A total of 50 samples were collected from keyboards (25 samples)and mice (25 samples)of multiple-user
computers used in the main internet center of Al-Mustansiriya University, Baghdad , Iraq.
A sterile normal saline moistened swabs were wiped firmly over the entire surface of the specific object. Each
swab was placed in 1 ml of brain heart infusion broth(Hi-Media / India) and incubated overnight at 37°C,
vortexed for one minute and serial ten-fold dilutions was made, 100 μl from the last dilution(10-6) was plated on
nutrient agar and incubated overnight at 37°C.Each colony was plated on blood agar, MacConkey agar ,eosin
methylene blue agar and mannitol salt agar(Hi-Media / India) then incubated aerobically at 37°C for 24 h. The
pure colonies of isolates were identified and characterized using standard microbiological techniques