Spatial-temporal risk of Opisthorchis felineus infection in Western Siberia and the Ural Region of Russian Federation: a joint Bayesian modelling study based on survey and surveillance data.

Background: Opisthorchiasis infected by Opisthorchis felineus has represented a significant but understudied public health issue for the population residing in Western Siberia and the Ural Region of the Russian Federation. This study aimed to produce high-resolution spatial-temporal disease risk maps for guiding prevention strategy in the above region.

Methods: Data on prevalence and surveillance data reflecting reported annual incidence rate of O. felineus infection in the study region were collected through systematic review and the annual reports of the Ministry of Health of the Russian Federation. Environmental, socioeconomic and demographic data were downloaded from different open-access data sources. An advanced multivariate Bayesian geostatistical modeling approach was developed to estimate the O. felineus infection risk at high-resolution spatial-temporal by joint analysis of survey and surveillance data, incorporating potential influencing factors and spatial-temporal random effects. The annual spatial-temporal risk maps of O. felineus infection at a resolution of 5 × 5 km² were produced.

Results: The final dataset included 76 locations of survey data and 303 locations of surveillance data on O. felineus infection. The infection risk was high (> 25%) in most part of central and eastern regions, and relatively low (< 25%) in most part of western region, while temporal variations were observed across the sub-regions in recent decades. Particularly, in the densely populated eastern region, there was an increased trend of infection risk from 30.46% (95% Bayesian credible intervals, BCI 10.78-53.45%) in 1980 to 53.39% (95% BCI 13.77-91.93%) in 2019 and gradually transformed into high-risk. In the study region (excluding the western region due to data sparsity), the population-adjusted estimated prevalence was 46.61% (95% BCI 15.09-76.50%) in 2019, corresponding to approximately 7.91 million (95% BCI 2.56-12.98 million) people infected.

Conclusions: The high-resolution risk maps of O. felineus in Western Siberia and the Ural Region of the Russian Federation have effectively captured the risk profiles, suggesting the infection risk remains high in recent years and providing substantial evidence for spatial-target control and preventive strategies.