FULL PAPER Epizootiological survey ofhantavirus among rodent species in Ningxia Hui Autonomous Province, China

Hantaviral antibodies were detected in the sera from Apodemus (A.) agrarius and A. peninsulae captured in Ningxia province, China by several different serological diagnostic methods. A total of 409 sera from rodent and insectivore species were collected in 1999 and examined by indirect immunofluorescent antibody assay (IFA). Among them, 19 of 191 (9.9%) sera of A. agrarius and 1 of 13 (7. 7 %) sera of A. peninsulae were positive for hantaviral antibodies. The other species (Rattus norvegicus, Mus musculus, Cricetulus triton, and Sorex cylindricauda) were negative. The reaction pattern of positive serum was characterized as scattered and granular virus antigens in the cytoplasm of hantavirus infected Vero E6 cells. Some of the A. agrarius sera positive for hantavirus were further examined by Western blotting (WB) , enzyme-linked immunosorbent assay (ELISA), and the focus reduction neutralization test (FRNT). By WB, positive sera showed the same specific reaction pattern of baculovirus-expressed recombinant hantaviral nucleocapsid protein, as shown in hantavirus-immune serum. By ELISA, IFApositive sera showed significantly higher optical densities (around 1. 0) than the negative A. agrarius sera. Hantaan type hantavirus was neutralized with the positive sera. These results suggest that A. agrarius have hantavirus in1 Laboratory of Public Health, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, 0600818, Japan Qinghai Institute for Epidemic Disease Control and Research, Xining 811602, China 3 Institute of Animal Experimentation, School of Medicine, Hokkaido University, Sapporo 060-8638, Japan 4 Shimane Prefectural Institute of Public Health and Environmental Science, Matsue 690-0122, Japan 5 Sanitation and Antiepidemic Station of Ningxia, Ningxia, China *Corresponding author: Hiroaki Kariwa, D. V. M., Ph. D Graduate School of Veterinary Medicine, Hokkaido University, Kita-18 Nishi-9, Kita-ku, Sapporo, Hokkaido 060-0818, Japan. Fax: +81-1-11-706-5212, E-mail: [email protected] 106 Hantavirus infection among rodents in China fection and may playa role as a reservoir animal for hantavirus in Ningxia H ui Autonomous Province, China.