Research shows that bacteria survive longer in contact lens cleaning solution than thought

April 16, 2014

Each year in the UK, bacterial infections cause around 6,000 cases of a severe eye condition known as microbial keratitis – an inflammation and ulceration of the cornea that can lead to loss of vision. The use of contact lenses has been identified as a particular risk factor for microbial keratitis. New research, presented today at the Society for General Microbiology Annual Conference in Liverpool, shows that a bacterial strain associated with more severe infections shows enhanced resistance to a common contact lens disinfectant solution.

Researchers from The University of Liverpool and The Royal Liverpool University NHS Trust tested different of the keratitis-causing bacterium Pseudomonas aeruginosa for their ability to survive in a commonly used contact lens cleaning solution. The team compared nine clinical strains of P. aeruginosa, taken from hospital patients in the UK, with P. aeruginosa strain 9027, the standard strain used by lens solution manufacturers.

The results showed that the majority of clinical strains tested were killed within 10 minutes of being immersed in the contact lens solution, comparable with the standard reference strain. However, one clinical isolate, P. aeruginosa strain 39016 – associated with a more severe case of keratitis with a prolonged healing time – was able to survive for over four hours, much longer than the reference strain.

There are more than 3 million people in the UK using . This work suggests that clinically-relevant isolates with enhanced resistance should be included when testing the efficacy of contact lens cleaning solutions to ensure that the procedures are sufficiently robust to kill all P. aeruginosa strains.

Professor Craig Winstanley, who led the research, says: "Microbial keratitis can be devastating for a patient – it is important that the risk of developing this condition is reduced in contact lens wearers by improving disinfectant solutions."

The research group plan to investigate further isolates to find out how widespread the enhanced bacterial resistance is and to better understand the mechanisms underlying it. This will potentially help in the design of more effective disinfectant procedures.

Explore further: Don't take shortcuts when caring for contact lenses, expert says

More information: Professor Winstanley's PhD student Amanda Hall is presenting a poster entitled 'A virulent keratitis-associated strain of Pseudomonas aeruginosa exhibits prolonged survival time in contact lens fluid' at the Society for General Microbiology's Annual Conference 2014.

Related Stories

Don't take shortcuts when caring for contact lenses, expert says

November 24, 2012
(HealthDay)—Common shortcuts people take when caring for their contact lenses could have serious consequences, such as infections or ulcerations, according to an eye disease expert.

Contacts uncomfortable? Changing lens type or lens care product may help

May 1, 2013
If your contact lenses are causing you discomfort, simply switching to a different type of contact lens or lens care product may bring improvement, reports a study, " Effect of Lens and Solution Choice on the Comfort of Contact ...

Recommended for you

Research examines lung cell turnover as risk factor and target for treatment of influenza pneumonia

July 24, 2017
Influenza is a recurring global health threat that, according to the World Health Organization, is responsible for as many as 500,000 deaths every year, most due to influenza pneumonia, or viral pneumonia. Infection with ...

Scientists propose novel therapy to lessen risk of obesity-linked disease

July 24, 2017
With obesity related illnesses a global pandemic, researchers propose in the Journal of Clinical Investigation using a blood thinner to target molecular drivers of chronic metabolic inflammation in people eating high-fat ...

Raccoon roundworm—a hidden human parasite?

July 24, 2017
The raccoon that topples your trashcan and pillages your garden may leave more than just a mess. More likely than not, it also contaminates your yard with parasites—most notably, raccoon roundworms (Baylisascaris procyonis).

Google searches can be used to track dengue in underdeveloped countries

July 20, 2017
An analytical tool that combines Google search data with government-provided clinical data can quickly and accurately track dengue fever in less-developed countries, according to new research published in PLOS Computational ...

MRSA emerged years before methicillin was even discovered

July 19, 2017
Methicillin resistant Staphylococcus aureus (MRSA) emerged long before the introduction of the antibiotic methicillin into clinical practice, according to a study published in the open access journal Genome Biology. It was ...

New test distinguishes Zika from similar viral infections

July 18, 2017
A new test is the best-to-date in differentiating Zika virus infections from infections caused by similar viruses. The antibody-based assay, developed by researchers at UC Berkeley and Humabs BioMed, a private biotechnology ...

0 comments

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.