Environmental Predictions Department, Climate and Atmosphere Research Centre, The Cyprus Institute, Nicosia, Cyprus.
Institute for Atmospheric and Earth System Research (INAR), Faculty of Science, University of Helsinki, Helsinki, Finland.
PLoS One. 2022 Jul 20;17(7):e0269846. doi: 10.1371/journal.pone.0269846. eCollection 2022.
Tick-borne diseases are among the challenges associated with warming climate. Many studies predict, and already note, expansion of ticks' habitats to the north, bringing previously non-endemic diseases, such as borreliosis and encephalitis, to the new areas. In addition, higher temperatures accelerate phases of ticks' development in areas where ticks have established populations. Earlier works have shown that meteorological parameters, such as temperature and humidity influence ticks' survival and define their areas of habitat. Here, we study the link between climatic parameters and tick-related hospital visits as well as borreliosis incidence rates focusing on European Russia. We have used yearly incidence rates of borreliosis spanning a period of 20 years (1997-2016) and weekly tick-related hospital visits spanning two years (2018-2019). We identify regions in Russia characterized by similar dynamics of incidence rates and dominating tick species. For each cluster, we find a set of climatic parameters that are significantly correlated with the incidence rates, though a linear regression approach using exclusively climatic parameters to incidence prediction was less than 50% effective. On a weekly timescale, we find correlations of different climatic parameters with hospital visits. Finally, we trained two long short-term memory neural network models to project the tick-related hospital visits until the end of the century, under the RCP8.5 climate scenario, and present our findings in the evolution of the tick season length for different regions in Russia. Our results show that the regions with an expected increase in both tick season length and borreliosis incidence rates are located in the southern forested areas of European Russia. Oppositely, our projections suggest no prolongation of the tick season length in the northern areas with already established tick population.
蜱传疾病是与气候变暖相关的挑战之一。许多研究预测并已经注意到，蜱的栖息地向北扩张，将以前非地方性疾病（如莱姆病和脑炎）带到新的地区。此外，较高的温度会加速已经建立种群的地区蜱的发育阶段。早期的研究表明，气象参数（如温度和湿度）会影响蜱的生存并确定其栖息地的范围。在这里，我们研究了气候参数与蜱相关的医院就诊以及欧洲俄罗斯的莱姆病发病率之间的联系。我们使用了 20 年（1997-2016 年）的莱姆病年发病率和两年（2018-2019 年）的每周蜱相关医院就诊的数据。我们确定了俄罗斯具有相似发病率动态和主要蜱种的地区。对于每个聚类，我们找到了一组与发病率显著相关的气候参数，尽管仅使用气候参数进行发病率预测的线性回归方法的有效性不足 50%。在每周时间尺度上，我们发现不同气候参数与医院就诊之间存在相关性。最后，我们训练了两个长短时记忆神经网络模型，根据 RCP8.5 气候情景，预测直到本世纪末的蜱相关医院就诊情况，并在俄罗斯不同地区的蜱季长度演变中展示我们的研究结果。我们的研究结果表明，预计蜱季长度和莱姆病发病率都将增加的地区位于俄罗斯欧洲南部的森林地区。相反，我们的预测表明，在已经建立蜱种群的北部地区，蜱季长度不会延长。
