Magic wand

Question

Dear ladies and gentlemen,
at a well-known and established mail order company I have seen a device, that is supposed to eradicate with allegedly 99,9% with UV-C light bacteria and germs from all surfaces. Allegedly with a high rate of success for Pseudmonas and MRSA. Could that be?
That would be a great idea for e.g. keyboards and handys, especially for people working in hospital....
Many thanks for your answer

Answer

Dear questioner,
in the following you find the answer from Dr. Silke Besier, to whom we have forwarded your question:
"The question goes into the region of hygiene. Therefore I contacted additionally our hygiene specialist Mr. Brandt.
We are of the opinion, that the usage of such a device has to be judged as critical. It is known however, that UV-C can kill bacteria, unfortunately there are only a few studies dealing with that topic in the field of medicine. One study (Andersen BM et al., Comparison of UV C light and chemicals for disinfection of surfaces in hospital units, Infect Control Hosp Epidemiol 2006) comes to the conclusion, that UV-C can admittedly reduce the bacterial contamination on surfaces, however should only be used in combination with chemical (wipe-)disinfection. The UV-C method is namely not better than a chemical disinfection (maximum as good as) and at certain surface textures not sufficient.

In addition, it is reported in the literature, that different species of bacteria have to be irradiated with a different intensity in order to at last kill the bacteria. Therefore the described usage of the UV-C wand seems to be to simple to me. E.g. the exposure time is very short (our sterile surfaces are irradiated with UV-C light for at least one hour after a prior chemical wipe disinfection).

I see another problem in the exact adherence of the needed distance. In addition it can be suspected that the device will have problems with the different kinds of textures of surfaces (e.g. the mentioned teddy bear). I think, that with that devices you lull yourself rapidly into a false sense of security. [end of the answer of Dr. Besier]
We hope to have helped you further,
Yours sincerely,
ECORN-CF

25.06.2009