Brief outline of the history of world epidemics-­­pandemics. Part III. The half forgotten viral debut

A little more than a hundred years ago, the humanity plunged into the second wave of «the Spanish flu» just like in the spring of 2021 it plunged into the second wave of coronavirus. Despite the significant biological and virological differences between COVID-19 coronavirus and the Spanish flu, already known to us in the second year of the pandemic, the obvious significant similarity in the dynamics of the epidemiological scenarios of both pandemics is striking.It is officially believed that the epidemic in Europe began in the last months of the deadly First World War (1914—1918). Its development and the next catastrophic spread were caused by: unsanitary conditions, poor nutrition, overcrowding in trenches and refugee camps, the demobilization and the return of soldiers home, as also the rapid development of vehicles at the beginning of the 20th century (trains, cars, high-speed ships). The Spanish flu, caused by the H1N1 virus, had several «waves». It is difficult to estimate the exact number of those who had the Spanish flu, but presumably, this is 500—550 million people. About 25 million people died (some studies indicate a figure of 50 or even 100 million). Unfortunately, the mankind quickly forgot about this viral pandemic and consequently was objectively compelled, after a hundred years, to unexpectedly make the same mistake again and introduce quarantine as the only way to limit the further spread of the next viral pandemic of mankind. The Spanish flu significantly influenced all the further development of medicine. While before the deadly pandemic the private medical practice was widespread, in the process of its overcoming, the formation of the modern international health care system took place. In 1919, the International Bureau for Epidemic Control was founded in Vienna.