influenza virus that infect humans. This is because there is no natural immunity among the human population.

In the current outbreak, laboratory-confirmed human cases have been reported in Cambodia, Indonesia, Thailand, Vietnam, and China. Hong Kong has experienced two outbreaks in the past. In 1997, in the first recorded instance of human infection with H5N1, the virus infected 18 people and killed 6 of them. In early 2003, the virus caused two infections, with one death, in a Hong Kong family with a recent travel history to southern China.

Direct contact with infected poultry, or surfaces and objects contaminated by their feces, is presently considered the main route of human infection. To date, most human cases have occurred in rural areas where many households keep small poultry flocks, which often roam freely, sometimes entering homes or sharing outdoor areas where children play. As infected birds shed large quantities of virus in their feces, opportunities for exposure to infected droppings or to environments contaminated by the virus are abundant under such conditions. Moreover, because many households in Asia depend on poultry for income and food, many families sell or slaughter and consume birds when signs of illness appear in a flock, and this practice has proved difficult to change. Exposure is considered most likely during slaughter, defeathering, butchering, and preparation of poultry for cooking. There is no evidence that properly cooked poultry or eggs can be a source of infection.

No. Though more than 200 human cases have occurred in the current outbreak, this is a small number compared with the huge number of birds affected and the numerous associated opportunities for human exposure, especially in areas where backyard flocks are common. It is not presently understood why some people, and not others, become infected following similar exposures.

Scientists maintain that the current H5N1 virus must change, or mutate, in order for transmission to occur easily from human to human. For this to occur, one of two things must happen: 1) the virus must mutate spontaneously to become more virulent for humans (called antigenic drift), or 2) the virus must infect an animal that is also susceptible to human viruses, such as a pig. As both viruses multiply inside the animal, genetic material from the bird flu and the human flu viruses mix. In the process, a new virus that is capable of being transmitted easily among humans, but also has the features of the bird flu virus, emerges and causes a pandemic. This process is called antigenic shift, and is believed to have led to the pandemics of the 20th century.

So far, the spread of the Avian flu virus from person to person has been rare, and has not continued beyond one person. Scientists are concerned, however, that since there is no natural immunity among humans and the Avian flu virus has the ability to change, it could become more contagious among humans.

Thus far, the Bird flu that has infected humans has been much more serious than the normal influenza viruses that infect humans each year on a seasonal basis. Typically, the death rate from influenza is only 1-2%, and it is older, chronically ill patients that are the most susceptible. The death rate from the current bird flu strain H5N1 exceeds 50%. The most alarming fact is that many of the most seriously affected are previously healthy children and young adults. Scientists suggest the reason for this is that the young have the least natural immunity to new virus strains.

No. Developing a vaccine takes months, sometimes years. Scientists first started working on a vaccine in April, 2005, so there has not been enough time to develop the vaccine. The other challenge is that all strains of influenza virus have a propensity to mutate (i.e. change their genetic material), presenting an even more formidable task to scientists.

Usually the same symptoms as for any influenza virus. Fever, headache, non productive cough, and muscle aching predominate. Those who become very ill often succumb to pneumonia and the secondary effects of the infection.

Perhaps, but you must start taking the medication within the first day or two of symptoms. There are a handful of antiviral agents available for the influenza virus. They are not as effective as antibiotics that are taken for bacterial infections, but can reduce the severity and length of symptoms. In addition, two of the more common drugs used to treat the flu, amantadine and ramandatine, do not work for the Avian flu. The two antiviral agents that may still be effective are Oseltamivar (Tamiflu) and Zanamivar (Relenza)

The CDC has not recommended that the general public avoid travel to any of the countries affected by Avian Flu (H5N1). Persons visiting areas with reports of outbreaks of Avian Flu among poultry or reports of Avian Flu cases in humans can reduce their risk of infection by observing the following measures:

Before any international travel to an area affected by H5N1 avian influenza

• Visit CDC's Travelers' Health Web page on Southeast Asia at http://wwwn.cdc.gov/travel/regionSoutheastAsia.aspx to educate yourself and others who may be traveling with you about any disease risks and CDC health recommendations for international travel in areas you plan to visit. For a list of affected areas and other information about avian influenza, see this website: www.cdc.gov/flu/avian/index.htm.
• Be sure you are up to date with all your vaccinations, and see your doctor or health-care provider, ideally 4-6 weeks before travel, to get any additional vaccination medications or information you may need.
• Assemble a travel health kit containing basic first aid and medical supplies. Be sure to include a thermometer and alcohol-based hand gel for hand hygiene. See the Travelers Health Kit page in Health Infomation for International Travel for other suggested items.
• Identify in-country health-care resources in advance of your trip.
• Make sure that your health insurance plan covers healthcare and medical evacuation outside the United States. HTH Worldwide offers insurance plans for short-term or long-term travel, including access to contracted doctors and hospitals in 180 countries - see www.hthworldwide.com

During travel to an affected area

• Avoid all direct contact with poultry, including touching well-appearing, sick, or dead chickens and ducks. Avoid places such as poultry farms and bird markets where live poultry are raised or kept, and avoid handling surfaces contaminated with poultry feces or secretions.
• As with other infectious illnesses, one of the most important preventive practices is careful and frequent handwashing. Cleaning your hands often with soap and water removes potentially infectious material from your skin and helps prevent disease transmission. Waterless alcohol-based hand gels may be used when soap is not available and hands are not visibly soiled.
• Influenza viruses are destroyed by heat; therefore, as a precaution, all foods from poultry, including eggs and poultry blood, should be thoroughly cooked.
• If you become sick with symptoms such as a fever, difficulty breathing, or cough, or with any illness that requires prompt medical attention, seek medical care immediately.

After your return

• Monitor your health for 10 days.
• If you become ill with fever and develop a cough or difficulty breathing or if you develop any illness during this 10-day period, consult a health-care provider.
  Before you visit a health-care setting, tell the provider the following:
  1. your symptoms,
  2. where you traveled, and
  3. if you have had direct contact with poultry.
  This way, he or she can be aware that you have traveled to an area reporting avian influenza.