Shipperitis is a new disease that has already infected a countless number of X-Philes. It is highly contagious and NO cure has yet been found. Shippers (as this disease's victims are called) believe in and/or are devoted to a romantic relationship between Special Agent Fox Mulder and Special Agent Dana Scully. Everybody watching the X-Files (even if it is just one episode!) is in danger of contracting Shipperitis, but the risk of being infected multiplies if you have access to the Internet.
WARNING: If you  don't want to become a Shipper, do not watch the series or the movie and don't surf the Net! Otherwise it is highly probable that one day you will be one of the victims, and once you're a Shipper, it is nearly impossible to be cured.

On the other hand: what's so bad about being a Shipper?! If you are one (take the shipper-test to find out!),
 
 

enjoy it!