In the summer of 2000, robbers ransacked an ancientfamily burial cave at Akeldama in the Hinnom Valley in Jerusalem. Thieves had been there before, smashing open the stone caskets that held the bones of the dead. This time the looters found a lower burial chamber, and in the depths discovered a secret sepulchre, a niche in the rock that had been blocked with a boulder and sealed with cement. By the time archaeologist Shimon Gibson arrived a few hours later, the thieves had done their worst and fled. But they had left something. Inside the sepulchre lay a tangled mess of brown fibres. To thieves, it looked worthless. To Gibson, it looked priceless. These were the remains of a man still wrapped in his burial shroud. When this man died, itwascustomaryto lay the dead in a niche and return laterto rebury the bones in a stone chest. Why had no one come backforthis man鈥檚 bones? When archaeologists discovered the answer, they also found the key to a much greater puzzle.
WHEN tomb robbers found an intact sepulchre in a tomb at Akeldama, they immediately set to work to free the stone that blocked the entrance. The stone had been sealed in place with strong cement-like mortar and it took considerable effort to hack it out. With the stone gone, one thief knelt down to look inside. 鈥淵ou could see the imprint of his knees in the soil,鈥� says Shimon Gibson, a member of the archaeological rescue team that rushed to the scene. The grave was little more than a narrow tunnel in the rock, and even with a torch it was hard to make out what the unprepossessing brown heap inside might be. 鈥淭hey were after caskets or jewels 鈥� something valuable. When they saw the brown mess, they left it.鈥�
Closer inspection revealed that the brown material was a mixture of hair and the remnants of a wool-and-linen burial shroud. There were fragments of bone too. The discovery of the shrouded man offered a rare opportunity to carry out a thorough investigation of a Jewish burial from biblical times. Carbon dating of the shroud put the man鈥檚 death somewhere in the first half of the 1st century AD. And the man clearly came from a family of note. 鈥淭he tomb was at the foot of Mount Zion, a stone鈥檚 throw from the city and in a priestly and aristocratic quarter,鈥� says Gibson. A neighbouring tomb belonged to the family of Caiphus, the high priest who delivered Jesus into the hands of Pontius Pilate.
Advertisement
Such a man might expect to receive the customary burial rites: but instead of leaving his body in a niche for a year or so and then reburying his bones in an ossuary, his family had walled him up in the rock. They must have had a reason. Palaeopathologist Mark Spigelman, who splits his time between the Hebrew University of Jerusalem and University College London (UCL), suspected the man鈥檚 relatives were afraid to collect his bones.
鈥淓very other skeleton was in an ossuary,鈥� says Spigelman. 鈥淭his was a high-class, deeply religious family. There has to be a reason why they didn鈥檛 observe the normal rituals. Either there was some sort of social upheaval that prevented it, in which case we would never know, or they were too scared to do it.鈥� The fact that someone sealed the niche so carefully suggests they never intended to open it again. 鈥淭hat made me think they were afraid of something,鈥� says Spigelman. 鈥淎nd that made me think maybe he was a leper.鈥�
Spigelman and his colleague Helen Donoghue, an expert on ancient DNA at UCL, decided to test his hunch. As part of the team investigating the tomb, they had been asked to look for DNA from Mycobacterium tuberculosis, the bacterium that causes TB. Some bones from the tomb showed the hallmarks of infection, but only the presence of bacterial DNA would confirm the diagnosis. They found plenty. The shrouded man was so heavily infected he probably died from the disease. But samples of his bone produced DNA from a second mycobacterium, M. leprae. Just as Spigelman suspected, the man had leprosy.
鈥淧eople with leprosy were cast out from society. They lost family, property and livelihoods and relied on charity for survival鈥�
In China and India leprosy is an ancient disease, but there is a big question mark over when it reached the Middle East. The 鈥渓epers鈥� of the Bible鈥檚 Old Testament were not suffering from leprosy, says Gibson. The word referred to people with skin diseases in general and to those regarded as spiritually unclean. But did this apply to the lepers of the New Testament? 鈥淣ow that we have a confirmed case from Jerusalem in the 1st century, it鈥檚 more likely that the lepers of the New Testament did genuinely have the disease,鈥� says Gibson.
For Donoghue and Spigelman the discovery was significant for a different reason. They were intrigued by the fact that the shrouded man had widespread and active infections of both TB and leprosy. For almost a century, historians and archaeologists have accepted the theory that infection by M. tuberculosis makes the body immune to M. leprae, a notion that neatly explained why leprosy suddenly began to disappear from western Europe in the late Middle Ages. As TB spread, encouraged by migration from the land into towns, leprosy began to retreat. TB kills only a fraction of those it infects, and around 90 per cent show no signs of disease. So as TB became endemic it created a huge pool of people immune to leprosy.
If leprosy was a recent arrival in the Middle East, it came even later to western Europe, carried north and west by the Romans. Later still, the Vikings took it home to Scandinavia, while the Crusaders probably spread it about still more. By the 12th century the disease had reached a peak. Leprosy is hard to transmit and rarely fatal, yet it was feared like no other disease. Those diagnosed with it were immediately cast out from society and subject to harsh laws. They lost family, property and livelihoods, and relied on charity for survival. But by the 13th century the disease was in sharp decline, and by the 16th century it was virtually gone. In its place was the new scourge of tuberculosis.
The discovery that the man from Akeldama had both TB and leprosy prompted Donoghue and Spigelman to re-examine samples from other ancient sites that they and their colleagues had worked on. They found DNA from both bacteria in bones from Dakhleh Oasis, a 4th-century Egyptian shrine visited by people with leprosy, at P眉sp枚klad脿ny, a 10th-century burial ground in Hungary, and at a Viking-age cemetery in northern Sweden. 鈥淲e realised we were looking at a fairly common, previously unrecognised phenomenon of co-infection,鈥� says Donoghue. 鈥淭hese diseases clearly coexisted in the past.鈥� The idea of cross-immunity was beginning to look a bit shaky.
The theory arose because M. tuberculosis and M. leprae have some identical antigens, which trigger production of identical antibodies. Even a symptomless TB infection would leave the body equipped with antibodies against invading M. leprae. But as Donoghue points out, antibodies are not the body鈥檚 main line of defence against mycobacteria. These pathogens operate from inside their host鈥檚 cells, and it takes bigger guns 鈥� the killer cells and macrophages of the cell-mediated immune response 鈥� to defeat them.
Donoghue and Spigelman think leprosy declined not because TB protected against it, but the opposite: leprosy made people extremely vulnerable to TB. Their defences were already down, making them easy prey for the big killer. People who develop the most disfiguring form of leprosy are known to have a defect in their cell-mediated immune response. But even without such a breach in their defences, people who had leprosy in the Middle Ages would have had few resources to fight a second infection. 鈥淭hese people suffered terrible social stigma,鈥� says Donoghue. 鈥淭hey were isolated and moved on. They relied on alms and probably never had enough to eat. And they would have been depressed. All these things would have had a profound effect on their immune response. They would be very susceptible to TB.鈥� Anyone with a latent TB infection who went on to contract leprosy would not live long either. 鈥淚f they got leprosy, the stress and stigma would lead to immunosuppression and the TB would emerge and kill them.鈥� TB, then, made short work of Europe鈥檚 outcasts until there were too few to maintain the disease.
The man in the shroud was no outcast. His family abandoned him only after he was dead. 鈥淗e didn鈥檛 have to beg for alms or scrape a living among the rubbish dumps and sewers of Jerusalem,鈥� says Gibson. 鈥淲e found his hair was clean and well kept. He was cared for and looked after.鈥� But even so, leprosy eventually wore down his immune system and made him prey to TB.
