Handwash sanitisers commonly used in hospitals are becoming increasingly ineffective against a notorious superbug, research has shown.
Scientists in Australia made the discovery after testing bacterial samples collected over a period of 19 years.
They found strong evidence that the superbug vancomycin-resistant enterococcus (VRE) is growing increasingly immune to alcohol-based disinfectants.
Enteroccocus bacteria (Wikimedia Commons/PA)
VRE infections are some of the most difficult to treat because the bacteria are resistant to many classes of antibiotic, including the “last resort” drug vancomycin.
To combat dangerous microbes, hospitals in the UK and around the world have adopted strict hand-hygiene procedures.
These generally involve hand rubs or washes containing ethyl or isopropyl alcohol disinfectants.
The Australian team screened 139 Enterococcus samples collected from two hospitals between 1997 and 2015 to see how well the bugs survived when exposed to diluted isopropyl alcohol.
Those obtained after 2009 were found to be more tolerant to the disinfectant than those sampled before 2004.
In another part of the study, bacteria were seeded on the floors of laboratory mouse cages.
Alcohol-tolerant microbes were better able to colonise the guts of mice after the cages were cleaned with disinfectant wipes.
Professor Paul Johnson, a member of the team from Australian health service provider Austin Health, said: “Alcohol-based hand rubs are international pillars of hospital infection control and remain highly effective in reducing transmission of other hospital superbugs, particularly methicillin resistant Staphylococcus aureus (MRSA).”
The researchers traced the increased resistance to alcohol-based disinfectants to several Enterococcus mutations in genes that play a role in metabolism.
Lead scientist Professor Tim Stinear, from the Doherty Institute in Melbourne, described the sanitiser-resistant VRE strains as “a new wave of emerging superbugs”.
He added: “Alcohol-based hand hygiene use has increased tenfold over the past 20 years in Australian
hospitals, so we are using a lot and the environment is changing.”
Writing in the journal Science Translational Medicine, the team said efforts to combat superbugs should focus on how bacteria become resistant to disinfectants as well as antibiotics.
Why are you making commenting on The Herald only available to subscribers?
It should have been a safe space for informed debate, somewhere for readers to discuss issues around the biggest stories of the day, but all too often the below the line comments on most websites have become bogged down by off-topic discussions and abuse.
heraldscotland.com is tackling this problem by allowing only subscribers to comment.
We are doing this to improve the experience for our loyal readers and we believe it will reduce the ability of trolls and troublemakers, who occasionally find their way onto our site, to abuse our journalists and readers. We also hope it will help the comments section fulfil its promise as a part of Scotland's conversation with itself.
We are lucky at The Herald. We are read by an informed, educated readership who can add their knowledge and insights to our stories.
That is invaluable.
We are making the subscriber-only change to support our valued readers, who tell us they don't want the site cluttered up with irrelevant comments, untruths and abuse.
In the past, the journalist’s job was to collect and distribute information to the audience. Technology means that readers can shape a discussion. We look forward to hearing from you on heraldscotland.com
Comments & Moderation
Readers’ comments: You are personally liable for the content of any comments you upload to this website, so please act responsibly. We do not pre-moderate or monitor readers’ comments appearing on our websites, but we do post-moderate in response to complaints we receive or otherwise when a potential problem comes to our attention. You can make a complaint by using the ‘report this post’ link . We may then apply our discretion under the user terms to amend or delete comments.
Post moderation is undertaken full-time 9am-6pm on weekdays, and on a part-time basis outwith those hours.
Read the rules here