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Use of germicidal ultraviolet light to instantly, chealply, and efficacious disinfect hands of nurses, doctors and consumers world-wide

Proper Hand Hygiene practice is acknowledged as the key means, the cornerstone, to prevent hospital acquired infections and to protect consumers world-wide from infectious bacteria, virus, and spore. However, current hand hygiene technology cannot effectively deal with the widespread environmental contamination throughout hospitals, particularly on compromised soft and hard surfaces within patient rooms and intensive care units, as well in food prep areas, offices, airports, schools, and starbucks!Even when used as instructed, the most utilized current approach, alcohol based hand rubs (AHRB) technology, have well documented microbiology limitations
AHBR have limited ability to sanitize and fall considerably short of the nominal sanitation goal of 99.99 % inactivation, (-4 Log10 ) unless used vigilantly for 30 seconds with full coverage of the both bare hands.
ABHR demonstrate some effectiveness on vegetated bacteria
ABHR much less efficacious on virus and are completely ineffective on bacterial endospores such as C. difficile
ABHR are not effective at all on standard exam or surgical gloves, which also get compromised during patient care, emergency room care, in the OR, and in food service areas
When used as recommended by the CDC, disinfection once on the way into a room and once again on the way out of the room, there are well documented AHRB user limitations such as taking too much time and causing too much skin irritation over the course of an 8 hour shift
In addition, the CDC mode does no account for recontamination of hands during patient care so any benefit of hand disinfection is quickly lost
The WHO mode, which recommends multiple hand disinfections during the course of patient care, results in more benefits but exacerbates the limitations of AHBR even more
ABHTR are expensive on a per dose basis (>$0.07). The CDC mode costs USA hospitals close to $3 Billion per year in consumable supplies. The WHO mode would result in even more scosts to h

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    Sep 22 2013: I would like to know if this technology could be used similarly to a microwave to insure the safety of food before it is consumed?
  • Sep 11 2013: The problem with UV light is:
    1. It is light. You can't shine UV light into every nook and cranny of any object. Infectious agents can hide under those areas shielded by light.
    2. It is detrimental to certain plastics: UV light can weaken some plastics used in hospitals. Unfortunately plastic materials are very common in health care facilities. You might inadvertently destroy a piece of plastic that works to plug up something infectious from getting out.

    UV light has its uses... but with a wide limitations.
    • Sep 11 2013: Hi Jeff,

      Bingo. The current fad of applying UVC to room surface disinfection iafter a pateint is discharged s full of gaps and limitations. some of which you point out. There are many more. The marketeers of such systems are proferred band aids and fixes, but the whole premise is flawed. The key is to provide ongoing disinfeciotn of key touch surface DURING room occupancy. These will be explore more during the upcoming IUVA workshop and panel discusssion. One possible intervention duirng patient occupancy is
      the cornerstone of global infeciton prevention - proper hand disinfeciton. Since all surfaces are contaminated
      and the hands are the conveyor belt to transfer the pathogens from those surfaces to the susceptible patient.
      Current practice, even when done per instructions on the labels, and with the vigilance of the WHO recommendatrions falls well short of proper practice. UVC has the potential to fix this and has been shown to safely, efficacious, and less expensively enable Proper hand disinfection.
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    Sep 9 2013: UV light is already used for disinfection purposes in hospitals and it is most likely, for it to become even more popular, by the fact, that it does not create resistant bacterial cultures by the usual evolution process.

    Even though UV is highly effective and does not need long exposure times for surfaces to be sterilized, it is in its nature a light frequency which also effects human skin. For tanning purposes we have this light in the solarium to use the natural protection mechanism of increased pigmentation of our skin for our looks.

    As doctors and nurses would have to use this UV disinfection multiple times a day, it is most likely, that this could lead to an overexposure of their skin to this sort of light, and even though this would result in an increased pigmentation of their skin as for protective measures, it is most likely, that this protection may not be enough to prevent irreversible skin damage and finally lead to several forms of skin cancer. As with many carcinogens, it is a matter of exposure time and repetitiveness, which could exactly become the problem here.

    But I am just guessing and only combined the little knowledge I have, which should not keep you from refining and investigating this interesting idea.

    As for the 'the widespread environmental contamination' I am no fond of complete sterile surroundings, as I think our immune systems needs constant training and activation for it to work properly and to learn new 'intruders' as well as to constantly remember the already known ones.

    Hospitals are different, as they are not only a 'breeding chamber' for all sorts of germs by definition, but also that many people who are in them are actually lacking a full functional immune system. So our focus shout mainly be there where it is truly needed.
    • Sep 10 2013: For more information on the use of germicidal UVC in healthcare settings see IUVA event: UVC for infection prevention panel discussion. To be held on September 21st.

      UVC for bare and gloved disinfection has been demonstrated to be both safe and efficacious. Many exposure to UVC will not cause cancer - biophysically impossible - but it can induce erythema if the skin
      is not properly protected. That is an important part of the solution. UVA and UVB cause cancer. How is
      skin protected from these wavelengths in everyday life?

      UVC inactivation does not mutate, it renders pathgoens unable to reproduce. There is no chance of bacteria, virus, and spore becoming immune. UVC inactivation of infectious pathogens in hosptials (as well as in food processing plants and perfhaps everyday life )is important since infections can cause death and no doubt cost billions of dollars to remedy. Dangerous pathogens are just that, dangerous. Susceptibel patients, the elderly, and children can do perfectly well avoiding these germs.

      The key point - and why TED exists - is that innovation needs to be explained and fostered, and then commercialized and adopted to solve what before seemed like intractable problems. Hand Hygiene as
      currently practice in hospitals is problematic leading to an intractable problem, acquired infections. So innovation is necessary to solve this problem.

      Keep the questions coming and follow the event on social media sites.
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        Sep 10 2013: UV-C with its wavelength of 100–280 nm does not reach the surface of the earth as part of the natural sunlight, as it gets absorbed by the outer layers of the atmosphere already.

        Lacking this natural source, it isn't necessary, that our skin developed specific protective mechanisms against UV-C as well during evolution, and therefore should be investigated closely.

        According to wikipedia the UV-C band affects as follows:

        245 nm: Mainly Nucleic Acid disintegration, absorption minimum for Amino acid (proteins)

        253,7 nm: Used for bacteria and virus disintegration (disinfection)

        265 nm: Nucleic Acid disintegration (peak disintegration)
        280 nm: Amino Acid disintegration (maximum absorption of most proteins)

        As human DNA simply is a Nucleic Acid as well, why should it not be affected by disintegration as those of the DNA of bacteria and viruses?

        Even if the penetration depth of UV-C into the skin wasn't deep, which I don't know, it still would affect the outer skin-layer on DNA level, of which I also don't know how tolerable this is in quantity and intensity on human health. If those questions have already been investigated and found to be uncritical, than I wouldn't see any reason why it shouldn't be used for the named purpose.

        Especially because this method doesn't create resistance, at least as long as evolution doesn't come up with new concepts of UV-C blocker for bacteria and viruses ... :o)
  • Sep 9 2013: wouldn't the germicidal uv cause cancer? Doesn't the uv light for cleaning water changes the dna of the bacteria in the water?