title: Increased incidence of the outbreak strain of Mycobacterium tuberculosis in the surrounding community after an outbreak in a jail.
abstract: BACKGROUND
  Between 1995 and 1997, a tuberculosis outbreak occurred in a large, urban jail. We investigated whether the outbreak strain of Mycobacterium tuberculosis (M. tuberculosis) was circulating in the surrounding community after that outbreak.
  
  
  METHODS
  We performed a retrospective cohort study of people with tuberculosis in Shelby County, TN, from January 1998 through August 1999, with molecular fingerprinting of M. tuberculosis strains.
  
  
  RESULTS
  From January 1998 through August 1999, 23% of cases in the community involved a strain of M. tuberculosis that was indistinguishable from the previous jail outbreak strain. Twelve people (63%) with that strain had no history of recent incarceration.
  
  
  CONCLUSIONS
  Two years after a tuberculosis outbreak in the jail, the outbreak strain was more prevalent in the surrounding community than it was during the jail outbreak. Jails can be important reservoirs of tuberculosis, which may subsequently circulate outside the institution. If efforts to eliminate tuberculosis are to be successful, the disease must be controlled successfully in such high-risk populations.
authors.affiliation: Communicable and Environmental Disease Services, Tennessee Department of Health and Department of Preventive Medicine, Vanderbilt University School of Medicine, Nashville, TN 37247, USA. tjones4@mail.state.tn.us
authors.forename: Timothy F
authors.initials: TF
authors.lastname: Jones
authors.forename: Charles L
authors.initials: CL
authors.lastname: Woodley
authors.forename: Francis F
authors.initials: FF
authors.lastname: Fountain
authors.forename: William
authors.initials: W
authors.lastname: Schaffner
mesh_terms: D015331:Cohort Studies; D017714:Community-Acquired Infections / Q000453:epidemiology* / Q000235:genetics / Q000635:transmission; D016172:DNA Fingerprinting; D004196:Disease Outbreaks; D006801:Humans; D015994:Incidence; D009169:Mycobacterium tuberculosis / Q000235:genetics / Q000302:isolation & purification*; D011330:Prisons; D012189:Retrospective Studies; D012307:Risk Factors; D013997:Time Factors; D014376:Tuberculosis / Q000453:epidemiology* / Q000235:genetics / Q000635:transmission