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[Display omitted] • Impacts of climate and land use change on the distribution of ticks were explored. • A model of different ticks showed diverse sensitivities to environmental factors. • The future distribution probability decreased under the scenario SSP5-RCP8.5. • The future potential distribution of ticks shifted further north in China. Ticks are known as vectors of several pathogens causing various human and animal diseases including Lyme borreliosis, tick-borne encephalitis, and Crimean-Congo hemorrhagic fever. While China is known to have more than 100 tick species well distributed over the country, our knowledge on the likely distribution of ticks in the future remains very limited, which hinders the prevention and control of the risk of tick-borne diseases. In this study, we selected four representative tick species which have different regional distribution foci in mainland China. i.e., Dermacentor marginatus , Dermacentor silvarum , Haemaphysalis longicornis and Ixodes granulatus. We used the MaxEnt model to identify the key environmental factors of tick occurrence and map their potential distributions in 2050 under four combined climate and socioeconomic scenarios (i.e., SSP1-RCP2.6, SSP2-RCP4.5, SSP3-RCP7.0 and SSP5-RCP8.5). We found that the extent of the urban fabric, cropland and forest, temperature annual range and precipitation of the driest month were the main determinants of the potential distributions of the four tick species. Under the combined scenarios, with climate warming, the potential distributions of ticks shifted to further north in China. Due to a decrease in the extent of forest, the distribution probability of ticks declined in central and southern China. In contrast with previous findings on an estimated amplification of tick distribution probability under the extreme emission scenario (RCP8.5), our studies projected an overall reduction in the distribution probability under RCP8.5, owing to an expected effect of land use. Our results could provide new data to help identify the emerging risk areas, with amplifying suitability for tick occurrence, for the prevention and control of tick-borne zoonoses in mainland China. Future directions are suggested towards improved quantity and quality of the tick occurrence database, comprehensiveness of factors and integration of different modelling approaches, and capability to model pathogen spillover at the human-tick interface. [ABSTRACT FROM AUTHOR]

Ornithodoros ticks as vectors of pathogens have had serious implications on public health. In China, these ticks are mainly distributed among arid and semiarid areas of the northwest. To improve prevention and risk control of such tick-borne diseases, suitable habitats for four Ornithodoros tick species found in China were predicted using a Maxent model. These habitats were identified based on the global geographic distributions that the tick is known to inhabit. For this study, literature reviews were conducted for each Ornithodoros species at a global level based on published studies and available online databases. Study results showed that high species suitability was primarily concentrated in northwest China for the species Ornithodoros lahorensis , O. papillipes , and O. tartakovskyi , with O. capensis limited to a predicted distribution along the coast in southeastern China. Under future climate conditions Representative Concentration Pathway scenario 4.5 and 8.5, suitable habitats for O. lahorensis , O. papillipes , and O. tartakovskyi were predicted to shift and would likely increase the potential of the species to spread, and O. capensis would reduce compared with the current climatic conditions. For all four species, temperature and precipitation were the main variables influencing distribution. • Northwest China was high species suitability areas for Ornithodoros. • O. capensis limited to a predicted distribution along the coast in southeastern China. • Using atmospheric and ground-derived data to assess the environmental niche. [ABSTRACT FROM AUTHOR]