Using reduced personal protective equipment in an endemically infected mouse colony

Abstract

Personal protective equipment (PPE) frequently is used to reduce the risk of spreading adventitial diseases in rodent colonies. The PPE worn often reflects the historic practices of the research institution rather than published performance data. Standard PPE for a rodent facility typically consists of a disposable hair bonnet, gown, face mask, shoe covers, and gloves, which are donned on facility entry and removed on exiting. This study evaluated the effect of a reduced PPE protocol on disease spread within an endemically infected mouse colony. In the reduced protocol, only the parts of the wearer that came in direct contact with the mice or their environment were covered with PPE. To test the reduced PPE protocol, proven naïve mice were housed in a facility endemically infected with murine norovirus and mouse hepatitis virus for 12 wk. During that time, routine husbandry operations were conducted by using either the standard or reduced PPE protocols. All study mice remained free of virus antibody when reduced PPE was implemented. These results indicate that reduced PPE is adequate for disease containment when correct techniques for handling microisolation caging are used. Reducing the amount of PPE used in an animal facility affords considerable cost savings yet limits the risk of disease spread.

Figure 1.

Seroconversion rates (mean ± SEM) of dirty-bedding sentinels during the study period, according to virus and level of PPE. There was no significant difference between the sPPE and rPPE groups for either MNV or MHV.

Figure 2.

Seroconversion rates (mean ± SEM) for dirty-bedding sentinels to MNV (red) and MHV (blue) over preceding years. 2013 quarter 1 represents the time when the sPPE study animals were housed, and 2013 quarter 2 represents rPPE. No significant difference was seen in average MNV or MHV seroconversion rates for the 2-y period leading up to the study or between the study period and the preceding 2 y.