Pigs ?, Birds ?, Humans ? or Viruses ?

The 1918 flu pandemic (commonly referred to as the Spanish flu) was an influenza pandemic that spread to nearly every part of the world. It was caused by an unusually virulent and deadly Influenza A virus strain of subtype H1N1.
It is estimated that anywhere from 20 to 100 million people were killed worldwide, or the approximate equivalent of one third of the population of Europe. ( Wikipedia “1918 Flue pandemic” http://en.wikipedia.org/wiki/1918_flu_pandemic ).

The total number of casualties in World War I, both military and civilian, were about 37 million: 16 million deaths and 21 million wounded. The total number of deaths includes 9.7 million military personnel and about 6.8 million civilians. The Entente Powers (also known as the Allies) lost 5.7 million soldiers and the Central Powers about 4 million. Wikipedia “World war I casualties” http://en.wikipedia.org/wiki/World_War_I_casualties

Not pigs, not birds and not humans. It is the virus (H1N1), Damn virus killing more people than world war I casualties.