State Key Laboratory for Animal Disease Control and Prevention, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou 730046, China.
State Key Laboratory for Animal Disease Control and Prevention, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou 730046, China.
Acta Trop. 2024 Jun;254:107163. doi: 10.1016/j.actatropica.2024.107163. Epub 2024 Feb 28.
Coxiella burnetii is the causative agent of zoonotic Q fever. Animals are the natural reservoirs of C. burnetii, and domestic livestock represent the major sources of human infection. C. burnetii infection in pregnant females may causes abortion during late pregnancy, whereby massive shedding of C. burnetii with abortion products becomes aerosolized and persists in the environment. Therefore, monitoring and surveillance of this infection in livestock is important for the prevention of the C. burnetii transmission. Previous serological surveys have shown that C. burnetii infection is endemic in livestock in China. However, few data are available on the diagnosis of C. burnetii as a cause of abortion by molecular methods in livestock. To get a better understanding of the impact of C. burnetii infection on domestic livestock in China, a real-time PCR investigation was carried out on collected samples from different domestic livestock suffering abortion during 2021-2023. A total of 338 samples collected from eight herds of five livestock species were elected. The results showed that 223 (66 %) of the collected samples were positive for C. burnetii DNA using real-time PCR. For the aborted samples, 82 % (128/15) of sheep, 81 % (34/42) of goats, 44 % (15/34) of cattle, 69 % (18/26) of camels, and 50 % (17/34) of donkeys were positive for C. burnetii. Besides, 44 % (8/18) and 4 % (1/25) of asymptomatic individuals of sheep and donkey were also positive for C. burnetii. In addition, the positive samples were further confirmed by amplification and sequencing of the C. burnetii-specific isocitrate dehydrogenase (icd) gene. Phylogenetic analysis based on specific gene fragments of icd genes revealed that the obtained sequences in this study were clustered into two different groups associated with different origin of hosts and geographic regions. This is the first report confirming that C. burnetii exists in aborted samples of sheep, goats, cattle, donkeys and camels in China. Further studies are needed to fully elucidate the epidemiology of this pathogen in livestock as well as the potential risks to public health.
贝纳柯克斯体是动物源性 Q 热的病原体。动物是贝纳柯克斯体的天然宿主，而家畜是人类感染的主要来源。感染贝纳柯克斯体的孕妇可能会在妊娠晚期流产，大量的贝纳柯克斯体和流产产物脱落并气溶胶化，在环境中持续存在。因此，对家畜中这种感染的监测和监测对于预防贝纳柯克斯体的传播很重要。以前的血清学调查表明，贝纳柯克斯体感染在中国的家畜中流行。然而，很少有关于分子方法诊断家畜中贝纳柯克斯体引起流产的数据。为了更好地了解贝纳柯克斯体感染对中国家畜的影响，我们对 2021 年至 2023 年期间不同流产家畜采集的样本进行了实时 PCR 调查。从五个畜种的八个畜群中采集了 338 个样本。结果表明，使用实时 PCR 检测，338 个样本中有 223 个（66%）为贝纳柯克斯体 DNA 阳性。对于流产样本，绵羊中 82%（128/15）、山羊中 81%（34/42）、牛中 44%（15/34）、骆驼中 69%（18/26）和驴中 50%（17/34）为贝纳柯克斯体阳性。此外，绵羊和驴中无症状个体的 44%（8/18）和 4%（1/25）也为贝纳柯克斯体阳性。此外，阳性样本进一步通过扩增和测序贝纳柯克斯体特异性异柠檬酸脱氢酶（icd）基因得到确认。基于 icd 基因特异性基因片段的系统发育分析显示，本研究中获得的序列分为两组，与不同宿主来源和地理区域有关。这是首次确认在中国绵羊、山羊、牛、驴和骆驼的流产样本中存在贝纳柯克斯体。需要进一步研究以充分阐明该病原体在家畜中的流行病学以及对公共卫生的潜在风险。
