Wednesday 14 June 2017

The story of leprosy: from 2000 BCE to now

Throughout human history, very few diseases have carried the levels of stigma and shame that leprosy brings upon it’s sufferers. One of the oldest known illnesses, Mycobacterium leprae is thought to have been with mankind in one form or another for well over four millennia and traveled along the migration routes through East Africa and the Near East.
Leprosy takes its name from the Latin word  lepra, meaning “scaly”, as the predominant symptom of infection are raised skin lesions. However in modern medical circles it is more commonly referred to as Hansen’s disease, after G. H. Armauer Hansen, the Norwegian physician who identified Mycobacterium leprae as the causative agent.

Girls in the Philippines identified as having leprosy. Image: National Museum of Health and Medicine
Contrary to popular belief, leprosy does not cause body parts to fall off. Infection with M. leprae instead leads to severe nerve damage in the skin, limbs and eyes. This can leave suffers vulnerable to secondary infection if they do not receive adequate medical attention, and gangrene may then set in.
Neither is leprosy particularly infectious. In fact, 95% of the world’s population has a natural immunity to M leprae (although they may still be able to carry it). Even then, it takes prolonged exposure to a sufferer for infection to pass. The idea that just brushing past a leper would make you somehow “unclean” is yet another myth.
In 2009, a mummified skeleton from circa 2000 BCE was found in northwest India. DNA analysis of the remains found evidence of  M. leprae infection within the skeleton, the oldest yet known case of leprosy. An Egyptian Papyrus document written around 1550 BCE makes mention of a disease that may be leprosy and Hippocrates discusses the infection in his writings in 460 BCE. In China, the Feng zhen shi manuscriptwritten about 250 BCE discusses a condition that leads to destruction of the nasal septum as well as anaesthesia, which is also very likely leprosy.
The Bible makes multiple reference to “tzaraath”, a disfiguring disease which most translations render as leprosy, DNA found on in a tomb in the Old City of Jerusalem, dated 1-50 AD confirmed the presence of the disease in the area at the time. In Ancient Rome both Pliny the Elder and Aulus Cornelius Celsus wrote about the presence of lepers in and around Rome and the Near East.
Historical accounts of leprosy can be hard to identify as some may mistake psoriasis, vitiligo or other skin conditions for leprosy. The descriptions of highly infection skin conditions are more likely fungal infections than leprosy, and, after 1492 when Columbus returned from the new world after exchanging small pox for syphilis, that gets added to the mix too.
In many writings from the mid-16th century onwards, descriptions of “leprosy” begin to more resemble congenital or tertiary stage syphilis – patients with collapsed noses and rotting ears, loss of skin on the palms of the hands and feet, deafness and loss of teeth. This may also explain the sudden increase in numbers of “leprosy” suffers seen in the 16th century.
Leprosy has long been associated with a curse, or believed to be a punishment from God for sins committed in this life or a previous one. This link has been made throughout many cultures and continents. Because of this, suffers throughout history were often denied treatment and care. Instead they were sunned by society and quarantined in purpose-built asylums or leper colonies.
Unlike many infectious diseases, leprosy does not have a long history of ridiculous cures and treatment. This is probably because of the association it has had with being unclean or cursed in some way. Doctors or priests would refuse to treat the afflicted as they would not want to be associated with the illness. There was also the general thought that you have “brought the disease upon yourself” in some way.
The Ancient Egyptians, writing circa 1550 CBE recommend bathing in blood to alleviate the symptoms of leprosy and it seems that this was the go-to treatment across Europe, the Middle East and into China for millennia. There is some variation in the source of the blood that is recommended, from child to dog to lamb, and whether or not it should be also used as a beverage, but the theme remains.
Pliney the Elder makes mention of snakes blood, but also mentions that he doesn’t think it will help. However Philippe Gaucher, a 19th century French doctor stepped it up to applying cobra venom to the skin lesions, and as late as 1913 a Dr Boinet tried increasing doses of bee stings (up to 4000, apparently) to no avail. Bare in mind, the bacteria causing the infection had been identified in 1873.
As of 2016, worldwide, two to three million people were estimated to be permanently disabled because of Hansen’s disease. Although the disease is now entirely treatable with multidrug antibiotic therapy, the stigma that is associated with leprosy infection still prevents some sufferers from seeking or receiving treatment.
The disease is traditionally associated with poverty and sadly that link still remains. The necessary multidrug treatment is comparatively expensive, however Novartis, the company that produces it, offers it for free.  Several leprosy charities exist, with the goal to treat those infected. Some also offer reconstructive surgery and artificial limbs, which can help sufferers reintegrate into society.

The inhabitants of the Kalaupapa leper colony in 1905. Image: Wikipedia
There are many leper colonies left in the world, over 800 in India alone and in Europe, one leper colony still remains. Tichileşti is in Romania and had 19 inhabitants in 2011. Although the people living there have been given the necessary treatment most are now very elderly and feel they are unable to leave.
Approximately 150 people are diagnosed with leprosy each year in the U.S.A, although due to the long dormancy period of the bacteria (from two years to over a decade) it is hard to identify where they contracted the initial  infection. There have been two cases reported in the last three years in the UK, both in men who recently moved from the Indian subcontinent.
M. leprae has a natural reservoir in armadillo populations and in red squirrels, although there have been no known cases of animal to human transmission from squirrels, there is some evidence that it may be possible to catch leprosy from an armadillo. If you were both unlucky enough to be genetically vulnerable to M. leprae and had prolonged exposure to said infected armadillo.
Cases of Hansen’s disease worldwide have dropped rapidly over the last 30 years, from 5.2 million in 1985 to about 210,000 a year now. In 2000 the WHO declared it was no longer a public health problem. Both the WHO and Novartis believe that, through new screening techniques that especially target at-risk children, by 2020 child suffers will no longer develop deformities. There is the potential to fully wipe out leprosy, as we did with smallpox, early detection of infection being key.

Published Nouse 13/06/2017