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Resistant super bacteria make alcoholic disinfectants increasingly ineffective


Hand gel disinfectants with alcohol are becoming increasingly ineffective

Disinfectants with alcohol are used especially in hospitals to prevent the dangerous spread of germs and bacteria. However, these disinfectants seem to be increasingly ineffective against so-called super-pathogens.

The University of Melbourne scientists found in their current investigation that alcohol-based disinfectants are less and less effective against certain pathogens in hospitals. These disinfectants were actually said to prevent thousands of deaths from MRSA bacteria. The doctors published the results of their study in the English-language journal "Science Translational Medicine".

Disinfectants with alcohol are important for controlling infections

Evidence is mounting that bacteria are already resistant to hand disinfectants with alcohol, experts say. Such disinfectants are indispensable for controlling infections, especially in hospitals. The researchers made this disturbing finding when they investigated why some types of antibiotic-resistant bacteria have become a growing threat in Australian hospitals despite the widespread use of hand gel disinfectants.

Investigation focused on enterococci

Doctors focused on a group of gut bacteria known as enterococci. These intestinal bacteria are a growing problem around the world because they are even increasingly resistant to treatment with the latest antibiotics, such as the drug vancomycin. When studying bacterial samples from Australian hospitals over a period of 19 years, the scientists found that the bacteria can now survive much better in sterile environments and cause infections. If this trend continues, hospitals could no longer rely on these measures to prevent outbreaks from becoming infected, the authors warned.

Disinfectants with alcohol have reduced death rates from MRSA

Hand gel disinfectants with alcohol have been a major ingredient in hospitals around the world since the mid-2000s. An international handwashing initiative helped reduce the number of common super-pathogens (such as MRSA) that caused thousands of deaths each year. Across the country, MRSA rates have declined, benefiting patients and reducing the risk of serious infections, said study author Professor Paul Johnson of the University of Melbourne.

Enterococci are the fifth largest cause of sepsis in Europe

The physicians also noticed a gradual increase in infections from vancomycin-resistant enterococci, which appeared to be a paradox since both infections should be controlled by normal hand hygiene. The enterococci are already the fifth largest cause of sepsis in Europe and account for ten percent of the blood poisoning (bacteremia) acquired in hospitals worldwide, the experts explain.

Resistance to vancomycin is a major problem

In addition, vancomycin resistance is a major problem since vancomycin is one of the few antibiotics that can be used to treat bacteria with more complex cell walls, such as E. coli and enterococci. Bacteria can also share resistance genes between species and allow a resistant species to spread, which means that other bacteria are also more difficult to treat.

Further examinations in other hospitals are necessary

E faecium is one of the main causes of infections. The researchers tested E faecium's tolerance to disinfection by inserting the bacteria into mouse cages that had been sterilized with conventional alcohol solutions. It turned out that modern types of these bacteria continued to grow and were better able to colonize the intestines of infected mice, where they could cause and pass on infections. This could be due to the bacteria becoming more resistant to alcohol gels due to their increasing use, or it could be that they have adapted to the conditions in our bodies that happen to help them better withstand disinfectants. The authors of the study explain that it is now necessary to check whether the same patterns of alcohol tolerance occur in other hospitals worldwide. (as)

Author and source information

Video: Unlocking the secrets of superbugs. Claire Gorrie. TEDxStKilda (August 2020).