Departamento de Medicina y Zootecnia de Cerdos, Facultad de Medicina Veterinaria y Zootecnia (FMVZ), Universidad Nacional Autónoma de México (UNAM), Mexico City, Mexico.
Laboratorio de Virología, Facultad de Estudios Superiores Cuautitlán (FESC), UNAM, Cuautitlan Izcalli, Mexico.
Transbound Emerg Dis. 2020 Mar;67(2):1035-1041. doi: 10.1111/tbed.13426. Epub 2019 Dec 16.
As an emerging disease, the porcine epidemic diarrhoea virus has caused substantial economic losses to the pork industry in Mexico, leading to piglet mortality rates of up to 100%. For detection, sequencing and genetic characterization of the virus, 68 samples of one-week-old piglets from pork farms in 17 states of Mexico were analysed. In total, 53 samples were positive by real-time RT-PCR, confirming the presence of the virus in 15 states. Twenty-eight samples from 10 states were amplified by endpoint RT-PCR, and 20 sequences of the spike gene were obtained. A phylogenetic analysis based on the spike gene demonstrated that all Mexican strains are in Group II and are classified as non-Indel-S emerging variants. Three strains showed amino acid insertions: PEDv/MEX/GTO/LI-DMZC15/2015 and PEDv/MEX/QRO/LI-DMZC45/2016 showed one amino acid insertion ( Y and D , respectively), and PEDv/MEX/QRO/LI-DMZC49/2019 showed one and two amino acid insertions ( C and SQ ), with the second insertion in the COE region. These results provide evidence of the prevalence of emerging, non-Indel-S strains of the virus are currently circulating in Mexico during 2016-2018, when three of which have amino acid insertions: PEDv/MEX/GTO/IN-DMZC15/2015 and PEDv/MEX/QRO/IN-DMZC45/2016 have one amino acid insertion each ( Y and D , respectively), and PEDv/MEX/QRO/IN-DMZC49/2019 has one ( C ) and two amino acid insertions ( SQ ), the latter being in the COE region, which could generate new antigenic variants.
作为一种新兴疾病，猪流行性腹泻病毒已给墨西哥的猪肉产业造成巨大的经济损失，导致仔猪死亡率高达 100%。为了检测、测序和遗传分析该病毒，对来自墨西哥 17 个州的 68 个一周龄仔猪样本进行了分析。实时 RT-PCR 检测结果显示，53 个样本呈阳性，证实了该病毒在 15 个州的存在。用终点 RT-PCR 对来自 10 个州的 28 个样本进行了扩增，获得了 20 个刺突基因序列。基于刺突基因的系统进化分析表明，所有墨西哥毒株均属于第 II 群，被归类为非插入缺失-S 新兴变异株。3 个毒株存在氨基酸插入：PEDv/MEX/GTO/LI-DMZC15/2015 和 PEDv/MEX/QRO/LI-DMZC45/2016 分别显示 1 个氨基酸插入（Y 和 D），PEDv/MEX/QRO/LI-DMZC49/2019 显示 1 个和 2 个氨基酸插入（C 和 SQ），第 2 个插入位于 COE 区。这些结果表明，2016-2018 年期间，非插入缺失-S 新兴变异株在墨西哥流行，其中 3 个毒株存在氨基酸插入：PEDv/MEX/GTO/IN-DMZC15/2015 和 PEDv/MEX/QRO/IN-DMZC45/2016 各有 1 个氨基酸插入（Y 和 D），PEDv/MEX/QRO/IN-DMZC49/2019 有 1 个（C）和 2 个氨基酸插入（SQ），后者位于 COE 区，可能会产生新的抗原变异株。
