T Vindenes1, M R Jordan2, A Tibbs3, T J Stopka4, D Johnson4, J Cochran3. 1. Division of Geographic Medicine and Infectious Diseases, Tufts Medical Center, 800 Washington Street, Tufts University, Boston, MA, USA. Electronic address: tvindenes@tuftsmedicalcenter.org. 2. Division of Geographic Medicine and Infectious Diseases, Tufts Medical Center, 800 Washington Street, Tufts University, Boston, MA, USA; Department of Public Health and Community Health, Tufts University School of Medicine, 136 Harrison Avenue, Boston, MA, USA. 3. Massachusetts Department of Public Health, 305 South Street, Boston, MA, USA. 4. Department of Public Health and Community Health, Tufts University School of Medicine, 136 Harrison Avenue, Boston, MA, USA.
Abstract
BACKGROUND: Massachusetts had a rate of 2.8 cases of tuberculosis (TB) per 100,000 individuals in 2015. Although TB in Massachusetts is on the decline, the case rate remains far above the 2020 National TB Target of 1.4 per 100,000. To reduce the TB case rate in Massachusetts, it is necessary to understand the local epidemiology and transmission risks. METHODS: We used an existing TB case database of Massachusetts TB cases in the time frame from 2012 to 2015, which links de-identified patient demographic information with TB genotypes obtained from the United States Centers for Disease Control and Prevention's (CDC) TB Genotyping Information Management System database. Two or more cases with identical genotypes, which were close in space (within 50 km), as determined in a geographic information system (GIS), and time (3 years), were considered TB clusters. RESULTS: We analyzed 543 genotyped cases. We identified a total of 85 cases that met the TB cluster criteria, and a total of 33 clusters. US-born individuals (p = 0.003), homeless individuals (p = 0.001) and those reporting illicit substance use (p = 0.001) and alcohol use (p = 0.001) were more likely to appear in a TB cluster. CONCLUSION: Through a combined genotypic and spatial epidemiological approach, we identified populations and individuals more likely to be in a TB cluster. Testing populations identified as at risk for being in a TB cluster, and providing appropriate treatment, may decrease the overall TB case rate and support efforts to achieve national 2020 TB targets.
BACKGROUND: Massachusetts had a rate of 2.8 cases of tuberculosis (TB) per 100,000 individuals in 2015. Although TB in Massachusetts is on the decline, the case rate remains far above the 2020 National TB Target of 1.4 per 100,000. To reduce the TB case rate in Massachusetts, it is necessary to understand the local epidemiology and transmission risks. METHODS: We used an existing TB case database of Massachusetts TB cases in the time frame from 2012 to 2015, which links de-identified patient demographic information with TB genotypes obtained from the United States Centers for Disease Control and Prevention's (CDC) TB Genotyping Information Management System database. Two or more cases with identical genotypes, which were close in space (within 50 km), as determined in a geographic information system (GIS), and time (3 years), were considered TB clusters. RESULTS: We analyzed 543 genotyped cases. We identified a total of 85 cases that met the TB cluster criteria, and a total of 33 clusters. US-born individuals (p = 0.003), homeless individuals (p = 0.001) and those reporting illicit substance use (p = 0.001) and alcohol use (p = 0.001) were more likely to appear in a TB cluster. CONCLUSION: Through a combined genotypic and spatial epidemiological approach, we identified populations and individuals more likely to be in a TB cluster. Testing populations identified as at risk for being in a TB cluster, and providing appropriate treatment, may decrease the overall TB case rate and support efforts to achieve national 2020 TB targets.
Authors: Adam Readhead; Alicia H Chang; Jo Kay Ghosh; Frank Sorvillo; Julie Higashi; Roger Detels Journal: BMC Public Health Date: 2020-09-21 Impact factor: 3.295