Infectious Disease

 Let's collect some bacteria from our environment!

We will be using agar plates for this experiment as they can represent 'perfect' conditions for microbial growth.

Roll a clean cotton swab in your mouth or test something even more gross, like the keys on a computer, a mobile phone case, the pump handle of a soap dispenser or the remote control. Remember, you must use clean cotton swabs for each sample. In order to get a good sample, lightly dampen the cotton swab with water. Be sure to roll the swab on the surface you’re testing so that it’s completely covered and has picked up as much bacteria as possible. You want to cover the entire cotton end of the swab with invisible bacteria. 

Lift the lid off the petri dish and lightly draw a squiggly line in the agar with the end of the cotton swab. Roll the swab with your fingers as you draw the line gently across the agar. Replace the lid and label the dish with the date and the name of the item you tested. Pop them gently in the incubator at 37 degrees and leave them for a few days. 

Come back and check to see what bacteria share your space!

SUGGESTION: Place no more than a drop of a hand sanitizing gel in the middle of one of the squiggles. The hypothesis is that the antibacterial chemical in hand sanitizer will keep bacteria from growing there.

REMEMBER: Do not open the dishes once things begin to grow. You could be culturing some serious bacteria and not even know it. The comfort is that they were around you all the time anyway and now you can see them.