Epidemiological characteristics and spatial clusters of pulmonary tuberculosis in Zhejiang province,2005-2011

Objective To investigate the epidemiological characteristics and spatial clusters of pulmonary tuberculosis in Zhejiang province from 2005 to 2011.Methods Based on the data from the communicable disease surveillance network system of Zhejiang Provincial Center for Disease Control and Prevention from 2005 to 2011,we employed the spatial autocorrelation method and scan statistics to identify the spatial clusters of pulmonary tuberculosis in Zhejiang province at the level of county.Results A total of 239080 pulmonary tuberculosis cases were reported from 2005 to 2011 and the average annual incidence rate was 67.50 per 100000.The male to female ratio of the cases was 2.18:1.Of all the cases,75.5% were at the ages of 15-60 years and 44.9% were farmers.Both spatial autocorrelation analysis and scan statistics revealed that most of the counties with pulmonary tuberculosis clustered in Quzhou municipality and three counties in Hangzhou municipality.On the contrary,the counties in Jiaxin,Ningbo,and Lishui municipality were regions with low pulmonary tuberculosis incidence.Conclusion The overall pulmonary tuberculosis incidence in Zhejiang province descended annually since 2006 and was lower than that of the country.Male and young adults from countries were the most susceptible groups to pulmonary tuberculosis.Quzhou was the major high-incidence region of pulmonary tuberculosis in Zhejiang province.