Tuberculosis Screening in Paraguayan Prisons

Two diagnostic tools for TB screening in high risk groups need additional assessment: the AeoNose™, an 'electronic nose device' for breath sampling, and digital chest X-ray (CXR) with computer aided detection with CAD4TB® software. This study will systematically screen prisoners and its' employees for TB, test the diagnostic performance of AeoNose™ and CAD4TB (both individually and together) as a TB screening tool and and establish Mycobacterium tuberculosis epidemiology in Paraguayan prisons.

The aim of the World Health Organization (WHO) "End TB Strategy" is to end the global pandemic by 2035. To be able to succeed, better point-of-care (POC) tests are urgently needed to improve screening of high-risk populations. Prisons are recognized worldwide as high risk environments for the concentration, amplification and transmission of TB among prisoners and their communities outside. Paraguayan penal institutions are known to have very high incidence rates of active TB (3000-5000/100.000, according to Paraguayan Ministry of Justice). Two diagnostic tools for TB screening in high risk groups will be evaluated: the AeoNose™, an 'electronic nose device' for breath sampling, and digital chest X-ray (CXR) with computer aided detection with CAD4TB® software. This study will systematically screen prisoners and its' employees for TB, test the diagnostic performance of AeoNose™ and CAD4TB® and assess prison Mycobacterium tuberculosis epidemiology through several objectives: Objective: 1. Assessment of the sensitivity and specificity of the AeoNose™ and its utility for mass TB screening in high incidence settings. 2. Evaluation of the feasibility and utility of CAD4TB® digital CXR as a mass screening tool for TB. 3. Identification of factors that affect diagnostic accuracy of AeoNose™ and CAD4TB®. 4. Assessment of TB epidemiology in Paraguayan prisons and identification of mycobacterial strains.

Study design: Diagnostic cohort study. Study population: Detainees (PPL) of Paraguayan penal institutions as well as their employees. Nature and extent of the burden and risks associated with participation, benefit and group relatedness.

Individual burden: all participants will perform one visit with a medical doctor for medical history, physical exam, digital X-ray (with CAD4TB®) and AeoNose sampling. Participants will be offered voluntary HIV testing and counseling. In case of presumptive TB (estimated 20-30% of participants) two sputum samples will be taken, either spontaneous or saline-induced. One sample is tested with GeneXpert and the other with liquid mycobacterial culture. Cases of presumptive TB with both negative GeneXpert® and culture results will be followed-up after three and six months for repeat testing.

Eligibility Criteria:
Inclusion Criteria:

* All persons, either being a prisoner or employee, of the involved penal institutions after providing informed consent, including those with known active TB disease and/or currently on TB treatment

Exclusion Criteria:

* A potential participant who meets any of the following criteria will be excluded from participation in this study:

  1. Unable to exhale breath through the AeoNose™ during five minutes due to respiratory insufficiency
  2. Unable to stand in an upright position for the CXR
  3. Unable to communicate and comply with the instructions of the study team