Reference Article
Spanish flu
The Spanish Flu Pandemic, also known as La Grippe Espagnole, or La Pesadilla, was an unusually severe and deadly strain of avian influenza, a viral infectious disease, that killed some 50 million to 100 million people worldwide over about a year in 1918 and 1919 [1].
It is thought to have been one of the most deadly pandemics so far in human history.
It was caused by the H1N1 type of influenza virus, which is similar to bird flu of today, mainly H5N1 and H5N2.
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