In the early 2000s, hospitals throughout Australia began to install hand sanitizer dispensers in rooms and corridors to allow access for staff, visitors and patients to remove bacteria from their hands. Research has shown that these alcohol-based disinfectants have helped fight staphylococcal infections in patients and in some types of drug-resistant bacteria and rates of these infections have decreased. However, some other infections have behaved in exactly the opposite way. We discussed this issue with Dr. Marta Noemi Monari, Clinical Technical Coordinator for the development of Group Laboratories and Services of Humanitas.
10% of infections do not react to soap
Enterococcal infections, i.e. infections caused by bacteria affecting the digestive tract, bladder, heart and other parts of the body, have begun to increase with the increased use of antibacterial soap.
These infections make up 10% of bacterial infections acquired in the hospital and in North America and Europe, are a major cause of sepsis, a deadly blood infection.
Was this the fault of the alcoholic base?
New research published by Science Translational Medicine claimed that several strains of seemingly soap-resistant bacteria in the hands had begun to adapt to alcohol-based hand sanitizers. This could mean that bacteria are able to survive for longer periods of time if they come into contact with the alcohol contained in the soaps.
A possible danger for hospitals
“This was the first time anyone has shown that hospital bacteria are becoming tolerant of alcohol in disinfectants,” said Timothy Stinear, co-author of the study and researcher at the Doherty Institute for Infection and Immunity at the University of Melbourne.
The researchers compared 139 types of bacteria, looking at the same strains over a period of 19 years: from 1997 to 2015. Over time, bacteria have evolved to better tolerate alcohol within disinfectants. Bacteria collected after 2009 were 10 times more tolerant than bacteria collected before 2004, which corresponds to the national push to use more hand sanitizers.