Outbreak of tuberculosis in a homeless population involving multiple sites of transmission
Abstract:SETTING: During 2002–2003, a large outbreak of tuberculosis (TB) occurred among persons using multiple homeless facilities in King County, Washington.
OBJECTIVE: To control the transmission of TB in multiple settings.
DESIGN: In 2002, contacts exposed to patients in homeless facilities were screened using tuberculin skin tests (TSTs) and symptom review. Based on these screening results, sites of transmission were identified and prioritised, and exposed cohorts at these sites were offered intensive screening tests in 2003 (e.g., symptom review, TST, chest radiograph [CXR], sputum examination and culture). Mycobacterium tuberculosis isolates from patients were genotyped using PCR-based methods to identify outbreak-associated patients quickly.
RESULTS: During 2002–2003, 48 (15%) of 313 patients diagnosed in King County were outbreak-associated; 47 culture-positive patients had isolates that matched the outbreak strain by genotyping. Three facilities visited by >12 patients in 2002 had a higher prevalence of TST positive results (approximately 30%) among clients compared with the background rate (7%) in the homeless community. Screening contacts with one sputum culture was as sensitive as CXR in detecting TB disease (77% vs. 62%, respectively).
CONCLUSIONS: A comprehensive, resource-intensive approach likely helped to control transmission. This outbreak highlights the vulnerability of homeless populations and the need to maintain robust TB programs in urban settings.
Document Type: Regular Paper
Affiliations: 1: Epidemiology Program Office, Centers for Disease Control and Prevention, Atlanta, Georgia, USA 2: Division of Tuberculosis Elimination, National Center for HIV, STD and TB Prevention, Centers for Disease Control and Prevention, Atlanta, Georgia, USA 3: Public Health—Seattle & King County Tuberculosis Control Program, Seattle, Washington, USA 4: Seattle Biomedical Research Institute, Seattle, Washington, USA 5: University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA; and Central Arkansas Veterans Healthcare System, Little Rock, Arkansas, USA 6: Public Health—Seattle & King County Tuberculosis Control Program, Seattle, Washington, USA; and Division of Pulmonary and Critical Care Medicine, University of Washington, Seattle, Washington, USA
Publication date: 2006-06-01
The International Journal of Tuberculosis and Lung Disease publishes articles on all aspects of lung health, including public health-related issues such as training programmes, cost-benefit analysis, legislation, epidemiology, intervention studies and health systems research. The IJTLD is dedicated to the continuing education of physicians and health personnel and the dissemination of information on tuberculosis and lung health world-wide.
Certain IJTLD articles are selected for translation into French, Spanish, Chinese or Russian. They are available on the Union website
- Editorial Board
- Information for Authors
- Subscribe to this Title
- International Journal of Tuberculosis and Lung Disease
- Public Health Action
- Ingenta Connect is not responsible for the content or availability of external websites