title: Control of (multi)drug resistance and tuberculosis incidence over 23 years in the context of a well-supported tuberculosis programme in rural Malawi.
abstract: BACKGROUND
  The rise in tuberculosis (TB) incidence following generalized HIV epidemics can overwhelm TB control programmes in resource-limited settings, sometimes accompanied by rising rates of drug resistance. This has led to claims that DOTS-based TB control has failed in such settings. However, few studies have described the effect of a sustained and well-supported DOTS programme on TB incidence and drug resistance over a long period. We present long-term trends in incidence and drug resistance in rural Malawi.
  
  
  METHODS
  Karonga District in northern Malawi has an adult HIV prevalence of ≈ 10%. A research group, the Karonga Prevention Study, collaborates with the National Tuberculosis Programme to support core TB control activities. Bacteriological, demographic and clinical (including HIV status) information from all patients starting TB treatment in the District have been recorded since 1988. During that period isolates from each culture-positive TB patient were exported for drug sensitivity testing. Antiretroviral therapy (ART) has been widely available since 2005.
  
  
  RESULTS
  Incidence of new smear-positive adult TB peaked at 124/100,000/year in the mid-90 s, but has since fallen to 87/100,000/year. Drug sensitivity information was available for 95% (3132/3307) of all culture-positive cases. Initial resistance to isoniazid was around 6% with no evidence of an increase. Fewer than 1% of episodes involved a multi-drug resistant strain.
  
  
  CONCLUSIONS
  In this setting with a generalised HIV epidemic and medium TB burden, a well-supported DOTS programme enhanced by routine culture and drug sensitivity testing may well have reduced TB incidence and maintained drug resistance at low levels.
authors.affiliation: Karonga Prevention Study, Chilumba, Malawi.
authors.forename: Sebastian M
authors.initials: SM
authors.lastname: Mboma
authors.forename: Rein M G J
authors.initials: RM
authors.lastname: Houben
authors.forename: Judith R
authors.initials: JR
authors.lastname: Glynn
authors.forename: Lifted
authors.initials: L
authors.lastname: Sichali
authors.forename: Francis
authors.initials: F
authors.lastname: Drobniewski
authors.forename: James
authors.initials: J
authors.lastname: Mpunga
authors.forename: Paul E M
authors.initials: PE
authors.lastname: Fine
authors.forename: Neil
authors.initials: N
authors.lastname: French
authors.forename: Amelia C
authors.initials: AC
authors.lastname: Crampin
mesh_terms: D003140:Communicable Disease Control / Q000379:methods / Q000706:statistics & numerical data*; D023801:Directly Observed Therapy; D018432:Drug Resistance, Multiple / Q000502:physiology*; D015658:HIV Infections / Q000150:complications / Q000453:epidemiology*; D006801:Humans; D015994:Incidence; D008295:Malawi / Q000453:epidemiology; D015995:Prevalence; D016896:Treatment Outcome; D014376:Tuberculosis / Q000188:drug therapy* / Q000453:epidemiology* / Q000209:etiology