K-S Chen1, T Liu2, R-R Lin3, Y-P Peng4, G-C Xiong4. 1. Key Laboratory of Medical Molecular Virology, Fudan University, Shanghai, China; Department of Clinical Laboratory, First Affiliated Hospital of Nanchang University, Nanchang, China. 2. Department of Clinical Laboratory, First Affiliated Hospital of Nanchang University, Nanchang, China. 3. Department of Respiration, Wuning County People's Hospital, Wuning, China. 4. Department of Clinical Laboratory, Jiangxi Provincial Chest Hospital, Nanchang, China.
Abstract
SETTING: An antimony mine in Jiangxi Province, China. OBJECTIVE: To investigate the incidence of tuberculosis (TB) transmission and associated risk factors in a Chinese antimony mining community. DESIGN: Retrospective cohort study METHODS: The 15-locus mycobacterial interspersed repetitive unit-variable number of tandem repeats (MIRU-VNTR(15-China)) method was used to determine clustering of patients. A region of difference (RD105) deletion-targeted multiplex polymerase chain reaction was adopted to identify Beijing strains. Risk factors for clustering were assessed. RESULTS: Of 263 TB patients, 175 were distributed into 35 clusters. Estimated recent transmission of TB was 53.2% within the community. Patients who failed treatment were more likely to be in clusters (adjusted odds ratio [aOR] 0.03, 95%CI 2.12-6.89). Patients with multiresistant isolates were more likely to have failed treatment and to be in a cluster than those carrying a susceptible strain (aOR 0.001, 95%CI 4.89-29.7). CONCLUSIONS: Individuals who fail treatment are an important source of infection in TB transmission, and multiresistant isolates are mostly responsible for this. TB control plans need to focus on treatment failure cases in the community.
SETTING: An antimony mine in Jiangxi Province, China. OBJECTIVE: To investigate the incidence of tuberculosis (TB) transmission and associated risk factors in a Chinese antimony mining community. DESIGN: Retrospective cohort study METHODS: The 15-locus mycobacterial interspersed repetitive unit-variable number of tandem repeats (MIRU-VNTR(15-China)) method was used to determine clustering of patients. A region of difference (RD105) deletion-targeted multiplex polymerase chain reaction was adopted to identify Beijing strains. Risk factors for clustering were assessed. RESULTS: Of 263 TB patients, 175 were distributed into 35 clusters. Estimated recent transmission of TB was 53.2% within the community. Patients who failed treatment were more likely to be in clusters (adjusted odds ratio [aOR] 0.03, 95%CI 2.12-6.89). Patients with multiresistant isolates were more likely to have failed treatment and to be in a cluster than those carrying a susceptible strain (aOR 0.001, 95%CI 4.89-29.7). CONCLUSIONS: Individuals who fail treatment are an important source of infection in TB transmission, and multiresistant isolates are mostly responsible for this. TB control plans need to focus on treatment failure cases in the community.