South Africa is set to miss the 2030 End TB targets, a new model finds

South Africa carries one of the world's heaviest tuberculosis burdens, and a modelling study published on 18 August concludes it is unlikely to hit the global 2030 targets — while pointing precisely at the lever most likely to move the numbers [s1]. The World Health Organization's End TB strategy calls for an 80% reduction in TB incidence and a 90% reduction in TB mortality between 2015 and 2030 [s1]. The analysis projects South Africa will fall well short of both.

What the model projects

The researchers adapted an existing mathematical model of TB and HIV in South Africa, a coupling that matters because the two epidemics are so tightly linked there [s1]. Rather than produce a single forecast, they built in uncertainty deliberately: prior distributions were specified for 27 model parameters judged both highly uncertain and potentially important in driving future TB dynamics [s1]. Latin Hypercube Sampling then drew 1,000 parameter combinations from those distributions, and the model was projected forward to 2040 for each [s1].

The central results are sobering. Adult TB incidence was projected to decline by 46% (95% uncertainty interval 17-69%) by 2030 relative to 2015, and mortality by 54% (95% UI 21-84%) [s1]. Both fall short of the 80% and 90% milestones — and the wide uncertainty intervals, which at the low end reach declines of just 17% and 21%, show how much still hangs on factors that are not yet settled.

Which levers matter most

The more useful part of the study is not the shortfall but the ranking of what drives it. The team calculated partial rank correlation coefficients (PRCCs) linking each parameter to average adult TB incidence and mortality over 2025-2040 — a way of asking which uncertainties, if resolved favourably, would bend the curve furthest [s1].

The single most influential factor was the scale-up of microbiological testing in people with symptoms through near-point-of-care and tongue-swab (NPOC/TS) testing, with a PRCC of -0.67 against future incidence [s1]. The negative sign means more testing drives incidence down. Next came reductions in social contact rates that persisted after COVID-19 (PRCC -0.61), then the probability of sputum testing in symptomatic people in the absence of the newer NPOC/TS tools (PRCC -0.39), and the efficacy of TB preventive therapy (PRCC -0.35) [s1]. The predictors of mortality were similar [s1].

Why testing tops the list

That ordering is a message to programme planners. Two of the top four levers concern the same thing: finding TB in people who already have symptoms, faster and more reliably. Near-point-of-care and tongue-swab assays are attractive precisely because they promise to catch cases that current sputum-based pathways miss or delay, and the model suggests that closing that diagnostic gap does more to reduce transmission than most alternatives on the table [s1].

The prominence of post-COVID reductions in social contact is more ambiguous. It reflects a real epidemiological signal — mixing patterns changed during the pandemic and may not have fully reverted — but it is not a policy lever a TB programme can pull, which is part of why the authors distinguish between policy-changeable and external factors in framing their question [s1]. That distinction is the point of the exercise: to separate the drivers a health system can act on from those it can only hope for.

The honest conclusion

The study does not sugar-coat the destination. Its conclusion is that increasing testing among people with TB symptoms, including through new NPOC/TS technologies, "is likely to have the largest impact on progress towards End TB goals in South Africa, though attainment by 2030 is unlikely" [s1].

That combination — a clear miss on the headline targets, paired with a clear priority for narrowing it — is arguably the most useful thing a model can offer a national programme at this stage. The 2030 milestones were always aspirational, and a projected 46% fall in incidence and 54% fall in mortality would still represent substantial progress against a disease that remains a leading infectious killer in the country [s1]. The value of the analysis is in telling health authorities where the next rand of TB spending buys the most: at the point of diagnosis, in symptomatic people who are not currently being tested quickly enough.

For a country whose TB and HIV epidemics are so entwined, the framing also carries a quieter implication. A model that has to represent both diseases to forecast one is a reminder that progress on TB in South Africa cannot be planned in isolation from the HIV programmes that shape who becomes ill and how severely [s1]. The targets may be missed, but the study makes the path to doing better unusually concrete.

Sources

• Towards ending tuberculosis in South Africa: an uncertainty analysis of the programmes and factors most critical to future declines — Global Health Action, 2026-08-18