Objective To investigate the epidemiological characteristics of delayed medical care of pulmonary tuberculosis (TB) cases and associated factors in migrant and local students in Hangzhou, Zhejiang province, and provide evidence for the precision prevention and control of pulmonary TB in schools.

Methods The complete records of student pulmonary TB cases registered, treated in 14 designated tuberculosis hospitals in Hangzhou between January 2017 and December 2023 were collected. The students were classified as migrant or local ones according to whether their household registration and current residence were located in Hangzhou. The incidence of delayed medical care of pulmonary TB cases (≥14 days) was defined as the dependent variable. The incidence, temporal trends, and spatial distribution of delayed medical care were compared between the two groups. Univariate and multivariate logistic regression analyses were conducted to identify the associated factors.

Results A total of 1 608 pulmonary TB cases in students were included, including 594 cases in migrant students and 1 014 cases in local students. The overall rate of delayed medical care was 45.45% in migrant students (270/594), significantly higher than that in local students (31.46%, 319/1014) (χ²=31.606, P<0.001), and greater annual fluctuation was observed in the migrant group. Stratified by educational stage, no significant difference in the incidence of delayed medical care was observed between migrant students (29.34%, 76/259) and local students (29.20%, 165/565) at the primary and secondary school level (χ²=0.002, P=0.967). In contrast, at the university level, migrant students (57.91%, 194/335) had a significantly higher incidence of delayed medical care compared with local students (34.30%, 154/449) (χ²=43.332, P<0.001). From 2017 to 2023, the temporal trends in the incidence of delayed medical care differed between the two groups, with the incidence curves intersecting twice, in 2019 and 2021. Spatial analysis revealed stronger spatial heterogeneity of delayed medical care in migrant students, with high-incidence mainly occurring in central urban area. In contrast, local students showed relatively smaller spatial variation, but an overall increasing trend with gradual clustering toward central urban area. Multivariate logistic regression indicated that, in migrant students, case-finding method (OR=2.05, 95% CI: 1.47-2.86) and bacteriological diagnostic results (OR=0.67, 95% CI: 0.48-0.94) were independent factors associated with delayed medical care. In local students, case-finding method (OR=1.58, 95% CI: 1.21-2.07) and chest radiographic findings (OR=0.55, 95% CI: 0.42-0.73) were independent influencing factors.

Conclusion Significant differences in the incidence of delayed medical care of pulmonary TB cases were observed between migrant students and local student pulmonary TB in Hangzhou, with marked temporal, spatial, and educational-stage heterogeneity. Migrant university students were the primary contributors to this disparity. Stratified intervention strategies targetting the floating status, educational-stage characteristics, and changing social contexts of the students are needed to improve the precision and effectiveness of school-based TB prevention and control.