RESUMEN
H9N2 IAV infection contributed to P. aeruginosa coinfection, causing severe hemorrhagic pneumonia in mink. In this study, the in vitro alveolar macrophage models were developed to investigate the innate immune responses to P. aeruginosa LPS stimulation following H9N2 IAV infection, using MH-S cells. The cytokine levels, apoptosis levels and the viral nucleic acid levels were detected and analyzed. As a result, the levels of IFN-α, IL-1ß, TNF-α, and IL-10 in MH-S cells with P. aeruginosa LPS stimulation following H9N2 IAV infection were significantly higher than those in MH-S cells with single H9N2 IAV infection and single LPS stimulation (P < 0.05), exacerbating inflammatory responses. LPS stimulation aggravated the apoptosis of MH-S cells with H9N2 IAV infection. Interestingly, LPS stimulation influences H9N2 IAV replication and indirectly reduced H9N2 IAV replications in in vitro AMs. It implied that LPS should play an important role in the pathogenesis of H9N2 IAV and P. aeruginosa coinfection.
RESUMEN
In this study, whether H9N2 influenza A virus (IAV) infection contributed to secondary Klebsiella pneumoniae infection was investigated. From post-infection onwards, clinical symptoms were monitored, examined and recorded daily for 11 days. As a result, no clinical signs were observed in the mice infected with single H9N2 IAV, implying that H9N2 IAV was less pathogenic to mice. Compared to single K. pneumonia infection, K. pneumoniae infection following H9N2 IAV infection exacerbates lung histopathological lesions and apoptosis, resulting in more severe diseases. Lung index of the mice with H9N2 IAV and K. pneumoniae co-infection was significantly higher than those in the other groups. Bacterial loads in the tissues in H9N2 IAV and K. pneumoniae co-infection group were significantly higher than those in the single K. pneumoniae infection group at 7 dpi. It demonstrated that prior H9N2 IAV infection contributed to K. pneumonia proliferation and delayed bacterial clearance in mice. Secondary K. pneumoniae infection influences seroconversion of anti-H9N2 antibody titers and the cytokine profiles. The findings demonstrated that H9N2 IAV infection facilitated secondary K. pneumonia infection, causing severe the diseases in mice.
Asunto(s)
Subtipo H9N2 del Virus de la Influenza A , Klebsiella pneumoniae , Infecciones por Orthomyxoviridae , Neumonía , Animales , Coinfección , Subtipo H9N2 del Virus de la Influenza A/fisiología , Klebsiella pneumoniae/fisiología , Ratones , Infecciones por Orthomyxoviridae/microbiología , Infecciones por Orthomyxoviridae/virología , Neumonía/microbiología , Neumonía/virologíaRESUMEN
In this study, the infectious RF-DNA clones of two mink enteritis viruses, MEV-SD1 and MEV-SD7, were constructed, which generated progeny virions and seemed to contain an almost or completely full-length genome. The genomes of MEV-SD1 and MEV-SD7 were 5162 bp and 5113 bp in length, respectively. The genomic organizations of MEV-SD1 and MEV-SD7 were similar to that of the other carnivore parvoviruses. The 3'-UTR of the virion strand of MEV-SD1 and MEV-SD7 were 311 bp and 313 bp in length, respectively, containing a 208 bp palindromic sequence assuming Y-shaped configurations. Interestingly, the difference of the 3' palindromic sequences between MEV-SD1 and MEV-SD7 resulted in the orientation inversion of the hairpin ears. And the 5'-UTRs of MEV-SD1 and MEV-SD7 were 582 bp and 531 bp, respectively, containing a 198 bp palindromic sequence assuming U-shaped configurations, a triplet mismatch (5'-TAC-3') in the center of the duplex stem and a triplet mismatch (5'-AGA-3') forming a small asymmetric bubble. The findings demonstrated that the genomic termini of the carnivore parvoviruses showed the diversity in length, base composition, and predicted secondary structure.
Asunto(s)
Virus de la Enteritis del Visón , Regiones no Traducidas 5' , Animales , Secuencia de Bases , Células Clonales , ADN , Visón , Virus de la Enteritis del Visón/genética , SindactiliaRESUMEN
In this study, eight H9N2 IAVs were isolated from infected diseased, farmed raccoon dogs and arctic foxes. Eight genes shared 98.6%-100% identity among the isolates possessing a PSRSSR/GL motif at the HA cleavage site, which is same as the motif of G1 and Y280 lineages of H9N2 IAVs. The phylogenetic analysis showed that the HA genes of the eight isolates clustered with Y280-like viruses, whereas the NA genes belonged to F/98-like sublineage. Interestingly, the NS, NP, PB2 and PA genes of the isolates were closely related to H7N9 IAVs. This is the first evidence for isolation of H9N2 IAVs from raccoon dogs and arctic foxes. Raccoon dogs and arctic foxes potentially serve as an intermediate host for influenza viruses with pandemic potential toward other animals due to co-expression of both SA α-2,6-Gal and SA α-2,3-Gal receptors in a wide range of their tissues.
Asunto(s)
Zorros/virología , Subtipo H9N2 del Virus de la Influenza A/genética , Infecciones por Orthomyxoviridae/veterinaria , Perros Mapache/virología , Animales , China , Femenino , Subtipo H9N2 del Virus de la Influenza A/aislamiento & purificación , Masculino , Infecciones por Orthomyxoviridae/virología , FilogeniaRESUMEN
Influenza A virus (IAV) and bacteria co-infection can influence the host clinical conditions. Both H9N2 IAV and Pseudomonas aeruginosa (P. aeruginosa) are potential pathogens of respiratory diseases in mink. In this study, to clarify the effects of H9N2 IAV and P. aeruginosa co-infections on hemorrhagic pneumonia in mink, we carried out to establish the mink models of the two-pathogen co-infections in different orders. Compared with the single infections with H9N2 IAV or P. aeruginosa, the mink co-infected with H9N2 IAV and P. aeruginosa showed severe respiratory diseases, and exacerbated histopathological lesions and more obvious apoptosis in the lung tissues. H9N2 IAV shedding and viral loads in the lungs of the mink co-infected with H9N2 IAV and P. aeruginosa were higher than those in the mink with single H9N2 IAV infection. Furthermore, the clearance of P. aeruginosa in the co-infected mink lungs was delayed. In addition, the anti-H9N2 antibody titers in mink with P. aeruginosa co-infection following H9N2 IAV infection were significantly higher than those of the other groups. This implied that H9N2 IAV and P. aeruginosa co-infection contributed to the development of hemorrhagic pneumonia in mink, and that P. aeruginosa should play a major role in the disease. The exact interaction mechanism among H9N2 IAV, P. aeruginosa and the host needs to be further investigated.
Asunto(s)
Coinfección/veterinaria , Hemorragia/veterinaria , Subtipo H9N2 del Virus de la Influenza A/patogenicidad , Infecciones por Orthomyxoviridae/veterinaria , Neumonía/veterinaria , Infecciones por Pseudomonas/veterinaria , Pseudomonas aeruginosa/patogenicidad , Animales , Anticuerpos Antivirales/sangre , Coinfección/microbiología , Coinfección/virología , Hemorragia/microbiología , Hemorragia/virología , Humanos , Pulmón/patología , Pulmón/virología , Visón/microbiología , Visón/virología , Infecciones por Orthomyxoviridae/microbiología , Neumonía/microbiología , Neumonía/virología , Infecciones por Pseudomonas/virología , Replicación Viral , Esparcimiento de VirusRESUMEN
In this study, 20 P. aeruginosa strains were isolated from 112 farmed mink exhibiting hemorrhagic pneumonia in mideastern Shandong province, China. Serotype G (18/20) was the dominant serotype among the isolates with prevalence in mink, followed by serotype B (1/20), serotype C (1/20). The 9 virulence-associated genes of P. aeruginosa were tested using PCR. The prevalence of the virulence genes for the isolates were algD 95% (19/20), plcH 85% (17/20), exoY 80% (16/20), aprA 75% (15/20), lasB 70% (14/20), exoS 65% (13/20), exoT 60% (12/20) and toxA 60% (12/20), respectively. The 20 isolates were negative for exoU gene. The isolates exhibited multidrug resistance and cross resistance, using antimicrobial disc susceptibility assays. The animal experiments demonstrated that LD50% of the P.aeruginosa-CS-2 in the intratracheally challenged mink was 2.2 × 107.0 CFU, and 6.8 × 104.0 CFU in the intraperitoneally challenged mink. It implied that both the inoculation doses and the routes of inoculation could have influences on the pathogenicity of P. aeruginosa in mink. Therefore, the evolutionary and epidemiological surveillance of P. aeruginosa in mink should be further strengthened for public health.
Asunto(s)
Proteínas Bacterianas/genética , Visón/microbiología , Infecciones por Pseudomonas/veterinaria , Pseudomonas aeruginosa/aislamiento & purificación , Pseudomonas aeruginosa/patogenicidad , Factores de Virulencia/genética , Animales , Antibacterianos/farmacología , Proteínas Bacterianas/metabolismo , Técnicas de Tipificación Bacteriana , Farmacorresistencia Bacteriana Múltiple , Filogenia , Infecciones por Pseudomonas/microbiología , Pseudomonas aeruginosa/clasificación , Pseudomonas aeruginosa/genética , Factores de Virulencia/metabolismoRESUMEN
Three parvoviruses were isolated from the raccoon dogs experiencing severe enteritis, named RDPV-DP1, RDPV-DP2 and RDPV-DP3, respectively. The VP2 genes of the 3 isolates showed 99.9% identity at the nucleotide level, and shared 99.1%-99.5% identity with the reference CPVs. The RDPVs resembled original CPV-2, but with four mutations. The RDPVs displayed S297A of VP2 protein as CPV-2a or CPV-2b prevalent throughout most of the world. Residue N375D was found in the 3 isolates, resembling CPV-2a/2b/2c. And the 3 isolates had a natural mutation of VP2 residue V562L, which is adjacent to residue 564 and 568 and might be involved in host range. Interestingly, VP2 S27T was firstly found in the isolates. Phylogenetic analysis of VP2 genes revealed that the RDPVs were clustered into one small evolutionary branch and shared the identical branch with 7 CPV-2 isolates from raccoon dogs and one CPV-2 isolate from fox, not with CPV vaccine viruses. Phylogenetic analysis of NS1 genes demonstrated that the RDPVs shared the identical branch with the reference CPV-2a/2b/2c. Experimental infection showed that RDPV infection caused a high morbidity in raccoon dogs. It implied that the RDPV was virulent to raccoon dogs and continued to evolve in China.
Asunto(s)
Infecciones por Parvoviridae/veterinaria , Parvovirus Canino/genética , Parvovirus Canino/patogenicidad , Animales , Proteínas de la Cápside/genética , China/epidemiología , Enfermedades de los Perros/epidemiología , Enfermedades de los Perros/virología , Perros , Variación Genética , Especificidad del Huésped , Mutación , Infecciones por Parvoviridae/epidemiología , Infecciones por Parvoviridae/fisiopatología , Infecciones por Parvoviridae/virología , Parvovirus Canino/aislamiento & purificación , Filogenia , Perros Mapache , Análisis de Secuencia de ADNRESUMEN
In the study, 15 K. pneumoniae strains were isolated from the mink experiencing respiratory distress in mideastern Shandong province, China, and the prevalence of K. pneumoniae in the sampled mink was 11.9% (15/126). Fourteen (93.33%) of the 15 K. pneumoniae isolates were identified as serotype K2 and hypermucoviscosity phenotype. The 12 virulence-associated genes of the K. pneumoniae isolates were tested. The prevalence of the wabG gene for the isolates were 100% (15/15), the ureA gene 100% (15/15), the rmpA gene 93.33% (14/15), the aerobactin gene 93.33% (14/15), the uge gene 93.33% (14/15), the IucB gene 80% (12/15) and the ybtA gene 13.33% (2/15). But the other five genes, fim, iroNB, wcaG, alls and kfuBC, gave a negative PCR reaction in the 15 isolates, respectively. The animal experiments using K. pneumoniae-SD-12 and K. pneumoniae-SD-21 demonstrated that the serotype K2 was high virulence for mice and mink. These finding implied there exist potential threat that K. pneumoniae pathogens could transmit to human, especially the fur animal farm workers and residents lived near the fur animal farms. Therefore, the etiology and epidemiological surveillance of K. pneumoniae in mink should be strengthened for people's public health.
Asunto(s)
Proteínas Bacterianas/metabolismo , Infecciones por Klebsiella/epidemiología , Klebsiella pneumoniae/patogenicidad , Absceso Hepático/epidemiología , Trastornos Respiratorios/epidemiología , Serogrupo , Factores de Virulencia/metabolismo , Animales , Proteínas Bacterianas/genética , China/epidemiología , Incidencia , Infecciones por Klebsiella/genética , Infecciones por Klebsiella/virología , Absceso Hepático/genética , Absceso Hepático/virología , Ratones , Visón , Fenotipo , Trastornos Respiratorios/genética , Trastornos Respiratorios/virología , Factores de Virulencia/genéticaRESUMEN
H9N2 influenza A virus (IAV) causes low pathogenic respiratory disease and infects a wide range of hosts. In this study, six IAVs were isolated from mink and identified as H9N2 IAV. Sequence analysis revealed that the six isolates continued to evolve, and their PB2 genes shared high nucleotide sequence identity with H7N9 IAV. The six isolates contained an amino acid motif PSRSSR↓GL at the hemagglutinin cleavage site, which is a characteristic of low pathogenic influenza viruses. A serosurvey demonstrated that H9N2 IAV had spread widely in mink and was prevalent in foxes and raccoon dogs. Transmission experiments showed that close contact between H9N2-infected mink and naive mink, foxes and raccoon dogs resulted in spread of the virus to the contact animals. Furthermore, H9N2 challenge experiments in foxes and raccoon dogs showed that H9N2 IAV could infect these hosts. Virological and epidemiological surveillance of H9N2 IAV should be strengthened for the fur animal industry.
Asunto(s)
Transmisión de Enfermedad Infecciosa , Subtipo H9N2 del Virus de la Influenza A/crecimiento & desarrollo , Infecciones por Orthomyxoviridae/veterinaria , Secuencias de Aminoácidos/genética , Animales , Anticuerpos Antivirales/sangre , Zorros , Subtipo H9N2 del Virus de la Influenza A/clasificación , Subtipo H9N2 del Virus de la Influenza A/genética , Subtipo H9N2 del Virus de la Influenza A/aislamiento & purificación , Visón , Infecciones por Orthomyxoviridae/transmisión , Infecciones por Orthomyxoviridae/virología , ARN Polimerasa Dependiente del ARN/genética , Mapaches , Análisis de Secuencia de ADN , Estudios Seroepidemiológicos , Proteínas Virales/genéticaRESUMEN
Six feline panleukopenia viruses (FPV) were detected in the intestinal samples from the 176 mink collected in China during 2015 to 2016, named MEV-SD1, MEV-SD2, MEV-SD3, MEV-SD4, MEV-SD5 and MEV-SD6. The VP2 genes of the isolates shared 98.9%-100% identity with the reference sequences. The substitution of residue V300A in VP2 protein differentiates the isolates from the reference MEVs, and A300 is a characteristic of FPV. Furthermore, phylogenetic analysis of VP2 genes indicated that the six isolates were clustered into the same branch of all the reference FPVs. The NS1 genes of the isolates shared 98.2%-100% identity with the reference sequences. The NS1 genes of the six isolates and the three reference FPVs formed one unique evolutionary branch. To clarify the pathogenicity of the isolates, animal experiments were performed on healthy mink, using MEV-SD1. As a result, the morbidity of the inoculated animals was 100% and the mortality was as high as 38.9%. It was implied that the FPV infection caused a high morbidity and mortality in mink and the inoculation dose had an effect on pathogenicity of MEV-SD1 in mink.
Asunto(s)
Virus de la Panleucopenia Felina/clasificación , Panleucopenia Felina/virología , Animales , Gatos , China , Virus de la Panleucopenia Felina/genética , Virus de la Panleucopenia Felina/aislamiento & purificación , Virus de la Panleucopenia Felina/patogenicidad , Visón , FilogeniaRESUMEN
In mid-August 2013, two H9N2 influenza viruses, named A/mink/Shandong/F6/2013 (Mk/SD/F6/13) and A/mink/Shandong/F10/2013 (Mk/SD/F10/13), were isolated from lung samples of 2 of 45 farmed mink exhibiting respiratory signs in mideastern Shandong province, China. The seroprevalence of antibodies to H9N2 in mink was 20% (53/265). Based on sequence analysis, the eight nucleotide sequences showed 99.7-100% identity between Mk/SD/F6/13 and Mk/SD/F10/13. The HA, NP and NS genes of Mk/SD/F6/13 and Mk/SD/F10/13 were close to A/chicken/Zhejiang/329/2011 (H9N2), the NA and PB1 genes to A/duck/Hunan/S4111/2011 (H9N2), the PA and M genes to A/chicken/Shanghai/C1/2012 (H9N2). However, the PB2 genes had a close relationship with A/Turkey/California/189/66 (H9N2). Based on Sialic acid (SA) receptor detection, a range tissues of the mink demonstrated staining for MAA and/or SNA, and mink could serve as an intermediate host for influenza viruses with pandemic potential for the other animals. Experimental infection of mink demonstrated that mink could be infected by H9N2 influenza viruses and presented mild clinical signs, virus shedding and seroconversion, but no animals died of the disease. It implied that mammalian host-adapted avian H9N2 strains infected mink.
Asunto(s)
Subtipo H9N2 del Virus de la Influenza A/aislamiento & purificación , Visón/virología , Infecciones por Orthomyxoviridae/veterinaria , Animales , Secuencia de Bases , China/epidemiología , Femenino , Subtipo H9N2 del Virus de la Influenza A/genética , Pulmón/patología , Pulmón/virología , Masculino , Datos de Secuencia Molecular , Infecciones por Orthomyxoviridae/epidemiología , Infecciones por Orthomyxoviridae/patología , Análisis de Secuencia de ADN , Estudios Seroepidemiológicos , Proteínas Virales/genéticaRESUMEN
The novel H5N2 influenza virus, CA/SD/JT01/09, was isolated from the dog exhibiting respiratory signs in China in 2009. Dog to dog transmission of the novel H5N2 was previously confirmed. But interspecies transmission of the virus between dogs and the other animals has still remained unclear. To determine whether the virus can be transmitted directly from dogs to cats and chickens, we conducted contact exposure experiments. Susceptible cats and chickens were housed in the room which the novel H5N2 infected dogs were housed in, respectively. As a result, only one cat showed clear manifestations of H5N2 infection, but susceptibility of the other cats to H5N2 was confirmed by seroconversion. Eight of the exposure chickens showed clear manifestations of illness and 2 chickens died, and it demonstrates that chickens are susceptible to the recombinant H5N2. It implied that close contact between the H5N2-infected dogs and the cats and chickens resulted in spread of the virus to the sentinel animals.
Asunto(s)
Enfermedades de los Gatos/transmisión , Enfermedades de los Gatos/virología , Enfermedades de los Perros/virología , Especificidad del Huésped , Subtipo H5N2 del Virus de la Influenza A/fisiología , Infecciones por Orthomyxoviridae/veterinaria , Enfermedades de las Aves de Corral/virología , Animales , Enfermedades de los Gatos/patología , Gatos , Pollos , China , Susceptibilidad a Enfermedades , Enfermedades de los Perros/patología , Enfermedades de los Perros/transmisión , Perros , Infecciones por Orthomyxoviridae/patología , Infecciones por Orthomyxoviridae/transmisión , Infecciones por Orthomyxoviridae/virología , Enfermedades de las Aves de Corral/patología , Enfermedades de las Aves de Corral/transmisiónRESUMEN
To reveal the genetic variation of the viral protein 1 (VP1) gene of the duck hepatitis A virus type 3 (DHAV-3), the VP1 gene of 13 virulent DHAV-3 strains isolated from Shandong province of China in 2012 were amplified by RT-PCR, sequenced and analyzed. The results showed that all the VP1 genes of the 13 isolates contained 720 nucleotides encoding 240 amino acids, and shared with nucleotide identities of 94. 6%-99.9% and amino acid identities of 95.0%-100%. The nucleotide and amino acid sequence homologies between the 13 DHAV-3 isolates and other 31 DHAV-3 reference strains were 92.5%-100% and 90. 8%-100%, respectively. Phylogenetic analysis showed that the VP1 gene of DHAV-3 had distinct geographical characteristics. Distribution of genotypes of the 44 DHAV-3 strains was as follows: except the vaccine strain B63, all the other Chinese isolates belonged to genotype I (GI), Vietnamese wild isolates mainly belonged to subtype 1 (S1) of genotype II (GII), and all Korean isolates belonged to subtype 2 (S2) of GII.
Asunto(s)
Animales , Secuencia de Aminoácidos , Proteínas de la Cápside , Química , Genética , China , Patos , Virus de la Hepatitis del Pato , Clasificación , Genética , Hepatitis Viral Animal , Virología , Datos de Secuencia Molecular , Filogenia , Infecciones por Picornaviridae , Virología , Enfermedades de las Aves de Corral , VirologíaRESUMEN
In order to survey the infectious situation of canine coronavirus (CCV) in giant panda population, a virus neutralization test detecting specific antibodies against CCV in giant panda's sera was established by using two-fold dilutions of serum and 100 TCID50 of the virus. The 62 sera samples of giant pandas, which were gathered from zoos and reserve region of Sichuan Province, China were detected. The neutralization antibody titer of 1:4 was recognized as the positive criterion, 8 sera samples were detected to be positive, and the positive rate was 12.9%. The titers of neutralizing antibody ranged from 1:8 to 1:32. It was the first comprehensive investigation on neutralization antibodies against CCV in giant panda population in China. The results of study showed that the infection of CCV in giant panda population was universal, which has posed a threat to the health of giant panda. Therefore, it is incumbent on us to study safe and effective vaccines to protect giant panda against CCV infection.