Murine chapparvovirus (MuCPV)/mouse kidney parvovirus (MKPV) eradication by cross foster rederivation

When diagnostic tests became available for the detection of mouse kidney parvovirus (MKPV), also known as murine chapparvovirus (MuCPV), we undertook a facility-wide screening to determine the prevalence of this novel agent in the Animal Resources Centre. MKPV was present only in the Customs Strains, specific-pathogen-free (SPF) barrier area, which was the only animal holding area that received mice imports directly from non-approved vendors. Based on this information, the knowledge and understanding of the viral epizootiology, and the testing methods available, we decided to eradicate MKPV after consultation with the researchers impacted. To eradicate MKPV from the barrier, we took a multi-modal approach composed of testing and separating positive and negative cages; and cross-foster (XF) rederivation. The test and separate approach was unsuccessful due to the animal housing and husbandry set up in the SPF barrier area given that MKPV is an environmentally stable and highly infectious agent. However, with an XF rederivation method, we were able to successfully rederive 11 out of 16 litters of various genetically modified lines that remained MKPV negative over a 20-week testing period. Our trial indicates that XF rederivation techniques, coupled with strict disinfection, can be used for a growing list of viral and other infectious agents that are highly infectious and persistent in the environment.