Non-tuberculous mycobacteria (NTM) in Zambia: prevalence, clinical, radiological and microbiological characteristics

BMC Infect Dis. 2015 Nov 6:15:500. doi: 10.1186/s12879-015-1264-6.

Abstract

Background: Non-tuberculous mycobacteria (NTM) infection is an emerging health problem. We present here the Zambia-specific national level data of prevalence, symptomatic, radiological and microbiological characteristics of NTM, using results from a national Tuberculosis (TB) prevalence survey.

Methods: This was a cross-sectional study of the prevalence of NTM among adults aged 15 years and above, who were participants in a national TB prevalence survey. Participants who had either an abnormal chest x-ray or were symptomatic were considered presumptive TB cases and submitted sputum for smear and culture analysis. HIV testing was performed on an opt-out basis. Symptomatic NTM prevalence was estimated from individual level analysis.

Results: Of the 6,123 individuals with presumptive TB, 923 (15.1%) were found to have NTM, 13 (0.2%) were MTB/NTM co-infected and 338 (5.5%) were contaminated (indeterminate). The prevalence of symptomatic NTM was found to be 1,477/100,000 [95% CI 1010-1943]. Smear positivity, history of cough or chest pain and HIV positivity were risk factors for NTM.

Conclusion: This first study to estimate the national prevalence of NTM in Zambia indicates that the burden is high. The NTM occurrence in Zambia constitutes both a public health and ethical issue requiring action from health managers.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Coinfection / epidemiology
  • Cough / complications
  • Cough / etiology
  • Cross-Sectional Studies
  • Female
  • HIV Seropositivity
  • Humans
  • Lung / diagnostic imaging
  • Male
  • Middle Aged
  • Mycobacterium Infections, Nontuberculous / diagnostic imaging
  • Mycobacterium Infections, Nontuberculous / epidemiology*
  • Mycobacterium Infections, Nontuberculous / microbiology
  • Mycobacterium tuberculosis / isolation & purification
  • Mycobacterium tuberculosis / pathogenicity
  • Nontuberculous Mycobacteria / isolation & purification
  • Nontuberculous Mycobacteria / pathogenicity*
  • Prevalence
  • Radiography
  • Risk Factors
  • Sputum / microbiology
  • Tuberculosis / epidemiology
  • Tuberculosis / microbiology
  • Young Adult
  • Zambia / epidemiology