The 1918 influenza pandemic was commonly called "Spanish flu." However, the pandemic didn't originate in Spain, nor was it more virulent there than elsewhere. It is called the Spanish flu because, Spain being a neutral country, its press was not censored and news of the effects of the pandemic upon Spain was readily available. What made the pandemic virus particularly lethal was the response that it provoked in the immune system. Because of this, healthy people with strong immune systems were more likely to die than those with weaker immune systems. As most soldiers would be in the former category, they were hit hard, especially beginning in August 1918, and many who had survived four years of fighting were cut down by the epidemic. The influenza epidemic would end up killing 20,000,000 people worldwide, more than who had died in the First World War.