RESUMEN
A canine influenza virus (CIV) strain of avian origin designated A/Canine/Jiangsu/06/2010 (H3N2) was isolated from dogs exhibiting severe respiratory disease in Jiangsu, China. We announce the complete genome sequence of this viral strain and report major findings from the genomic analysis. This sequence will help us understand the molecular characteristics and evolutionary of H3N2 CIV in China.
Asunto(s)
Enfermedades de los Perros/virología , Genoma Viral , Subtipo H3N2 del Virus de la Influenza A/genética , Infecciones por Orthomyxoviridae/veterinaria , Animales , Secuencia de Bases , China , Perros , Subtipo H3N2 del Virus de la Influenza A/aislamiento & purificación , Datos de Secuencia Molecular , Infecciones por Orthomyxoviridae/virología , ARN Viral/análisis , ARN Viral/genética , Análisis de Secuencia de ARNRESUMEN
BACKGROUND: Canine parvovirus (CPV) is an important pathogen that causes acute enteric disease in dogs. It has mutated and spread throughout the world in dog populations. We provide an update on the molecular characterization of CPV that circulated in Nanjing, a provincial capital in China between 2009 and 2012. RESULTS: Seventy rectal swab samples were collected from the dogs diagnosed with CPV infection in 8 animal hospitals of Nanjing. Sequence analysis of VP2 genes of 31 samples revealed that 29 viral strains belonged to CPV-2a subtype, while other two strains were classified into CPV-2b. To investigate the pathogenicity of the prevalent virus, we isolated CPV-2a and performed the animal experiment. Nine beagles were inoculated with 105.86 of 50% tissue culture infectious doses (TCID50) of the virus. All the experimentally infected beagles exhibited mild to moderate mucoid or watery diarrhea on day 4 post-infection (p.i.). On day 9 p.i., characteristic histopathological lesions were clearly observed in multiple organs of infected dogs, including liver, spleen, kidney, brain and all segments of the small and large intestines, while viral DNA and antigen staining could be detected in the sampled tissues. It is notable that canine parvovirus was isolated in one from two brain samples processed. CONCLUSION: Our results indicated that CPV-2a is the predominant subtype in Nanjing of China. And this virus caused extensive lesions in a variety of tissues, including the brain.
Asunto(s)
Enfermedades de los Perros/epidemiología , Enfermedades de los Perros/virología , Infecciones por Parvoviridae/veterinaria , Parvovirus Canino/aislamiento & purificación , Animales , China/epidemiología , ADN Viral/química , ADN Viral/genética , Perros , Genotipo , Epidemiología Molecular , Datos de Secuencia Molecular , Infecciones por Parvoviridae/epidemiología , Infecciones por Parvoviridae/virología , Parvovirus Canino/clasificación , Parvovirus Canino/genética , Recto/virología , Análisis de Secuencia de ADNRESUMEN
The newly emerging canine influenza virus (CIV) causes considerable concerns for both veterinary and public health. During 2009-2010, six strains of H3N2 influenza virus were isolated from dogs in Jiangsu Province, China. Sequence and phylogenetic analysis of eight gene segments revealed that the six viruses were most similar to a recent canine-derived subtype H3N2 influenza virus isolated in cats from South Korea, which originated from avian strain. By comparing the deduced amino acid sequences of the hemagglutinin 1 (HA1) and neuraminidase (NA) genes of the six Jiangsu isolates against the most similar avian strains, we found that all isolates had several common mutations at the receptor-binding sites, potential glycosylation sites and cleavage site in HA1, and antigenic sites in both the HA1 and NA segments. Significantly, a unique two amino acid insertion in the NA stalk was found. Experimental infection of BALB/c mice revealed that viral RNA could be detected in the major rodent organs, such as brain, heart, spleen, kidney, liver and intestine, as well as the lung. All the sampled organs from infected mice showed significant lesions and viral antigen staining. This study highlights the potential of domesticated animals to become a reservoir for influenza virus and the need for surveillance programs to detect cross-species transmission.