OBJECTIVETo analyze the genetic composition of a novel H2N3 virus isolate identified from a duck cage swab in a live poultry market (LPM) in 2009 in Guangdong province of China.

METHODSPCR-positive specimens were inoculated into embryonated chicken eggs and subtyped by conventional RT-PCR. All segments of the virus A/environment/Guangdong/2/2009 were sequenced, and phylogenetic trees were constructed and analyzed.

RESULTSThe genes of this virus belong to Eurasian-lineage avian viruses. The virus is a reassortant with the HA gene from an H2N2 virus and the NA gene from an H5N3 virus. The PB1, PB2, and NP genes were from an H4N6 virus, the PA was from an H3N8 virus, the M gene was from an H1N3 virus, and the NS gene was from an H10N6 virus.

CONCLUSIONA novel avian-origin reassortant H2N3 influenza virus was detected in a live poultry market. Its potential impacts and evolution should be closely monitored.

Animals ; China ; Ducks ; virology ; Genome, Viral ; Influenza A virus ; genetics ; isolation & purification ; Influenza in Birds ; virology ; Phylogeny

The propagation characteristics of virulent duck plague virus (DPV) in duck embryo fibroblast (DEF) were studied by the method of light microscopy observation of DEF cell culture monolayer, electron microscopy observation of infected DEF cell culture, real-time PCR detecting virus propagation. The results demonstrated that on duck embryo fibroblast a number of plaques were formed by DPV 42 h postinfection. Electron microscopy of the ultrathin section of infected duck embryo fibroblasts demonstrated that the nucleic acid of DPV was round in shape with diameter of 35-45 nm and was often in a cluster in the nucleus of DEF. The nucleocapsid of DPV was round in shape with diameter of 90-100 nm and could be observed both in nucleus and cytoplasm of DEF. The mature DPV which had the structures of envelop and tegument was spherical in shape with diameter of 150-300 nm and was located in cytoplasmic vacuoles. DPV penetrated the DEF cell membrane by direct fusion between the viral envelop and the plasma membrane. Progeny viral nucleic acid was produced in the nucleus and the assembled nucleocapsids obtained the structure of tegument in the cytoplasm and obtained the structure of envelop by budding into the cytoplasmic vesicles. The mature DPV particles were released out of the cell through exocytosis of the cytoplasmic vesicles. Detection of DPV by real-time PCR demonstrated that virus in DEF began its obvious propagation 10 h postinfection and virus amount tended to increase until 30 h postinfection. DPV began to be released into the supernatant 22 h postinfection and the DPV amount peaked 50 h postinfection, when the virus content in DEF and supernatant both underwent approximately 10(3) fold increase. DPV mainly existed in the DEF and the virus content in DEF was 10(2)-10(3) fold than the supernatant.
Animals ; Ducks ; embryology ; virology ; Fibroblasts ; virology ; Herpesviridae ; growth & development ; ultrastructure ; Microscopy, Electron ; Polymerase Chain Reaction

This article describes the nomenclature, history and genetic evolution of duck hepatitis A virus, and updates the epidemiology, clinical symptom and surveillances of duck virus hepatitis A. It also summarizes the present status and progress of duck virus hepatitis A and illustrated the necessity and urgency of its research, which provides rationale for the control of duck hepatitis A virus disease in China.
Animals ; Ducks ; virology ; Hepatitis Virus, Duck ; classification ; genetics ; isolation & purification ; Hepatitis, Viral, Animal ; virology ; Picornaviridae Infections ; veterinary ; virology

Replication of duck plague virus(DPV) in artificially infected ducks were detected by in situ hybridization (ISH) which employed a 37bp oligonucleotide as probe designed according to DPV DNA sequence in GenBank. The results indicated that DPV DNA was detected in liver, intestine and bursa Fabricius at 4 h, in spleen and esophagus at 6h, in thymus at 12h post infection; DPV DNA in lung and kidney was detected only in dead ducks and no positive signal was detected in muscle, heart, cerebrum and pancreas. DPV DNA was distributed in cell nucleus and cytoplasm. Hepatocytes, sinus endodermal cells and Kuffer's cells were the mainly infected cell types in liver. DPV DNA was mainly detected in epithelium of villi, in lamina propria of intestinal villi of duodenum, in stratum spinosum of esophagus, and in epithelium, cortex, medulla of bursa Fabricius. The positive signals were mainly detected in medulla of thymus, lymphocytes and macrophages of spleen. The research suggests that ISH is a direct and specific method in detecting DPV DNA in paraffin sections and it's also a good method for virus diagnosis and DNA location of DPV.
Animals ; DNA, Viral ; analysis ; Ducks ; virology ; In Situ Hybridization ; Influenza A virus ; genetics ; isolation & purification ; physiology ; Virus Replication

To clarify the pathogenesis of Duck enteritis virus (DEV), the cDNA library of duck's liver infected by DEV and a bait plasmid containing DEV nucleocapsid protein (NP) gene were constructed, then the receptor was screened from the cDNA library plasmid by the yeast two-hybrid system and verified by GST pull-down test. The results showed that the capacity of the primary cDNA library was 1 x 106 CFU with insertion size from 0.5 to 1 kb, and the bait plasmid of pGBKT7-NP showed no self-activation. The receptor reacting with DEV NP in duck liver was initially confirmed as the protein kinase C inhibitor (PKCI). These results provide new clues for further investigation on pathogenesis of DEV.
Alphaherpesvirinae ; pathogenicity ; Animals ; Ducks ; virology ; Gene Library ; Liver ; virology ; Nucleocapsid Proteins ; genetics ; Plasmids ; Receptors, Virus ; analysis ; Two-Hybrid System Techniques

The characteristics changes of apoptosis of Duck Embryo Fibroblasts (DEF) cells induced by New type gosling viral enteritis virus, NGVEV) were observed by means of HE staining, electron microscopy and Annexin V-FITC/PI fluorescent staining. During 24-48 h post infection (pi), the difference of morphological change between infected DEF cells and the mock infected cells was invisible. At 72 h pi, the nuclear chromatin was getting condensed through HE staining; apoptotic morphological change such as abnormal shape of the nucleus, condensation of the cytoplasm and chromatin were observed under electron microscope; and the early apoptotic cells (Annexin V-FITC positive and PI negative) were detected under fluorescence microscope. At 96-120 h pi, by means of HE staining and electron microscopy, the advanced morphological change of apoptosis such as formation of different kinds of apoptotic bodies, and shrink of the DEF cells and nucleus were detected; under fluorescence microscope the different stages of the apoptotic DEF can be easily distinguished: early apoptotic cells (Annexin V-FITC postive and pi negative), advanced or late apoptotic cells (both Annexin V-FITC and PI positive), necrosis cells or dead cells (Annexin V-FITC negative and PI positive). This investigation shows that NGVEV might induce apoptosis and form characteristic apoptotic morphological changes in the DEF cells. NGVEV inducement of apoptosis may be an important mechanism of efficient dissemination of virus progeny.
Adenoviridae ; physiology ; Animals ; Annexin A5 ; analysis ; Apoptosis ; Ducks ; embryology ; Enteritis ; veterinary ; virology ; Fibroblasts ; cytology ; virology ; Geese ; virology ; Microscopy, Electron, Transmission ; Poultry Diseases ; virology

OBJECTIVETo determine the molecular characterization of Polymerase complex (PA, PB1 and PB2) genes of H9N2 avian influenza viruses and the genetic relationship of Iranian H9N2 viruses and other Asian viruses.

METHODSThe Polymerase complex (PA, PB1 and PB2) genes from seven isolates of H9N2 viruses isolated from commercial chickens in Iran during 2008-2009 were amplified (by RT-PCR method) and sequenced. Nucleotide sequences (Open Reading Frame: orf) of the PA, PB1 and PB2 genes were used for phylogenetic tree construction.

RESULTSMost PB2 and PA genes of the H9N2 viruses isolated in 2008-2009 belonged to the unknown avian sublineage which grouped with the 2004 Pakistani H7N3 viruses. The PB1 genes of Iranian viruses indicated greater genetic diversity and shared a high level of similarity to PB1 genes from either H5 or H7 subtypes with compared to established H9N2 Eurasian sublineages.

CONCLUSIONSOur findings demonstrated that the H9N2 viruses in Iran exhibit striking reassortment which has led to the generation of new genotypes.

Animals ; Chickens ; virology ; Ducks ; virology ; Genotyping Techniques ; Influenza A Virus, H9N2 Subtype ; classification ; genetics ; Influenza in Birds ; virology ; Iran ; Pakistan ; RNA Replicase ; genetics ; Viral Proteins ; genetics

Avian leukosis virus subgroup J (ALV-J) is an avian retrovirus that can induce myelocytomas. A high-frequency mutation in gene envelope endows ALV-J with the potential for cross-species transmission. We wished to ascertain if the ALV-J can spread across species under selection pressure in susceptible and resistant hosts. First, we inoculated (in turn) two susceptible host birds (specific pathogen-free (SPF) chickens and turkeys). Then, we inoculated three resistant hosts (pheasants, quails and ducks) to detect the viral shedding, pathologic changes, and genetic evolution of different isolates. We found that pheasants and quails were infected under the selective pressure that accumulates stepwise in different hosts, and that ducks were not infected. Infection rates for SPF chickens and turkeys were 100% (16/16), whereas those for pheasants and quails were 37.5% (6/16) and 11.1% (3/27). Infected hosts showed immune tolerance, and inflammation and tissue damage could be seen in the liver, spleen, kidneys and cardiovascular system. Non-synonymous mutation and synonymous ratio (NS/S) analyses revealed the NS/S in hypervariable region (hr) 2 of pheasants and quails was 2.5. That finding suggested that mutation of isolates in pheasants and quails was induced by selective pressure from the resistant host, and that the hr2 region is a critical domain in cross-species transmission of ALV-J. Sequencing showed that ALV-J isolates from turkeys, pheasants and quails had moved away from the original virus, and were closer to the ALV-J prototype strain HPRS-103. However, the HPRS-103 strain cannot infect pheasants and quails, so further studies are needed.
Amino Acid Sequence ; Animals ; Avian Leukosis ; transmission ; virology ; Avian Leukosis Virus ; classification ; genetics ; physiology ; Chickens ; Ducks ; virology ; Galliformes ; virology ; Host Specificity ; Molecular Sequence Data ; Poultry Diseases ; transmission ; virology ; Quail ; virology ; Sequence Alignment ; Turkeys ; virology ; Viral Envelope Proteins ; chemistry ; genetics ; metabolism

Highly pathogenic avian influenza viruses (HPAIV) of the H5N1 subtype have spread since 2003 in poultry and wild birds in Asia, Europe and Africa. In Korea, the highly pathogenic H5N1 avian influenza outbreaks took place in 2003/2004, 2006/2007 and 2008. As the 2006/2007 isolates differ phylogenetically from the 2003/2004 isolates, we assessed the clinical responses of chickens, ducks and quails to intranasal inoculation of the 2006/2007 index case virus, A/chicken/Korea/IS/06. All the chickens and quails died on 3 days and 3-6 days post-inoculation (DPI), respectively, whilst the ducks only showed signs of mild depression. The uninoculated chickens and quails placed soon after with the inoculated flock died on 5.3 and 7.5 DPI, respectively. Both oropharyngeal and cloacal swabs were taken for all three species during various time intervals after inoculation. It was found that oropharyngeal swabs showed higher viral titers than in cloacal swabs applicable to all three avian species. The chickens and quails shed the virus until they died (up to 3 to 6 days after inoculation, respectively) whilst the ducks shed the virus on 2-4 DPI. The postmortem tissues collected from the chickens and quails on day 3 and days 4-5 and from clinically normal ducks that were euthanized on day 4 contained the virus. However, the ducks had significantly lower viral titers than the chickens or quails. Thus, the three avian species varied significantly in their clinical signs, mortality, tissue virus titers, and duration of virus shedding. Our observations suggest that duck and quail farms should be monitored particularly closely for the presence of HPAIV so that further virus transmission to other avian or mammalian hosts can be prevented.
Animals ; Antibodies, Viral/blood ; Brain/virology ; *Chickens ; *Coturnix ; *Ducks ; Heart/virology ; Influenza A Virus, H5N1 Subtype/*pathogenicity ; Influenza in Birds/epidemiology/transmission/*virology ; Kidney/virology ; Korea/epidemiology ; Lung/virology ; Virus Shedding

OBJECTIVETo discuss the possibility of hepatitis B virus (HBV) transmission through dental handpieces.

METHODSInvestigation was carried on methods for disinfecting and sterilizing dental handpieces and the condition of HBsAg contamination on dental handpieces before and after disinfection and sterilization by randomly sampling all special stomatological hospitals and dental clinics in a same city and 10 dental departments from the third, second and first class hospitals. The possibility of HBV transmission through dental handpieces was probed by investigating whether ducks can be infected by bath liquid of dental handpieces contaminated by DHBV, while in such bath liquid, DHBV can not be detected by serum dot hybridization.

RESULTSFrom 2001 to 2004, in methods to disposing dental handpieces, the use of autoclave was remarkably increased while of the disinfectant wipe, immersion and other methods was remarkably decreased. The positive rate of HBsAg from dental handpieces in practice was 1.65%. It was evident that the bath liquid of dental handpieces contaminated by DHBV can conduct infection in vivo test of duck, while DHBV can not be detected in such bath liquid by serum dot hybridization, it is proved that the negative result of HBsAg in non-sterilized dental handpieces can not eliminate the possibility of HBV transmission through dental handpieces.

CONCLUSIONThere might exist the possibility of HBV transmission through dental handpieces however, the autoclaves might kill the virus contaminating on dental handpieces.

Animals ; DNA, Viral ; blood ; Dental Instruments ; virology ; Ducks ; virology ; Equipment Contamination ; Hepatitis B ; transmission ; Hepatitis B Virus, Duck ; genetics ; isolation & purification ; Sterilization ; methods ; standards