Blue light destroys antibiotic-resistant staph infection

Jan 29, 2009

Two common strains of methicillin-resistant Staphylococcus aureus, commonly known as MRSA, were virtually eradicated in the laboratory by exposing them to a wavelength of blue light, in a process called photo-irradiation that is described in a paper published online ahead of print in Photomedicine and Laser Surgery. The article will appear in the April 2009 issue (Volume 27, Number 2) of the peer-reviewed journal published by Mary Ann Liebert, Inc.

Antibiotic-resistant bacterial infections represent an important and increasing public health threat. At present, fewer than 5% of staphylococcal strains are susceptible to penicillin, while approximately 40%-50% of Staph aureus isolated have developed resistance to newer semisynthetic antibiotics such as methicillin as well.

Chukuka S. Enwemeka, Deborah Williams, Sombiri K. Enwemeka, Steve Hollosi, and David Yens from the New York Institute of Technology (Old Westbury, NY) had previously demonstrated that photo-irradiation using 405-nm light destroys MRSA strains grown in culture. In the current study, "Blue 470-nm Light Kills Methicillin-Resistant Staphylococcus aureus (MRSA) in Vitro," the authors exposed bacterial colonies of MRSA to various doses of 470-nm light, which emits no UV radiation.

The two MRSA populations studied—the US-300 strain of CA-MRSA and the IS-853 strain of HA-MRSA—represent prominent community-acquired and hospital-acquired strains, respectively.

The authors report that the higher the dose of 470-nm blue light, the more bacteria were killed. High-dose photo-irradiation was able to destroy 90.4% of the US-300 colonies and the IS-853 colonies. The effectiveness of blue light in vitro suggests that it should also be effective in human cases of MRSA infection, and particularly in cutaneous and subcutaneous infections.

"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, FACSM, Co-Editor-in-Chief of the Journal and first author of the study.

The paper is available free online at www.liebertpub.com/pho.

Source: Mary Ann Liebert

Explore further: Most people want it, but the UK isn't ready to legalise assisted dying

Related Stories

Ecologists develop new method for mapping poaching threats

14 minutes ago

Ecologists from the University of York, together with the Wildlife Conservation Society (WCS) and the Uganda Wildlife Authority (UWA), have developed a new method to better identify where poachers operate in protected areas.

Estuaries protect Dungeness crabs from deadly parasites

14 minutes ago

Parasitic worms can pose a serious threat to the Dungeness crab, a commercially important fishery species found along the west coast of North America. The worms are thought to have caused or contributed to ...

Top UK scientists warn against EU exit

18 minutes ago

A group of leading British scientists including Nobel-winning geneticist Paul Nurse warned leaving the European Union could threaten research funding, in a letter published in The Times newspaper on Friday.

Adult dating website hack exposes personal data

4 minutes ago

A data breach at a website billed as "the world's largest sex and swinger" community may expose personal and sexual information on millions of users worldwide, a report said Friday.

Recommended for you

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.