Boffins: Blue light kills MRSA 'superbugs'

American medi-boffins say they have developed a way to kill so-called "superbugs" - deadly infections which can't be cured using antibiotics - by simply shining a certain wavelength of blue light on them. They believe the technique could be used safely on patients infected with MRSA*.

"It is inspiring that an inexpensive naturally visible wavelength of light can eradicate two common strains of MRSA. Developing strategies that are capable of destroying MRSA, using mechanisms that would not lead to further antibiotic resistance, is timely and important for us and our patients," says Chukuka S Enwemeka PhD of the New York Institute of Technology.

Enwemeka and his colleagues had already shown that you can zap MRSA using a 405-nanometre blue light diode. Unfortunately a 405-nm superluminous diode emits light in the range 390-420 nm, which includes some ultraviolet (UV). There's not much point curing someone of a superbug infection if you wind up giving them skin cancer in the process.

But now, according to the New York-based boffinry crew, they have shown that two important strains of MRSA - one of the sort people catch in hospitals, another more commonly picked up "in the community" - can be fried out of existence using a 470-nanometre superluminous diode, which is safely clear of the UV band.

According to their research paper, available free online in advance of publication:

Conclusion: At practical dose ranges, 470-nm blue light kills HA-MRSA and CA-MRSA in vitro, suggesting that a similar bactericidal effect may be attained in human cases of cutaneous and subcutaneous MRSA infections.

Goodness knows whether this can really be turned into a useful therapy, but it seems interesting. And it would appear to hint that at least a few places in modern society are fairly unlikely to harbour deadly flesh-eating superbugs. The underside of a socially-disadvantaged youth's car, for instance; or perhaps the roof of the responding ambulances and police vehicles. ®

*Methicillin-Resistant Staphylococcus aureus, one of the more serious superbugs, resistant not only to penicillin but also the more modern, arse-kickinger methicillin.