tumblr-itus 

being so addicted to tumbr that you can't stop and your social life goes down the drain.

Annie: OH MY...i think i have tumblr-itus
Casey: WTF
Annie: you know...im not going out anymore, my hands are glued to the mouse pad...i can't stop making jokes only people with a tumblr can understand...plus i keep writing this: "la;ksjlkj" and correcting people when they write "your" when they mean "you're"
Casey: and when does this disease end?
Annie: never c:

tumblr-itus by anniekinns.tumblr.com June 21, 2011

Tumblritis 

The effect Tumblr has on its "bloggers". Slowly they become more and more hipster, eventually reblogging meaningless photos of images of Harry Potter defeating a sparkling Edward Cullen or cats sleeping peacefully.

This disease is nearly almost fatal, turning even the most normal adolescent into a Twilight-hating, hipster-esque, online-shopping, self-important asshole.
The only hope is an intervention before it's too late.

Jane: What happened to Beth? She used to hang out with us all the time.
Terry: Well, she got a Tumblr...
Jane: You don't mean-
Terry: Yes. Tumblritis.
Jane: Shit. Now she's going start wearing those stupid hats they don't stay on your head right and those fake glasses.
Terry: She already tried to convince me that Stephenie Meyer is a she-devil trying to steal J.K. Rowling's fire, who is apparently some type of Messiah.
Jane: Fucking Tumblritis. It ruins people.
Terry: It sure does.

Tumblritis by messie.egghead December 15, 2010

Tumblritis 

Inflammation of self to Tumblr. Can't-get-enough-of-tumblr disease.

Dude, I didn't get to class because of Tumblritis.

Tumblritis by kissables March 13, 2010