University of Abomey-Calavi (UAC), Communicable Diseases Research Unit (URMAT), 01 PO Box: 2009, Cotonou, Benin.
Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Institute of Bacterial Infections and Zoonoses, National Reference Laboratory for Q Fever, Jena, Germany.
Ticks Tick Borne Dis. 2022 May;13(3):101926. doi: 10.1016/j.ttbdis.2022.101926. Epub 2022 Feb 16.
Q fever is a global zoonotic infection caused by the intracellular Gram-negative bacterium Coxiella burnetii. Historically, it is considered a vector-borne disease, but the role of ticks in transmission has not fully been elucidated yet. Excretion of C. burnetii in tick feces and saliva is well documented but the role of these findings or the epidemiological context is discussed controversially. Thus, the aim of this study was to determine the prevalence of C. burnetii DNA in ticks to clarify the potential role of tick species for maintenance of C. burnetii infection. A literature review was performed using Google scholar, Agora, Science Direct, PubMed and Scopus to identify original studies on C. burnetii DNA presence in ticks. The search was limited to literature published from 2009 to 2020 in English and French and focused on data obtained by molecular detection of C. burnetii DNA in ticks. Overall, the prevalence of C. burnetii in ticks collected in Africa varied from 2.91% to 13.97%, in Europe from 2.46% to 10.52% and the Middle East from 4.76% to 12.53%. Ticks collected from animals showed a prevalence of 8% (95% CI: 6%-10%), followed by ticks collected from the environment and animals of 7% (95% CI: 5%-10%). C. burnetii DNA has been found in samples of many tick species with the highest prevalence in Rhipicephalus evertsi and Amblyomma variegatum. However, most of these studies did not include a differentiation between C. burnetii and Coxiella-like endosymbionts making it finally difficult to estimate the potential role that ticks play in the epidemiology of Q fever. Therefore, it is necessary to analyze the vector competence of different tick species to transmit C. burnetii. Knowledge of the vector and reservoir competence of ticks is important for taking adequate preventive measures to limit infection risks.
Q 热是一种由细胞内革兰氏阴性细菌贝氏柯克斯体引起的全球性人畜共患感染。从历史上看，它被认为是一种媒介传播的疾病，但蜱在传播中的作用尚未完全阐明。蜱粪便和唾液中贝氏柯克斯体的排泄得到了充分的证明，但这些发现或流行病学背景的作用仍存在争议。因此，本研究旨在确定蜱中贝氏柯克斯体 DNA 的流行率，以明确蜱种在维持贝氏柯克斯体感染中的潜在作用。使用 Google Scholar、Agora、Science Direct、PubMed 和 Scopus 进行文献回顾，以确定关于蜱中贝氏柯克斯体 DNA 存在的原始研究。搜索仅限于 2009 年至 2020 年期间以英语和法语发表的文献，并侧重于通过分子检测从蜱中获得的贝氏柯克斯体 DNA 数据。总体而言，在非洲收集的蜱中，贝氏柯克斯体的流行率从 2.91%到 13.97%不等，在欧洲从 2.46%到 10.52%不等，在中东从 4.76%到 12.53%不等。从动物身上采集的蜱的流行率为 8%（95%CI：6%-10%），其次是从环境和动物身上采集的蜱，流行率为 7%（95%CI：5%-10%）。已在许多蜱种的样本中发现贝氏柯克斯体 DNA，其中在璃眼蜱和三棘血蜱中发现的流行率最高。然而，这些研究大多数都没有区分贝氏柯克斯体和柯克斯样内共生体，因此最终难以估计蜱在 Q 热流行病学中的潜在作用。因此，有必要分析不同蜱种传播贝氏柯克斯体的媒介能力。了解蜱的媒介和储存能力对于采取适当的预防措施来限制感染风险非常重要。
