Pathogenesis and Immune Response of Ebinur Lake Virus: A Newly Identified Orthobunyavirus That Exhibited Strong Virulence in Mice.

Orthobunyaviruses are a group of viruses with significant public and veterinary health importance. These viruses are mainly transmitted through mosquito-, midge-, and tick-vectors, and are endemic to various regions of the world. Ebinur Lake virus (EBIV), a newly identified member of Orthobunyavirus, was isolated from Culex mosquitoes in Northwest China. In the present study, we aimed to characterize the pathogenesis and host immune responses of EBIV in BALB/c mice, as an animal model. Herein, we determined that BALB/c mice are highly susceptible to EBIV infection. The infected mice exhibited evident clinical signs including weight loss, mild encephalitis, and death. High mortality of mice was observed even with inoculation of one plaque-forming unit (PFU) of EBIV, and the infected mice succumbed to death within 5-9 days. After EBIV challenge, rapid viremic dissemination was detected in the peripheral tissues and the central nervous system, with prominent histopathologic changes observed in liver, spleen, thymus, and brain. Blood constituents' analysis of EBIV infected mice exhibited leukopenia, thrombocytopenia, and significantly elevated ALT, LDH-L, and CK. Further, EBIV infection induced obvious cytokines changes in serum, spleen, and brain in mice. Collectively, our data describe the first study that systematically examines the pathogenesis of EBIV and induced immune response in an immunocompetent standard mouse model, expanding our knowledge of this virus, which may pose a threat to One Health.

Isolation and identification of respiratory tract and intestinal microflora of Meriones meridianus in a conventional animal facility.

BACKGROUND: Culturable bacterial species from the respiratory tract and ileocecal junction of Meriones meridianus (midday gerbils) captured in the Xinjiang Luntai area were isolated and identified to confirm the microflora and develop approaches for biological purification of laboratory animals and relevant microbial precautions. METHODS: Bacteria from respiratory tracts and ileocecal junctions of 30 wild M. meridianus were harvested and isolated by inoculation into culture media. Isolated strains were confirmed by mass spectrometry and 16S rRNA sequencing. RESULTS: Thirty-nine bacterial species from 20 families and 27 genera were identified and isolated from wild M. meridianus. Typical bacteria were Enterobacteriaceae, Enterococcus, and Staphylococcus aureus, and the most common microflora were Vibrio, Staphylococcus aureus, and Pseudomonas aeruginosa. CONCLUSION: Wild M. meridianus carries multiple bacteria, most of which are pathogenic or conditional pathogens. This study provides a basis for the development of animal models and laboratory animals from wild M. meridianus.