1. Yueqing Center for Disease Control and Prevention (Yueqing Institute of Public Health Supervision), Yueqing, Zhejiang 325600, China; 2. Wenzhou Center for Disease Control and Prevention (Wenzhou Institute of Public Health Supervision), Wenzhou, Zhejiang 325000, China; 3. Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, Zhejiang 310050, China
Abstract：On January 22, 2024, Yueqing People's Hospital in Zhejiang Province reported a confirmed PTB case (index case) from an enterprise. Yueqing Center for Disease Control and Prevention conducted an on-site epidemiological investigation in accordance with the China Tuberculosis Prevention and Control Technical Guidelines and the Zhejiang Province Tuberculosis Cluster Infection Response Technical Plan (2022 Edition). Screening for latent tuberculosis infection (LTBI) and case confirmation were performed according to the Diagnosis for Pulmonary Tuberculosis. Two rounds of screening were carried out in March and April 2024, covering 341 individuals. A total of 122 LTBI cases were detected, with an overall detection rate of 35.78%; 23 PTB cases were identified, with an attack rate of 6.74%. The cases were predominantly male and registered residents of Liangshan Yi Autonomous Prefecture, Sichuan Province, both accounting for 65.22%. Cases were concentrated in workshops on the 2nd and 3rd floors of Zone C at the workplace, with the enterprise dormitory as the main residence. Secondary cases were diagnosed mainly between April and May 2024, and all had a clear history of exposure within the enterprise. Global spatial autocorrelation analysis showed spatial clustering of case distribution, with local hotspots identified as the inspection area on the 2nd floor and Line 1 on the 3rd floor of Zone C. There were 11 confirmed PTB cases and 12 clinically diagnosed cases. Four strains were isolated, and whole-genome sequencing analysis revealed that they belonged to Lineage 2 and Lineage 4, with pairwise single nucleotide polymorphism differences all exceeding 12. Based on the epidemiological investigation and laboratory testing, the PTB outbreak in the enterprise was determined to be a cluster outbreak resulting from multi-source importation and close contact transmission of Mycobacterium tuberculosis within the same workshop, dormitory, and household registration group, possibly associated with a concentration of migrant workers, poor ventilation in the workplace, and the lack of pre-employment PTB screening.
[1] 赵雁林,陈明亭.中国结核病防治工作技术指南[M].北京:人民卫生出版社,2021. [2] 范君,苏倩,陈健,等.重庆市一起学校肺结核聚集性疫情调查分析[J].中国防痨杂志,2022,44(8):792-796. [3] WU Q,WU K Y,ZHANG Y,et al.The role of Xpert MTB/RIF using bronchoalveolar lavage fluid in active screening:insights from a tuberculosis outbreak in a junior school in Eastern China[J/OL].Front Public Health,2023,11[2026-06-02].https://doi.org/10.3389/fpubh.2023.1292762. [4] 成君,赵雁林.学校结核病防控工作中的问题与对策[J].中国学校卫生,2021,42(12):1761-1764,1767. [5] 金芳,王林锋.慈溪市某企业一起结核病聚集性疫情流行病学调查[J].中国乡村医药,2020,27(11):66-67. [6] 李双初,郭玉霞,叶龙玲,等.湖北省孝感市某企业近年肺结核发病情况调查分析[J].中国防痨杂志,2018,40(8):898-904. [7] 中华人民共和国国家卫生和计划生育委员会.肺结核诊断:WS 288—2017[S].北京:中国标准出版社,2017. [8] 逯嘉,李婷,王丹霞,等.“十三五”期间四川省肺结核流行病学特征分析[J].疾病监测,2021,36(11):1147-1151. [9] WIENS K E,WOYCZYNSKI L P,LEDESMA J R,et al.Global variation in bacterial strains that cause tuberculosis disease:a systematic review and meta-analysis[J/OL].BMC Med,2018,16(1)[2026-06-02].https://doi.org/10.1186/s12916-018-1180-x. [10] LI Y F,YANG Y,KONG X L,et al.Transmission dynamics and phylogeography of Mycobacterium tuberculosis in China based on whole-genome phylogenetic analysis[J].Int J Infect Dis,2024,140:124-131. [11] DENG Y,HE X,et al.Molecular epidemiology of drug resistance and transmission of Mycobacterium tuberculosisin Meigu County,Sichuan Province,China[J/OL].Microbiol Spectr,2026,14(2)[2026-06-02].https://doi.org/10.1128/spectrum.02685-25. [12] XU D,LI X,et al.Epidemiological characteristics of tuberculosis among interprovincial migrants:China,2019-2023[J].China CDC Wkly,2025,7(33):1079-1086.
