How long did the Spanish Flu last?

Here, I'll try to put an answer up that will give the situation we are faced with some perspective for the readers that hit this site.

Pandemics, like the "1918 Spanish Flu" was deadly to some extent for over 10 years.  The strain of influenza virus that is commonly referred to as the 1918 strain underwent several mutations, the most deadly beginning in March of 1918 and ending by the Spring of 1919.  The "1918 Influenza" was around in a less virilent form long before March of 1918.  Only when it began killing hudreds and then thousand and then tens of thousand of people per day did it become recognized as a pandemic and the moniker "Spanish Flu" get attached to it and become part of the language.

It was possible, mind you that this flucuation from unknown to deadly to less deadly to virtually non-existant progression noted historically with the "1918 Spanish Flu" may not apply to any new influenze virus that creates a pandemic.  It was possible that the 1918 version could have ebbed and flowed several times, in otherwords mutating into forms that were at first deadly, then lesser, and then back and forth between to two.  It could have lasted 30 years.  There just isn't any way to say "All Clear!!!" or state professionally that the coming pandemic is only going to last a year or two and only have three "waves" such as was seen in the 1918 version of an H5N1 virus that made the mutation which went H2H.

And, it's possible that any immunity that a person developes by exposure and survival of the first wave isn't going to have any real protection against a second or third or sixth wave because the virus can mutate to such an extent that any immunity developed from in the intial exposures is obsolete due to the extent of any new mutation further on down the line.

That probably wasn't really helpful in helping anyone that is doing preps for this situation, but it is a realistic assessment, and my best answer to the first post in this thread.