
As the US had entered World War I, the disease quickly spread from Camp Funston, a major training ground for troops of the American Expeditionary Forces, to other US Army camps and Europe, becoming an epidemic in the Midwest, East Coast, and French ports by April 1918, and reaching the Western Front by the middle of the month. It then quickly spread to the rest of France, Great Britain, Italy, and Spain and in May reached Breslau and Odessa. After the signing of the Treaty of Brest-Litovsk (March 1918), Germany started releasing Russian prisoners of war, who then brought the disease to their country. It reached North Africa, India, and Japan in May, and soon after had likely gone around the world as there had been recorded cases in Southeast Asia in April. In June an outbreak was reported in China. After reaching Australia in July, the wave started to recede.