The peak period of morbidity and death in cultured Procambarus clarkii is around May each year and is called the “Black May” disease. The pathogen causing “Black May” disease is believed to be a white spot syndrome virus (WSSV). In 2018, a significant number of P. clarkii died in the pond culture of Xinglong Township, Xuyi County. Two sampling tests on the affected pond showed that, in addition to WSSV, a novel Dicistro‐like virus (PcDV) was present. Genomic sequence analysis indicated that this new virus belongs to the Dicistroviridae family, Picornaviridaes order. A high number of spherical particles were detected in gill tissues of P. clarkii with “Black May” disease by electron microscopy, a finding consistent with viruses from the Picornaviridaes order. From October 2018 to September 2019, we took monthly samples from Hubei, Jiangsu and Anhui provinces, and tested for the presence of PcDV and WSSV in P. clarkii. The detection rates of PcDV in P. clarkii peaked from April to June, consistent with the onset of the “Black May” disease. In conclusion, we believe that the discovery of PcDV will provide new research directions for investigating the pathogens causing “Black May” disease in P. clarkii.

中文翻译：

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在克氏原螯虾中发现的一种新的类似Dicistro的病毒，伴有“ Black May”病

养殖的克氏原螯虾的发病率和死亡高峰期在每年的五月左右，被称为“黑五月”病。导致“黑五月”疾病的病原体被认为是白斑综合症病毒（WSSV）。在2018年，Xu邑县兴隆乡的池塘养殖中有大量的克拉克疟原虫死亡。在受影响的池塘上进行的两次抽样测试表明，除了WSSV外，还存在一种新型的Dicistro样病毒（PcDV）。基因组序列分析表明，该新病毒属于双顺反病毒科（Picornaviridaes）。在克氏假单胞菌的ill组织中检测到大量球形颗粒电镜检查发现“黑色五月”疾病，与小核糖核酸病毒科的病毒相符。从2018 10至9月2019年，我们把每月的样本来自湖北，江苏，安徽等省，以及的PCDV的存在和WSSV在测试的克氏原螯。克拉克假单胞菌中PcDV的检出率在4月至6月达到峰值，与“黑色五月”疾病的发作相一致。总之，我们认为的PCDV的发现将为研究导致“黑色五月”病病原体提供了新的研究方向克氏原螯。