Could this ICU disinfectant procedure increase antibiotic-resistant infections?

European researchers are calling for a reassessment of healthcare guidelines after revealing that an ICU disinfectant procedure used in certain countries may increase antibiotic-resistant infection risk.

‘Universal decolonisation’ is a preventive procedure applied to patients upon admission to intensive care in which the entire body is disinfected with chlorhexidine — a commonly used antiseptic also employed to sanitise hospital surfaces and medical devices — and an additional nasal treatment is administered with another disinfectant, mupirocin. The procedure is at the centre of a study published in The Lancet Microbe.

“Our research highlights the unintended consequences of universal decolonisation in a global context where antibiotic resistance is an increasing threat,” said Marco Oggioni, one of the authors of the study and a professor at the Department of Pharmacy and Biotechnology at the University of Bologna. “Coordinated efforts to prevent antibiotic-resistant infections are crucial, but they must not prevent us from critically re-evaluating the tools we use to achieve these goals.”

Introduced in the 1990s, universal decolonisation has proven effective in curbing the spread of methicillin-resistant Staphylococcus aureus (MRSA, a bacterium resistant to certain antibiotics that can cause severe infections), reducing MRSA infection rates from 30–40% to below 5% in many countries — Scotland included, which is where this study was conducted.

“Currently, UK healthcare facilities take different approaches: some hospitals apply universal decolonisation to all patients, while others take a more targeted approach, decolonising only those who test positive for MRSA,” Oggioni explained. “As a result, hospitals adopting universal decolonisation use significantly larger volumes of disinfectants such as chlorhexidine and mupirocin.”

In the study, researchers focused on two Scottish hospitals using these different approaches, comparing bacterial infection levels and antibiotic resistance rates among ICU patients over a 13-year period. They found higher rates of infection caused by the superbug methicillin-resistant Staphylococcus epidermidis (MRSE) in the hospital practising universal decolonisation; MRSE being less well-known than MRSA, but increasingly common and resistant to several types of antibiotics.

“Our findings show that the excessive use of disinfectants in universal decolonisation may not improve infection control, and instead leads to a rise in MRSE infections,” said Professor Karolin Hijazi from the University of Aberdeen, who coordinated the study. “In intensive care settings where the risk of MRSA infection is low, indiscriminate use of decolonisation procedures may not only be ineffective but also potentially harmful.”

According to Oggioni, this applies to regions where MRSA prevalence is low, like Scotland. “In Italy, however, MRSA infection risk remains high despite a downward trend, which means both targeted and universal decolonisation are still necessary,” Oggioni said. “We’ll need to reduce MRSA prevalence in Italy before we can reassess the risks and benefits of these intervention procedures.”

A reassessment of current practices in light of the evolving epidemiological landscape is therefore being called for by the study’s researchers, who believe new standardised guidelines are needed to identify the most effective decolonisation treatments — weighing both the benefits in infection control and the potential impact on antibiotic resistance.

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‘Universal versus targeted chlorhexidine and mupirocin decolonisation and clinical and molecular epidemiology of Staphylococcus epidermidis bloodstream infections in patients in intensive care in Scotland, UK: a controlled time-series and longitudinal genotypic study’, has been published open access in The Lancet Microbe and you can read it at doi.org/10.1016/j.lanmic.2025.101118.

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Image credit: iStock.com/Tempura