上海市某腹泻猪群猪流行性腹泻病毒检测及全基因序列分析

Detection and Complete Genomic Sequence Analysis of Porcine Epidemic Diarrhea Virus from a Diarrheal Pig Herd in

猪流行性腹泻(PED)是由猪流行性腹泻病毒(PEDV)感染引起的仔猪严重腹泻性疾病,传播快,发病急,死亡率高,给我国养猪业造成巨大损失。2021年10月上海某猪场产房仔猪发生腹泻,发病率为30%~50%,死亡率为20%~30%,猪群之前进行过疫苗免疫。粪便样本经猪流行性腹泻病毒、猪传染性胃肠炎病毒(TGEV)、猪轮状病毒(RV)荧光RT-PCR检测,结果显示:PEDV检测为阳性,TGEV和RV检测均为阴性。经全基因测序后进行系统进化分析,结果显示:全基因序列属于GⅡ-c亚群,S基因序列属于GⅡ-b亚群,与目前的经典疫苗株CV777和变异株AJ1102相比,CV777的全基因和S基因都属于GⅠ-b群,AJ1102的全基因和S基因都属于GⅡ-b亚群,研究结果表明新基因型的PEDV已在上海地区流行,而传统疫苗株无法提供好的免疫效果,提示新的防控策略的制定和有针对性的疫苗的生产和使用,对于预防PEDV感染和流行有重要意义。

Porcine epidemic diarrhea(PED)is a serious diarrheal disease of piglets caused by Porcine epidemic diarrhea virus(PEDV)infection.In October 2021,diarrhea occurred in piglets in the delivery room of a pig farm in Shanghai with the incidence rate of 30%-50%and mortality rate of 20%-30%.The pig herds had been vaccinated before.Fecal samples were examined by real-time RT-PCR for Porcine epidemic diarrhea virus,Transmissible gastroenteritis virus(TGEV),and Porcine rotavirus(RV).The results showed positive for PEDV and negative for TGEV and RV.Phylogenetic analysis of the whole genomic sequence showed that it belonged to the GII-c subgroup and the S gene sequence belonged to the GII-b subgroup.As a comparison,the whole genome and S gene of CV777 belonged to the GI-a subgroup,and the whole genome and S gene of AJ1102 belonged to the GII-b subgroup.These results showed that a new genotype of PEDV had been prevalent in Shanghai and commercial vaccine strains did not provide complete protection due to genetic variation.