Amrani Nadia, Desario Costantina, Kadiri Ahlam, Cavalli Alessandra, Berrada Jaouad, Zro Khalil, Sebbar Ghizlane, Colaianni Maria Loredana, Parisi Antonio, Elia Gabriella, Buonavoglia Canio, Malik Jamal, Decaro Nicola
Microbiology, Immunology and Infectious Diseases Unit, Department of Veterinary Pathology and Public Health, Hassan II Agronomic and Veterinary Institute, Rabat, Morocco.
Department of Veterinary Medicine, University of Bari, Italy.
Infect Genet Evol. 2016 Jul;41:201-206. doi: 10.1016/j.meegid.2016.04.005. Epub 2016 Apr 12.
Since it first emergence in the mid-1970's, canine parvovirus 2 (CPV-2) has evolved giving rise to new antigenic variants termed CPV-2a, CPV-2b and CPV-2c, which have completely replaced the original strain and had been variously distributed worldwide. In Africa limited data are available on epidemiological prevalence of these new types. Hence, the aim of the present study was to determine circulating variants in Morocco. Through TaqMan-based real-time PCR assay, 91 samples, collected from symptomatic dogs originating from various cities between 2011 and 2015, were diagnosed. Positive specimens were characterised by means of minor groove binder (MGB) probe PCR. The results showed that all samples but one (98.9%) were CPV positive, of which 1 (1.1%) was characterised as CPV-2a, 43 (47.7%) as CPV-2b and 39 (43.3%) as CPV-2c. Interestingly, a co-infection with CPV-2b and CPV-2c was detected in 4 (4.4%) samples and 3 (3.3%) samples were not characterised. Sequencing of the full VP2 gene revealed these 3 uncharacterised strains as CPV-2c, displaying a change G4068A responsible for the replacement of aspartic acid with asparagine at residue 427, impacting the MGB probe binding. In this work we provide a better understanding of the current status of prevailing CPV strains in northern Africa.
自20世纪70年代中期首次出现以来，犬细小病毒2型（CPV-2）不断进化，产生了新的抗原变体，称为CPV-2a、CPV-2b和CPV-2c，这些变体已完全取代了原始毒株，并在全球范围内广泛分布。在非洲，关于这些新类型的流行病学患病率的可用数据有限。因此，本研究的目的是确定摩洛哥流行的变体。通过基于TaqMan的实时PCR检测，对2011年至2015年间从不同城市有症状的犬只采集的91份样本进行了诊断。通过小沟结合剂（MGB）探针PCR对阳性标本进行鉴定。结果显示，除一份样本外，所有样本（98.9%）均为CPV阳性，其中1份（1.1%）鉴定为CPV-2a，43份（47.7%）为CPV-2b，39份（43.3%）为CPV-2c。有趣的是，在4份（4.4%）样本中检测到CPV-2b和CPV-2c的共同感染，3份（3.3%）样本未鉴定。对完整VP2基因进行测序后发现，这3株未鉴定的毒株为CPV-2c，显示出G4068A的变化，导致第427位残基处的天冬氨酸被天冬酰胺取代，影响了MGB探针结合。在这项工作中，我们对北非流行的CPV毒株的现状有了更好的了解。
