Leprosy Persists in High-burden Nations despite Progress
WHO Flags Treatment Access as Key to Ending Leprosy
Geneva: India, Brazil and Indonesia have consistently accounted for the majority of new leprosy cases in recent years, together representing around four-fifths of global detections, according to data cited by the World Health Organization (WHO) on Wednesday as it marked renewed international commitments ahead of World Leprosy Day on 25 January.
WHO said 172,717 new leprosy cases were reported globally in 2024 by 188 countries, areas and territories, even as 55 reporting jurisdictions recorded zero cases. The disease burden remains geographically concentrated, with the highest caseloads reported from South-East Asia, Africa and Latin America, reflecting long-standing endemic patterns.
The United Nations health agency said access to treatment remains central to global efforts to eliminate leprosy, a chronic infectious disease caused by Mycobacterium leprae. The disease affects the skin and peripheral nerves and can also involve the mucosa of the upper respiratory tract and the eyes. Transmission occurs through droplets from the nose and mouth during prolonged, close contact with untreated cases and does not occur through casual contact such as touching, sharing food or sitting together. A person stops being infectious once treatment begins.
Leprosy is curable through multidrug therapy (MDT), but untreated cases can lead to progressive and permanent disability. WHO notes that symptoms may appear within a year of infection or take as long as 20 years to develop, complicating early detection efforts. Diagnosis is based on clinical signs such as loss of sensation in skin patches, thickened peripheral nerves or laboratory confirmation of the bacteria. For treatment purposes, cases are classified as paucibacillary or multibacillary, depending on disease severity and bacterial load.
WHO surveillance data show that late diagnosis continues to pose a major challenge. More than 9,000 new cases worldwide were diagnosed with Grade-2 disability, meaning visible deformity at the time of diagnosis. Health experts regard this indicator as a critical measure of delayed detection, as early diagnosis and prompt treatment can prevent nerve damage and lifelong impairment. WHO also reported continued detection of leprosy among children, which is widely considered evidence of ongoing community transmission.
Global prevalence has declined substantially over the past two decades and remains below the former elimination benchmark of one case per 10,000 population. However, WHO officials emphasised that this threshold does not equate to interruption of transmission, which is now the stated objective under the Global Leprosy Strategy 2021–2030 and the broader Neglected Tropical Diseases (NTD) Roadmap 2021–2030.
Under these frameworks, WHO has shifted focus from reducing prevalence to achieving measurable declines in new case detection, childhood infections and disability rates. The strategy prioritises early diagnosis, systematic contact screening, expansion of preventive chemotherapy, including single-dose rifampicin for post-exposure prophylaxis, and measures to mitigate stigma and discrimination, which WHO identifies as persistent barriers to timely care.
WHO also confirmed that it has extended its long-standing partnership with pharmaceutical company Novartis through a new memorandum of understanding covering 2026–2030. The agreement ensures continued free global supply of MDT, consisting of rifampicin, dapsone and clofazimine, and includes funding support for procurement and distribution of preventive medicines. WHO recommends six months of MDT for paucibacillary cases and 12 months for multibacillary cases.
Dr Jeremy Farrar, WHO Assistant Director-General for Health Promotion, Disease Prevention and Care, said sustained collaboration had contributed to reductions in disease burden in several countries. Novartis said it would continue supplying medicines under the renewed agreement.
WHO Goodwill Ambassador for Leprosy Elimination Yohei Sasakawa, marking 25 years in the role, said discrimination against people affected by leprosy remains widespread, including in employment, education and family life, and often persists after medical treatment has ended.
Public health specialists note that while medicine supply is largely secured through donation programmes, elimination efforts are increasingly constrained by uneven surveillance capacity, diagnostic delays, gaps in access to health services in remote or marginalised communities, and persistent stigma that discourages early reporting of symptoms. Some experts caution that official case counts may understate the true burden, as undiagnosed and unreported cases are likely to remain in endemic settings.
As countries work toward WHO’s 2030 elimination targets, leprosy’s trajectory mirrors that of several other neglected tropical diseases: declining prevalence globally but continued transmission in a limited number of high-burden countries, where progress depends less on drug availability than on early detection, sustained financing and integration of disease control into general health systems.
– global bihari bureau
