How long did the spanish flu last - Why the 1918 Flu Pandemic Never Really Ended

The earliest documented case was March 1918 in , United States, with further cases recorded in France, Germany and the United Kingdom in April.

These outbreaks probably lessened the significance of the influenza pandemic for the public.

The lower estimates of the Chinese death toll are based on the low mortality rates that were found in Chinese port cities for example, Hong Kong and on the assumption that poor communications prevented the flu from penetrating the interior of China.

Poland experienced a devastating outbreak during the winter months, with its capital Warsaw reaching a peak of 158 deaths in a single week, compared to the peak of 92 reached in December 1918; however, the 1920 epidemic passed in a matter of weeks, while the 1918—1919 wave had developed over the entire second half of 1918.