2nd AFLAS Congress Report

The 2nd AFLAS (the Asian Federation of Laboratory Animal Science Associations) Congress in 2006 was held at the International Convention Center Jeju, Jeju in South Korea, from August 30 to September 1, 2006, with the attendance of more than 200 scientists from Asia and other areas such as North and South America and Europe. Ten symposia and one work shop were organized and 148 scientific posters were presented on this congress. From RIKEN BRC, Dr.Fumio Ike made an oral presentation on the symposium 10 (Infectious Diseases of Laboratory Animals) with the title of "Lymphocytic choriomeningitis virus (LCMV), emerging pathogen" which described the LCMV infection detected in wild-derived mice that were imported from France. Next AFLAS Congress will be held in Beijing, China, in 2008.

Lymphocytic choriomenintigis virus (LCMV), emerging pathogen

Fumio Ike and Atsushi Yoshiki RIKEN BioResource Center, Tsukuba, Ibaraki, 305-0074, Japan

The lymphocytic choriomeningitis virus (LCMV) is a prototypic member of the arenaviridae family. It is maintained in nature by lifelong persistence in wild mice, but transmissible to diverse mammalian hosts including humans and causative of opportunistic infection by direct contact with mouse secretions, in particular urine. Persistent LCMV infection in wild-derived mice housed under conventional circumstances for a decade was detected when rederivation of these mice was attempted by embryo transfer. Recipient mothers produced anti-LCMV antibodies which initially indicated the presence of the virus in the colony. In this colony, periodic health monitoring using dirty bedding sentinels was performed but LCMV had never been detected. Cesarian section rederivation also resulted in the vertical infection of LCMV because virus positive offspring were detected by immunofluorescence assay (IFA) and reverse transcriptase-polymerase chain reaction (RT-PCR) tests. The virus was isolated from infected kidneys and its pathogenicity was examined. Molecular analysis confirmed the isolated virus belonged to the LCMV group. Examination of animal technicians in contact with LCMV-infected mice, and of other mouse samples, by IFA and/or RT-PCR revealed that the LCMV had not contaminated the workers nor the animals in the facility. Experimental data showed that the LCMV transmission from persistently infected to healthy mice occurred only by direct contact in the same cage. This experience taught us the need for careful viral monitoring and the limitations of dirty bedding sentinel mice to detect LCMV infections.

The works described here were performed by the collaboration of the Institut Pasteur (Paris, France), Charles River Laboratories France (L'Arbresle, France), Nagasaki University (Nagasaki, Japan), National Institute of Infectious Diseases (Tokyo, Japan), ICLAS Monitoring Center, Central Institute for Experimental Animals (Kawasaki, Japan) and RIKEN BioResource Center (BRC). The RIKEN BRC collects, and preserves mouse resources as a core facility for the National Bio-Resource Project in Japan, and is supported by the Ministry of Education, Culture, Sports, Science and Technology.