Bernard Célia, Holzmuller Philippe, Bah Madiou Thierno, Bastien Matthieu, Combes Benoit, Jori Ferran, Grosbois Vladimir, Vial Laurence
CIRAD, UMR ASTRE, Montpellier, France.
ASTRE, Univ Montpellier, CIRAD, INRAE, Montpellier, France.
Front Vet Sci. 2022 Jul 19;9:932304. doi: 10.3389/fvets.2022.932304. eCollection 2022.
Crimean-Congo hemorrhagic fever (CCHF) is a viral zoonotic disease resulting in hemorrhagic syndrome in humans. Its causative agent is naturally transmitted by ticks to non-human vertebrate hosts within an enzootic sylvatic cycle. Ticks are considered biological vectors, as well as reservoirs for CCHF virus (CCHFV), as they are able to maintain the virus for several months or even years and to transmit CCHFV to other ticks. Although animals are not symptomatic, some of them can sufficiently replicate the virus, becoming a source of infection for ticks as well as humans through direct contact with contaminated body fluids. The recent emergence of CCHF in Spain indicates that tick-human interaction rates promoting virus transmission are changing and lead to the emergence of CCHF. In other European countries such as France, the presence of one of its main tick vectors and the detection of antibodies targeting CCHFV in animals, at least in Corsica and in the absence of human cases, suggest that CCHFV could be spreading silently. In this review, we study the CCHFV epidemiological cycle as hypothesized in the French local context and select the most likely parameters that may influence virus transmission among tick vectors and non-human vertebrate hosts. For this, a total of 1,035 articles dating from 1957 to 2021 were selected for data extraction. This study made it possible to identify the tick species that seem to be the best candidate vectors of CCHFV in France, but also to highlight the importance of the abundance and composition of local host communities on vectors' infection prevalence. Regarding the presumed transmission cycle involving , as it might exist in France, at least in Corsica, it is assumed that tick vectors are still weakly infected and the probability of disease emergence in humans remains low. The likelihood of factors that may modify this equilibrium is discussed.
克里米亚-刚果出血热（CCHF）是一种病毒性人畜共患病，可导致人类出现出血热综合征。其病原体在自然疫源地的森林循环中通过蜱虫传播给非人类脊椎动物宿主。蜱虫被认为是CCHF病毒（CCHFV）的生物传播媒介和储存宿主，因为它们能够将病毒维持数月甚至数年，并将CCHFV传播给其他蜱虫。尽管动物没有症状，但其中一些动物能够充分复制病毒，通过直接接触受污染的体液成为蜱虫和人类的感染源。西班牙最近出现的CCHF表明，促进病毒传播的蜱虫与人类的相互作用率正在发生变化，并导致了CCHF的出现。在法国等其他欧洲国家，其主要蜱虫传播媒介之一的存在以及在动物体内检测到针对CCHFV的抗体，至少在科西嘉岛且无人类病例的情况下，表明CCHFV可能正在悄然传播。在本综述中，我们研究了法国当地背景下假设的CCHFV流行病学循环，并选择了最可能影响病毒在蜱虫传播媒介和非人类脊椎动物宿主之间传播的参数。为此，总共选择了1957年至2021年的1035篇文章进行数据提取。这项研究不仅能够确定在法国似乎是CCHFV最佳候选传播媒介的蜱虫种类，还能够突出当地宿主群落的丰度和组成对传播媒介感染率的重要性。关于在法国（至少在科西嘉岛）可能存在的假定传播循环，假定蜱虫传播媒介仍然感染程度较低，人类出现疾病的可能性仍然较低。文中讨论了可能改变这种平衡的因素的可能性。
