Leprosy in film context

Some friends and I started an independent and foreign film club where we get together once a month and watch a "little-known" movie that may have been overlooked and discuss them. This month, the host chose "The Motorcycle Diaries", a film that depicts the early life of Che Guevara and is based on his own written accounts. The movie shows how a simple motorcycle trip he took with a friend when he was 23-years old shaped his life and ideals and made him into the Marxist revolutionary he ultimately became. The catalyst for this change from his predetermined path of solely being a doctor was witnessing the unequality of the class system and poverty across Latin America but more profoundly, through his work at a leper colony in San Pablo where he was confronted with the segregation of the sick and the healthy. After watching the film when we were discussing it, someone asked about the causation of leprosy and exactly what it is. There was also a moment in the film where it was mentioned that leprosy can not be spread after a person undergoes treatment, which none of us had ever heard before. We did not know exactly what this treatment was nor did the script of the film give us any answers. I then became interested in learning more about this disfiguring disorder and any known therapy.

I first remember hearing about the condition of leprosy from sunday school, where we read passages of the bible. Going back to biblical times, leprosy was described as a horrific disease where limbs commonly fall, discoloration of the skin can spread to clothing, and hair turns white. Though this has been translated as lepra or leprosy, this is apparently more common to the disease tzaraath. Leprosy, a disease caused by the bacterium Mycobacterium leprae, initially surfaces as dark or light spots on the skin and loss of feeling in the toe or finger. As time passes, more serious effects of the disease are apparent due to the bacteria attacking the peripheral nervous system. The infected person experiences numbness through limbs. This is particularly dangerous because the person could severely injure themselves and have infections in these areas and not know it. Repeated injury could then result in lost of limbs. Mycobacterium leprae is also known to attack the nerves around the eyes, affecting the blinking reflex which is important to ward of debris and moisten the eye. Due to this lack of protective mechanism by the eye, blindness may result. Damage to the internal lining of the nose is also common. This bacteria favors temperatures slightly below that of normal human body temperatures, which contributes to why infection of superficial body tissues (i.e. skin, nose) is common. Additionally, Mycobacterium leprae almost exclusively infects humans, making studying this disease difficult because of lack of good animal models.

Against popular belief, leprosy is not very contagious. In biblical texts, lepers were viewed as "unclean" and were shunned from society. This is also consistent with the modern-day treatment of lepers who are expelled from their communities and forced into quarantine in leper colonies. However, modern medicine has shown this to be totally unnecessary. Leprosy is thought to spread through the coughs and sneezes of an infected person though prolonged contact is required. Also, 95% of people have a natural immunity to this bacterial infection. Additionally, treated persons with leprosy are no longer contagious and can not pass the disease on.

Two major forms of leprosy exists - tuberculoid and lepromatous. The organism that causes leprosy has a relatively long incubation time which is different between tuberculoid and lepromatous leprosy. This is possibly due to Mycobacterium leprae having a slow dividing time (approximately once every 12 days), unlike other bacteria. About four years is needed before symptoms of tuberculoid becomes obvious while an upwards of eight years for the more severe lepromatous leprosy is needed. Both forms produces skin discoloration and spots, though the lepromatous form causes disfiguring nodules. A person will commonly develop tuberculoid leprosy but if it is not treated promptly or an immune response to the organism is not sufficient, lepromatous leprosy can develop. Leprosy is traditionally diagnosed using a skin scraping exam which including skin biospy. In order to distinguish between the two types, a lepromatous skin test is often given to patient inflicted with leprosy.

In terms of treatment, in the late 1930s, dapsone was introduced as a treatment strategy for leprosy. Dapsone is a antibacterial drug that inhibits bacterial synthesis of dihydrofolic acid, preventing nucleic acid synthesis. This drug ultimately failed as a single agent due to acquired drug resistance. However, the introduction of a multidrug treatment (MDT) for leprosy makes leprosy curable. In addition to dapsone, patients are also given the rifampin, a semi-synthetic compound which binds to the bacterial DNA-dependent RNA polymerase beta subunit and inhibits its activity, and clofazimine, an anti-inflammatory agents which controls redness common to leprosy. Treatment typically lasts six months to two years and has proven successful.

The World Health Organization (WHO) estimates that there are still 200,000+ cases of leprosy still remain. Though most countries have eliminated this disease among their populations, small numbers of countries have pockets of leprosy (i.e. areas in South American and India). As of 1995, WHO makes available free MDT treatment worldwide.

Recent news:
WHO/Novartis sign MoU to extend the MDT donation
Leprosy cases in Brazil drops by 24.27% in last two years

References:
About.com: Leprosy (Hansen's disease)
MedlinePlus: Leprosy
Merck: Leprosy
World Health Organization: Leprosy Today