Antibiotics are used extensively in primary care, as well as in hospitals, but little is known about how the environmental consequences of antibiotic resistance are managed. These are the questions that the IRISSO team wants to explore.

Antibiotic resistance and the environment in the age of “One Health"

Since the early 2000s, the rise of the “One Health” concept has made a previously little-documented dimension of antibiotic resistance visible: its links with the environment. For a long time, antimicrobial resistance was conceived as a human or animal health problem, which needed to be prevented and treated to avoid the occurrence of fatal infections, without its environmental “component” being taken into account. The emerging interest in a “One Health ” approach stems from the fact that the environment can play an important role in the development of resistance. As Céline Jamet and Laura Barbier, from the Commissariat général au développement durable (French Ministry of Ecology and Sustainable Development), pointed out in a recent interview :

“The spread of antibiotic residues and resistant bacteria in the natural environment (water and soil) is thought to encourage antibiotic resistance: discharges of treated wastewater, spreading of sludge from wastewater treatment plants and livestock effluents... Environmental contamination by certain substances, such as biocides, is also thought to promote antibiotic resistance. But the mechanisms involved and our knowledge of environmental contamination remain to be studied in greater depth." [1] .

It is precisely these mechanisms and this knowledge of the environment that the “One Health” approach can help to document. With the benefit of hindsight, we are now aware that the three biggest sources of antibiotic discharges into the environment are livestock production, pharmaceutical manufacturing facilities and antibiotic treatments prescribed for human health. Organizations specializing in the promotion of healthcare practices that limit their environmental impact, such as Health Care Without Harm, point out, for example, that up to 90% of doses of orally administered medicines end up in wastewater [2]. With regard to hospitals, the NGO indicates that between 20% and 30% of patients receive antibiotic treatment during their stay. For these reasons, the STATIC project focuses on the links between antibiotic resistance and the environment in the context of hospital care, and the role that the “One Health” approach plays - or could play - in this context.

What antibiotic resistance means for hospitals

In recent years, a great deal of knowledge has been generated, particularly in France, on the consumption and discharge of antibiotics in the human health sector. This knowledge provides valuable material for understanding which antibiotics are consumed and discarded, and in what contexts. According to the Centre Régional en Antibiothérapie - Ile-de-France, set up in 2022, around ¾ of antibiotics prescribed in human health are prescribed by community doctors (i.e. outside hospitals), mainly by general practitioners, but also by dentists and other specialists [3]. In an attempt to reduce these prescriptions as much as possible, the CRAtb is deploying numerous initiatives (advice, training, promotion of tools such as Antibioclic®, etc.) aimed at healthcare professionals and pharmacists. The remainder of antibiotic consumption in human health is hospital-based.

The STATIC project focuses on the problem of antibiotic resistance in hospitals, because they have a number of specific features. First, hospital patients are generally at particularly high risk of contracting bacterial infections. There are many points of entry for bacteria: catheters and heavy surgical procedures, for example, can present a high risk of exposure (in gastroenterology, for example), and patients may also be very vulnerable, elderly or suffering from co-morbidities. A second specificity concerns the drugs they use: some of them are only dispensed in hospitals, often because of their potency or undesirable effects. The third specificity is methodological. Hospitals have well-defined geographical boundaries, which makes it easier to determine what's there (in terms of antibiotics and resistance), what's coming in and what's going out (via hospital effluents, for example).

How is antibiotic use actually controlled in hospitals, and how is antibiotic resistance addressed? A number of tools are available to help achieve these two objectives. Firstly, good practice guidelines: first-line antibiotics, biological samples (blood tests), antibiotic susceptibility tests to identify the bacteria of concern and their resistance, then, if necessary, a new, better-adapted antibiotic. It also involves, as in the livestock sector, policies to reduce the use of antibiotics (Boullier and Fortané, 2025). Since 2018, for example, the SPARES mission has been developing ConsoRes, which enables healthcare institutions to gain an overall view of their antibiotic use and possibly compare it with that of other hospitals. However, these tools are essentially focused on antibiotic prescription practices and the identification of resistance in patients, but do not necessarily integrate the environment into their analyses.

Research inside and outside the hospital

In recent years, there has been growing concern about the presence of antibiotics in the hospital environment - in water in particular. The STATIC surveys aim to gain a better understanding of the initiatives undertaken within hospitals - but also outside - to manage AMR, from a social science perspective.

The problem of antibiotic discharges into water is particularly acute in contexts where these are very significant. This is the case in India, for example, where industrial livestock farms use large quantities of antibiotics and drug production plants discharge their waste into the surrounding waters (see IFP team post). But this issue is not specific to the countries of the Global South: in France too, authorities and researchers are concerned about the pollution generated by healthcare activities, particularly in hospitals, even if the way in which the question has been formulated and the measures implemented are notoriously different. Surprisingly, however, little is known about the fate (the life cycle) of hospital effluents. Existing literature (microbiology, environmental sciences, pharmacy, etc.) has focused mainly on the content of effluent leaving the hospital, without taking an interest. To fill this gap, a first aim of STATIC's surveys is to investigate.

Before antibiotics are released in wastewater, hospitals implement a whole series of measures to prevent contamination - and thus limit the need for treatment. In hospital settings, particular attention is paid to the patient's environment, since infections affect people who are often weakened. To this end, doctors, pharmacists, nurses and biohygienists working in infectious risk prevention units work together with other departments to limit the presence of resistant bacteria in the hospital environment. The maintenance of surfaces (in patient wards, operating rooms, etc.) and medical devices is as much a necessity as it is a challenge, given the high risk of biological contamination during care (blood, feces, urine, etc.) and the development of biofilms, i.e. bacterial communities that manage to survive on apparently clean surfaces. As part of STATIC, the IRISSO team will study the knowledge and tools developed to manage resistant bacteria in the hospital “environment”.

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[1] Commissariat général au développement durable (2023) « L’antibiorésistance, c’est aussi une affaire d’environnement ! » (To be found here)

[2] Health Care Without Harm (2022) « AMR in the environment » (To be found here)

[3] CRAtb Ile-de-France (2024) (To be found here)