一起禽肺病毒与H9亚型禽流感病毒混合感染的研究报道

A BRIEF REPORT OF MIXED INFECTION OF AVIAN METAPNEUMOVIRUS AND H9 SUBTYPE AVIAN INFLUENZA VIRUS

从山东省一起疑似禽肺病毒感染的病例中分离到1株H9亚型禽流感病毒(H9 subtype Avian influenza virus,AIV-H9),未分离到禽肺病毒(Avian metapneumovirus,APV),但血清学检测发现APV-ELISA抗体参差不齐。根据已公布的APV的G基因和AIV-H9的HA基因序列分别设计合成引物,进行RT-PCR扩增,结果得到大小为692 bp和1683 bp的目的条带;测序分析发现,该发病鸡场感染的APV(SD/RZ/15)G基因片段与Genbank中登录的B型APV核苷酸序列同源性最高(92.1%^-94.5%)且遗传距离最近,处于同一个分支。分离到的AIV-H9毒株(CK/SD/RZ/H9/15)的HA基因与参考毒株的核苷酸序列同源性为87.3%~98.9%,遗传进化关系分析表明该分离毒株与近几年分离的H9处于同一个分支上。综合上述试验结果,确定该病例为B型APV与AIV-H9的混合感染引起。

The H9subtype Avian influenza virus(AIV-H9)(CK/SD/RZ/H9/15)was isolated from a case infected by Avian metapneumovirus(APV)in Shandong.No APV was isolated and antibody was detected irregularly by ELISA.However,the cDNA fragments of692bp and1683bp were amplified using specific primers corresponding to G gene of APV and HA gene of AIV-H9in GenBank.The nucleotide sequences analysis showed that the APV shared more than92.1%-94.5%homology with B type APV in G gene,which suggested that APV might belong to B type APV.Furthermore,the AIV strain CK/SD/RZ/H9/15shared87.3%-98.9%homology with AIV-H9in view of HA gene,which suggested closer relationship between isolated viruses in recent years.In conclusion,the case was caused by mixed infection of APV and AIV-H9.