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.
World War II casualties
Included with total war dead are victims of Japanese war crimes.The total war dead in the USSR includes about 1 million victims of Stalin's regime. The number of deaths in the Gulag labor camps increased as a result of wartime overcrowding and food shortages. The Stalin regime deported the entire populations of ethnic minorities considered to be potentially disloyal. Since 1990 Russian scholars have been given access to the Soviet-era archives and have published data on the numbers of people executed and those who died in Gulag labor camps and prisons. The Russian scholar Viktor Zemskov puts the death toll from 1941–1945 at about 1 million based on data from the Soviet archives. The Soviet-era archive figures on the Gulag labor camps has been the subject of a vigorous academic debate outside Russia since their publication in 1991. J. Arch Getty and Stephen G. Wheatcroft maintain that Soviet-era figures more accurately detail the victims of the Gulag labor camp system in the Stalin era. Robert Conquest and Steven Rosefielde have disputed the accuracy of the data from the Soviet archives, maintaining that the demographic data and testimonials by survivors of the Gulag labor camps indicate a higher death toll. Rosefielde posits that the release of the Soviet Archive figures is disinformation generated by the modern KGB. Rosefielde maintains that the data from the Soviet archives is incomplete; for example, he pointed out that the figures do not include the 22,000 victims of the Katyn massacre. Rosefielde's demographic analysis puts the number of excess deaths due to Soviet repression at 2,183,000 in 1939–40 and 5,458,000 from 1941–1945. Michael Haynes and Rumy Husun accept the figures from the Soviet archives as being an accurate tally of Stalin's victims, they maintain that the demographic data depicts an underdeveloped Soviet economy and the losses in World War Two rather than indicating a higher death toll in the Gulag labor camps.