The threat of climate change on tick-borne infections: rising trend of infections and geographical distribution of climate risk factors associated with ticks.

Ticks transmit a wide range of pathogens. The spread of tick-borne infections is an emerging, yet often overlooked, threat in the context of climate change. The infections have rapidly increased over the past few years in South Korea despite no significant changes in socio-economic circumstances. We investigated the impact of climate change on the surge of tick-borne infections and identified potential disease hotspots at 5  km by 5  km resolution. A composite index was constructed based on multiple climate and environmental indicators, and compared with the observed tick-borne infections. The surge of tick-borne episodes corresponded to the rising trend of the index over time. High-risk areas identified by the index can be used to prioritize locations for disease prevention activities. Monitoring climate risk factors may provide an opportunity to predict the spread of the infections in advance.