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2,500-year-old poop from Jerusalem toilets contain oldest evidence of dysentery parasite
A fecal analysis from two toilets dating to biblical times in Jerusalem has revealed the oldest evidence yet of the parasite that causes dysentery.
By analyzing poop from biblical-era toilets in Jerusalem, archaeologists have discovered the oldest known evidence of a tiny parasite that causes "traveler's diarrhea," a new study finds.
This microscopic parasite, the protozoan Giardia duodenalis, can cause dysentery, an intestinal infection that results in severe, bloody diarrhea and is often accompanied by stomach cramps and a fever. The new research, published May 26 in the journal Parasitology, dates the oldest evidence of this protozoan in human feces to more than 2,500 years ago.
The researchers discovered evidence of G. duodenalis under stone toilet seats previously found at two large sites that were likely elite residences dating to the seventh to sixth centuries B.C. The stone blocks had a curved surface for sitting, a large central hole for defecating, and a smaller hole that was possibly for urination, and were situated above a cesspit. Because the ancient toilets were still in their original locations, a unique opportunity arose for specialists to identify microorganisms in the old poop.
Previous research into the cesspits has revealed eggs from whipworms, roundworms, pinworms and tapeworms, suggesting that Iron Age sanitation practices were lacking. But while these eggs are robust and can preserve for thousands of years, it is much more difficult to detect the fragile cysts produced by protozoa.
To investigate, a team of researchers from the University of Cambridge, Tel Aviv University and the Israel Antiquities Authority proved that they could identify the presence of the diarrhea-causing parasite using a technique called ELISA (enzyme-linked immunosorbent assay), which can detect the antigens — substances that trigger human immune responses — made by several different organisms.
The researchers took one sample from the cesspit at the House of Ahiel, located just outside the city walls of Jerusalem, and three samples from the cesspit at Armon ha-Natziv, located about 1 mile (1.6 kilometers) south of the city. Using ELISA kits, they detected in the feces samples a unique antigen: a cyst wall protein that is produced and released by G. duodenalis.
G. duodenalis is a tiny, pear-shaped parasite spread through food or water contaminated with the feces of an infected person or animal. The organism disrupts the protective lining of the human gut, allowing it to gain access to the nutrients there. Most people who are infected with G. duodenalis recover quickly without antibiotics. However, because the parasite breaches the gut lining, bacteria and other organisms can enter as well, potentially making a person very sick.
"We cannot tell the number of people infected based on sediment samples from communal latrines," study lead author Dr. Piers Mitchell, who specializes in paleo-parasite research at the University of Cambridge, told Live Science in an email. "It is possible the toilets may have been used by family and staff, but that is merely a possibility, as no records survive describing that sort of social etiquette."
The discovery of G. duodenalis in Iron Age toilets represents "the earliest known evidence for G. duodenalis so far identified in a past population anywhere in the world," according to the study authors, suggesting the "long-term presence of this parasite in the populations of the Near East."
It is unknown exactly how long G. duodenalis has been giving humans dysentery, but medical texts from Mesopotamia, one of the earliest complex societies, refer to the problem of diarrhea around 3,000 to 4,000 years ago. Additionally, since this symptom is common in environments with overcrowding and premodern sanitation, outbreaks of dysentery may have been common in the Near East as soon as permanent settlements and animal and plant domestication occurred.
"Much more research applying ELISAs to early societies is needed for us to fully understand from which regions of the world each organism originated, and when they spread to new areas due to migrations, trade and military invasions," the researchers concluded.
注释：
biblical: adj
表示" 圣经的"，means "of or pertaining to or contained in or in accordance with the Bible"，如：A good life is not measured by any biblical span.生活的好坏并不以圣经的标准来衡量。
dysentery: n
表示" 痢疾"，means "an infection of the intestines marked by severe diarrhea"，如：He was attacked with dysentery . 他患了痢疾。
parasite: n
表示" 寄生虫；寄生生物"，means " animal (e.g. a flea, louse) or plant (e.g. mistletoe) that lives on or in another"，如：These flies carry a dangerous parasite.这些苍蝇携带一种危险的寄生虫。
protozoan: n
表示" 原生动物"，means "any of diverse minute acellular or unicellular organisms usually nonphotosynthetic"，如：People get malaria from Anopheles mosquitoes that themselves are infected with a protozoan parasite called Plasmodium. 人们从疟蚊感染了疟疾，它们被感染的原生动物寄生虫称为疟原虫。
Duodenitis：n
表示" 十二指肠炎"，如：How are duodenitis and colonitis treated? 十二指肠炎和结肠炎怎么治?
cramp: n
表示"抽筋；痉挛"，means " a painful stiffening of muscles"，如：The swimmer got cramp in his legs and had to be helped out of the water.游泳者两腿抽筋，不得不由他人救助出水。
Parasitology: n
表示" 寄生虫学"，如：He hopes to reinstate parasitology and malaria research, areas that were lost by staff departures.他希望因为员工的离开而放弃了的对寄生虫学和疟疾领域的研究能够恢复。
defecate: v
表示"排便；"，means "have a bowel movement"，如：The fleas will defecate on the person as they feed on their blood. 跳蚤还会在此人身上排便，因为它们就是以人血为食的。
cesspit: n
表示"粪坑；垃圾坑"，means "a covered cistern; waste water and sewage flow into it"，如：It’s a sorry reminder that football can be a real cesspit. 很遗憾，这再次提醒世人，足球真的是一个污水坑。
whipworm: n
表示" [动](尤指寄生在人体肠内的)鞭虫"，如：whipworm infection 鞭虫感染
roundworm: n
表示" 蛔虫"，如：Roundworm is a worldwide distribution of human parasites, the infection is widespread in China, especially in rural areas. 蛔虫是世界性分布的人体寄生虫，在我国感染很普遍，特别是在农村。
pinworm: n
表示" 蛲虫"，means "small threadlike worm infesting human intestines and rectum especially in children"，如：Pinworm eggs were not discovered all around. 流行因素调查未见蛲虫卵。
tapeworm: n
表示" 绦虫；蛔虫"，如：The tapeworm is an inhabitant of the intestine. 绦虫是栖居肠内的寄生虫。
sanitation: n
表示"卫生系统/设备；"，means " systems that protect people's health,especially those that dispose efficiently of sewage"，如：Studies show that the disease has been cut by 77 percent in some areas through providing better water and sanitation.研究表明，通过提供更好的水和卫生设备，有些地区的发病率减少了77%。
cyst：n
表示"囊肿"，means "a closed sac that develops abnormally in some body structure"，如：She had an operation to remove a cyst. 她做了囊肿切除手术。
protozoa: n
表示" 原生动物；单细胞动物"，means "in some classifications considered a superphylum or a subkingdom; comprises flagellates; ciliates; sporozoans; amoebas"，如：he numbers of viruses and protozoa in water will always decrease with time and most rapidly at warm temperatures. 水中病毒和原生动物的数量通常会随时间减少并且在暖温下减少的十分迅速。
antigen: n
表示" [医] 抗原"，means "any substance (as a toxin or enzyme) that stimulates an immune response in the body (especially the production of antibodies)"，如：It will become a tumor antigen. 它会变成一种肿瘤抗原。
breach: v; n
表示" 破坏；违背"，means " break"，如：He never do the things breach the benefits of group.他不做任何违背集体利益的事。
sediment: n
表示" 沉淀物"，means "solid material that settles to the bottom of a liquid"，如：He emptied out the water barrel to clear it of sediment. 他把水桶倒空以清掉桶底的沉淀物。
communal: adj
表示" 公有的；公社的；共有的"，means "for or by a group rather than individuals"，如：In college we had a communal kitchen. 念大学时，我们有共有的厨房。
latrine: n
表示" 公共厕所"，means "a public toilet in a military area"，如：oneybags second thinks latrine. 富翁乙想上茅房。
domestication: n
表示"驯服；教化"，means "adaptation to intimate association with human beings"，如：domestication of microorganism 微生物的驯化.
中文简要说明：
耶路撒冷有一处距今2500年前的古代石制茅坑，以色列、英国两地学者合作茅坑内古人粪便样本发现了引发痢疾的「梨形鞭毛虫」遗迹，意即铁器时代的人类已有罹患痢疾的例子。这是考古界已知最早的痢疾寄生虫证据。由于痢疾常见于旅人身上，这也反映了耶路撒冷在当时身为政治与宗教重镇人来人往的繁忙程度。
综合美国有线电视新闻网（CNN）、Live Science网站报导，英国剑桥大学、以色列特拉维夫大学、以色列文物局（Israel Antiquities Authority）合组的研究团队，在耶路撒冷距今约2500年前的茅坑采得古人粪便样本，从中发现梨形鞭毛虫（Giardia duodenalis）遗迹。
对于考古学家而言，古人的粪便是丰富的数据库。前人透过这类研究已知铁器时代的欧洲先民喜欢吃蓝纹干酪，揭开北大西洋法罗群岛（Faroe Islands）居住的神秘族群，发现英国巨石阵（Stonehenge）的建造者常吃牛内脏。
痢疾有「旅行者腹泻」之称，人类感染梨形鞭毛虫会拉肚子、腹部绞痛、发烧、体重减轻，在医学与科学尚未发达的古代可能致人于死。现代感染梨形鞭毛虫而死亡的个案绝大多数是儿童，长期感染会导致儿童发育不良、认知能力受损、生长迟缓。
古代美索不达米亚的医疗文献显示，距今3000年至4000年前有痢疾纪录。考古界曾在古罗马时期的土耳其境内、中世纪的以色列发现梨形鞭毛虫遗迹，不过这次在耶路撒冷古人粪便样本分析出的梨形鞭毛虫遗迹，则是距今最久远的时间点。2500年前的耶路撒冷是亚述帝国境内政治与宗教中心，本次研究从两处分属当时不同菁英阶级家庭的石制坐式茅坑着手，从茅坑底下的沉积物样本获得重大发现。
研究报告第一作者是剑桥大学考古系名誉研究员米契尔（Piers Mitchell）。他说：「痢疾会经由粪便污然的饮用水与食物传播，我们怀疑这在古代的近东地区城市是严重问题，这些城市人口稠密、气候炎热，苍蝇也多，夏季用水很有限。」当时耶路撒冷到底多少人得了痢疾，无法以这次研究样本判断，仅能推估茅坑使用者可能包含住宅内的家庭成员与仆佣。
这次采集粪便样本的2个坐式茅坑之一，位于耶路撒冷以南一处古人豪宅，2019年出土，以石灰岩打造，表面凿出下凹的弧度以利坐用，中央有一个大型的圆洞，应该是供如厕者排便，另有一孔可能是供男性小便之用。另一处茅坑设计与前一个类似，出土地点在耶路撒冷旧城区一处有7个房间的古建物，推断是古时某个上流阶级家庭住所。2个茅坑出土时均安置于原位、并无迁移痕迹，年代介于公元前7世纪至6世纪，相当于犹大王国玛拿西王（King Manasseh）统治时期。
研究报告指，科学家先前在这2处古人茅坑沉积层已发现4种寄生虫的虫卵，包括绦虫、蛲虫、蛔虫、鞭虫。但引发痢疾的微生物很脆弱，非常不容易找到。
为克服这个难关，研究团队利用「酵素免疫分析法」（ELISA）生物分子技术，让抗体与单细胞有机体独有的蛋白质结合。研究人员测试了痢疾阿米巴原虫（Entamoeba）、梨形鞭毛虫与隐孢子虫（Cryptosporidium）3种最常引发人类痢疾的寄生虫，其中仅有梨形鞭毛虫出现阳性反应。
研究人员指出，中东是世界上人类最早建立定居地、学习农耕、圈养动物的地区，也出现了人类历史上最早的大型城镇与城市。古代的耶路撒冷这类大城很可能是爆发疾病疫情的热点，商贾、远征军队出入城市很容易造成疾病传播，「铁器时代中东各地城市的确已有附带集粪坑的厕所，然而在当时算是相对少见，通常只有菁英阶级才用得起。那个年代的城镇规划与兴建不包括污水系统，冲水式马桶尚未发明，当时人们并不知道有微生物存在，也不知道微生物用什么方式传播」。
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