Illicit Drug Use, Tuberculosis
Conditions
Brief summary
Tuberculosis (TB) is the leading infectious disease killer globally and leading cause of death in persons with HIV. The most effective way to reduce TB incidence and mortality is to interrupt transmission. This requires finding and treating individuals with TB disease early, including those with subclinical disease. Molecular epidemiologic studies and mathematical models have shown that the primary approach to case finding-household contact tracing-identifies only 8-19% of transmissions in high TB and TB/HIV burden settings. Thus there is a clear need to identify new groups and settings where TB transmission occurs. Spatial clustering of individuals with higher rates of progression from infection to disease, such as those with HIV and malnourishment, can also form transmission hotspots. Illicit drug (i.e., methamphetamines, crack/cocaine, opiates) users have higher TB infection prevalence and disease incidence compared to non-users, likely due to significant within-group transmission and/or clustered vulnerability. Increased transmission among people who use illicit drugs (PWUD) could result from creation of more efficient TB transmitters, increased close contact among transmitters, increased rates of primary progression from infection to disease among contacts, or a combination. Interrogation of illicit drug user networks for TB transmission, therefore, holds great potential as a target for early case identification and linkage to treatment, with potential benefit for halting transmission to the broader population.
Detailed description
A cross-sectional, observational study design using respondent driven sampling (RDS) will be used for this research study. In Aim 1, individuals will be recruited who currently use meth and/or Mandrax to assess TB exposure, incipient TB prevalence, and TB disease prevalence in the network. RDS will be used to seek out 750 meth/Mandrax users. Initial seeds (N=4) will be individuals from the investigator's current R01, the Tuberculosis treatment outcomes and alcohol use study (TRUST) cohort who have had active pulmonary TB disease in the prior 1-2 years and report current meth/Mandrax use. For Aim 2, individuals from Aim 1 identified to have possible TB disease will be screened and enrolled to estimate the proportion that reflect recent transmission via genotyping and social epidemiologic links. In Aim 3, the investigators will examine physiologic factors that may make PWUD more efficient TB transmitters. 50 PWUD participants from Aim 2 will be recruited who have active, untreated pulmonary TB and 50 individuals with active, untreated pulmonary TB who do not use meth/Mandrax, matched on age and gender will be recruited
Interventions
BEHAVIORALSmoked illicit drug use
The exposure of interest is current smoked illicit drug use, particularly methamphetamine and/or methaqualones
Sponsors
University of Stellenbosch
Desmond Tutu HIV Foundation
Boston University
Medical Research Council, South Africa
National Institute of Allergy and Infectious Diseases (NIAID)
Boston Medical Center
Study design
Observational model
CASE_CONTROL
Time perspective
CROSS_SECTIONAL
Eligibility
Sex/Gender
ALL
Age
15 Years to No maximum
Healthy volunteers
No
Inclusion criteria
Participants must be/have the following general inclusion criteria: 1. at least 15 years old 2. resident of the study community 3. intact mental status at enrollment (i.e., no acute intoxication) 4. provide written, informed consent to participate in the study if ≥18 years or written assent and parental consent if \<18 years. 5. agree to comply with all study requirements, including provision of contact information and study appointments attendance And for Aim 1: 1. self-reported meth or Mandrax use in the past month 2. urine drug screen positive for meth and/or Mandrax 3. all participants other than the seeds must also have evidence that they have been recruited by a peer (the coupon) For Aim 2 participants must meet all general inclusion criteria and the inclusion criteria from Aim 1 (meth/Mandrax use) and: (1) Have evidence of active TB disease on Xpert Ultra from their Aim 1 visit testing or report a recent TB diagnosis (within the past month) For Aim 3 Arm 1 participants must meet all general inclusion criteria and the criteria under Aim 1 and Aim 2 (active illicit drug use and active TB) And
Exclusion criteria
1. No current pregnancy by urine pregnancy test 2. Not yet started on TB medication For Aim 3 Arm 2 patients must meet all general inclusion criteria and the following inclusion criteria: 1. Attend the Worcester Community Day Clinic, the Empilisweni Clinic, or any other clinic and live in the general Worcester area 2. Have newly diagnosed TB And
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| TB disease prevalence | At baseline | Percentage of persons with TB disease based on results from Xpert Ultra and sputum culture |
| Incipient TB prevalence | At baseline | Percentage of persons with incipient TB based on host RNA signature |
| Proportion of active TB cases resulting from recent transmission within this network of PWUD | At baseline | Proportion of linked TB cases based on whole genome sequencing of the mycobacterium tuberculosis (Mtb) isolate and overlaying social epidemiological ties |
| Quantity of aerosolized Mtb in exhaled breath: amount of aerosolized Mtb exhaled in one hour | One hour | The amount of aerosolized Mtb exhaled in one hour in a specialized bio-aerosol capturing booth |
Countries
South Africa
Outcome results
None listed