After nearly 2,000 years of dread, isolation, and misunderstanding, the global campaign against leprosy is nearing what health officials call its most critical phase. Ahead of World Leprosy Day (January 25), the World Health Organisation (WHO) has emphasised that free treatment, along with a renewed focus on prevention, has the potential to finally stop the illness from spreading. 

Leprosy is caused by the slow-growing bacteria Mycobacterium leprae. It primarily affects the skin and nerves. If untreated, it might result in permanent disability. The science is no longer the issue. For decades, a simple mix of tablets known as multidrug treatment (MDT) has effectively cured the condition. 

The harder battle has been social. 

"In many places, leprosy still brings a form of social death," said Mr Yohei Sasakawa, WHO Goodwill Ambassador for Leprosy Elimination, who is celebrating 25 years in the sector. Even after being cured, he remarked that victims face "forced divorce, lost educational opportunities, and unfair dismissal," as well as the "unending pain of social exclusion." 

This contrast, between an accessible biological treatment and a persisting societal stigma, serves as the foundation for the next phase of the global response. 

From healing patients to protecting communities 

Since 2000, WHO and pharmaceutical giant Novartis have collaborated to deliver MDT and the medication clofazimine free of charge to every leprosy patient worldwide. It is still one of the longest-running drug donation programs in global health. Over the last 25 years, millions of people have been treated, including those in the most distant areas. 

The influence is evident. Of the 188 nations and territories that reported data to WHO in 2024, 55 had no new cases. Nonetheless, the job remains unfinished. The world found 172,717 new cases last year, with the majority concentrated in a few nations. 

WHO and Novartis have extended their relationship for another five years, from 2026 to 2030, to address this "last mile" issue. The new agreement maintains the free supply of MDT while introducing a critical tool: single-dose rifampicin for post-exposure prophylaxis, known as SDR-PEP. 

Simply said, it changes the fight's rules 

"Earlier, we treated the fire," explained a senior WHO official. "Now, we are also protecting the surrounding houses with fire retardant." SDR-PEP is a single tablet administered to a patient's close contacts – family members, neighbours, or others they have come into contact with – to prevent the infection from spreading further. 

Dr Jeremy Farrar, WHO Assistant Director-General, described the alliance as "foundational" for efforts against leprosy. " Free access to treatment has transformed millions of lives and moved us closer to a world free from this ancient disease," he stated. He added that the next phase will demonstrate "what global solidarity can achieve when science and equity align". 

Why stigma still matters

The theme for this year's World Leprosy Day, "Leprosy is curable; the real challenge is stigma," underscores a growing recognition that medications alone are insufficient. Even cured patients may experience nerve damage, acute inflammatory episodes known as lepra responses, or apparent disabilities that perpetuate discrimination. 

Dr Lutz Hegemann, President of Global Health at Novartis, stated that the company's commitment remains steadfast. "We have reached millions of patients together with WHO, and we are committed to going further to pursue a world free of leprosy." 

Leprosy is also one of the neglected tropical diseases (NTDs) designated for eradication under WHO's 2021-2030 roadmap. That strategy incorporates early detection, preventive medications such as SDR-PEP, and proactive attempts to combat discrimination. 

In 2026, science has already provided the cure. Whether the world can now treat prejudice will determine if one of humanity's oldest diseases is finally eradicated.