Department of Basic Medical Sciences, Changzhi Medical College, Changzhi, 046000, China.
State Key Laboratory for Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, 102206, China.
Sci Rep. 2022 Apr 29;12(1):6996. doi: 10.1038/s41598-022-11419-x.
In this study, we aimed to investigate the prevalence and molecular characteristics of Bartonella infections in small mammals from the central region of the Qinghai-Tibetan Plateau. Toward this, small mammals were captured using snap traps in Yushu City and Nangqian County, West China, and the spleen tissue was used for Bartonella culture. The suspected positive colonies were evaluated using polymerase chain reaction (PCR) amplification and by sequencing the citrate synthase (gltA) gene. We discovered that 31 out of the 103 small mammals tested positive for Bartonella, with an infection rate of 30.10%. Sex differences between the mammals did not result in a significant difference in infection rate (χ = 0.018, P = 0.892). However, there was a significant difference in infection rates in different small mammals (Fisher's exact probability method, P = 0.017) and habitats (χ = 7.157, P = 0.028). Additionally, 31 Bartonella strains belonging to three species were identified, including B. grahamii (25), B. japonica (4) and B. heixiaziensis (2), among which B. grahamii was the dominant epidemic strain (accounting for 80.65%). Phylogenetic analyses showed that most of the B. grahamii isolates identified in this study may be closely related to the strains isolated from Japan and China. Genetic diversity analyses revealed that B. grahamii strains had high genetic diversity, which showed a certain host and geographical specificity. The results of Tajima's test suggested that the B. grahamii followed the progressions simulated by a neutral evolutionary model in the process of evolution. Overall, a high prevalence and genetic diversity of Bartonella infection were observed in small mammals in the central region of the Qinghai-Tibetan Plateau. B. grahamii as the dominant epidemic strain may cause diseases in humans, and the corresponding prevention and control measures should be taken into consideration in this area.
在这项研究中，我们旨在调查青藏高原中部地区小型哺乳动物中巴尔通体感染的流行率和分子特征。为此，我们在中国西部玉树市和囊谦县使用捕鼠夹捕获小型哺乳动物，并使用其脾脏组织进行巴尔通体培养。使用聚合酶链反应（PCR）扩增和柠檬酸合酶（gltA）基因测序来评估疑似阳性菌落。我们发现，在 103 只测试的小型哺乳动物中，有 31 只检测到巴尔通体阳性，感染率为 30.10%。哺乳动物的性别差异并未导致感染率出现显著差异（χ=0.018，P=0.892）。然而，不同小型哺乳动物（Fisher 确切概率法，P=0.017）和栖息地（χ=7.157，P=0.028）之间的感染率存在显著差异。此外，鉴定出 31 株属于三种物种的巴尔通体菌株，包括 B. grahamii（25 株）、B. japonica（4 株）和 B. heixiaziensis（2 株），其中 B. grahamii 是主要流行株（占 80.65%）。系统发育分析表明，本研究中鉴定的大多数 B. grahamii 分离株可能与从日本和中国分离的菌株密切相关。遗传多样性分析表明，B. grahamii 菌株具有较高的遗传多样性，表现出一定的宿主和地理特异性。Tajima 检验结果表明，B. grahamii 在进化过程中遵循中性进化模型模拟的进展。总之，青藏高原中部地区小型哺乳动物中巴尔通体感染的流行率和遗传多样性较高。B. grahamii 作为主要流行株可能会引起人类疾病，应在该地区采取相应的预防和控制措施。
