Flu: an ancient killer
Explosive and deadly outbreaks of flu have been recorded thoughout time, probably starting in ancient cities where people and animals lived crowded together.
We've been keeping track of world flu pandemics since the 1700s. There's been an average of three pandemics every century and the 1900s were no exception.
Scientists have looked at these most recent viral killers to try and learn some lessons that will help us fight the current bird-flu pandemic threat.
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| People keep chickens, and other animals near their homes in many parts of Asia. |
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