Department of Immunopathology of Infectious and Parasitic Diseases, Medical University of Warsaw, 3C Pawińskiego Street, 02-106, Warsaw, Poland.
Department of Parasitology, Faculty of Biology, University of Warsaw, 1 Miecznikowa Street, 02-096, Warsaw, Poland.
Parasit Vectors. 2021 Jul 1;14(1):348. doi: 10.1186/s13071-021-04849-5.
Lyme borreliosis (LB) is the most common vector-borne disease in Europe. Monitoring changes in the prevalence of different Borrelia species in ticks may be an important indicator of risk assessment and of differences in pathogenicity in humans. The objective of our study was to assess the prevalence, co-infection and distribution of Borrelia and Babesia species in ticks removed from humans in a large sample collected during a study period of 4 years.
The ticks were collected throughout Poland from March to November over 4-year period from 2016 to 2019. All ticks (n = 1953) were morphologically identified in terms of species and developmental stage. Molecular screening for Borrelia and Babesia by amplification of the flagellin gene (flaB) or 18S rRNA marker was performed. Pathogen identity was confirmed by Sanger sequencing or PCR-restriction fragment length polymorphism analysis.
The ticks removed from humans in Poland during this study belonged to two species: Ixodes ricinus (97%) and Dermacentor reticulatus (3%). High Borrelia prevalence (25.3%), including B. miyamotoi (8.4%), was confirmed in Ixodes ricinus ticks removed from humans, as was the change in frequency of occurrence of Borrelia species during the 4-year study. Despite Babesia prevalence being relatively low (1.3%), the majority of tested isolates are considered to be pathogenic to humans. Babesia infection was observed more frequently among Borrelia-positive ticks (2.7%) than among ticks uninfected with Borrelia (0.8%). The most frequent dual co-infections were between Borrelia afzelii and Babesia microti. The presence of Borrelia was also confirmed in D. reticulatus (12.7%); however the role of these ticks in spirochete transmission to susceptible hosts is still unclear.
Although the overall risk of developing LB after a tick bite is low in Europe, knowledge of the prevalence and distribution of Borrelia and Babesia species in ticks might be an important indicator of the risk of both these tick-borne diseases.
莱姆病（LB）是欧洲最常见的虫媒传染病。监测蜱虫中不同伯氏疏螺旋体的流行情况变化可能是评估风险和人类致病性差异的重要指标。我们的研究目的是评估在从 2016 年至 2019 年为期 4 年的研究期间收集的大样本中，从人类身上采集的蜱虫中伯氏疏螺旋体和巴贝虫的流行率、合并感染和分布情况。
在 2016 年至 2019 年的 4 年期间，从波兰各地的 3 月至 11 月期间收集了所有蜱虫（n=1953），并根据物种和发育阶段进行形态学鉴定。通过扩增鞭毛蛋白基因（flaB）或 18S rRNA 标记物对伯氏疏螺旋体和巴贝虫进行分子筛选。通过 Sanger 测序或 PCR-限制性片段长度多态性分析确认病原体身份。
从波兰研究期间人类身上采集的蜱虫属于两个物种：蓖子硬蜱（97%）和血红扇头蜱（3%）。在从人类身上采集的蓖子硬蜱中，证实了高流行率的伯氏疏螺旋体（25.3%），包括伯氏疏螺旋体 miyamotoi（8.4%），并确认了在 4 年研究期间伯氏疏螺旋体物种的发生频率变化。尽管巴贝虫的流行率相对较低（1.3%），但大多数检测到的分离株被认为对人类具有致病性。在感染伯氏疏螺旋体的蜱虫（2.7%）中比未感染伯氏疏螺旋体的蜱虫（0.8%）中更频繁地观察到巴贝虫感染。最常见的双重合并感染是伯氏疏螺旋体 afzelii 和巴贝虫 microti。在血红扇头蜱中也证实存在伯氏疏螺旋体（12.7%）；然而，这些蜱虫在螺旋体传播给易感宿主中的作用仍不清楚。
尽管在欧洲，被蜱叮咬后患莱姆病的总体风险较低，但了解蜱虫中伯氏疏螺旋体和巴贝虫的流行率和分布情况可能是这两种蜱传疾病风险的重要指标。
