XACT-19 mission

1

To evaluate whether targeted community-based active case finding (ACF) in peri-urban high TB prevalence communities using computer-aided detection (CAD)-based triage testing, when used in tandem with Xpert, is feasible, has an improved TB yield, and is more cost-effective when compared to a Xpert alone strategy in symptomatic and/or asymptomatic persons.

2
To determine the value of screening for COVID-19 during TB-orientated ACF in peri-urban high TB prevalence communities.
3
To explore the accuracy of novel urine- and blood-based screening tests for TB and COVID-19 during community-based ACF in symptomatic and/or asymptomatic persons.

Aims

  1. To determine the adjunctive role of CAD in Xpert orientated community-based ACF for TB by rapidly questionnaire screening ~55 000 persons in high TB prevalence populations and randomising high-risk persons to targeted screening with a combined CAD followed by Xpert strategy versus Xpert-only strategy.
  2. To investigate the utility of CAD as a TB exclusion (screening) test in ~20 000 asymptomatic HIV-uninfected persons in a high TB prevalence peri-urban setting.
  3. To determine the feasibility and pick-up rate of screening ~1 500 persons for COVID-19 during TB-orientated ACF in peri-urban high TB prevalence communities.
  4. To evaluate the utility of alternative nascent urine- and blood-based screening technologies for community-based ACF for TB and COVID-19.

Outcome measures

Primary
Time to detection of microbiologically proven TB cases in each arm by 60-days.

Secondary 
Feasibility of the CAD + Xpert strategy, infectious cases detected, time-specific proportion of TB treatment initiation, yield of TB positive contacts, transmission and disease burden impact, TB middleware/dashboard design requirement, feasibility of COVID-19 screening.

Economic
Cost effectiveness of CAD + Xpert strategy, cost effectiveness of ACF compared to passive case finding (PCF), Cost effectiveness considering DR-TB and HIV prevention.