WI Spanish Flu hit in 1913

I have no doubt this has already been suggested some time ago, but, what if the spanish flu, which killed 5% of the world population in 1918, hit before, and not after the first world war?

It wouldn't have spread as fast or as far. The large movements of people bbecause of the war allowed the flu to spread wider and faster than it would have otherwise

It should be less severe. Better sanitation outside of war. Less hunger. Fewer people moving.

Now if you are asking what happens if 5% of the population dies in 1913 to disease, concentrated among the people under 40, then it has a lot of effects.

- Like any great shock in 1913, likely butterflies away WW1. Does butterfly away WW1 as we know it, since a loss of up to 10% of your combat aged men has big impacts.

- Likely cause weaker governments to fall. Any government that change power or came close to change who was in power will have a tough time staying in power.

- Likely lose important heads of state or their wives. Which ones will matter a lot. For example the Tsar or the Tsars wife dying would be a huge event.

- We get an interruption/lessening of immigration from Europe to rest of world. For example, in Congress of Poland, the farms were down to legal minimum of 8.5 acres per man, so everyone who is not first son or his wife has to find new jobs. Many would leave Poland to places like the Ruhr factories or USA. With 5-10% of farms now empty, you will see many of these people not leave homeland or not move to Polish Urban centers.

You could get a lot more detail, but you have to sketch out a TL about where the disease hit hardest. Death %, and the like. And who dies does matter. Say lets assume a WW1 starts of anyway, if Churchill died to the flu the year before, the we could see some radically different choice for the UK.

To begin with, it would be known as the American Flu, as patient 0 was in Kansas, and without the massive troop movements caused by the war, its effect would probably be contained into the American mainland.