Seattle policemen wearing cloth face masks handed out by the American Red Cross during the Spanish flu pandemic, December 1918
This image represents the public health response and protective measures taken during the pandemic
Spanish flu
Timeline of the 1918-1920 Spanish flu pandemic, the deadliest pandemic in history that infected one-third of the world's population and killed an estimated 17-100 million people across four waves.
1918 CE - 1919 CE
First documented cases in Haskell County, Kansas
The earliest documented cases of what would become the Spanish flu pandemic appeared in Haskell County, Kansas. Local doctor Loring Miner observed the disease and warned the U.S. Public Health Service. This rural outbreak would later spread to military camps and around the world.
Treaty of Brest-Litovsk spreads flu to Russia
After the signing of the Treaty of Brest-Litovsk in March 1918, Germany started releasing Russian prisoners of war, who brought the disease back to their country, facilitating the pandemic's spread to Russia.
Albert Gitchell case at Camp Funston marks pandemic beginning
The pandemic is conventionally marked as beginning with the recording of Albert Gitchell, an army cook at Camp Funston in Kansas. Within days, 522 men at the camp had reported sick, demonstrating the rapid spread in military facilities.
Virus reaches Queens, New York
By March 11, 1918, the influenza virus had spread from the military camps to reach Queens, New York, marking its arrival in major population centers on the East Coast.
Pandemic reaches Western Front and Europe
The flu became epidemic in the Midwest, East Coast, and French ports by April 1918, reaching the Western Front by mid-April. It then quickly spread to France, Great Britain, Italy, and Spain, severely impacting World War I military operations.
Pandemic reaches Asia and global spread
The flu reached North Africa, India, and Japan in May 1918, and soon after had likely gone around the world with recorded cases in Southeast Asia in April. This marked the truly global nature of the pandemic.
First Spanish newspaper reports appear
On May 21, 1918, El Liberal published likely the first account in Spain of the Spanish flu, titled 'Can One Live? The Fashionable Illness.' Spanish newspapers freely reported the outbreak due to wartime neutrality, leading to the 'Spanish flu' misnomer.
El Sol (Madrid), 28 May 1918: "The three-day fever – In Madrid 80,000 Are Infected – H.M. the King is sick"
Spanish newspaper coverage of the flu outbreak
The Times reports 'Spanish influenza' name
The Times of London reported that 'Everybody thinks of it as the Spanish influenza to-day,' marking the widespread adoption of the misleading name that would stick throughout history despite Spain not being the origin.
Front page of The Times (London), 25 June 1918: "The Spanish Influenza"
British newspaper coverage establishing the 'Spanish flu' name
Pandemic reaches Australia, first wave ends
After reaching Australia in July 1918, the first wave of the pandemic started to recede. This first wave was relatively mild with mortality rates not appreciably above normal, but it disrupted military operations significantly.
Deadly second wave begins
The second wave began in the second half of August 1918, probably spreading to Boston, Massachusetts and Freetown, Sierra Leone. This wave was much more deadly than the first, with October 1918 becoming the month with the highest fatality rate of the entire pandemic.
American Expeditionary Force flu patients at U.S. Army Camp Hospital no. 45 in Aix-les-Bains, France, 1918
Military hospital treating flu patients during the deadly second wave
New York City's first influenza fatality
On September 15, 1918, New York City saw its first fatality from influenza during the deadly second wave, marking the pandemic's lethal arrival in America's largest city.
Philadelphia Liberty Loans Parade disaster
The Philadelphia Liberty Loans Parade held on September 28, 1918, to promote government bonds for World War I, resulted in a massive outbreak causing 12,000 deaths. This became one of the most tragic examples of how public gatherings accelerated the pandemic's spread.
Peak mortality month of October 1918
October 1918 was the month with the highest fatality rate of the whole pandemic. In the United States alone, approximately 292,000 deaths were reported between September-December 1918, compared to only 26,000 during the same period in 1915.
Armistice celebrations cause new outbreaks
The celebrations of the Armistice of November 11, 1918, caused outbreaks in Lima and Nairobi, demonstrating how public gatherings continued to spread the disease even as the war ended.
Second wave mostly ends by December
By December 1918, the deadly second wave was mostly over, but the pandemic had already caused unprecedented mortality worldwide, fundamentally changing public health approaches and leaving lasting impacts on global society.
Seattle policemen wearing cloth face masks handed out by the American Red Cross during the Spanish flu pandemic, December 1918
Public health measures during the pandemic's peak
Third wave begins in 1919
Pandemic activity persisted into 1919 in many places. Cases began to rise again in some parts of the U.S. as early as late November 1918, with significant outbreaks occurring in cities including Los Angeles, New York City, Memphis, Nashville, San Francisco, and St. Louis.
London weekly deaths from influenza during 1918 and 1919
Statistical record showing the three waves of the pandemic
Australia experiences first outbreak
Influenza entered Australia for the first time in January 1919 after a strict maritime quarantine had successfully shielded the country through 1918. It assumed epidemic proportions first in Melbourne, peaking in mid-February.
European third wave peaks
A significant third wave developed in England and Wales by mid-February 1919, peaking in early March. France also experienced a significant wave that peaked in February, alongside the Netherlands, demonstrating the pandemic's continued global impact.
Fourth wave begins in Japan
In Japan, the flu broke out again in December 1919 and spread rapidly throughout the country. Between October 1919 and January 23, 1920, 780,000 cases were reported across the country, with at least 20,000 deaths recorded.
Japanese women in Tokyo during the Spanish flu pandemic, 1920
Japanese public health response during the fourth wave
1920 CE - 1921 CE
Chicago outbreak begins fourth wave in US
Chicago experienced one of the first major outbreaks of the fourth wave beginning in mid-January 1920. The disease spread at an even faster rate than in winter 1919, though fewer were dying. The outbreak quickly spread outward from the center of the country.
American Red Cross nurses tend to flu patients in temporary wards set up inside the Oakland Municipal Auditorium
Medical response during the pandemic's later waves
Fourth wave peaks and subsides
The fourth wave in the United States reached a peak in early February 1920 and subsided as swiftly as it had appeared. According to data, this epidemic resulted in one third as many deaths as the 1918-1919 experience, but still caused significant mortality.
Pandemic declared largely over
By mid-1920, the pandemic was largely considered to be 'over' by the public as well as governments. Though parts of Chile experienced a third, milder wave between November 1920 and March 1921, the flu seemed mostly absent through the winter of 1920-1921.
Seasonal influenza returns
Seasonal influenza began to be reported again from many places in 1921. The winter of 1921-1922 was the first major reappearance of seasonal influenza in the Northern Hemisphere, marking the transition from pandemic to endemic flu.
1922 CE - 1922 CE
Major seasonal flu outbreak in Northern Hemisphere
The winter of 1921-1922 saw the first major reappearance of seasonal influenza in the Northern Hemisphere since the main pandemic. Northwestern Europe was particularly affected, with all-cause mortality in the Netherlands approximately doubling in January 1922 alone.
