RESUMO
Outbreaks of highly pathogenic avian influenza (HPAI) have been reported worldwide. Wild waterfowl play a major role in the maintenance and transmission of HPAI. Highly pathogenic avian influenza subtype H5N6 and H5N8 viruses simultaneously emerged in South Korea. In this study, the comparative pathogenicity and infectivity of Clade 2.3.4.4 Group B H5N8 and Group C H5N6 viruses were evaluated in Mandarin duck (Aix galericulata). None of the ducks infected with H5N6 or H5N8 viruses showed clinical signs or mortality. Serological assays revealed that the HA antigenicity of H5N8 and H5N6 viruses was similar to each other. Moreover, both the viruses did not replicate after cross-challenging with H5N8 and H5N6 viruses, respectively, as the second infection. Although both the viruses replicated in most of the internal organs of the ducks, viral replication and shedding through cloaca were higher in H5N8-infected ducks than in H5N6-infected ducks. The findings of this study provide preliminary information to help estimate the risks involved in further evolution and dissemination of Clade 2.3.4.4 HPAI viruses among wild birds.
Assuntos
Patos/virologia , Vírus da Influenza A Subtipo H5N8/patogenicidade , Vírus da Influenza A/patogenicidade , Influenza Aviária/virologia , Doenças das Aves Domésticas/virologia , Animais , Anticorpos Antivirais/sangue , Vírus da Influenza A Subtipo H5N8/genética , Vírus da Influenza A Subtipo H5N8/imunologia , Vírus da Influenza A/classificação , Vírus da Influenza A/genética , Vírus da Influenza A/imunologia , Influenza Aviária/epidemiologia , Filogenia , Doenças das Aves Domésticas/epidemiologia , RNA Viral/genética , Reação em Cadeia da Polimerase em Tempo Real/veterinária , República da Coreia/epidemiologia , Soroconversão , Replicação Viral , Eliminação de Partículas ViraisRESUMO
The Peach rosette mosaic virus (PRMV) is a plant pathogen of the genus Nepovirus, and has been designated as a controlled quarantine virus in Korea. In this study, a specific reverse transcription (RT)-PCR marker set, nested PCR marker set, and modified-plasmid positive control were developed to promptly and accurately diagnose PRMV at plant-quarantine sites. The final selected PRMV-specific RT-PCR marker was PRMV-N10/C70 (967 bp), and the nested PCR product of 419 bp was finally amplified. The modified-plasmid positive control, in which the SalI restriction-enzyme region (GTCGAC) was inserted, verified PRMV contamination in a comparison with the control, enabling a more accurate diagnosis. It is expected that the developed method will continuously contribute to the plant-quarantine process in Korea.
RESUMO
Epidemiological and virological studies indicate that noroviruses-contaminated groundwater was the primary source of four acute gastroenteritis outbreaks in South Korea between 2008 and 2012. Furthermore, cabbage kimchi was first identified as the vehicle of transmission between groundwater and infected patients in an outbreak in 2011. The proper treatment of groundwater sources prior to use for drinking or in food preparation is necessary to prevent further outbreaks.
