A molecular and spatial clustering analysis of active pulmonary tuberculosis patients in Funing county of Jiangsu Province, China / 中华传染病杂志

ABSTRACT

Objective To describe the distribution and spatial clustering of active pulmonary tuberculosis patients in Funing county of Jiangsu Province,China,and to determine the rules of recent transmission in TB patients and help establish the strategy of TB control with the results of genetic typing of Mycobacterium tuberculosis (M.TB).Methods Newly reported and retreated tuberculosis patients registered in Funing county,Jiangsu Province between Jun 1,2009 and Nov 30,2010 were recruited as research subjects.Geographic information system was applied to analysis the spatial clustering of tuberculosis patients.The M.TB isolates were genotyped by mycobacterial interspersed repetitive units (MIRU).Cluster was defined as two or more patients' M.TB isolates harboring identical MIRU genotype.Results During the study period,there were a total of 681 active pulmonary tuberculosis patients reported.Global Moran's I value and local Moran's I value indicated a random and sporadical manner instead of global spatial clustering of tuberculosis patients in Funing county.Spatial scan statistics (SaTScan) showed that the patients in Guoshu town was statistically significant in spatial clustering (RR=1.85,P=0.036).Among 169 strains of M.TB,27 strains distributed in 12 clusters,which indicated recent transmission among patients within the cluster.Conclusions In rural areas with high tuberculosis incidence,it is less likely to have massive tuberculosis outbreak.Sporadic transmission of tuberculosis may have played an important role in the transmission of tuberculosis in high prevalence area.