Surface material The RC not only differs significantly between different pathogens, but is also influenced by numerous external factors. For example, it is known that copper surfaces significantly shorten the RC of pathogens compared to textiles, plastic or steel. The nature of the surface also plays a role, with viruses in particular benefiting from greater porosity [1]. Humidity and temperature Thanks to their cell walls, Gram-positive bacteria tolerate dry conditions better than Gram-negative bacteria. Viruses are also influenced by their envelope:Enveloped viruses, especially respiratory pathogens, maintain their RC longer at low humidity, while non-enveloped viruses require more humid air. In addition, lower temperatures appear to be more favorable for the RC of airborne bacteria and certain viruses. SARS-CoV-2, for example, remains infectious longest at low temperatures and extremely high humidity. Enteric viruses, on the other hand, which spread mainly faecal-orally, multiply particularly well from 20 °C [1]. Biofilms Biofilms not only ensure the survival of pathogens in their natural habitat, but also in healthcare facilities. For example, they protect them from environmental factors such as dryness. Klebsiella pneumoniae, for example, can remain viable in a dry biofilm for up to 4 weeks. Biofilms therefore require particularly thorough cleaning methods [1]. Systematic review of the environmental resilience of nosocomial pathogens How long can bacteria & co. multiply on surfaces? Contaminated surfaces play an important role in the spread of nosocomial infections (NI). The risk of NI depends on various factors such as exposure, the degree of contamination and the infectious dose. The decisive factor, however, is whether the pathogens on surfaces are still viable and even able to multiply. A current systematic review [1] now provides a comprehensive overview of numerous relevant bacteria, viruses, fungi and protozoa and their capacity to replicate (RC) on surfaces. Following further scientific discussion, recommendations for the cleaning and disinfection of surfaces should be derived from this in the future. KNOWLEDGE Reference 1. Kramer A et al. (2024) Clin Microbiol Rev 37: e0018623. https://doi.org/10.1128/cmr.00186-23 Timeline of replication capacity of pathogens on surface xy at room temperatute (schematic illustration) Timeline of replication capacity of pathogen xy on different surfaces at room temperatute (schematic illustration) 1 minute 1 hour 1 week 1 month 1 year 1 minute 1 hour 1 week 1 month 1 year 13
RkJQdWJsaXNoZXIy NDU5MjM=