[ WP ] The reason why Earth has so many varieties of diseases , parasites and bacteria is because countless alien civilizations use Earth as a testing ground for weapons and vaccines , and they did n't expect anything to live here . We find out eventually and get very angry .

`` What the hell, man?'' 
 
 `` We're really sorry about that.'' 
 
 `` Seriously? You did n't check first?'' 
 
 `` Again, we're really sorry about that.'' 
 
 `` Because... we've been down here for awhile and diseases are really, just, everywhere.'' 
 
 `` Clearly an administrative oversight.'' 
 
 `` The plague was you?'' 
 
 `` Which plague?'' 
 
 `` THE PLAGUE.'' 
 
 `` Oh yes. That. We were quite proud of that.'' 
 
 `` Well it killed a whole lot of us.'' 
 
 `` That's what it was supposed to do.'' 
 
 `` Really?'' 
 
 `` We apologize again, we just worked really hard on that one.'' 
 
 `` And HIV, was that you too?'' 
 
 `` Oh yes.'' 
 
 `` What is wrong with you?'' 
 
 `` Well strictly speaking that was n't an actual bio-weapon, Jenkins just had a bit too much fun on vacation and contaminated a sample. We cured that decades ago'' 
 
 `` Dude... not okay.'' 
 
 `` Jenkins apologized to you already.'' 
 
 `` Well that's not enough!'' 
 
 `` I really do n't know what more you want. Clearly everything worked out for your species.'' 
 
 `` It would have worked a lot better without smallpox!'' 
 
 `` I'm sorry, small what?'' 
 
 `` Smallpox. You gave us smallpox. One of the worst, it killed millions. Many of us are still carriers.'' 
 
 ``... has anyone else ever heard of this one? Forlax? Jenkins?... anybody? Because he has n't been through decontamination... Nothing?'' 
 
 Shit
