根据以下材料，回答

There are two types of people in thisworld: those who regularly wash their office coffee cup. And those who only takeit off their desk to cover up the coffee mark at the bottom with a fresh pour, drivingaway their shame with the reasoning that the heat must kill the bacteria orspine thing.

Depending on which type of person you are,this will be either mildly annoying or more-than-mildly exciting. As HeidiMitchell wrote in a recent Wall Street Journal column, it′ s fine to never washyour cup, as long as you′ re not sharing it with anybody else.

There are two warnings to that statement,infectious-disease expert Jeffrey Strake, a professor at Baylor College ofMedicine, told Mitchell; One, it only applies if you′re not sharing the cupwith anybody else. And two, if you leave cream or sugar in your cup over theweekend, that can certainly cause mold(霉) to grow--in which case, wash it out.

Otherwise, though, there′s not really muchto worry about. "If I went and cultured the average unwashed coffee cup,of course I would find bacteria." Starke said. "But remember the vastmajority came from the person who used the cup." Even if you drink from itwhile sick, it′s pretty hard to re-infect yourself with the same cup; mostviruses don′t live long outside the body, which means that just letting yourcup live in its own dirt may be a safer bet than the alternative; cleaning it withthe disgusting sponge (海绵) in theoffice kitchen "The sponge in the break room probably has the highestbacteria count of anything in the office." Starke said if the idea of notwashing horrifies you, just stick the sponge in the microwave before using.Otherwise, though, reel free to continue your lazy ways without guilt.

What does the passage intend totell us?