Test methods for efficacy assessment of antimicrobial coatings are not modelled on a hospital environment, and instead use high humidity (>90%) high temperature (37 °C), and no airflow. Therefore, an inoculum will not dry, resulting in an antimicrobial surface exhibiting prolonged antimicrobial activity, as moisture is critical to activity. Liquids will dry quicker in a hospital ward, resulting in a reduced antimicrobial efficacy compared to
Performance Assessment …
Background
Current and new antimicrobial coatings (AMC) will only either enter the healthcare market or have an impact on hygiene and hospital acquired infections if their efficacy can be shown in appropriate (field) testing. However, testing AMCs in a healthcare environment has ethical and practical issues. In order to allow proper testing of the efficacy of an AMC it is essential to know the problem that the coated material is intended to solve. In addition, the expected site of intervention (e.g. surfaces, textiles, clothing) as well as other factors (eg cleaning and disinfection, environmental conditions etc) will have an influence on the effect intended. Many (standardised) methods are available that can detect antimicrobial properties of a large diversity of materials although a much smaller sub-set are suited to examining hygienic or self disinfecting properties. It is often difficult to decide which method should be employed to explore the effect of a certain material-coating combination in a certain environment and methods must usually be modified to demonstrate effects in practice. Furthermore, none of the methods available seem to be really suitable to predict the overall efficacy on bacterial contamination in the hospital and/or care environment. This calls for guidelines related to use and/or the design of reliable tests that can be used to evaluate and compare the effect of AMCs (e.g. impact, durability, etc.).
The AMICI action members in workgroup 2 (WG2) will therefore work on the collection of current methods, both lab-based and field-based assays. They will then be ranked and benchmarked, in relation to the use of a certain assay, to enable a better understanding of their applicability to sue in examining claims made for the performance of AMCs and to help guide the development priorities for new methods.
Objectives
AMICI WG 2 aims to identify appropriate testing methods / models for laboratory and field-based assays.
Deliverables
• Collection of current methods
– Standard and others (including publications)
– What they are used for (dental, hospital etc.)
– Durability (what approaches are used)
• Create a portfolio
– Suitability for end uses / ranking of existing methods
• Create a guidance document
The first period of the project will focus on lab-based assays and the second period on field-based assays.
WG2 Leader:
Peter D. Askew, Managing Director IMSL LTD,
WG2 V-Leader:
Dr. Birgit E.J. Teunissen, Business Development Manager CHILL,
WG Members:
Haavard Jenssen,
Jose Javier Serrano Olmedo
Bill Keevil
Jurate Siugzdaite
Josette Camilleri
Cher Farrugia
Gabriel Furtos
Luminita Nica
Ugur Tamer
Heidi Van den Rul
Join us?
We invite everyone who is experienced with the testing of antimicrobial coatings and/or other materials to either become part of the AMICI consortium and/or to share their experiences with us. For further information on WG2 Performance assessment please contact Pete Askew (link to contact info) or Birgit Teunissen (link to contact info).