Methodology for Health Monitoring of mice maintained in IVCs

New challenges appeared with the housing of mice in Individually Ventilated Cages (IVC), since the equipment is designed to reduce the spreading of microbes (i.e. virus, bacteria, parasites and fungi). New sampling strategies rely on the use of environmental samples (e.g. from cage, plenum, or exhaust air dust) to mitigate the risk of false negatives due to the lack of microbial transmission between colony and sentinel animals housed in IVC. And there are some 3Rs considerations that should be discussed when setting up a screening strategy. In order to help research establishments monitor the health (including microbiological status) of mice maintained in IVCs, the working group will evaluate, through literature review, the advantages and disadvantages of the different strategies, the suitability of samples for respective microbes, how sampling should be conducted (e.g. techniques, numbers, frequency and assays), how sentinel welfare and exposure can be improved, and how non-infectious diseases can be monitored. The working group will propose a template to report health monitoring data with information on sample origin, material, techniques and assays. Finally, with the 3Rs at heart, the working group will recommend a methodology to combine health monitoring strategies in order to demonstrate a Specific Pathogen-Free (SPF) status.