A: The term "bird flu" describes one of several influenza viruses that birds can carry. But several types can also infect humans. These are different in makeup from the usual human flu.
Q: What are the symptoms of bird flu in humans?
A: They can include typical flu-like symptoms, like fever, cough, sore throat and muscle aches, as well as eye infections, pneumonia and severe respiratory illness. At this point, it is believed to have killed at least 60 people, the majority in Vietnam, since 2002.
Q: How do humans get bird flu?
A: Right now, authorities believe there have been cases of humans contracting bird flu primarily from contact with excretions from infected birds. Common victims are people who handle poultry on farms or at live markets. There is one known case of it spreading from one person to another.
Q: Why is bird flu receiving so much attention?
A: A particular type of bird flu, known as H5N1, is seen as a candidate to cause a flu pandemic if it mutates into a form capable of spreading easily from person to person. Because people have not developed immunity to H5N1, unlike the usual strains of human flu, it could have more severe effects on a greater number of people. However, it is also possible that the mutation could create a relatively mild human flu.
Q: Is bird flu the only possible source of a flu pandemic?
A: No. A pandemic could break out should any dramatically different new flu virus emerge. The last century saw three: in 1918, 1957 and 1968. The 1918 pandemic, caused by a bird flu that jumped to humans, killed at least 40 million people; the later outbreaks killed far fewer but still caused widespread disruption.
Fear of a pandemic is also heightened because it has been 37 years since the last one, and some scientists argue that new flu strains capable of causing a pandemic emerge every 30 years or so.
Estimates of the death toll from a new pandemic vary wildly, and depend on the level of organised response to an outbreak. However the World Health Organization consider the moest likely scenario to be a toll between 2 million and 7.4 million people.
Q: How can doctors detect bird flu?
A: With a blood test of a person suspected of having it.
Q: Is there a vaccine for bird flu?
A: Yes. French vaccine maker Sanofi-Pasteur has begun production of a vaccine against H5N1. But researchers have not settled on how large a dose will ensure protection.
If bird flu began spreading widely, scientists would have to check whether that vaccine still would provide protection or a new one would be needed. Other manufacturers are working to produce experimental bird-flu vaccines as well.
Q: Is it part of my flu shot this year?
A: No. The yearly flu shot is composed of vaccines for several varieties of human flu that are expected to be in circulation this winter. Officials expect at least 71 million doses to be available.
Q: So how do I get vaccinated for the bird flu?
A: At the moment, the public can't. It is likely the government would control distribution in the event of an outbreak in an effort to manage its spread.
Q: How is bird flu treated?
A: Two drugs that fight regular flu, Tamiflu and Relenza, are considered to be effective in treating flu caused by H5N1 if administered quickly. They also may help prevent infection. The government plans to stockpile tens of millions of Tamiflu pills, and a smaller supply of the inhaled drug Relenza.
Q: Where is bird flu now?
A: Outbreaks of the H5N1 strain have occurred in poultry in several countries in Asia, and is now moving across Eurasia. More than 150 million birds died from the disease or have been slaughtered to contain its spread.
Source: Centers for Disease Control and Prevention.