Development of a Technology for Spatial Risk Analysis of Tick-Borne Infections Based on Emergency Notification Data

The aim of the study was to develop and test a technology for the spatial analysis of the epidemiological risk of tick-borne infections based on geo-encoded emergency notification data.
Materials and methods. A retrospective spatial analysis of a continuous sample of emergency notifications for the Irkutsk Region over the period of 2023–2024 was conducted, including cases of tick bites (n=21,585) and tick-borne viral encephalitis (n=171). The geo-encoding of residential addresses and presumed exposure sites was performed automatically using an R-based program through the DaData application programming interface, followed by mapping using geographic information systems.
Results and discussion. The proportion of emergency notifications containing textual information suitable for geo-encoding was 48.1 % for tick bites and 52.0 % for tick-borne viral encephalitis cases. Concordance between the municipality of exposure and the patient’s district of residence was observed in only 29.6 % of tick bite cases and 30.3 % of tick-borne viral encephalitis cases. In most instances, the municipal district of the presumed tick attack site differed from the patient’s place of residence. The proposed spatial analysis approach has revealed hidden zones of tick-borne viral encephalitis infection risk in territories not included in the official list of endemic districts, and demonstrated a discrepancy between areas with high calculated incidence levels and locations with the highest concentration of infection events. The developed technology improves the accuracy of assessing the territorial risk of tick-borne infections. Implementing geoencoding features for emergency notification data into the tick-borne infection epidemiological surveillance system will ensure objective zoning for planning targeted preventive measures.

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