The World Health Organization (WHO) will publish its first guidelines on leprosy as part of renewed efforts to eliminate the disease and after almost two years since the Global Leprosy Strategy 2016–2020 was launched.
Despite being eliminated as a public health problem1 globally in 2000 and at national level in most countries in 2005, cases of leprosy as reported by 145 countries from all six WHO regions continue to occur; more than 200 000 new cases were reported in 2016 alone.
“The primary audience of the guidelines includes people involved in the formulation of national policies and clinicians who are involved in the management of the disease particularly in low- and middle-income countries” said Dr Erwin Cooreman, Team Leader of the Global Leprosy Programme which is housed in WHO’s South-East Asia Regional Office in New Delhi, India. “With ongoing transmission of infection, including among children, it is clear that we need renewed efforts to eliminate the disease.”
This is the first time that WHO has developed guidelines for leprosy through evidence-based recommendations utilizing guideline development methods based on the GRADE (Grading of Recommendations Assessment, Development and Evaluation2 ) approach. Previous leprosy guidance documents were developed through meeting reports and other technical documents.
“Published literature from 2010 onwards on diagnostics, treatment regimens and on prophylaxis were retrieved and reviewed and recommendations were based on evidence” said Dr Laura Gillini, Medical Officer, Global Leprosy Programme. “However, evidence on benefits and harms of treatment for drug-resistant leprosy was not available; therefore the recommendation for treating leprosy cases with drug-resistant strains in the guidelines is based on expert opinion.”
The guidelines were developed with funding from the Nippon Foundation. Key research gaps are identified to help inform future research on leprosy.
Highlights of recommendations
Diagnosis
The guidelines maintain the standard methods for diagnosis, which include the presence of at least one of the three clinical signs of leprosy: (i) definite loss of sensation in a pale (hypopigmented) or reddish skin patch; (ii) a thickened or enlarged peripheral nerve with loss of sensation; and (iii) the presence of acid-fast bacilli in a slit-skin smear. Because the clinical diagnosis of early leprosy and paucibacillary leprosy can be a challenge, a number of serological and other laboratory assays have been developed to supplement clinical diagnostic methods.
Treatment
The use of the 3-drug regimen comprising rifampicin, dapsone and clofazimine is recommended for all leprosy patients, with duration of treatment lasting 6 months for paucibacillary leprosy and 12 months for multibacillary leprosy. The potential advantage of using the same three drugs for both forms of the disease is simplification of treatment. For patients who are resistant to rifampicin, two of the following drugs are recommended: clarithromycin, minocycline or a quinolone (ofloxacin, levofloxacin or moxifloxacin), plus clofazimine daily for 6 months, followed by clofazimine plus one of the second-line drugs daily for an additional 18 months. For patients resistant to rifampicin and ofloxacin, clarithromycin, minocycline and clofazimine may be used for 6 months, followed by clarithromycin or minocycline plus clofazimine for an additional 18 months. For adults and children (aged above 2 years) who are in regular contact with leprosy patients, the guidelines recommend the use of single-dose rifampicin.
Prevention
The ability of programmes to adequately identify and manage contacts of leprosy cases is a prerequisite for the successful implementation of the recommendations. Because leprosy is highly stigmatized, caution must be exercised when implementing single-dose rifampicin, particularly for contacts outside the patient’s family. Programmes must respect the wish of patients to disclose or not disclose their diagnosis.
The disease
Leprosy is caused by infection with the bacillus Mycobacterium leprae, which multiplies very slowly in the human body. The bacterium has a long incubation period (on average five years or longer). The disease affects nerve endings and destroys the body’s ability to feel pain and injury.
Leprosy is curable. Treatment provided in the early stages of infection averts disability. Multidrug therapy is available free of charge through WHO and has been donated to all patients worldwide by Novartis since 2000 (and by The Nippon Foundation since 1995). It provides a simple yet highly effective cure for all types of leprosy.
Continued discrimination has deterred people from coming forward for diagnosis and treatment and encouraged cases to remain hidden, indirectly contributing to transmission.
Social stigma also facilitates transmission among vulnerable groups, including migrant populations, displaced communities, and the very poor and hard-to-reach populations. Combating stigma and ensuring early diagnosis through active early case-finding is critical to making progress.
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1Elimination of leprosy as public health problem (defined as a registered prevalence of less than 1 case per 10 000 population). However, pockets of endemicity have continued in many countries. India and Brazil report the highest number of cases annually.
2GRADE includes an assessment of quality of evidence (high, moderate, low or very low), consideration of the overall balance of benefits to harms (at individual and population levels), patient/health worker values and preferences, resource use, effects on equity, cost–effectiveness and consideration of feasibility and effectiveness across a variety of settings, including resource-limited settings and those where access to laboratory infrastructure and specialized tests is limited.