I reported on bird flu -- or technically Avian Influenza -- on the NBC5 News at 11 a.m. Friday. Since then, the questions have poured in. Here are some of them:

What exactly is bird flu?
Bird flu is a viral infection carried by wild birds. It has now spread to domesticated birds and has killed over 100 million of them. Now the bird flu virus has shown it can easily mutate and in some instances make a direct jump from birds to people. Thee have been at least 100 human cases mainly in the far east with the most case occurring in Vietnam.

When did the first human case occur?
1997

Why is bird flu different from regular flu?
Bird flu is genetically different and much more lethal with over half the victims dying. The most deadly type of bird flu virus is H5N1 and it is very similar genetically to the 1918 Spanish Flu that killed 59 million worldwide.

What are the symptoms?
They are similar to conventional flu with cough, high fever, sore throat, muscle pains and severe fatigue. Over half the bird flu patients died of pneumonia and acute respiratory distress.

How can you tell regular flu from bird flu at the beginning?
The path of the flu outbreaks will be tracked. Also a blood test can tell the difference.

Has there been a case of bird flu in the United States?
There has been no bird flu cases found to date in the United States.

How does one catch bird flu?
Right now the greatest exposure is from contact with infected domesticated birds, particularly in Southeast Asia. Yesterday 3 infected birds were found in Romania. The virus can travel short distances through the air and it can be transmitted by touching infected birds or bird droppings or feathers. The source does not need to be alive. A few cases have come from person to person transmission and this raises the fear that an epidemic could break out.

Does freezing destroy the virus?
No. In fact. the 1918 virus was cultured for study from a 1918 flu victim that was frozen in Permafrost. Bird flu virus was also found and cultured from frozen duck meat.

Is there a bird flu vaccine?
A bird flu vaccine was successfully tested this August in healthy adults. It worked. Further testing is needed and it will be an enormous challenge to manufacture enough for everyone.

Do anti-flu drugs work?
So far the anti-flu drugs, Tamiflu and Relenza do seem to work to lessen the severity of the bird flu, but there is concern they might lose some of their effectiveness in an epidemic.

Does this year's flu shot protect against bird flu?
No, but it's important to get it since about 10 percent of us get the flu and there are 36,000 deaths from it every year.

What can I do to protect myself from the bird flu?
As I mentioned, avoid domesticated birds especially fowl in the far east. Always use careful frequent hand washing. Although bird flu has not been detected here, use special care in handling poultry. Wash everything coming in contact with it. Cook all poultry to 180 F.