Avian flu is a form of influenza that often kills domesticated poultry such as chickens and turkeys. Some strains of bird flu can make humans sick, too. The most dangerous is H5N1, which has caused at least 10 human deaths during the current outbreak. H5N1 first jumped the species barrier from birds to humans in Hong Kong in 1997, when six out of 18 infected people died. The fear is that H5N1 could combine with a human-flu strain to create a deadly virus that's so contagious it could cause a human pandemic.
What caused this outbreak?
One theory is that wild waterfowl (the natural hosts of avian-flu viruses) have spread the virus while migrating across Asia. Live-bird markets may also have played a key role in spreading avian flu, with domesticated poultry excreting the virus, for at least 10 days, in their mucus and feces.
How can you protect yourself?
The people most at risk are those who work with live infected poultry. If you stay away from chicken farms and live-bird markets in areas where avian flu is rife, the odds of infection are minimal.
Can you eat chicken or duck?
Yes. Avian flu is not a food-borne virus, so eating poultry is safe. Buy frozen, processed poultry products, and cook them thoroughly because heat kills flu viruses. Cooked eggs are O.K., too.
What are the symptoms if you catch bird flu?
They range from fever, sore throat, cough, and muscle aches to eye infections, pneumonia, and acute respiratory distress.
How is bird flu treated?
Antiviral drugs such as amantadine and rimantadine are effective against some strains of flu, but the current virus sweeping Asia keeps mutating and appears resistant to these cheaper drugs. It's believed that pricier drugs such as Tamiflu will prove more effective, but supplies are limited. Meanwhile, it may take at least six months to produce a vaccine that's effective against H5N1.
How scared should you be?
All of the human victims so far caught the virus from exposure to infected chickens. There's no evidence yet that bird flu is being spread from humans to humans, which would make this virus infinitely more ominous. Should that occur, experts warn of a global pandemic far worse than SARS, which killed 800 people worldwide. Mutating viruses are frighteningly unpredictable, but mass cullings of poultry should help to avert a pandemic.