Unwashed and Washed Hand Prints
With the emergence of antibiotic resistance bacteria and discoveries of new and emerging viral diseases the importance of hand washing has become increasingly more important in disease prevention.
Bacterial handprints done durning the summer in a Stem Class. The unwashed hands, washed with soap and water, showed environmental contamination of both bacterial and yeast. Hand prints were done using large TSA Kirby Bauer plates. Plates were incubated at 37 degree's C for 24 hrs then 48 hrs at room temperature and finally held at refrigerated temperatures for a week or longer.
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhRXytX4MkVd9MVU1XNQo8jx1__a0vgbcuYbHhzBWqY5VDm9rxfO_rbXtUwLnTuReI-Xt5uJA4nRQHOLMDhDquNRT1Nm-iDCt18HLxB6X5BRdBDMELgTahtjesibLj6vvEsqRsTQMhrlCg/s640/IMG_6439.JPG)
Enlarged view of same hand after hand washing. Notice that the hand print has fewer Bacillus spp and compared to the unwashed hand print.
Colorful mix of yeast (yellow) or Micrococcus (smaller colonies), Staphylococcus (white) and various shades of orange (bright orange being Rhodutrula) on this finger print. Note: the large yellow colonies continue to grow at refrigerated temperatures.
As can be seen by both sets of unwashed and washed bacterial hand prints environmental bacteria and yeast are reduced in the washed print. The washed print mainly has normal body flora (Staphylococcus spp) with a few colonies of yeast and or Bacillus spp. The physical act of scrubbing seems to be removing the environmental bacteria/yeast, especially Bacillus, as well as dead skin. What is left in a washed hand is exposed bacteria normally found on the exposed skin.
Tee Shirt available at Cabrillo College Book Store(831479-6209
or
Niles Biological: http://www.nilesbio.com/cat499.html
All images copyright Sturm.
Unwashed and Washed Hand Prints
With the emergence of antibiotic resistance bacteria and discoveries of new and emerging viral diseases the importance of hand washing has become increasingly more important in disease prevention.
Bacterial handprints done durning the summer in a Stem Class. The unwashed hands, washed with soap and water, showed environmental contamination of both bacterial and yeast. Hand prints were done using large TSA Kirby Bauer plates. Plates were incubated at 37 degree's C for 24 hrs then 48 hrs at room temperature and finally held at refrigerated temperatures for a week or longer.
Bacterial handprints done durning the summer in a Stem Class. The unwashed hands, washed with soap and water, showed environmental contamination of both bacterial and yeast. Hand prints were done using large TSA Kirby Bauer plates. Plates were incubated at 37 degree's C for 24 hrs then 48 hrs at room temperature and finally held at refrigerated temperatures for a week or longer.
Enlarged view of same hand after hand washing. Notice that the hand print has fewer Bacillus spp and compared to the unwashed hand print. |
Colorful mix of yeast (yellow) or Micrococcus (smaller colonies), Staphylococcus (white) and various shades of orange (bright orange being Rhodutrula) on this finger print. Note: the large yellow colonies continue to grow at refrigerated temperatures.
As can be seen by both sets of unwashed and washed bacterial hand prints environmental bacteria and yeast are reduced in the washed print. The washed print mainly has normal body flora (Staphylococcus spp) with a few colonies of yeast and or Bacillus spp. The physical act of scrubbing seems to be removing the environmental bacteria/yeast, especially Bacillus, as well as dead skin. What is left in a washed hand is exposed bacteria normally found on the exposed skin.
Tee Shirt available at Cabrillo College Book Store(831479-6209
or
Niles Biological: http://www.nilesbio.com/cat499.html
All images copyright Sturm.
Dear Tasha
ReplyDeleteI want to contact you with regards to these photo's, to use them in a publication, but I can't seem to find any contact information. Could you please contact me at joke.soetewey@plantyn.com?
Kind regards
Joke