Leprosy  -  The Facts


Leprosy: A 2-minute Clinical Summary


Leprosy presents in patients with one (or more) of 3 main clinical manifestations -

  • one cosmetic that can be resolved
  • the other two causing horrible mutilating often progressive deformities.


1.   Cosmetic:  skin patches - curable, resolvable and normally disappear with multi drug therapy (MDT)


2.   Mutilating:  irreversible nerve damage that leads to:

  • blindness - loss blinking (lagophthalmos) and loss of sensation of cornea. Blindness.
  • loss of sensation and function of hands - leading to deformed claw hands, wrist drop and eventual loss of fingers
  • loss of sensation and function of feet - leading to foot-drop, repeated ulcers, infection, osteomyelitis of the feet, and eventual loss of toes and then feet  


3.   Mutilating:  Leprosy Reactions - Type1 and Type 2 - an unpredictable immunological response - affect about 40% of all leprosy patient

  • Type1 Leprosy Reaction - leading to activated skin patches and accelerated nerve damage 
  • Type 2 Leprosy Reaction - a whole-body immune reaction, resulting in fever, unwellness, and affecting the skin with multiple painful nodules that erupt onto the skin like boils, plus other multi-organ effects - can result in death


THE MESSAGE?  Detect, diagnose and treat leprosy EARLY, before any irreversible nerve damage occurs




More details about leprosy  - see below the pictures - its causes, magnitude, treatment, complications etc 





Leprosy blindness and loss of fingers
Although he completed his multi-drug therapy (MDT) 15 years ago and is no longer infectious, he is still slowly progressively going blind and losing his fingers because of nerve damage and lost sensation and function of eyelids (lagophthalmos) and hands

1.   Skin Patches - mostly of cosmetic significance - usually disappear with MDT treatment

2.   Nerve Damage  -  mostly irreversible - leads to blindness, mutilating destruction of fingers, hands, feet - often progressive even years after MDT is finished

3.  Type 1 and Type 2 Leprosy Reactions*   -   occur unpredictably and repeatedly and can occur for 25 years or more after MDT treatment is finished


Type 1 Reactions can exacerbate nerve damage;    

Type 2 Reactions can be fatal.


* Type 1 are also known as "Reversal Reactions";  

* Type 2 are also known as "ENL" or "Erythema Nodosum Leprosum" Reactions




Briefing on Leprosy  -  adapted from WHO Leprosy Fact Sheet (Oct 2016) , and other WHO Leprosy information


Key facts 

  • Leprosy is a chronic infectious disease caused by a slowly multiplying bacillus, Mycobacterium leprae, the same bacterial family as tuberculosis (Mycobacterium tuberculi)
  • The average incubation period of the disease is about 5 years. However symptoms can appear within weeks of infection or may take as long as 20 years to appear. The incubation period seems much shorter in the Nepal Terai region, as evidenced by young children of 5 and 6 suffering from leprosy
  • The disease mainly affects
    • the skin and mucosa of the upper respiratory tract,
    • the peripheral nerves, especially innervation of the eyes, hands and feet,
    • the immune system resulting in Leprosy Reactions - Type 1 and Type 2.
  • Leprosy is curable.
  • Leprosy is most likely transmitted via droplets from the nose and mouth, and perhaps by other means of contact, during close and frequent contacts with untreated cases. Even for this ancient disease, this mode of transmission is not fully confirmed.
  • Early diagnosis and treatment with multidrug therapy (MDT) remain key in curing and eliminating the disease as a public health concern.
  • Official government figures from 136 countries show the global registered prevalence of leprosy at 174,608 at the end of 2015 and during the same year, 210,758 new cases were reported. The actual number, as shown by recent large surveys in northern India, is likely to be very much higher.
  • Untreated, leprosy can cause progressive and permanent damage to the skin, nerves, eyes and limbs, resulting in disfiguration, blindness, loss of fingers, hands, and feet.
  • It is estimated that there are between one and two million people are currently visibly and irreversibly disabled due to past and present leprosy, and who require to be cared for by the community in which they live.


Background on Leprosy


Leprosy has afflicted humanity since time immemorial. It once affected every continent and it has left behind a terrifying image in history and human memory - of mutilation, stigma, marginalization, rejection and exclusion from society.


Leprosy has struck fear into human beings for thousands of years, and was well recognized in the oldest civilizations of China, Egypt and India. It is frequently mentioned in the Bible - Old and New Testament. A cumulative total of the many many millions of individuals who, over the millennia, have suffered its chronic course of incurable disfigurement and physical disabilities can never be calculated.


Since ancient times, leprosy has been regarded by the community as a contagious, mutilating and incurable disease. There are still many countries in Asia, Africa and Latin America with a significant number of leprosy cases. It is estimated that there are between one and two million people are currently visibly and irreversibly disabled due to past and present leprosy, and who require to be cared for by the community in which they live.


Dr G.A. Hansen first discovered the bacteria M.leprae in 1873 at his hospital (now a museum) in Bergen, Norway - in those days leprosy was still prevalent in Europe. It was the first bacterium to be identified as causing disease in man.


Current Magnitude of Global and India-Nepal Leprosy Situation - (see latest WHO Global Leprosy Update for 2015:  www.WHO Global Leprosy Update-Sept2016)


Leprosy data are reported currently from 136 countries worldwide. However most of these countries have reached "elimination" status at national level (defined as a prevalence of <1 per 10,000 population), and now only 14 countries report more than 1000 new cases per year. The South-East Asia Region accounts for 74% of new cases worldwide - the major burden being from India, Bangladesh, Indonesia, and Nepal. India and Nepal account for 62% of the world's leprosy.


Even though many countries have achieved "elimination" at national level, pockets and populations with high endemicity still remain in some foci, regions, districts, as in Angola, Brazil, the Central African Republic, India, Madagascar, Nepal and the United Republic of Tanzania, Democratic Republic of the Congo and Mozambique.


The very high new case detection rates and leprosy-patient numbers seen in the hot flat densely populated contiguous region of north India and southern Nepal, suggest that this region is outstandingly the world' greatest epidemiological hot-spot for leprosy.




The first breakthrough in treatment for leprosy only appeared in the late 1940s with the introduction of dapsone, which arrested the disease. But the duration of the treatment was usually for life, making it difficult for patients to follow. Furthermore in the 1960s, M. leprae started to develop resistance to dapsone, the world’s only known anti-leprosy drug at that time.


In 1981, a WHO Study Group recommended MDT (multidrug therapy). It consists of 3 drugs: dapsone, rifampicin and clofazimine and this drug combination kills the pathogen and cures the patient.


Since 1995, WHO provides free MDT for all patients in the world, initially through the drug fund provided by the Nippon Foundation and since 2000, and through the MDT donation provided by Novartis and the Novartis Foundation for Sustainable Development.


MDT is crucial for helping slowly reduce and eliminate leprosy worldwide, and WHO and governments focus on leprosy diagnosis, MDT distribution, and progress towards "elimination". However the enormous problem of millions of people affected by leprosy (PALs) of all ages, children, adults, elderly, who are visibly and permanently disabled and deformed, is scarcely addressed by WHO or government programmes.  LLSC's programmes attempt to address both the elimination of leprosy through early diagnosis and treatment with MDT, and also the enormous problem of leprosy-caused disability - especially blindness, hand and feet deformities.   


WHO Global Leprosy Strategy 2016-2020: "Accelerating towards a leprosy-free world"


The WHO Strategy is built around three major pillars:

  • strengthen government ownership and partnerships;
  • stop leprosy and its complications; and
  • stop discrimination and promote inclusion.

Its goal is to further reduce the global and local leprosy burden, thereby aiming for…

  • zero children with leprosy-affected disabilities,
  • a reduction of new patients diagnosed with leprosy-related deformities to less than one per million population, and
  • a repeal of all laws that allow discrimination of leprosy patients.

The WHO Strategy for leprosy elimination contains the following:

  • ensuring accessible and uninterrupted MDT services available to all patients through flexible and patient-friendly drug delivery systems;
  • ensuring the sustainability of MDT services by integrating leprosy services into the general health services and building the ability of general health workers to treat leprosy;
  • encouraging self-reporting and early treatment by promoting community awareness and changing the image of leprosy;
  • monitoring the performance of MDT services, the quality of patients’ care and the progress being made towards elimination through national disease surveillance systems.

Sustained and committed efforts by the national programmes along with the continued support from national and international partners have led to a decline in the global burden of leprosy. Increased empowerment of people affected by the disease, together with their greater involvement in services and community, will bring us closer to a world without leprosy.


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