If you trace contacts and have nothing to provide, is contact tracing really necessary?
Leprosy has not been conquered — it has merely become inconvenient to remember. A new multi-country study reveals that as case numbers fall in low-endemic nations, the political will, funding, and medical expertise needed to prevent transmission quietly dissolve, leaving the most vulnerable populations exposed to a disease that still causes permanent disability in millions. The paradox of progress is that proximity to elimination can itself become a barrier to it, as governments turn their attention elsewhere and the infrastructure of care quietly collapses.
- Roughly 200,000 new leprosy cases emerge each year globally — a figure that has barely moved in two decades, even as most countries have declared the disease effectively defeated.
- In Afghanistan, Bolivia, Colombia, Pakistan, Senegal, and Togo, researchers found that declining case numbers trigger a dangerous cycle: funding disappears, medical schools stop teaching diagnosis, and policymakers who have never seen the disease cannot be persuaded to prioritize it.
- A proven preventive tool — single-dose rifampicin, shown to cut transmission risk by up to 57 percent — sits largely unused because the drug is unregistered for leprosy prevention, pharmaceutical companies have no incentive to supply it at small scale, and existing stocks are reserved for tuberculosis treatment.
- Stigma deepens the crisis: patients conceal their illness, contacts refuse identification, and in some communities leprosy is understood as a curse, making the contact tracing that prevention depends upon nearly impossible to conduct.
- Researchers point toward integration — bundling leprosy screening with other skin disease programs, embedding prevention into existing health infrastructure, and linking advocacy to the already-funded fight against tuberculosis — as the most viable path through the structural trap.
- Without deliberate government leadership and a secure rifampicin supply chain, the window to interrupt transmission in these settings is closing, and the populations most at risk remain the poorest and most remote — precisely those hardest to reach.
Leprosy has not disappeared. Roughly 200,000 new cases still emerge each year, a number that has barely shifted in two decades. Yet most countries have declared victory and moved on — and that declaration, researchers now warn, is itself part of the problem.
A study drawing on interviews with programme coordinators, policymakers, practitioners, and experts across six low-endemic countries — Afghanistan, Bolivia, Colombia, Pakistan, Senegal, and Togo — exposes a structural trap. As case numbers fall, governments lose interest. Funding dries up. Medical schools stop teaching doctors to recognize the disease. Expertise evaporates. And the disease persists, quietly, in the remote and impoverished communities where it has always been hardest to reach.
At the center of the study is a proven but underused intervention: single-dose rifampicin given to the contacts of leprosy patients, which clinical trials show can reduce transmission risk by up to 57 percent. The WHO endorses it. The evidence supports it. But in low-endemic settings, the barriers are formidable. Rifampicin is not routinely available for leprosy prevention — pharmaceutical companies have little incentive to supply it at small scale, regulatory bodies have not registered it for this use, and in countries where tuberculosis is also present, existing stocks are reserved for TB treatment. One expert from Togo captured the ethical bind: if contact tracing cannot be followed by treatment, is there any point in tracing contacts at all?
Stigma compounds the structural failures. Leprosy is understood in some communities as a curse or a mark of moral failing. Patients conceal their illness. Contacts refuse to be identified. Female patients in certain cultural settings cannot be examined by male health workers, yet female health workers are scarce. The disease is rare enough to be overlooked institutionally, yet concentrated enough in specific pockets to cause lasting harm.
The researchers identified several routes forward. Integrating leprosy screening with programs targeting other neglected tropical diseases — bundling it with efforts against Buruli ulcer, yaws, or other skin conditions — can stretch limited resources and reduce the stigma of single-disease campaigns. Pakistan's partnership with primary eye care services, which trained leprosy ophthalmic technicians to extend screening through existing infrastructure, offered one model. Designating clear government focal points for leprosy control, and building advocacy that connects leprosy prevention to the already-prioritized fight against tuberculosis, emerged as essential strategies.
But the study's central argument is political as much as logistical. Low endemicity is not the same as no endemicity. The disease still causes permanent disability in an estimated three to four million people worldwide. The window to interrupt transmission in these settings is narrowing — and the populations most at risk are precisely those least visible to the systems meant to protect them.
Leprosy has not disappeared. Though most countries have declared victory over the disease, roughly 200,000 new cases still emerge each year globally—a number that has barely budged in two decades. The paradox is this: as endemicity drops and countries move closer to elimination, the very infrastructure meant to stop transmission begins to crumble. A new study of six low-endemic countries reveals why.
Researchers conducted in-depth interviews with 12 key stakeholders—programme coordinators, policymakers, medical practitioners, and leprosy experts—across Afghanistan, Bolivia, Colombia, Pakistan, Senegal, and Togo. Their findings expose a structural trap. When case numbers fall, governments lose interest. Funding dries up. Medical schools stop teaching doctors how to recognize the disease. The expertise vanishes. And yet the disease persists, especially in remote, impoverished areas where it has always been hardest to reach.
The study focused on a proven intervention: single-dose rifampicin given to contacts of leprosy patients. Clinical trials have shown this approach reduces transmission risk by up to 57 percent. The WHO endorses it. Multiple countries have demonstrated it works. But in low-endemic settings, the barriers to routine implementation are formidable and interconnected. One participant, a programme coordinator from Colombia, described the bind plainly: "Policy makers can prioritize whether leprosy will be included and how much of those resources can be designated for leprosy. Some of them haven't even seen or heard of leprosy at all in their lives. And of course, this adds up to the problem of putting leprosy in the public health agenda."
Rifampicin itself became a flashpoint. The drug is essential for both leprosy prevention and tuberculosis treatment. Yet in low-endemic countries, it is not routinely available. Pharmaceutical companies have little incentive to manufacture it in quantities suitable for prevention in areas where case numbers are small. Regulatory authorities have not officially registered it for leprosy prevention. And where TB is also present—which is true in most of these countries—rifampicin supplies are reserved for TB treatment, leaving leprosy prevention programs dependent on charity. One expert from Togo expressed the ethical dilemma bluntly: "Contact tracing and PEP should go hand in hand. Because if you go and trace contacts and then you don't have anything to provide, is it really necessary to go for contact tracing?"
The human dimension compounds these structural problems. Leprosy carries profound stigma in many communities. Patients fear disclosure. Contacts fear being identified. In some settings, the disease is understood as a curse, a mark of sin or criminality. Healthcare workers in remote areas often lack training to recognize it. Female patients in certain cultural contexts cannot be examined by male health workers, yet female health workers are scarce. The disease is rare enough that it gets overlooked, yet common enough in pockets to cause real harm.
The researchers identified several pathways forward. Integration with other neglected tropical disease programs—bundling leprosy screening with efforts against Buruli ulcer, yaws, or other skin conditions—can stretch limited resources and reduce stigma by avoiding single-disease campaigns. Pakistan's collaboration with primary eye care services, creating "leprosy ophthalmic technicians," extended screening to remote areas through existing infrastructure. Establishing clear focal points within government—dedicated individuals responsible for leprosy control—proved essential for sustained commitment. And community-based screening events, when designed to address multiple skin diseases at once, can build trust and reduce the fear of being singled out.
But none of this works without political will. The study makes clear that low-endemic countries need repositioning of leprosy as a public health priority, not because case numbers are high, but because the disease still causes permanent disability—affecting an estimated 3 to 4 million people globally—and because the window to interrupt transmission in these settings is closing. Success requires government leadership, cross-stakeholder coordination both within and across borders, and a secure supply chain for rifampicin. It requires training healthcare workers in places where leprosy is rare. It requires advocacy that connects leprosy control to the already-prioritized fight against tuberculosis. Most fundamentally, it requires acknowledging that low endemicity is not the same as no endemicity, and that the poorest, most remote populations—those hardest to reach—are precisely where the disease persists.
Citas Notables
Policy makers can prioritize whether leprosy will be included and how much resources can be designated for it. Some haven't even seen or heard of leprosy in their lives.— Colombia programme coordinator
Contact tracing and prevention should go hand in hand. If you trace contacts and then have nothing to provide, is contact tracing really necessary?— Togo programme coordinator
La Conversación del Hearth Otra perspectiva de la historia
Why does leprosy become harder to control as it becomes rarer?
Because rarity breeds invisibility. When a disease is common, governments fund it, doctors learn about it, supply chains exist for its medicines. When it becomes rare, all of that infrastructure starts to evaporate. The disease doesn't disappear—it just moves to the places that are hardest to reach and easiest to forget.
The study mentions rifampicin as a critical bottleneck. Why is a single drug so central to the whole problem?
Rifampicin is the only drug proven to prevent leprosy transmission in contacts. But it's also used for tuberculosis, which is far more common. In countries where both diseases exist, TB gets the rifampicin. Leprosy prevention gets nothing. And because leprosy is rare, pharmaceutical companies see no profit in making more. It's a market failure dressed up as a supply chain problem.
One quote in the study really struck me—about contact tracing without medicine being pointless. Is that actually true?
It's ethically true. If you find someone who's been exposed to leprosy and you have no drug to give them, you've just identified them as a contact in their community. You've created stigma without offering protection. That's why the researchers say contact tracing and prevention must go hand in hand. You can't do one without the other.
The study emphasizes integration with other disease programs. Does that actually work, or does leprosy just get buried?
It depends on how it's done. In Togo, integrating leprosy screening with Buruli ulcer and yaws screening actually increased government funding and awareness. But only because they were intentional about it—they didn't let leprosy disappear into a larger program. The key is clear leadership and dedicated focal points that keep leprosy visible even when it's bundled with other diseases.
What about the stigma angle? How much of this problem is cultural versus structural?
Both, inseparably. The structural problems—lack of funding, lack of expertise—make stigma worse because people have no access to treatment or prevention. And stigma makes the structural problems worse because patients won't disclose contacts, so case detection fails. Community-based screening events that address multiple skin diseases at once can break that cycle by removing the spotlight from leprosy alone.
If Pakistan has figured out how to do this, why haven't other countries copied them?
Pakistan is the only country in this study that achieved routine implementation of both active case detection and prevention. But their success came from specific choices—integrating with eye care, building focal points, sustained government commitment. Those choices can't be simply transplanted. Each country needs to adapt the approach to its own health system, its own geography, its own political reality. That's why the researchers emphasize local alignment of policy, not one-size-fits-all solutions.