In fact, the Legacy rules themselves suggest playing a few games if you aren't familiar with Pandemic.
IF YOU'VE NEVER PLAYED PANDEMIC...
We recommend that you play a few games without any of the special"Legacy
" rules to get a feel for the decisions you will have to make.
Read this rulebook then play without using the following rules: •Game Months, Legacy Deck, Dossiers •Objectives, Funding, Game Calendar, Panic Level •Scars and Lost Characters •Game
End Upgrades
The object of these warm-up games is to cure four diseases before any ofthe game-losing conditions are triggered (noted on page 14 of these rules).You should play at least two games this way to get a feel for the game beforeadding the additional rules.
boardgames.stackexchange.com/users/14341/Joe
Yes, you could play something very similar to vanilla Pandemic using just the base game components and ignoring all the Legacy elements.
The board is slightly different, but you probably won't even notice.
You can really only do this before you start playing the legacy version though.
Once you start playing the legacy version, things will happen that will modify the game in ways that will quickly make it difficult or impossible to play the base game.
boardgames.stackexchange.com/users/178/bwarner
Thats not true.
You can play the game even after you finish the legacy version.
Simply take out all the stickers that got put on during legacy play.
They r really easy to take off.
boardgames.stackexchange.com/users/14288/Abba
Yes, you can play “vanilla” before, during and after playing the campaign.
During the campaign: don’t destroy anything, just put it aside 1 before placement, shift stickers a little so that they don’t hide information of the virgin board 2 During the “vanilla” play: follow vanilla rules according to the Legacy rule book (or download and read vanilla rules) ignore stickers do not incorporate introduced Legacy material (easy to avoid) use all the 5 vanilla events only Resilient Population One Quiet Night Forecast Airlift word Government Grand word use the 5 available roles and find a way to shuffle them 4/7 from vanilla vrol Medic Scientist Researcher
Dispatcher 1/6 from On the Brink exp Generalist
You might want: find and print all the vanilla roles (only 5 in Legacy and not easy to shuffle)
use On the Brink
exp rules regarding event cards: use 2 cards per player draw form a pool of “funding”/event cards the 5 vanilla cards and 2/8 On the Brink cards available in Legacy 5
Borrowed Time Remote Treatment
the last Legacy card “flexible aid package” 4 could be used as well 6 use the original lines between cities, instead of the Legacy modifications there would be no connections between these yellow cities: Los Angeles – Lima Santiago – Buenos Aires Buenos Aires –
Johannesburg there would be connections with black/red: Bagdad – Karachi Chennai – Bangkok 1
actually, you can still destroy almost all material as instructed in legacy, just not the material you need in vanilla (and you will know which that is) 2
the majority of the stickers (e.g. panic level) do not even hide anything and the ones who might you can probably remember word
the card has different wording to accommodate Legacy features, but the effect is the same 4
I am not sure about the name, as the one I have is in German exp
On the Brink is the first expansion of vanilla Pandemic: among other things it includes Events and Roles which can be used for vanilla play 5 later in Legacy you will discover another event from On the Brink: New Assignment word 6
you will discover up to 5 other unusable event cards which could be re-purposed for events from vanilla expansions vrol the Quarantine Specialist (non-vanilla abilities only;
needs to be played with original features in mind) and the Operations Expert word come later, the Contingency Planner is not in Legacy
boardgames.stackexchange.com/users/10405/Robert Siemer
Like people said before, it is easy to play vanilla pandemic with the pandemic legacy box.
Moreover, various extra components/rules supplied with the game and gradually revealed through the game make it possible to play many interesting modifications of the game even after you finish the campaign.
boardgames.stackexchange.com/users/14469/stas g
I've never played Pandemic, but thinking of getting the Legacy edition. Is it possible to play it without the legacy elements a few times first, and get an experience that is same or similar to that of the regular Pandemic?
Can Pandemic Legacy be played as "vanilla" Pandemic?
boardgames.stackexchange.com
<pandemic><pandemic-legacy-season-1>
boardgames.stackexchange.com/questions/27269
boardgames.stackexchange.com/users/14088/Magician
Yes, you can just play without the Legacy elements. Read the rulebook then play without using certain sections. Yes, it is easy to play “vanilla” before, during and after playing the campaign by using just the base game components and ignoring all the Legacy elements.  During the “vanilla” play, follow vanilla rules according to the Legacy rule book, ignore stickers and do not incorporate introduced Legacy material, just use all the 5 vanilla events.  
S4: Read this rulebook then play without using the following rules:  •Game Months, Legacy Deck, Dossiers  •Objectives, Funding, Game Calendar, Panic Level  •Scars and Lost Characters  •Game Yes, it is easy to play “vanilla” before, during and after playing the campaign by using just the base game components and ignoring all the Legacy elements.   During the “vanilla” play, follow vanilla rules according to the Legacy rule book, ignore stickers and do not incorporate introduced Legacy material, just use all the 5 vanilla events.  