Healthcare-associated infections (HAIs) pose a substantial challenge for modern medicine. Approximately 5 % of all patients in German hospitals acquire a HAI [1], although theoretically 35-55% of those infections could have been prevented by improving hygiene measures [2]. Since many microorganisms can persist on surfaces for long periods and, thus, be transmitted from person to person, proper routine cleaning and disinfection can contribute to combat HAIs.

Ojan Assadian and a team of experts have collected recommendations for routine and targeted cleaning and disinfection on general wards as well as for outbreak situations [3]. The authors based their suggestions on scientific literature and official guidelines of the World Health Organization (WHO), the Centers for Disease Control and Prevention (CDC), and the Kommission für Krankenhaushygiene und Infektionsprävention (KRINKO).

A comprehensive risk analysis is a key factor

The complex procedure of risk assessment was divided into three essential pillars: (I) patient risk profile, (II) surface risk profile, and (III) pathogen risk profile (see figure). These three components are intimately interconnected and should always be considered in combination.

With respect to the three risk profiles, the risk potential of a surface can be defined from different perspectives. A general ward, for instance, can be considered as moderate risk area, while wards accommodating immune-suppressed patients or receivers of bone marrow donations are classified as high-risk areas requiring intensive cleaning and disinfection. Further, low-touch and high-touch surfaces need to be distinguished: low-touch surfaces are often outside of the patient zone and rarely touched by bare skin, like walls or floors. High-touch surface are close to patients and/or are often in contact to the skin of patients or staff members (e.g., bed rails, door handles, light switches, but also lift buttons). However, even low-touch surface can become critical due to their contact to body fluids or needles or when these surfaces are used for preparation of critical applications, for example intravenous catheters. Risk assessment must account for this, too.

In case of an outbreak or when infections with clinically relevant pathogens (e.g., MRSA) are observed, a targeted cleaning and disinfection is necessary. Pathogen-specific recommendations are also provided by the authors.

Both important: Equipment and staff

Irrespective of whether routine or targeted measures, the adequate equipment is crucial and relies on the correct choice of surface disinfectants. Therefore, the authors summarised established chemical disinfectants and listed their benefits and disadvantages. In addition, recommendations are given for disposable and reusable products (i.e., wipes or mops) and when to use which type. All products and agents need sufficiently trained staff members to be applied correctly in order to successfully prevent transmission of HAIs. Next to regular training, adequate staff ratio, remuneration, supervision, and team communication are mandatory. The cleaning and disinfection need to be monitored on a regular basis allowing for timely feedback. Common methods to assess cleanliness are microbiological sampling, ATP-based assays, or fluorescent markers.