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E-nose Sniffs Out Nasty Resistant Bacteria
geekroot's dad writes "There have been several tries for an Electronic nose that seek out various airborne elements - they can find cancer, monitor recycled air for NASA and
find nasty bacteria better than lab tests. Now as methicillin-resistant Staphylococcus aureus (MSRA) becomes a problem not only in hospitals but in everyday life some British scientist have built a super nose to find the 'little buggers'."
Imagine the applications in everyday cubicle's life: A smell map of the office to answer the eternal question: The more you smell, the better you code ?
This sort of thing lends itself to non-intrusive search and what civil libertarians call "violation of privacy."
A similar technique is looking at heat, and using it to identify folks growing things in their houses: fly over with a helicopter looking at heat signatures -- the growers' houses light up. The court had to decide if this was an illegal search or not.
Already there have been cases where cops had drug dogs sniff folks on a bus and identify smugglers. The court had to decide if the cop searched people (illegally) just by walking by them with a dog, or if the cop was innocently walking by folks, and when his dog aletered, the cop became the probable cause to search further.
Electronic noses, with their reduced cost and targeted nature, will lead to many similar cases. A cop's e-nose might alert. He'd followup with a search, find contraband and so on. The question is, was it OK for him to have an e-nose sniffing in the first place? Or did he need a search warrant to use the e-nose?
One can imagine an e-nose built to sniff explosives, but that also sniffs out everything else. In that case, the cops have a legit purpose to search (national security), but the effect is that they'll be busting folks for all sorts of other violations.
http://www.thebricktestament.com/the_law/when_to_
Staph bacteria is something that's very common on the outside of people. The article itself places the number at 30%, and that number is much higher for kids who handle unsanitary things all the time don't wash their hands as often as they should. It's not an epidemic because it has to enter your blood through an open wound. Most adults simply don't cut themselves very often (with the exception of shaving, but that's sanitized anyhow), so the majority of staph infections are in kids.
The problem with this device is when would you use it? Either you're waiting for mom to bring in the kid after you already think she has a staff infection, or you're sniffing everyone at random. If mom thinks it's a staff infection, the kid probably does have staph bacteria on him, but that doesn't get you any closer to knowing if that's the infection. If you're sniffing everyone at random, you're really only picking out the people that don't wash their hands enough and making them pay for it with extra (almost certainly unnecessary) testing.
In either case, who's celebrating this as some kind of new breakthrough that's going to revolutionize the health care industry? This really makes me wonder if this device is more for revenue than for health screening. "Hey, it looks like you tested positive for a possible staff infection. I'm sure your insurance will cover some extra tests."
Years ago one of my med school teachers taught us to sniff wounds for infection. He said that with a bit of practice you could quickly learn to discriminate infections and it's true.
Even now I often sniff dressings for infection and I'm right most of the time. The odour of different infections are quite characteristic and you can easily tell if it's light or heavy.
Gets some funny looks at times, but I can usually beat the labs by 24 hours. My students think I'm a bit odd, but I notice that now they too take a surreptitious sniff and then pronouce wisely!
Long live the Mark I nose.....
The current theories on the cause of antibiotic resistant bacteria place the blame on antibiotics and their overuse or under use. These theories utterly fail to explain one simple fact: most people don't come into the hospital with cases of drug resistant bacteria, they acquire those infections while in the hospitals. Some where in the hospital there are conditions which are breeding drug resistant bacteria.
I believe that the real cause of antibiotic resistant bacteria is far more prosaic than anyone has suspected. Before Doctors and Nurses give people injections they are quite properly taught to point the needle up, tap the syringe to force air bubbles to the top of the syringe, then squirt enough of the fluid out of the syringe to insure that the air is cleared from the device and the needle. This is utterly necessary to prevent the injection of air into the patient's blood system where it could cause a fatal embolism.
The antibiotic squirted out of the needle simply falls to the floor and creates a splatter. This splatter kills bacteria on the floor where it is intense enough to do so, but around the edges of the splatter surviving bacteria can breed resistant strains to every type of injectable antibiotic being used in the hospital.
When antibiotic splatter is combined with the modern janitorial practice of a one step floor cleaner, the floor becomes a giant Petri dish for the breeding of drug resistant bacteria. One step floor 'cleaners' can't possibly clean floors; they make the floor look clean and shiny, but since many of them are made of glycerin compounds they simply serve as a growth medium for the Petri dish.
So how do you solve the problem of antibiotic resistant strains of bacteria? You do two things: first, keep splatters of antibiotics off of the floor by performing the air clearing of the syringes while the needle is still in the bottle of antibiotics - immediately after filling the syringe- and by using a spillage overflow catcher pan under the syringe while it is being filled. Second, sterilize the hospital floors with bleach and intense ultra violet light sources mounted on the undersides of push broom like devices.
These two simple things will prevent the Petri dish conditions on floors which breed drug resistant bacteria. Both of these steps have very low costs while having very large benefits. They are similar in importance to the now standard practice of surgeons washing their hands before surgery, which was adapted in the 19th century, and which has saved countless lives since.
The economic justification for all of these things is obvious, reducing drug resistant bacteria cases will save insurance companies far more money than the slightly greater costs of better floor cleaning and splatter prevention protocols would cost them.