Leprosy

Leprosy is a chronic infectious disease caused by the bacterium Mycobacterium leprae.

It is mainly a granulomatous disease (lesions of epithelioid macrophages) affecting: peripheral nerves and mucosa of the upper-respiratory tract

Brief History

• Gerhard Henrik Armauer Hansen was the physician which first identified Mycobacterium leprae as the cause of leprosy in 1873.

Mycobacterium leprae

• M. Leprae is an acid fast, rod shaped bacillus. It mainly affects the skin, peripheral nerves, and mucosa of the respiratory tract etc.
• Transmission: prolonged close contact, Inhalational
• Incubation period: 2 to 5 years or more

According to official reports received from 115 countries and territories, the global registered prevalence of leprosy at the end of first quarter of 2013 was 189,018 cases, while the number of new cases detected during 2012 was 232,857

Leprosy has left behind a terrifying image in history and human memory of mutilation, rejection and exclusion from society.

Based on morphology

• Paucibacillary
• Multibacilary

Based on immunology

• Tuberculoid
• Lepromatous

• Hypopigmented anesthetic patches
• Thickened nerve
• Loss of eye lashes
• Weakness of hand and feet
• Ulcers
• Auto amputation

Acid-fast bacilli on skin smears or biopsy

The elimination of leprosy as a public health problem means reducing the prevalence of leprosy to below one case per 10,000 population.

Elimination of leprosy can be achieved by:

• Making MDT (Multi-Drug Therapy) accessible to all communities and areas.
• Treating all registered cases with MDT
• Diagnosing and promptly treating all new cases
• Improving quality of patient care, including disability prevention and management
• Ensuring regularity and completion of treatment
• Enlisting community support for the program

A. Chemotherapy

First line drugs are Rifampicin, Dapsone, and Clofazimine

The WHO recommends that if a patient test positive in an acid-fast skin smear they should be treated for multibacillary disease

The patient’s bacterial load decides length of treatment (6-24 months)

Second line drugs are Ofloxacin and Minocycline

B. New Nerve Damage

Patients with motor or sensory loss of 6 months or less should receive a 6 month treatment of corticosteroids

C. Preventing Disability

Nerve damage produces anaesthesia, dryness and muscle weakness which in turn causes misuse of affected limbs causing ulceration and infection, leading to deformity

Dryness can lead to skin cracking and ultimately infection

Treatment involves soaking and applying oil- based creams to affected areas, also physiotherapy can help prevent contractures, muscle atrophy and over stretching of muscles

• Highly effective in curing the disease
• Reduces the period of treatment
• Well accepted by patients
• Easy to apply in the field
• Prevents the development of drug resistance
• Interrupts transmission of infection
• Reduces risk of relapse
• Prevents disabilities
• Improves community attitude

Over the past 20 years, more than 14 million leprosy patients have been cured, about 4 million since 2000.

The prevalence rate of the disease has dropped by 90% – from 21.1 per 10 000 inhabitants to less than 1 per 10 000 inhabitants in 2000.

Dramatic decrease in the global disease burden: from 5.2 million in 1985 to 805,000 in 1995 to 753,000 at the end of 1999 to 189,018 cases at the end of 2012.

Leprosy has been eliminated from 119 countries out of 122 countries where the disease was considered as a public health problem in 1985.

So far, there has been no resistance to anti leprosy treatment when used as MDT.

Efforts currently focus on eliminating leprosy at a national level in the remaining endemic countries and at a sub-national level from the others.

LEPROSY is a treatable disease and prompt diagnosis and treatment is necessary.

1. Discuss leprosy control using the levels of disease prevention
2. Provide information on the various leprosy control program