Leprosy (or Hansen’s disease) is a chronic infectious disease caused by the Mycobacterium leprae, which affects the peripheral nerves, the skin and the mucosa, and results in severe disabilities. Leprosy is a contagious disease. The leprosy bacillus is transmitted via droplets from the mouth or nose, during contacts with an infected untreated subject. The incubation period of the disease is about 5 years but symptoms can take as long as 20 years to appear, which makes it difficult to identify those affected.
Leprosy becomes an incapacitating disease when neurological damages appear in the eyes, hands or feet. At its initial stage, most often a painless spot on the skin, the disease does not cause any particular problem, which means that people usually dismiss the lesions as banal and delay seeking a consultation. Yet, it is at this stage that antibiotic treatment is most efficient and may avert the onset of complications, hence the importance of raising as much awareness as possible about the early signs of the disease.
Several factors are associated with the disease, such as poverty, lack of hygiene and malnutrition. A person in good health with an efficient immune system will eliminate the bacillus from their body. Therefore, there is a strong link between the disease and a country’s level of development.
Leprosy affects about 200,000 new cases a year across the world and is developing in Southeast Asia, Africa and South America. Left untreated, leprosy may lead to progressive permanent damage to the skin, peripheral nerves, limbs and eyes. It may also cause a complete loss of sensation in the feet and/or hands.
Treatment for the disease is distributed free of charge by the World Health Organization (WHO) and combines three antibiotics (multi-drug therapy or tri-therapy). The treatment duration varies from 6 to 12 months depending on the type of leprosy (paucibacillary or multibacillary). Unfortunately, in too many cases, those affected are diagnosed only very late, after they have already suffered the incapacitating effects of the disease. Although in some cases, they may partially regain some abilities, thanks to reconstructive surgery, these people remain marked for life and are often rejected by their families and society. The treatment may also cause adverse side effects. Patients must be monitored during their treatment.
Primary prevention of leprosy as such does not exist since the way in which the disease is transmitted and acquired is still not very well known, due to its very long incubation. It of course requires the rapid detection of new cases and their timely access to treatment in order to eliminate the excretion – mainly nasal – of the bacillus of multibacillary patients. Prevention therefore calls for maximum dissemination of knowledge about the disease in the population and among various health professionals, as well as the active rapid detection of new cases. Therefore, prevention largely depends on raising people’s awareness, as previously indicated, training healthcare workers, and active early detection.