Chile Eliminates Leprosy, Sets Regional Benchmark

Chile became the first country in the Americas to achieve verified leprosy elimination, following decades of mandatory surveillance and coordination with PAHO and WHO. The milestone underscores the importance of regulatory continuity, primary care capacity, and stable pharmaceutical supply chains for countries such as Mexico that continue to manage active cases.

Chile has become the first country in the Americas to achieve verification of leprosy elimination after more than three decades without local transmission and sustained disease surveillance. The milestone was confirmed following a review by an independent expert panel convened by the Pan American Health Organization (PAHO), in partnership with the World Health Organization (WHO).

Health authorities say the achievement reflects long-term political commitment, mandatory case notification efforts, and continued clinical preparedness, even as case numbers fell to zero domestically.

“A major challenge, when you reach this level of elimination, is maintaining awareness of neglected diseases like leprosy,” says Patricia Contreras, Head of the Department of Communicable Diseases, Chile’s Ministry of Health. “Even if we see very few cases — or none at all — we must be prepared to recognize, remember, and identify a case, and have the capacity needed to respond and provide holistic care.”

From Control to Verified Elimination

Leprosy, also known as Hansen’s disease, remains one of the world’s oldest neglected tropical diseases. Globally, more than 120 countries report cases, with about 200,000 new infections detected annually. The Americas account for about 13% of reported cases worldwide.

Elimination is defined as zero new autochthonous cases for at least three consecutive years after transmission has been interrupted for at least five years. Chile has not recorded a locally acquired case in over 30 years.

Between 2012 and 2023, 47 cases were reported nationwide, all imported. Most occurred in men and were concentrated in the Metropolitan Region of Santiago. Each case triggered epidemiological investigation, laboratory confirmation, contact tracing, and follow-up.

“Imported cases do not represent a risk for the population because they are detected and treated,” says José Antonio Vergara, Public Health Physician in Southern Chile. “What matters is staying alert and making an early diagnosis to interrupt any possible chain of transmission.”

Unlike with diseases that fade from institutional focus as incidence declines, health professionals and laboratories in Chile are required to report confirmed and suspected cases to public health authorities. Officials say this preserved technical capacity and institutional memory, even as most clinicians would not encounter a case during their careers.

Leprosy spreads through prolonged, close contact with an untreated person, primarily via respiratory droplets. It is not transmitted through casual contact such as handshakes or shared meals. Once multidrug therapy begins, patients are no longer contagious.

Since 1995, the PAHO has supplied multidrug therapy free of charge to member states in the Americas. Sustained access to treatment has been central to preventing disability and interrupting transmission.

The verification process required Chile to demonstrate that its surveillance systems, case management protocols, and response capacity could be sustained in a low-incidence context. After reviewing epidemiological trends and operational readiness, the expert panel concluded that the country met the criteria and had the institutional capacity to maintain elimination.

Regional Context: Progress and Persistent Transmission

Chile’s milestone comes as other countries in the region continue to manage active transmission.

In Mexico, the Ministry of Health operates a National Leprosy Elimination Program that provides free combination therapy across all 32 states. The program aims to train healthcare personnel, screen at least 90% of patient contacts, ensure uninterrupted treatment, and reduce prevalence. Mexico closed 2023 with about 300 cases, of which 234 were classified as multibacillary and 66 as paucibacillary.

Roughly 200 new cases are reported annually in Mexico, with Sinaloa, Guanajuato, Guerrero, and Nayarit recording the highest incidence. Health authorities stress that early diagnosis can prevent disability and allow patients to remain economically active throughout treatment.

According to global data compiled by the WHO, 174,087 new cases were recorded worldwide in 2022, with 67,657 occurring in women. Studies indicate that women often face delays in diagnosis due to lower awareness and limited access to care.

The PAHO reported in late 2025 that Chile had formally requested verification for elimination of leprosy as part of a broader regional initiative to eliminate more than 30 communicable diseases and related conditions by 2030. The request was reviewed alongside other regional advances, including malaria-free certification for Suriname and progress in eliminating mother-to-child transmission of HIV in several countries.

Jarbas Barbosa, Director, PAHO, said in a year-end message that the organization’s Strategic Plan 2026–2031 will prioritize measurable targets, including the elimination of selected communicable diseases. The plan follows a year in which PAHO’s epidemiological teams analyzed more than 1.8 million health signals and identified 128 public health events, underscoring the need for continued surveillance capacity across the region.

Global Commitments and Innovation

Chile’s achievement also aligns with renewed global commitments to eliminate leprosy by 2030.

In January 2026, Novartis announced it would extend its partnership with the WHO to provide multidrug therapy to approximately 1 million additional people affected by leprosy through the end of the decade. The company has worked with WHO for 25 years on a not-for-profit basis, donating more than 70 million treatment blister packs since 2000, valued at about US$124 million.

Reported global cases have declined by 96% since 1980, but around 200,000 new infections are still detected each year. An estimated 2 million to 3 million people continue to live with disabilities related to delayed diagnosis and stigma.

The renewed agreement focuses on early treatment, disability prevention, and stigma reduction. Prevention strategies have also evolved. The Leprosy Post-Exposure Prophylaxis program, launched in 2014 and implemented in seven countries, evaluated preventive treatment for close contacts of newly diagnosed patients. Evidence from the initiative informed WHO’s 2018 guidelines on diagnosis, treatment, and prevention.

Technological innovation has entered the field. In 2019, the Novartis Foundation announced a collaboration with Microsoft and Brazil’s Oswaldo Cruz Foundation to explore AI tools capable of analyzing images of skin lesions to support screening and diagnosis in settings with limited specialist access.

The WHO’s global strategy, “Towards Zero Leprosy” for 2021–2030, aligns with the Neglected Tropical Diseases Road Map and sets out pillars including integrated country-led road maps, expanded prevention, improved management to prevent disability, and actions to address stigma and safeguard human rights.

Historical Lessons and Institutional Memory

Chile’s path to elimination includes a complex history. Leprosy reached Rapa Nui, also known as Easter Island, in 1889, likely introduced from Tahiti. Overcrowding and limited sanitation facilitated spread. By 1976, screening identified 460 cases among 2,800 residents, representing more than 15% of the population. Isolation policies and a leprosarium marked that period.

Advances in treatment and changes in care models gradually replaced segregation with community reintegration. By 1995, the last known case on Rapa Nui had been identified and treated.

Health officials say those historical experiences reinforced the importance of early detection, respectful care, and long-term follow-up. Chile’s current framework guarantees access to treatment and disability services for all individuals, including migrants, and emphasizes confidentiality.

“Chile is committed to ensuring that any diagnosed cases receive long-term follow-up, that potential sequelae are treated, and that no one is left with a disability we could prevent,” Contreras says.