{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,7]],"date-time":"2026-09-07T17:09:41Z","timestamp":1788800981598,"version":"build-2803163510"},"reference-count":51,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2026,9,5]],"date-time":"2026-09-05T00:00:00Z","timestamp":1788566400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pathogens"],"abstract":"<jats:p>Ticks are among the most important arthropod vectors affecting human and animal health worldwide. We present a set of globally harmonized indicators integrating hazard, exposure, and vulnerability associated with human-biting ticks and with two major tick-borne pathogens, Borrelia burgdorferi sensu lato (Lyme borreliosis), and Orthonairovirus haemorrhagiae (Crimean\u2013Congo haemorrhagic fever virus, CCHFV). Hazard indices were derived from the distributions of confirmed vector tick species. Exposure was incorporated through rural human population density, livestock density, and the abundance of competent vertebrate reservoirs and\/or amplification hosts, as applicable. Vulnerability was assessed using country-level indicators related to healthcare accessibility, socioeconomic development, and demographic dependency. The indices show spatially structured global patterns. Tick hazard is concentrated in eastern North America, Europe, Central and East Asia; Africa displays fragmented but substantial hotspots. The B. burgdorferi s.l. index is restricted to the Northern Hemisphere, following the distribution of Ixodes spp. and associated reservoir communities, with highest exposure in Europe and North America. The CCHFV index is confined to the Old World, extending from the Mediterranean region through the Middle East and Central Asia into Sub-Saharan Africa, reflecting the distribution of Hyalomma ticks and ungulates. The vulnerability indicators highlight regional patterns of high exposure and limited adaptive capacity, particularly in Sub-Saharan Africa and parts of the Middle East. Our framework provides the first global set of harmonized, high-resolution indices integrating vector ecology, reservoir communities, exposure, and vulnerability for major tick-borne diseases of humans. It offers a flexible platform for comparative epidemiology, surveillance prioritization, and public health decision-making at multiple administrative scales.<\/jats:p>","DOI":"10.3390\/pathogens15090944","type":"journal-article","created":{"date-parts":[[2026,9,7]],"date-time":"2026-09-07T16:30:02Z","timestamp":1788798602000},"page":"944","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["A Global, High-Resolution Index of Risk and Exposure of Humans to Ticks, Lyme Borreliosis, and Crimean\u2013Congo Haemorrhagic Fever"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7483-046X","authenticated-orcid":false,"given":"Agust\u00edn","family":"Estrada-Pe\u00f1a","sequence":"first","affiliation":[{"name":"Department of Animal Health, Faculty of Veterinary Medicine, University of Zaragoza, 50013 Zaragoza, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Couret, J., Schofield, S., and Narasimhan, S. (2022). The environment, the tick, and the pathogen\u2013It is an ensemble. Front. Cell. Infect. Microbiol., 12.","DOI":"10.3389\/fcimb.2022.1049646"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"373","DOI":"10.1146\/annurev-ento-052720-094533","article-title":"The impacts of climate change on ticks and tick-borne disease risk","volume":"66","author":"Gilbert","year":"2021","journal-title":"Annu. Rev. Entomol."},{"key":"ref_3","first-page":"103","article-title":"Climate change impacts on ticks and tick-borne infections","volume":"67","author":"Nuttall","year":"2022","journal-title":"Folia Microbiol."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"472","DOI":"10.1186\/s13071-025-07096-0","article-title":"Linking tick and wildlife host distributions to map risk of tick-borne diseases","volume":"18","author":"Crowder","year":"2025","journal-title":"Parasit. Vectors"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"295","DOI":"10.1016\/j.pt.2017.12.006","article-title":"The blacklegged tick, Ixodes scapularis: An increasing public health concern","volume":"34","author":"Eisen","year":"2018","journal-title":"Trends Parasitol."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"fnx244","DOI":"10.1093\/femsle\/fnx244","article-title":"Vector-borne diseases and climate change: A European perspective","volume":"365","author":"Semenza","year":"2018","journal-title":"FEMS Microbiol. Lett."},{"key":"ref_7","unstructured":"IPCC (2022). Climate Change 2022: Impacts, Adaptation and Vulnerability, Cambridge University Press."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"479","DOI":"10.1038\/s41590-020-0648-y","article-title":"Climate change: An enduring challenge for vector-borne disease prevention and control","volume":"21","author":"Dubrow","year":"2020","journal-title":"Nat. Immunol."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"20140051","DOI":"10.1098\/rstb.2014.0051","article-title":"Climate change and Ixodes tick-borne diseases of humans","volume":"370","author":"Ostfeld","year":"2015","journal-title":"Philos. Trans. R. Soc. Lond. B Biol. Sci."},{"key":"ref_10","first-page":"5","article-title":"Evidence that climate change has caused \u2018emergence\u2019 of tick-borne diseases in Europe?","volume":"293","author":"Randolph","year":"2004","journal-title":"Int. J. Med. Microbiol."},{"key":"ref_11","first-page":"2025647","article-title":"Is composition of vertebrates an indicator of the prevalence of tick-borne pathogens?","volume":"12","year":"2022","journal-title":"Infect. Ecol. Epidemiol."},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Crimmins, A., Balbus, J., Gamble, J.L., Beard, C.B., Bell, J.E., Dodgen, D., Eisen, R.J., Fann, N., Hawkins, M.D., and Herring, S.C. (2016). Chapter 5: Vector-borne diseases, The Impacts of Climate Change on Human Health in the United States: A Scientific Assessment.","DOI":"10.7930\/J02F7KCR"},{"key":"ref_13","first-page":"1","article-title":"Effects of climate and climate change on vectors and vector-borne diseases","volume":"1","author":"Ogden","year":"2016","journal-title":"Trop. Med. Infect. Dis."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"501","DOI":"10.1016\/j.amepre.2008.08.018","article-title":"Community-based adaptation to the health impacts of climate change","volume":"35","author":"Ebi","year":"2008","journal-title":"Am. J. Prev. Med."},{"key":"ref_15","unstructured":"World Health Organization (WHO) (2021). Guidance on Vulnerability and Adaptation to Climate Change Impacts on Health, WHO Press."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"11","DOI":"10.1186\/s13071-018-3240-7","article-title":"Combination of microbiome analysis and serodiagnostics to assess the risk of pathogen transmission by ticks to humans and animals in central Germany","volume":"12","author":"Regier","year":"2019","journal-title":"Parasit. Vectors"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"349","DOI":"10.1093\/jme\/tjv237","article-title":"County-scale distribution of Ixodes scapularis and Ixodes pacificus (Acari: Ixodidae) in the continental United States","volume":"53","author":"Eisen","year":"2016","journal-title":"J. Med. Entomol."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"136","DOI":"10.1128\/CMR.17.1.136-173.2004","article-title":"Global change and human vulnerability to vector-borne diseases","volume":"17","author":"Sutherst","year":"2004","journal-title":"Clin. Microbiol. Rev."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"166","DOI":"10.1186\/s40249-017-0375-2","article-title":"Addressing vulnerability, building resilience: Community-based adaptation to vector-borne diseases in the context of global change","volume":"6","author":"Bardosh","year":"2017","journal-title":"Infect. Dis. Poverty"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"3","DOI":"10.1177\/1757975912470062","article-title":"Beyond \u2018vulnerable groups\u2019: Contexts and dynamics of vulnerability","volume":"20","author":"Zarowsky","year":"2013","journal-title":"Glob. Health Promot."},{"key":"ref_21","doi-asserted-by":"crossref","unstructured":"Guglielmone, A.A., and Robbins, R.G. (2018). Hard Ticks (Acari: Ixodida: Ixodidae) Parasitizing Humans, Springer.","DOI":"10.1007\/978-3-319-95552-0"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"2405074","DOI":"10.1080\/07853890.2024.2405074","article-title":"Machine learning algorithms for the evaluation of risk by tick-borne pathogens in Europe","volume":"56","year":"2024","journal-title":"Ann. Med."},{"key":"ref_23","doi-asserted-by":"crossref","unstructured":"Scharlemann, J.P., Benz, D., Hay, S.I., Purse, B.V., Tatem, A.J., Wint, G.W., and Rogers, D.J. (2008). Global data for ecology and epidemiology: A novel algorithm for temporal Fourier processing MODIS data. PLoS ONE, 3.","DOI":"10.1371\/journal.pone.0001408"},{"key":"ref_24","unstructured":"Hijmans, R., Brown, A., and Barbosa, M. (terra: Spatial Data Analysis, 2026). terra: Spatial Data Analysis, R Package Version 1.9-11."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"102","DOI":"10.1038\/s41597-026-07130-5","article-title":"Geographical dataset of questing nymphal density for three key tick vector species of Lyme disease","volume":"13","author":"Zhang","year":"2026","journal-title":"Sci. Data"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"327","DOI":"10.1111\/j.2041-210X.2011.00172.x","article-title":"Selecting pseudo-absences for species distribution models: How, where and how many?","volume":"3","author":"Jiguet","year":"2012","journal-title":"Methods Ecol. Evol."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"102485","DOI":"10.1016\/j.ttbdis.2025.102485","article-title":"Tick hazard in a central European country: Mapping Europe\u2019s principal tick-borne disease vector across Germany","volume":"16","author":"Springer","year":"2025","journal-title":"Ticks Tick Borne Dis."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"93","DOI":"10.1016\/j.antiviral.2017.05.010","article-title":"The role of ticks in the maintenance and transmission of Crimean-Congo hemorrhagic fever virus: A review of published field and laboratory studies","volume":"144","author":"Gargili","year":"2017","journal-title":"Antivir. Res."},{"key":"ref_29","doi-asserted-by":"crossref","unstructured":"Estrada-Pe\u00f1a, A., Carnell, O., Wijburg, S.R., Holding, M., and Sprong, H. (2026). Crimean\u2013congo haemorrhagic fever virus circulates within broad ecological networks of ticks and vertebrates. PLoS Negl. Trop. Dis., 20.","DOI":"10.1371\/journal.pntd.0013783"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"043001","DOI":"10.1088\/1748-9326\/11\/4\/043001","article-title":"Few vertebrate species dominate the Borrelia burgdorferi s.l. life cycle","volume":"11","author":"Hofmeester","year":"2016","journal-title":"Environ. Res. Lett."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"2292","DOI":"10.1038\/s41598-025-85873-8","article-title":"Spatial analysis and risk mapping of Crimean-Congo hemorrhagic fever (CCHF) in Sub-Saharan Africa","volume":"15","author":"Ilboudo","year":"2025","journal-title":"Sci. Rep."},{"key":"ref_32","unstructured":"Si-moussi, S., and Thuiller, W. (2024). Species Habitat Suitability of European Terrestrial Vertebrates for Contemporary Climate and Land Use (Version 1), German Centre for Integrative Biodiversity Research."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"109400","DOI":"10.1016\/j.isci.2024.109297","article-title":"Global One Health index for zoonoses: A performance assessment in 160 countries and territories","volume":"27","author":"Sun","year":"2024","journal-title":"iScience"},{"key":"ref_34","unstructured":"Marin-Ferrer, M., Vernaccini, L., and Poljansek, K. (2017). Index for Risk Management. INFORM Concept and Methodology Report\u2014Version 2017, Publications Office of the European Union. EUR 28655 EN."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"1835","DOI":"10.1038\/s41591-020-1059-1","article-title":"Global maps of travel time to healthcare facilities","volume":"26","author":"Weiss","year":"2020","journal-title":"Nat. Med."},{"key":"ref_36","first-page":"782","article-title":"The index of \u201ceconomic independence\u201d: A new measure of an economy\u2019s ability to survive unilaterally","volume":"51","author":"Helmy","year":"2017","journal-title":"J. Econ. Issues"},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"139","DOI":"10.1089\/vbz.2022.0068","article-title":"The epidemiology of Lyme borreliosis in Europe: An updated review on a growing public health issue","volume":"23","author":"Stark","year":"2023","journal-title":"Vector-Borne Zoonotic Dis."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"499","DOI":"10.3201\/eid2702.202728","article-title":"Use of commercial claims data for evaluating trends in Lyme disease diagnoses, United States, 2010\u20132018","volume":"27","author":"Schwartz","year":"2021","journal-title":"Emerg. Infect. Dis."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"172","DOI":"10.1089\/vbz.2022.0070","article-title":"Incidence of Lyme borreliosis in Europe: A systematic review (2005\u20132020)","volume":"23","author":"Burn","year":"2023","journal-title":"Vector-Borne Zoonotic Dis."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"101331","DOI":"10.1016\/j.onehlt.2026.101331","article-title":"Predicting the spatio-temporal risk of human tick-borne encephalitis (TBE) in Europe by combining hazard and exposure drivers","volume":"21","author":"Dagostin","year":"2026","journal-title":"One Health"},{"key":"ref_41","doi-asserted-by":"crossref","unstructured":"Estrada-Pe\u00f1a, A., Gray, J.S., Kahl, O., Lane, R.S., and Nijhof, A.M. (2013). Research on the ecology of ticks and tick-borne pathogens\u2014Methodological principles and caveats. Front. Cell. Infect. Microbiol., 3.","DOI":"10.3389\/fcimb.2013.00029"},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"190","DOI":"10.1080\/20477724.2026.2614633","article-title":"Global risk assessment of Lyme borreliosis transmission","volume":"120","author":"Olivero","year":"2026","journal-title":"Pathog. Glob. Health"},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"104735","DOI":"10.1016\/j.ijpara.2025.09.005","article-title":"Climate driven patterns shape clusters of co-occurring ticks and vertebrates in the Western Palearctic-Tropics","volume":"56","author":"Wijburg","year":"2026","journal-title":"Int. J. Parasitol."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"102083","DOI":"10.1016\/j.ttbdis.2022.102083","article-title":"Integrated human behavior and tick risk maps to prioritize Lyme disease interventions using a One Health approach","volume":"14","author":"Bouchard","year":"2023","journal-title":"Ticks Tick Borne Dis."},{"key":"ref_45","doi-asserted-by":"crossref","unstructured":"Estrada-Pe\u00f1a, A., Cevidanes, A., Sprong, H., and Mill\u00e1n, J. (2021). Pitfalls in tick and tick-borne pathogens research, some recommendations and a call for data sharing. Pathogens, 10.","DOI":"10.3390\/pathogens10060712"},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"13","DOI":"10.7763\/IJCTE.2025.V17.1364","article-title":"Machine learning-based techniques for assessing critical factors for European tick abundance","volume":"17","author":"Lansdell","year":"2025","journal-title":"Int. J. Comput. Theory Eng."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"139","DOI":"10.1093\/jmedent\/45.1.139","article-title":"Estimating reservoir competence of Borrelia burgdorferi hosts: Prevalence and infectivity, sensitivity, and specificity","volume":"45","author":"Brunner","year":"2008","journal-title":"J. Med. Entomol."},{"key":"ref_48","doi-asserted-by":"crossref","unstructured":"van Wieren, S.E., and Hofmeester, T.R. (2016). The role of large herbivores in Ixodes ricinus and Borrelia burgdorferi s.l. dynamics. Ecology and Prevention of Lyme Borreliosis, Wageningen Academic Publishers.","DOI":"10.3920\/978-90-8686-838-4_6"},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"1075","DOI":"10.1038\/s41467-021-21375-1","article-title":"Mapping ticks and tick-borne pathogens in China","volume":"12","author":"Zhao","year":"2021","journal-title":"Nat. Commun."},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"102621","DOI":"10.1016\/j.ttbdis.2026.102621","article-title":"Ticks in the landscape: Fragmentation impacts density of Europe\u2019s principal tick-borne disease vector, Ixodes ricinus, across Germany","volume":"17","author":"Springer","year":"2026","journal-title":"Ticks Tick Borne Dis."},{"key":"ref_51","doi-asserted-by":"crossref","unstructured":"Spengler, J.R., and Estrada-Pe\u00f1a, A. (2018). Host preferences support the prominent role of Hyalomma ticks in the ecology of Crimean-Congo hemorrhagic fever. PLoS Negl. Trop. Dis., 12.","DOI":"10.1371\/journal.pntd.0006248"}],"container-title":["Pathogens"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2076-0817\/15\/9\/944\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,9,7]],"date-time":"2026-09-07T16:46:41Z","timestamp":1788799601000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2076-0817\/15\/9\/944"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,9,5]]},"references-count":51,"journal-issue":{"issue":"9","published-online":{"date-parts":[[2026,9]]}},"alternative-id":["pathogens15090944"],"URL":"https:\/\/doi.org\/10.3390\/pathogens15090944","relation":{},"ISSN":["2076-0817"],"issn-type":[{"value":"2076-0817","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,9,5]]}}}