A Worldwide Travel Notice has been issued to travelers about the resurgence of bird flu, though it is in its mild stages.

Countries all around the world have reported cases of H5N1 (avian influenza), or bird flu, as it is widely known.

H5N1 commonly causes sickness in birds, but it has a tendency to hit humans as well. Bird flu can deteriorate a person's heath very quickly, and can make them very sick. The Influenza has a 50% mortality rate.

Experts say that even though H5N1 transmission in humans does not occur easily, it still continues to be a threat, especially if it mixes with the H1N1 swine flu virus, which is dominant all over the world.

It was recently reported that a 3 year old girl succumbed to H5N1, making her the second fatality in Vietnam this year to the virus.

The infant used to live near an illegal poultry slaughterhouse in Binh Duong. Since 2003, bird flu has proved to be fatal for 58 people in Vietnam.

In terms of deaths, Indonesia has been the worst hit by bird flu, which has claimed 135 lives.