Disinfectants may increase antibiotic resistance

Disinfectants are not always our friends. If they allow us to live in a clean environment, the chemical substances they contain are not without danger for our organism. A recent study, published on October 27 in the journal EBioMedicinereveals a double effect of these products: they promote resistance to antibiotics and prevent these drugs from acting.

A problem for critically ill and immunocompromised patients

It is a looming threat, against which the World Health Organization (WHO) has been trying to warn for several years: the worsening of the antibiotic resistance of pathogenic bacteria which could cause new pandemics in the years to come. Among the resistant bacteria is a group known as ESKAPE pathogens for the initials of each of the bacteria that make up this group (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacter). While usually harmless, they can lead to life-threatening illness if caught by an already seriously ill or immunocompromised patient who can then develop pneumonia, sepsis and wound infections.

Australian researchers from Macquarie University tested the effects of the disinfectant product benzalkonium chloride (BAC) on ESKAPE pathogens. “BAC is a biocidal disinfectant valued for its non-toxicity and therefore it is widely used in healthcare, food safety and agriculture, as well as in common household products such as antibacterial wipes, disinfectants for wounds, eye drops and ear drops”, adds Francesca Short, researcher in molecular sciences and author of the study.

Hazardous substances even in low doses

The results of the study showed that BAC can prevent aminoglycoside antibiotics, particularly used against staphylococci, from working. This product could also promote the evolution of resistant bacteria, “which is extremely concerning given their wide use”, worries Ian Paulsen, co-author of the study. Researchers have found that even at low doses, BAC can prevent aminoglycosides from doing their job because it prevents antibiotics from entering the bacterial cell.

The team found that even when given at low levels, BAC can prevent aminoglycosides from doing their job because it prevents antibiotics from entering the bacterial cell. “It also greatly increases the frequency with which new potentially resistant mutants emerge.continues Ian Paulsen. Our results suggest that steps should be taken to prevent exposure of bacteria to lower levels of BAC – levels that are not high enough to kill bacteria but may be high enough to allow mutations to occur or help bacteria to gradually get used to the effects of antibiotics.”

In France, the decline in antibiotic consumption is accelerating

At the same time as the publication of this study, we also learned that the consumption of antibiotics fell in France in 2020. This trend, which has been observed for several years, has been accentuated during the health crisis. This Tuesday, Public health France published data from reimbursements made by Social Security, which shows the consumption of antibiotic drugs. These reveal a drop of 17% in consumption and 18% in prescriptions.

This decrease is explained first of all by a direct effect of barrier gestures and confinements which have reduced the spread of other diseases and therefore the need for antibiotics. These measures would also have discouraged the French from consulting a doctor, “especially during the first lockdown“, says Public Health France. Despite this drop, France remains one of the biggest consumers of antibiotics with consumption nearly a third higher than the European average.