How many people became infected with the Spanish Flu?
Spanish flu
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This huge death toll was caused by an extremely high infection rate of up to 50% and the extreme severity of the symptoms, suspected to be caused by cytokine storms.[4] Symptoms in 1918 were so unusual that initially influenza was misdiagnosed as dengue, cholera, or typhoid. One observer wrote, "One of the most striking of the complications was hemorrhage from mucous membranes, especially from the nose, stomach, and intestine. Bleeding from the ears and petechial hemorrhages in the skin also occurred".[46] The majority of deaths were from bacterial pneumonia,[66][67] a common secondary infection associated with influenza. The virus also killed people directly, by causing massive hemorrhages and edema in the lung.[67]