Hand sanitisers being used to try and keep infections at bay on hospital wards are becoming increasingly useless as ‘superbug’ bacterias are proving resistant to them.

Scientists have found that the fight against dangerous infections is becoming increasingly difficult, as a new wave of vancomycin-resistant enterococcus (VRE) has developed in the last 20 years. And it can survive against hand sanitisers. 

As these bacteria evolve, they go through changes in their genetic makeup, which means they are no longer killed by the alcohol-based hand washes.

Medical institutions worldwide started adopting stringent hygiene steps – involving hand rubs and washes that contain alcohol – in the last ten years, in a bid to tackle VRE and other bugs like MRSA. 

While this approach has been affective in stabilising the levels of MRSA, VRE infection rates have not been affected in the same way.

VRE is dangerous as it can cause urinary tract, wound and bloodstream infections that are notoriously difficult to treat, mainly because they are resistant to several classes of antibiotics.

This prompted Tim Stinear, a microbiologist at the Doherty Institute in Australia to investigate the VRE bug for potential resistance to disinfectant alcohols.

They screened 139 isolated bacterial samples collected between 1997 and 2015 from two hospitals in Melbourne and studied how well each one survived when exposed to diluted isopropyl alcohol. 

They found that samples collected after 2009 were on average more resistant to the alcohol compared with bacteria taken from before 2004.

The scientists then spread the bacteria onto the floors of mouse cages and found that the alcohol-resistant samples were more likely to get into, and grow in the guts of the mice after the cages were cleaned with isopropyl alcohol wipes.

Despite the findings, scientists say this shouldn’t prompt hospitals to stop using the products altogether. Professor Paul Johnson, who also co-led the study, said the findings should not prompt any dramatic change in the use of alcohol-based disinfectants.

“Alcohol-based hand rubs are international pillars of hospital infection control and remain highly effective in reducing transmission of other hospital superbugs, particularly MRSA,” he said.

Instead they suggested trying higher-alcohol concentrate products and renewed efforts to deep clean hospitals while isolating patients found to carry VRE. 

Their findings were published on Wednesday in the journal Science Translational Medicine.