As easy as ABC...
There are three types of the influenza virus, called A, B and C.
Influenza A and B are the real baddies. Catching these can make you severely ill, whereas type-C flu will only ever give you mild symptoms.
Influenza A is causing the current bird-flu problems and was behind all the worlds' flu pandemics. In total it has killed tens of millions of people worldwide.
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H5N1 bird flu virus could be the first 21st century pandemic.
Image: Centre for Disease Control |
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