The streaks are caused by condensation, which forms puddles, allowing the bacteria to diffuse. You should grow your agar plates upside-down to avoid them. Microbiologist here.
It could still be condensation clinging to the agar. He said he put the agar in a bag above a heater. Things probably got pretty steamy in there.
The only other explanation I can think of is that those bacteria are motile but I find it odd that they would all move "away" from the center of the keyboard.
Mouses, keyboards, laptops, mobile phones, pads, all belong on a table. As we used to read in paper format, during a meal, we now use them. Rather than removing them, instead make them easier to clean. Not that food is the only source of dirt and bacteria, they get extra dirty because we spend the most time in contact with them. I would love to wash my keyboard, mouse, and pad, in a sink.
You can wash a keyboard and mouse in a dishwasher. Lots of site out there describing that. Seen colleagues doing after a coffee spill. You just have to make sure the heat is off, and give them days to dry off.
Laptops are problematic because of batteries inside that are difficult to remove, and that we don't want to be deprived of our laptops for several days.
Lenovo Thinkpads have drain holes as part of the keyboard and chassis design. Liquids should travel straight through the machine. https://www.youtube.com/watch?v=d7cvi00OZDM
They don't warrant the machine will survive, but at least the design makes a good effort.
Fun fact: There are lots of bacteria in the environment that aren't culturable. Some are known species.[0] But there are also tens of thousands of uncharacterized bacterial species in soil.[1]
Wow, that's amazing. Is it possible to cultivate them at all, albeit at great expense and effort? Or is it entirely unfeasible? The Wikipedia article on "Viable But Not Culturable" is quite brief.
It's not feasible to culture them all. We don't know what kind of culture medium to use for every species. Some species of bacteria require other species of bacteria to grow. In other words, we don't know what we don't know about culturing a lot of bacteria. We know they're there based on DNA sequencing.
Have there ever been any examples where people have figured out how to culture them? e.g. figuring out an unusual medium and what other species they need. Or has it never been done?
When my wife was working on her Ph.D, there were only shared computers in her lab. After an upgrade, I re-purposed her old home desktop to be able to take care of the basics and sit at her desk -- it wouldn't handle everything, but would be useful for most of the day-to-day work.
Suddenly she got sick much less often. So, what I'd really love to see would be this project using a shared computer keyboard, and I'm not talking about the same family, for example. Of course, I'm not sure in this era of laptops that shared machines happen all that often anymore.
But aren't most common illnesses (e.g. cold and flu) from viruses, not bacteria? I wouldn't expect this sort of culture to show the kind of stuff that causes most people to get sick, even if it is spread by things like keyboards or mice or door handles.
I wouldn't worry too much. How many of those bacteria are completely harmless or even beneficial? (think skin flora)
That said, I recently cleaned the keyboard of a shared computer at work using ethanol because it was really gross. I also regularly vacuum the one I have at home.
I've learnt the jankiest keyboards belong to those who eat at their desk. Don't eat at your desk and your keyboard stays relatively clean and nice. Plus you're not putting that bacteria directly into your mouth.
While this isn't common any more, I used to work in an environment where people smoked at their desks... A smoker's keyboard can become a truly horrifying thing.
oh goodness… back the nineties I was in charge of an office network where some of the folks would smoke after hours.
The CPU fan in one of the 386 computers started to make this horrible sound, so I disassembled it and found the entire interior of thick with soot, I’m talking several inches of accumulated soot on every surface. It was like the computer was lined the the fur of a black rabbit.
anyway, as indicated elsewhere in this thread, I have had great success with running keyboards and mice through dishwashers.
Would be an interesting experiment to see what cleaner is most effective in removing that gunk, then mixing with water and a smoker "inhaling" it into their lungs.
Would it clean their lungs of similar gunk or would the water return clear as it went in?
Always thought people eating sandwiches, burgers, etc. with their hands while also typing is gross.
Keeping things clean, though: buy a box of 70% isopropyl pads (about 1"x1" squares) at your CVS/Walgreens and use them to clean your keyboard, mouse, door handle, kitchen counter, etc. Works great and leaves no residue. Don't use on wall paint and other alcohol-soluble surfaces.
Consider how many people look at their phone while on the toilet. They (hopefully) wash their hands afterward, but how many people regularly sanitize their screen? Consider that the next time someone hands you their phone to show you something.
Thank you for the encouragement. I went ahead and checked it out and you are right. Not bad at all. Boiled down to: do keyboards have bacteria? Answer: Yes. The whole-keyboard agar was an interesting approach.
The human eye can't see UV light, so I guess it is converted to visible light when used as a backlight. But here's an article about someone experimenting with a UV light to desinfect their keyboard: http://www.pcworld.com/article/237186/can_a_uv_light_kill_th... (lots of pictures of agar plates)
I was thinking the same think. My toothbrush (Phillips SonicCare) has a UV light in the compartment that holds the toothbrush heads. Would it be possible for keyboards to have something similar? (for the many that have LEDs, perhaps some sort of UV light that activates while keyboard is idle.. probably wouldn't kill all bacteria, but at least some, similar to toothbrush)
