Share thisProtecting your laboratory against infectious agents and parasites can help maintain the integrity of your research.
Laboratory animal facility biosecurity, intended to protect rodents used in research from infectious agents and parasites, impacts the animals, the personnel in contact with them, and the research. Specific pathogen-free (SPF) rodents for modern biomedical research need to be free of pathogens and other infectious agents that may not produce disease but nevertheless cause research interference. To meet this need, rodents have to be rederived to eliminate adventitious agents and then housed in room- to cage-level barrier systems to exclude the microbial contaminants. Because barriers can and do fail, routine health monitoring (HM) is necessary to verify the SPF status of colonies. Testing without strict adherence to biosecurity practices, however, can lead to the inadvertent transfer of unrecognised, inapparent agents among institutions and colonies. Microisolation caging systems have become popular for housing SPF rodents because they are versatile and provide a highly effective cage-level barrier to the entry and spread of adventitious agents. But when a microisolationcaged colony is contaminated, the cage-level barrier impedes the spread of infection and so the prevalence of infection is often low, which increases the chance of missing a contamination and complicates the corroboration of unexpected positive findings. The expanding production of genetically engineered mutant (GEM) rodent strains at research institutions, where biosecurity practices vary and the risk of microbial contamination can be high, underscores the importance of accurate health monitoring results in mitigating the risk of the introduction and spread of microbial contaminants with the exchange of mutant rodent strains among investigators and institutions. Here I would like discuss biosecurity risks, recommendations and requirements for facility maintenance, and quality assurance of laboratory animals.
RECOMMENDATIONS AND REQUIREMENTS FOR FACILITY MAINTENANCE
Room-level barrier to infection entails HEPA filtration of incoming air, disinfection of room equipment and supplies, and trained, properly gowned personnel. The barrier facility should consist of differential pressure maintained across the corridors. The personnel and material entry and exit should be one way. The opening of the door in the clean and dirty corridor should be used properly and needs to be closed immediately, otherwise the pressure drops and barrier will not be maintained which favors pathogen transfer from one room to another or corridor to room. Also there must be frequent monitoring of the differential pressure in between the corridor and rooms. Disinfectants and sanitisers are effective against vegetative bacterial cells, but have very limited efficacy against bacterial spores. Sterilants, the third category of surface decontaminants, have a biocidal effect against bacterial spores. Some examples of sterilants are chlorine dioxide, peracetic acid, formalin, hydrogen peroxide, and gluteraldehyde based products. The barrier gowning procedure should include sterile or autoclaved foot covers, face mask, and head cover. Once the gown is used, it should be discarded or autoclaved for further use.