|MadSci Network: Microbiology|
To determine what types of bacteria may be found on computer keyboards and phone receivers we should think about possible carrier sources. Bacteria could be suspended in the air or on airborne dust particles and eventually settle onto a computer keyboard or phone console. Human contact with computer keyboards may also result in bacteria inoculation. Normal microbial flora residing on our skin may be transferred to the computer keyboard. What types of bacteria can be found suspended in the air or inhabiting our skin? Some general characteristics include a resistance to drying (also known as resistance to desiccation). There is very little water available for bacteria suspended in the air or residing on a keyboard so these bacteria must be able to efficiently keep water in the cell otherwise they will dry out and die. Bacteria which are capable of this are better suited to the dry environments of the skin and inanimate objects. Examples include, Micrococcus, Staphyloccocus, and Corynebacteria. For additional information regarding bacteria living on our skin try the MadSci Normal Flora FAQ
Overall, the numbers of bacteria found on inanimate objects will be relatively low since there is no easily obtained food source and water availability is low. Bacteria found on these objects are transitory; either they will be transferred to a more suitable growth environment via our touch or they will remain dormant on the keyboard until their eventual death. Since we can pick up bacteria from inanimate objects it is probably wise to wash our hands periodically during the day and also to avoid touching our nose or eyes as this is a way to transmit bacteria from our skin to areas where growth can be more favourable. It should be noted that the microflora of our skin is relatively static as organisms that may be transferred to our skin can not out compete our normal flora for growth.
Hope this helps.
Try the links in the MadSci Library for more information on Microbiology.