Phone screening after tuberculosis matched home visits overall, and missed recurrences

Finishing tuberculosis treatment is not the end of tuberculosis risk. Survivors face elevated recurrence, and their household contacts remain exposed. The question of how to follow them up is a resource question: home visits are effective and expensive, phone calls are cheap and might be enough.

TB Aftermath tested this directly in India, and the answer depends entirely on which population you ask about.

What the trial did

The trial enrolled 1,076 tuberculosis survivors — 537 in the phone-based screening group and 539 in the home-based screening group — and enumerated 3,309 contacts, 1,638 and 1,671 respectively, between January 2021 and September 2023 [s1].

In the 12-month post-treatment period, tuberculosis was detected in 75 (7%) tuberculosis survivors and 30 (1%) contacts [s1].

That 7% figure deserves to be read on its own. Seven per cent of people who completed tuberculosis treatment had tuberculosis again within a year [s1]. Whatever follow-up strategy is chosen, the case for having one is in that number.

The headline result

There were 41 events in the phone-based group (rate 1.19 [95% CI, 0.82–1.71]) against 64 in the home-based group (1.92 [1.37–2.45]), and non-inferiority was reached, with a rate difference of 0.73 (95% CI, 0.05–1.41) [s1].

Phone screening was non-inferior for detecting tuberculosis among survivors and their household contacts together [s1]. That is the composite the trial was designed around, and on it the cheaper strategy held up.

The result underneath it

Split the composite and it reverses for the group that matters most.

Among tuberculosis survivors, the recurrence detection rate was 4.36 (95% CI, 2.87–6.34) in the phone-based group against 8.00 (5.90–10.60) in the home-based group (P = 0.01) [s1].

Among contacts, detection rates were 0.61 (95% CI, 0.32–1.07) by phone and 0.70 (0.39–1.20) at home (P = 0.70) [s1].

Home visiting detected roughly twice the recurrence rate in survivors, and the difference was statistically significant [s1]. In contacts, the two approaches were indistinguishable [s1].

The composite held because contacts vastly outnumber survivors — 3,309 against 1,076 — so a large group where the strategies perform identically dilutes a smaller group where they do not [s1].

This is a general hazard of composite endpoints, and this trial is an unusually clean example. Non-inferiority on the combined measure is a true statement about the combined measure. It is not a statement about survivors, and a programme that adopted phone screening on the strength of the headline would be applying it to the population where it demonstrably underperforms.

To the authors' credit, their interpretation says so: countries with a high burden of recurrence should consider home-based screening among tuberculosis survivors [s1].

Why phone screening might miss recurrence

The trial does not establish a mechanism, but the asymmetry is suggestive. Detecting recurrence in a survivor requires eliciting symptoms from someone who has had tuberculosis before, may minimise early signs, and may not want to return to treatment. A home visit produces observation — weight, breathing, living conditions — and a sample. A call produces self-report.

Screening contacts is a different task, closer to case-finding among people who mostly do not have the disease, and self-report may lose less there.

What it costs

The trial does not report a cost analysis in the material reviewed here, and the case for phone screening is entirely economic. Home visits in a high-burden country at national scale require staff and travel; calls do not.

The honest framing is a trade, not an equivalence: phone screening is cheaper and detects roughly half the recurrences in survivors [s1]. Whether that trade is acceptable depends on programme budgets and on how much recurrence costs when it is found late — a calculation this trial informs but does not make.

The wider context

Follow-up sits alongside the other lever on tuberculosis burden, which is making treatment itself shorter and more completable. A 2026 trial in South Africa found a six-month strategy for rifampicin-resistant tuberculosis non-inferior to standard of care, with a successful outcome in 86.1% against 86.0% and an adjusted risk difference of −0.2 percentage points (95% CI, −6.9 to 6.5; P = 0.001 for non-inferiority) [s2].

Shorter treatment and cheaper follow-up address the same underlying problem — that tuberculosis care is long, and people fall out of it — from opposite ends. TB Aftermath was funded by the US National Institute of Allergy and Infectious Diseases [s1].

What to watch

Whether Indian and other high-burden national programmes adopt a split strategy: calls for contacts, visits for survivors, which is what the disaggregated data supports [s1]. And whether a cost-effectiveness analysis puts a number on the recurrences phone screening misses.

This article describes published trial results. It is not medical advice.