Syndemic
The worst of the 20th century influenza pandemics was the 1918 pandemic, where between 20-40 percent of the world’s population became ill between 40-100 million people died. More people died of the so-called Spanish flu (caused by the H1N1 viral strain) pandemic in the single year of 1918 than during all four-years of the Black Death. The pandemic had devastating effects as disease spread along trade and shipping routes and other corridors of human movement until it had circled the globe. InIndia, the mortality rate reached 50 per 1,000 population. Arriving during the closing phase of the World War I, the pandemic impacted mobilized national armies. Half of U.S. soldiers who died in the "Great War," for example, were victims of influenza. It is estimated that almost ¾ of a million Americans died during the pandemic. In part, the death toll during the pandemic was caused by viral pneumonia characterized by extensive bleeding in the lungs resulting in suffocation. Many victims died within 48 hours of the appearance of the first symptom. It was not uncommon for people who appeared to be quite healthy in the morning to have died by sunset. Among those who survived the first several days, however, many died of secondary bacterial pneumonia. It has been argued that countless numbers of those who expired quickly from the disease were co-infected with tuberculosis, which would explain the notable plummet in TB cases after 1918.
Horses in World War I
The continued resupply of horses was a major issue of the war. One estimate puts the number of horses that served in World War I at around six million, with a large percentage of them dying due to war-related causes. In 1914, the year the war began, the British Army owned only about 25,000 horses. This shortfall required the US to help with remount efforts, even before it had formally entered the war. Between 1914 and 1918, the US sent almost one million horses overseas, and another 182,000 were taken overseas with American troops. This deployment seriously depleted the country's equine population. Only 200 returned to the US, and 60,000 were killed outright. By the middle of 1917, Britain had procured 591,000 horses and 213,000 mules, as well as almost 60,000 camels and oxen. Britain's Remount Department spent £67.5 million on purchasing, training and delivering horses and mules to the front. The British Remount Department became a major multinational business and a leading player in the international horse trade, through supplying horses to not only the British Army but also to Canada, Belgium, Australia, New Zealand, Portugal, and even a few to the US. Shipping horses between the US and Europe was both costly and dangerous; American Expeditionary Force officials calculated that almost seven times as much room was needed per ton for animals than for average wartime cargo, and over 6,500 horses and mules were drowned or killed by shell fire on Allied ships attacked by the Germans. In turn, New Zealand lost around 3 percent of the nearly 10,000 horses shipped to the front during the war.