Evaluating 10-year Changes in Relative Risk of Smear Positive Tuberculosis in Iran Using Spatial Modelling: 2010-2019

Background and Objectives According to the importance of preventing tuberculosis, it is necessary to identify areas with a high relative risk. Subjects and Methods This is an ecological study. To estimate the relative risk of SPTB (smear-positive tuberculosis), the number of SPTB cases and at-risk population for each province was extracted from the data set of the Tuberculosis and Leprosy Department of the Ministry of Health. Relative risk (RR) estimation was obtained using Log-Normal and BYM models. Deviance information criterion was used to compare the performance of the models. Analyses were done in WinBUGS1.4.3 and ArcGIS10.8 software. Results The highest relative risk was seen in 2010 for Sistan and Baluchestan Province as RR = 4.02 with (95%CI: 3.73-4.32) and the lowest for Chaharmahal and Bakhtiari Province with RR= 0.22 [95%CI: 0.13-0.35). The highest relative risk in Sistan and Baluchestan Province in 2020 was RR= 3.77 (95%CI: 3.45-4.01), and the lowest relative risk was in Kohgiluyeh and Boyer Ahmad Province with RR= 0.21 (95% CI: 0.10-0.36). Conclusion The risk of tuberculosis was generally high in provinces bordering countries with high rates of tuberculosis and provinces with humid climates. The movement of populations from high-risk provinces and high-burden countries can be one of the main challenges in controlling tuberculosis. However, the pattern of risk reduction in provinces bordering high-risk countries shows relatively good progress in TB control programs and reminds us of the need for detailed studies on the pattern of increase in other provinces