National Agriculture and Food Research Organization (NARO) has conducted genetic analysis on 60 cases of high pathogenicity avian influenza virus (HPAIV) identified in domestic poultry facilities from October 28, 2022 to January 17, 2023. From the analysis result it was revealed that in 2022 season, there were three groups classified by the characteristics of the hemagglutinin (HA) gene invaded Japan at the same period and in a wide range from the earliest time so far. Two of these groups are closely related to groups detected in Japan last season, and one newly detected group is closely related to viruses isolated in West Siberia and Central China in 2021. Since this season has the highest number of outbreaks ever it is necessary to continue to monitor the trend of the HPAIV epidemic and be vigilant against the invasion of the virus into Japan and farms. Read more
National Agriculture and Food Research Organization (NARO) has developed the world's first method for rationally designing live vaccines in a short period of time. Using Erysipelothrix rhusiopathiae as a model, we estimated the genes involved in pathogenicity from the genomic information, and by deleting the genes, the bacteria was rationally attenuated. It is expected that this method can save labor in the development of live bacterial vaccines, which has been very costly and time-consuming. Read more
On September 25, 2022, highly pathogenic avian influenza virus (HPAIV) was detected in a peregrine falcon that died after weakening in Isehara City, Kanagawa Prefecture. The National Agriculture and Food Research Organization (NARO) has conducted whole-genome sequencing of this virus. From this analysis, it was revealed that this virus is closely related to the H5N1 HPAIV that caused outbreaks in Japan in the 2021/2022 season (autumn 2021 to spring 2022). HPAIV infection cases were confirmed in wild birds in Japan at the earliest time of the season since 2004, and HPAI outbreaks were also reported in domestic poultry in late October this year. Therefore, an increased alert is required to prevent the introduction of virus to poultry farms. Read more
National Agriculture and Food Research Organization (NARO) has conducted genetic and pathogenicity analysis of H5 highly pathogenic avian influenza virus (HPAIV) identified in domestic poultry farms from November 10, 2021, to May 14, 2022. From the analysis result it was revealed that there were two subtypes of the virus such as H5N8 subtype (2 cases) & H5N1 subtype (23 cases), and three groups of viruses entered the country during the same period based on the characteristics of the hemagglutinin (HA) gene in the 2021 season. Representative viruses from these groups all showed high lethality to chickens, but their infectivity and transmissibility differed between groups. Read more
Marek's disease causes tumors in poultry such as chickens and quails, which results in significant economic loss to the poultry industry. Since it is difficult to distinguish this disease from similar diseases, an accurate and simple diagnostic method was required for disease prevention measures. The National Agriculture and Food Research Organization(NARO) has succeeded in producing monoclonal antibodies that specifically detects Marek's disease tumor cells and established a new diagnostic method for Marek's disease by immunohistochemistry using the antibodies. It is expected that this research result will enable accurate and easy definitive diagnosis of Marek's disease, which has been technically difficult until now, and useful for grasping the accurate outbreak situation of Marek's disease and for disease prevention measures. Read more
National Agriculture and Food Research Organization (NARO) has performed genetic analysis of the classical swine fever virus (CSFV) obtained from the wild boar in Yamaguchi Prefecture, which was confirmed positive in March 2022. It was revealed that it is most closely related to the virus obtained from the wild boar in the eastern part of the Kii Peninsula, about 500 km away from Yamaguchi Prefecture, whose infection was confirmed in May 2021. This result indicates the need for countermeasures against long-distance transmission of the virus. Read more
