Introduction
Leprosy is a chronic infectious disease caused by Mycobacterium leprae, an acid-fast, rod-shaped bacillus. The disease mainly affects the skin, the peripheral nerves, mucosa of the upper respiratory tract, and the eyes. Leprosy is curable and treatment in the early stages can prevent disability.
Brief history and treatment
Leprosy is an age-old disease, described in the literature of ancient civilizations. Throughout history, people afflicted have often been ostracized by their communities and families.
Although leprosy was managed differently in the past, the first breakthrough occurred in the 1940s with the development of the medicine dapsone. The duration of treatment lasted many years, often a lifetime, making compliance difficult. In the 1960s, M. leprae started to develop resistance to dapsone, the only known anti-leprosy medicine at that time. In the early 1960s, rifampicin and clofazimine were discovered and subsequently added to the treatment regimen, which was later labelled as multidrug therapy (MDT).
In 1981, WHO recommended MDT. The currently recommended MDT regimen consists of medicines: dapsone, rifampicin and clofazimine. This treatment lasts six months for pauci-bacillary and 12 months for multi-bacillary cases. MDT kills the pathogen and cures the patient.
Since 1981 WHO has provided MDT free of cost. Free MDT was initially funded by The Nippon Foundation, and since 2000 it is donated through an agreement with Novartis until 2025.
More than 16 million leprosy patients have been treated with MDT over the past 20 years. A general reduction in new cases, though gradual is observed in several countries. The new cases reduced to 202 256 in 2019. Several countries reported less number cases, including 45 countries reported zero leprosy cases.
WHO response
In 2018, WHO reviewed available evidence on key issues related to elimination of leprosy and developed ‘WHO guidelines for the diagnosis, treatment and prevention of leprosy 2018’, recommending three-drug regimen (rifampicin, dapsone and clofazimine) to both pauci-bacillary and multibacillary types of leprosy. The guidelines also introduced prevention of leprosy through single dose of rifampicin for eligible familial and social contacts.
After a detailed consultations with countries, experts in leprosy, partners and persons affected by leprosy WHO released ‘Towards Zero Leprosy -– Global Leprosy (Hansen’s disease) Strategy 2021‒-2030' in line with NTD road map 2030 in April 2021.
The strategy is published in English and translated versions into French, Portuguese, Spanish and Russian languages are made available for reaching wider global audience.
TOWARDS ZERO LEPROSY - GLOBAL LEPROSY (HANSEN’S DISEASE) STRATEGY 2021–2030
Long term vision
Zero leprosy: zero infection and disease, zero disability, zero stigma and discrimination
Goal
Elimination of leprosy (defined as interruption of transmission)
Global targets for 2030
- 120 countries with zero new autochthonous cases
- 70% reduction in annual number of new cases detected
- 90% reduction in rate per million population of new cases with grade-2 disability (G2D)
- 90% reduction in rate per million children of new child cases with leprosy
Strategic pillars and key components
1: Implement integrated, country-owned zero leprosy roadmaps in all endemic countries
- Political commitment with adequate resources for leprosy in integrated context
- National partnerships for zero leprosy and zero leprosy roadmaps engaging all stakeholders
- Capacity building in the healthcare system for quality services
- Effective surveillance and improved data management systems
- Monitoring of antimicrobial resistance (AMR) and adverse drug reactions
2: Scale up leprosy prevention alongside integrated active case detection
- Contact tracing for all new cases
- Preventive chemotherapy scaled up
- Integrated active case-finding in targeted populations
- Existing and potential new vaccines
3: Manage leprosy and its complications and prevent new disability
- Early case detection, accurate diagnosis and prompt treatment
- Access to comprehensive, well-organized referral facilities
- Diagnosis and management of leprosy reactions, neuritis and disabilities
- Monitoring, support and training in self-care
- Mental well-being through psychological first aid and therapeutic counselling
4: Combat stigma and ensure human rights are respected
- Adoption of Principles and Guidelines for elimination of discrimination against persons affected by leprosy and their family members
- Inclusion of organizations and networks of persons affected by leprosy
- Amendment of discriminatory laws
- Interventions and processes to reduce and monitor leprosy-related stigma in communities
- Access to social support and rehabilitation
Research
The strategy includes a set of research priorities of key importance for this strategic period. Global and national investment in research is essential to achieving zero leprosy.
Measuring progress towards reaching the targets of Global Leprosy Strategy 2021-2030
| Indicator | 2019* (Reported) | 2023 (Milestone) | 2025 (Milestone) | 2030(Milestone) |
| Number of countries with zero new autochthonous cases | 34 | 75 (39%) | 95 (49%) | 120 (62%) |
| Number of new cases detected (disaggregated by sex and age) | 202,256 | 148,000 | 123,500 | 62,500 |
| Rate (per < 1/million population) of new cases with G2D | 1.4 | 0.92 | 0.68 | 0.12 |
| Rate (per million children) of new autochthonous child cases with leprosy | 7.83 | 5.66 | 4.24 | 0.77 |
*Annual leprosy Data of 2019 are considered as baseline for monitoring progress towards reaching of targets of NTD Roadmap 2030 and Global Leprosy Strategy 2021-2030.
In 2020, WHO brought out a Leprosy/Hansen Disease management of reactions/prevention of disabilities; a published the technical guide – 2020 to provide hands-on guidance to health workers to diagnose early and manage
Lepra reactions, conditions might occur as a result of the host’s immune response to the infecting organism,
M leprae. These intermittent and recurring inflammatory episodes are known as leprosy reactions. These reactions might occur in as many as 50% of cases. Reactions if left unmanaged in most cases lead to permanent, progressing and disfiguring disabilities.
The objective of this Technical Guidance document is to review current management practices for leprosy reactions and neuritis and to describe ways in which they can be improved, so that national programmes can achieve their goals of preventing and minimizing disability due to leprosy.
WHO in 2020, brought out a technical guide on: Leprosy Hansen disease contact tracing and post-exposure prophylaxis - 2020. The objective of the technical guide is to advise countries and programmes on how to implement contact screening and chemoprophylaxis with single-dose rifampicin. The contents are logically ordered: counselling and obtaining consent, identification and listing of index case, listing of contacts, tracing of contacts, screening of contacts, administration of prophylactic drugs. Managerial aspects to undertake contact screening and chemoprophylaxis are also elaborated, including planning, training, supervision, and drug management.
The Global Leprosy Strategy 2021–2030 guides the countries to accelerate progress towards zero leprosy, in line with the Sustainable Development Goals. Optimization of existing tools, such as for contact-tracing, active case-finding, post-exposure prophylaxis with single-dose rifampicin and provision of MDT services are critical activities to interrupt the transmission. The gains must be sustained to ensure elimination by 2030.
Although the COVID-19 pandemic disrupted health services in general, it provided a window to strengthen digital health initiatives for diagnosis, referral, monitoring and training staff in several countries.
WHO has developed e-learning modules that aim to enhance knowledge and skills of staff at all levels on topics ranging from suspected referrals and diagnosis to the treatment of leprosy and management of disabilities.