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Name: Peter M.
Status: Student
Age: 16
Location: N/A
Country: N/A
Date: N/A 

What is the normal amount of single strand of bacteria on the human hand at any given time. How about the total amount of bacteria on the human hand?

THe only data I could find was from a study where the efficacy of hand washing for nurses in an intensive care unit was studied. The unwashed hands contained an average of 84 colony forming units (the classical unit with which we count viable micro organisms) per hand. The method applied was to determine the amounts of organisms on the fingertip so I guess this number should be corrected for the complete surface of the hand. In 30% of people there were more than 200 CFU present. You should bear in mind that nurses wash their hands pretty often anyway. Your hands after working in the garden, or cleaning the dustbin, would probably contain a factor 10 or maybe 100 more organisms. Wet or moist hands release more organisms than dry hands. The moist factor in part explains why washed hands (even washed with soap) often show up with a heavier bacterial load than unwashed hands. But I couldn't find exact numbers on this.

Trudy Wassenaar

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