No abstract available.
Animals ; Influenza in Birds*

No abstract available.
Animals ; Influenza in Birds*

No abstract available.
Animals ; Influenza in Birds*

Animals ; Birds ; Influenza A Virus, H5N1 Subtype ; Influenza in Birds ; virology

At the end of 2003 and early 2004, an epidemic of avian influenza with 10 cases and 7 deaths occurred in the North of Vietnam, a subtype H5N1 (A/H5N1) has been identified. The prevalence of total infection with epidemic syndrome in the whole area at the same time was 0.1%, the prevalence infected cases of death was very high (70%). The epidemic was widely distributed in 7 provinces and the highest number of cases was observed in the forth week by the onset of the first case. Sick hens were the evidence of causes. There was not direct infection from human to human. However, there were two case-clusters that happened in the same family, this may be a suggestion of biological and familial factors associated with the susceptibility to the causal virus A/H5N1
Epidemiology ; Influenza A Virus ; H5N1 Subtype ; Influenza in Birds

Study on clinical features and epidemiology among 10 patients had avian influenza A who treated in hospital in Ho Chi Minh City and Ha Noi 12/2003 and 1/2004, 13,7 mean age. In all patients, the diagnosis of influenza A (H5N1) was confirmed by means of viral culture or reverse transcriptase polymerase chain reaction (RT-PCR) with primers specific for H5 and N1. None of the 10 patients had pre-existing medical conditions. Nine patients had a clear history of direct contact with poultry. All patients had fever, respiratory symptoms and clinically significant lymphopenia. The medium platelet count was 75.500/mm3. Seven patients had diarrhea. In all patients, there were marked abnormalities on chest radiography. There was no definitive evidence of human to human transmission, eight patients died
Influenza A Virus, H5N1 Subtype ; Influenza in Birds ; epidemiology

Asian-lineage H5 highly pathogenic avian influenza (HPAI) viruses have caused continuous outbreaks in poultry and wild birds. Development of rapid and accurate diagnostic methods is needed for preventing further spread of the virus and reducing the time required for eradication of the virus. We developed a low-density microarray for the rapid detection and identification of avian influenza virus subtypes H5, H7, and H9 and their pathotypes in a previous study. In the present study, we evaluated previously developed diagnostic microarray using avian influenza viruses isolated in Mongolia, including H5 HPAI viruses. All H5 HPAI viruses isolated in Mongolia were shown as H5-specific and highly pathogenic pattern in the microarray. H2, H3 and H12 viruses isolated in Mongolia used in this study did not show any H5, H7 and H9 patterns. These results indicated that this diagnostic microarray has enormous potential for the rapid subtyping and pathotyping of influenza viruses, including viruses isolated in Mongolia.
Animals ; Birds ; Disease Outbreaks ; Influenza in Birds* ; Mongolia* ; Orthomyxoviridae ; Poultry

Korea is located within the East Asian-Australian flyway of wild migratory birds during the fall and winter seasons. Consequently, the likelihood of introduction of numerous subtypes and pathotypes of the Avian influenza (AI) virus to Korea has been thought to be very high. In the current study, we surveyed wild bird feces for the presence of AI virus that had been introduced to Korea between September 2017 and February 2018. To identify and characterize the AI virus, we employed commonly used methods, namely, virus isolation (VI) via egg inoculation, real-time reverse transcription-polymerase chain reaction (rRT-PCR), conventional RT-PCR (cRT-PCR) and a newly developed next generation sequencing (NGS) approach. In this study, 124 out of 11,145 fresh samples of wild migratory birds tested were rRT-PCR positive; only 52.0% of VI positive samples were determined as positive by rRT-PCR from fecal supernatant. Fifty AI virus specimens were isolated from fresh fecal samples and typed. The cRT-PCR subtyping results mostly coincided with the NGS results, although NGS detected the presence of 11 HA genes and four NA genes that were not detected by cRT-PCR. NGS analysis confirmed that 12% of the identified viruses were mixed-subtypes which were not detected by cRT-PCR. Prevention of the occurrence of AI virus requires a workflow for rapid and accurate virus detection and verification. However, conventional methods of detection have some limitations. Therefore, different methods should be combined for optimal surveillance, and further studies are needed in aspect of the introduction and application of new methods such as NGS.
Animals ; Birds ; Feces ; Influenza in Birds ; Korea ; Methods ; Ovum ; Seasons

In Taiwan, the first human-infecting H6N1 avian influenza virus was isolated in 2013. To better understand the origin, evolutionary relationship and pathogenesis of the H6N1 virus, we studied the adaptive evolution and evolutionary dynamics of the hemagglutinin (HA) genes of the H6N1 virus in Taiwan. We felt that such studies woud contribute to the further study and control of the virus. Datasets were gained from the Flu and Global Initiative on Sharing All Influenza Data (GISAID) databases. Then, phylogenetic trees and evolutionary dynamics were reconstructed. The evolutionary rate and characterization of adaptive evolution were analyzed by bioinformatic methods. Results indicated that the HA genes of H6N1 in Taiwan were divided into at least five types, and that the new types that the infected human H6N1 belonged to could be local advantage type at present. Evolutionary dynamics revealed the viral population expanded first at the end of 1971, reduced sharply in 2008, and then increased slightly. Three sites were identified under positive selection, suggesting that various sites might increase the adaptive ability of the virus. Eighty-nine sites were under negative selection, revealing that these sites might play an important role in the replication and epidemiology of the virus. Interestingly, site 329 upstream from the cleavage site was also under negative selection, suggesting that this site might be associated with the virulence of H6N1. These data suggest that the HA genes of the Taiwanese H6N1 virus have been undergoing adaptive evolution, and that an outbreak may occur again. Hence, more attention should be paid to the identified sites, to enable timely monitoring and control of a future epidemic.
Animals ; Birds ; Evolution, Molecular ; Hemagglutinin Glycoproteins, Influenza Virus ; genetics ; Influenza A virus ; genetics ; Influenza in Birds ; virology ; Taiwan

OBJECTIVETo assess the risk of local outbreaks of H7N9 avian influenza infection in Zhejiang province and to explore the semi-quantitative assessment method for public health risks in emergency.

METHODSRisk index system of human infection with H7N9 avian influenza caused by local transmission were reviewed. The weights of indexes were calculated by analytic hierarchy process, which was combined with the TOPSIS method to calculate the risk comprehensive index.

RESULTSFour primary indexes and 23 secondary indexes were identified for risk assessment in local outbreaks of H7N9 avian influenza infection. The weights ranked on the top five were:morbidity (0.0972), closure measures (0.0718), sterilization measures (0.0673), fatality rate (0.0651), and epidemic spread (0.0616). The comprehensive index of the risk of local outbreaks of H7N9 avian influenza ranged from high to low were Hangzhou (0.5910), Shaoxing (0.5711), Jiaxing (0.5199), Taizhou (0.5198), Huzhou (0.4662), Ningbo (0.3828), Wenzhou (0.3719), Jinhua (0.3392), Lishui (0.2727), Quzhou (0.2001) and Zhoushan (0.0508).

CONCLUSIONSA semi-quantitative method has been established in this study, which provides scientific basis for prevention and control of H7N9 avian influenza epidemic in Zhejiang province.

Animals ; Birds ; China ; Humans ; Influenza A Virus, H7N9 Subtype ; Influenza in Birds ; transmission ; Influenza, Human ; transmission ; Risk Assessment