Abstract: Objective Use variable-number tandem repeat (VNTR) genotyping technology to monitor the prevalence of tuberculosis in schools, and understand the genetic polymorphisms and recent transmission of tuberculosis clinical isolates in Shenzhen schools in 2018. Methods Genomic DNA was extracted from tuberculosis patients from shenzhen center for chronic disease control and designated hospitals, and 12 MIRU-VNTRs sites were detected and analyzed by Polymerase Chain Reaction (PCR).Online analysis software MIRU-VNTRS and MEGA7.6 were used for genotyping cluster analysis and phylogenetic tree mapping. Results A total of 63 tuberculosis culture-positive strains were collected in 2018, including 52 strains (82.5%) from student patients and 11 strains (17.5%) from faculty patients. The incidence of TB among students was 44.23% in high school/vocational school and 40.38% in university, while the incidence of TB among teaching staff was mainly in kindergarten (54.5%). The 63 strains of Mycobacterium tuberculosis were divided into 59 genotypes, including 56 unique genotypes and 3 gene clusters. Among them, 43 strains (68.3%) were Beijing genotype and 17 strains (27.0%) were non-Beijing genotype. In the three schools were found in two patients infected with strains of TB cases, and the results of the tuberculosis epidemiological investigation were determined to be independent infection, intra-school transmission and family cluster epidemic. Conclusion In 2018, the genotype diversity of tuberculosis strains in Shenzhen schools was high, and there were no more than 2 cases of clustered epidemics. The status of prevention and control of tuberculosis epidemics in schools is good. The MIRU-VNTRS homology identification technology can be used for routine monitoring and emergency detection of molecular epidemiological investigation of clustered tuberculosis in population.

Key words: Shenzhen city, Genotyping, Mycobacterium Tuberculosis, Recent transmission