The ferret is an established animal model of influenza virus infection. Although viral replication in the upper respiratory tract is usually measured with consecutively collected nasal washes, daily evaluation of viral replication in the lung is limited because a large numbers of ferrets need to be sacrificed at consecutive time points. To overcome this limitation, we performed a virus quantification assay using bronchoalveolar lavage (BAL) fluid. This non-invasive BAL technique allows consecutive quantification of virus replication in the lungs of living ferrets. Our method can be used for the longitudinal evaluation of virus tropism in the lower respiratory tract.
Animals ; Bronchoalveolar Lavage/*veterinary ; Disease Models, Animal ; Female ; Ferrets/*virology ; Influenza A Virus, H3N2 Subtype/*physiology ; Orthomyxoviridae Infections/*veterinary/virology ; Respiratory System/*virology ; Virus Replication/*physiology

Chinese ferret badger (FB)-transmitted rabies is a serious threat to public health in southeast China. Although mostly associated with dogs, the rabies virus (RABV) presents genetic diversity and has a significantly wide host range in China. Instead of the dog- and wildlife-associated China II lineage in the past decades, the China I lineage has become the main epidemic group hosted and transmitted by dogs. In this study, four new lineages, including 43 RABVs from FBs, have been classified within the dog-dominated China I lineage since 2014. FB RABVs have been previously categorized in the China II lineage. Moreover, FB-hosted viruses seem to have become the main independent FB-associated clade in the phylogenetic tree. This claim suggests that the increasing genetic diversity of RABVs in FBs is a result of the selective pressure from coexisting dog rabies. FB transmission has become complicated and serious with the coexistence of dog rabies. Therefore, apart from targeting FB rabies, priority should be provided by the appropriate state agencies to perform mass immunization of dog against rabies.
Animals ; Brain ; virology ; China ; epidemiology ; Disease Reservoirs ; veterinary ; virology ; Dog Diseases ; epidemiology ; transmission ; virology ; Dogs ; Ferrets ; virology ; Genetic Linkage ; Genetic Variation ; Phylogeny ; Phylogeography ; Rabies ; epidemiology ; transmission ; veterinary ; virology ; Rabies virus ; genetics

Based on sequencing the full-length genomes of four Chinese Ferret-Badger and dog, we analyze the properties of rabies viruses genetic variation in molecular level, get the information about rabies viruses prevalence and variation in Zhejiang, and enrich the genome database of rabies viruses street strains isolated from China. Rabies viruses in suckling mice were isolated, overlapped fragments were amplified by RT-PCR and full-length genomes were assembled to analyze the nucleotide and deduced protein similarities and phylogenetic analyses from Chinese Ferret-Badger, dog, sika deer, vole, used vaccine strain were determined. The four full-length genomes were sequenced completely and had the same genetic structure with the length of 11, 923 nts or 11, 925 nts including 58 nts-Leader, 1353 nts-NP, 894 nts-PP, 609 nts-MP, 1575 nts-GP, 6386 nts-LP, and 2, 5, 5 nts- intergenic regions(IGRs), 423 nts-Pseudogene-like sequence (psi), 70 nts-Trailer. The four full-length genomes were in accordance with the properties of Rhabdoviridae Lyssa virus by BLAST and multi-sequence alignment. The nucleotide and amino acid sequences among Chinese strains had the highest similarity, especially among animals of the same species. Of the four full-length genomes, the similarity in amino acid level was dramatically higher than that in nucleotide level, so the nucleotide mutations happened in these four genomes were most synonymous mutations. Compared with the reference rabies viruses, the lengths of the five protein coding regions had no change, no recombination, only with a few point mutations. It was evident that the five proteins appeared to be stable. The variation sites and types of the four genomes were similar to the reference vaccine or street strains. And the four strains were genotype 1 according to the multi-sequence and phylogenetic analyses, which possessed the distinct district characteristics of China. Therefore, these four rabies viruses are likely to be street viruses already existing in the natural world.
Animals ; China ; Deer ; Disease Reservoirs ; virology ; Dogs ; virology ; Ferrets ; virology ; Genome, Viral ; Humans ; Mice ; Molecular Sequence Data ; Phylogeny ; Rabies ; virology ; Rabies virus ; chemistry ; classification ; genetics ; isolation & purification ; Sequence Analysis, DNA ; Sequence Homology, Amino Acid ; Viral Proteins ; chemistry ; genetics