title: Tuberculosis management time: an alternative parameter for measuring the tuberculosis infectious pool.
abstract: OBJECTIVE
  To demonstrate the application of TB management time as an alternative parameter to estimate the size of the tuberculosis infectious pool in West Gojjam Zone of Amhara Region, Ethiopia.
  
  
  METHODS
  In this study, we used the TB management time, i.e. the number of days from start of cough until start of treatment, to determine the infectious period. Patients with sputum smear-positive and smear-negative pulmonary TB, retreatment and an estimated number of undetected cases were included. The infectious pool was then estimated as the annual number of infectious person days in a defined population.
  
  
  RESULTS
  The TB management time of presently undiagnosed TB cases and sputum smear-positive patients contributed significantly to the infectious pool with 151,840 and 128,750 infectious person days per year, respectively. The total infectious pool including sputum smear-negative TB cases and retreatment patients in the study area was estimated at 325,410 person days or 15,447 person days per 100,000 population during the study year.
  
  
  CONCLUSIONS
  Recording TB management time may be used to estimate the infectious pool of TB and to monitor programme performance in the community.
authors.affiliation: Division of Infectious Disease Control, Norwegian Institute of Public Health, Oslo, Norway.|Institute of Health and Society, University of Oslo, Oslo, Norway.|Amhara Regional State Health Bureau, Bahir Dar, Ethiopia.|Department of Microbiology, Oslo University Hospital, Oslo, Norway.
authors.forename: Solomon A
authors.initials: SA
authors.lastname: Yimer
authors.affiliation: Division of Infectious Disease Control, Norwegian Institute of Public Health, Oslo, Norway.
authors.forename: Carol
authors.initials: C
authors.lastname: Holm-Hansen
authors.affiliation: Lovisenberg Diakonale Hospital, Oslo, Norway.
authors.forename: Dag G
authors.initials: DG
authors.lastname: Storla
authors.affiliation: Institute of Health and Society, University of Oslo, Oslo, Norway.
authors.forename: Gunnar A
authors.initials: GA
authors.lastname: Bjune
mesh_terms: D000995:Antitubercular Agents / Q000627:therapeutic use; D003371:Cough / Q000382:microbiology; D003430:Cross-Sectional Studies; D003627:Data Interpretation, Statistical; D057210:Delayed Diagnosis; D019468:Disease Management; D018563:Disease Notification / Q000592:standards; D018562:Disease Transmission, Infectious / Q000706:statistics & numerical data*; D005002:Ethiopia / Q000453:epidemiology; D006801:Humans; D015233:Models, Statistical; D009169:Mycobacterium tuberculosis / Q000302:isolation & purification; D015397:Program Evaluation / Q000379:methods; D012008:Recurrence; D012042:Registries; D019233:Retreatment; D013183:Sputum / Q000382:microbiology; D061665:Time-to-Treatment / Q000706:statistics & numerical data*; D017211:Treatment Failure; D014397:Tuberculosis, Pulmonary / Q000188:drug therapy / Q000453:epidemiology* / Q000635:transmission*
chemical_list: D000995:Antitubercular Agents
keywords: Ethiopia; TB management time; Tuberculosis; case detection rate; diagnostic delay; treatment delay