Diagnosis and Evaluation of Causative Factors for the Presence of Endemic Treponemal Disease in a Japanese Sub-Tropical Island Population from the Tokugawa Period
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See discussions, stats, and author profiles for this publication at: https://www.researchgate.net/publication/276293929 Diagnosis and evaluation of causative factors for the presence of endemic treponemal disease in a Japanese sub-tropical island population from the Tokugawa period Article in International Journal of Paleopathology · September 2015 DOI: 10.1016/j.ijpp.2015.04.001 CITATIONS READS 3 393 2 authors: Mauricio Hernandez Mark J. Hudson University of California, Los Angeles Max Planck Institute for the Science of Human History 4 PUBLICATIONS 4 CITATIONS 106 PUBLICATIONS 610 CITATIONS SEE PROFILE SEE PROFILE Some of the authors of this publication are also working on these related projects: Asia and the Anthropocene View project Millet and beans, language and genes. The dispersal of the Transeurasian languages View project All content following this page was uploaded by Mark J. Hudson on 28 May 2018. The user has requested enhancement of the downloaded file. International Journal of Paleopathology 10 (2015) 16–25 Contents lists available at ScienceDirect International Journal of Paleopathology j ournal homepage: www.elsevier.com/locate/ijpp Diagnosis and evaluation of causative factors for the presence of endemic treponemal disease in a Japanese sub-tropical island ଝ population from the Tokugawa period a, b Mauricio Hernandez ∗, Mark J. Hudson a Division of Biological Anthropology, Department of Archaeology and Anthropology, University of Cambridge, Cambridge CB2 3DZ, United Kingdom b Research Institute for Sustainable Environments and Cultures, Nishikyushu University, Kanzaki 842-8585, Japan a r t i c l e i n f o a b s t r a c t Article history: We present a description and differential diagnosis of pathological lesions observed on skeletal ele- Received 1 June 2014 ments found during surface surveys of the Nagabaka site on Miyako-jima Island, Japan. The Nagabaka Received in revised form 5 April 2015 site served as a bone depository during the Early Modern period (c. AD 1600–1870). We evaluated remains Accepted 6 April 2015 via macroscopic inspection to classify infectious lesions according to criteria in Weston (2008). We also obtained CT scans of three bone elements for more extensive lesion analysis and carried out a differential Keywords: diagnosis utilizing paleopathological literature. Subsequent investigation yielded convincing evidence Yaws of treponemal infection on 23 skeletal elements. Based on known geographical spread and morpholog- Treponemal disease Paleopathology ical comparisons of lesion patterning, we identified yaws as the pathogen most likely responsible, but refrained from calculating site-wide prevalence due to the taphonomical nature of the sample. Lastly, we Ryukyu Islands Japan review treponemal infection rates in other archaeological sites throughout Southeast Asia and Oceania, and assess similar ecological and cultural factors contributing to the observed pathologies. Nagabaka is the northernmost site in the world where yaws has so far been identified. Located between sites between Mainland China and Western Micronesia where this infection has been previously identified, Miyako-jima holds an important geographical position for research into the historical spread of pathogens. © 2015 Elsevier Inc. All rights reserved. 1. Introduction Miyako-jima is the largest of the Miyako Islands, located approx- imately 270 km southwest of Okinawa Island. It forms part of a The global history of treponemal disease is constantly being chain of islands stretching from Taiwan to Kyushu, collectively refined with new temporal and geographic data points emerging known as the Ryukyu Islands (see Fig. 1). Miyako-jima is triangular 2 through ongoing research in the fields of archaeology, paleopathol- in shape, with a total area of approximately 158.70 km . The island ogy, history and genetics. During the course of surface surveys and is largely flat, with a maximum elevation of only 115 m above sea excavation at the Nagabaka site on Miyako-jima, Japan, we discov- level. At present, the terrain is mostly covered with arable fields and ered evidence that could extend the geographic range of infection the principal cash crop is sugarcane for brown sugar production. prevalence northeast, into Japanese territory. This paper reports the The climate of Miyako-jima is considered to be sub-tropical due to site context and procedures we used to define most probable dis- the warm waters of the Kuroshio ocean current that passes through ease identification, including both macroscopic and radiographic this region, known as the Indomalaya eco-zone. Since Medieval analysis, along with an extensive differential diagnosis. times, Miyako-jima has been home to speakers of Ryukuan lan- guages who likely migrated south from Japan (Pellard, 2015). The Nagabaka site located at 24◦ 51# N, 125◦ 17# E in the Shimajiri district of northern Miyako-jima. It is situated within 50-m long ଝ rock shelter, which rests on a ridge approximately 26–27 m above Grant Sponsorship: Grant-in-aid for Scientific Research on Innovative Areas, MEXT, Japan for the project ‘Environmental and cultural changes in the Ryukyu sea level within a densely wooded area. This rock shelter was used archipelago during prehistoric and proto-historic times’ (No. 21101005), Downing as a depository for human remains during the Early Modern era. College Graduate Travel Grant, Ridgeway-Venn Travel Studentship, Worts Traveling Although artifacts found at the site suggest that its main period of Scholar Fund, and JSPS Core-to-Core Program. use occurred during the 17–18th centuries, some skeletons may ∗ Corresponding author at: Downing College, Regent Street, Cambridge CB2 1DQ, date as late as the 19th century (Nagabaka Archaeology Project, United Kingdom. Tel.: +44 7494 360 251; fax: +44 1223 764 710. E-mail address: mh608@cam.ac.uk (M. Hernandez). 2013). http://dx.doi.org/10.1016/j.ijpp.2015.04.001 1879-9817/© 2015 Elsevier Inc. All rights reserved. M. Hernandez, M.J. Hudson / International Journal of Paleopathology 10 (2015) 16–25 17 Fig. 1. Regional map of the Ryukyu Islands and the location of Miyako-jima. Inset shows the location of the Nagabaka site within the island. Nagabaka is composed of three sections (running north to south) broken epiphyses due to taphonomic processes including animal demarcated by low limestone-block walls that prevent the skele- activity, and several have been stained green from algae growth. tal remains and accompanying cultural implements from rolling Lastly, a small percentage of remains also display mineral deposits down the ridge. The North and South sections of the site where from being under driplines, which indicates that the site, as well as most skeletal remains are found are the longest, measuring approx- the remains, are largely undisturbed. imately 23 m each. An overhanging rock shelter covers the South The Nagabaka site is an example of a type of cemetery known and Central sections (see Fig. 2), whereas the overhang in the in the Ryukyu Islands as a fus¯ obo¯ or fus¯ obaka¯ , terms with the lit- North section is less pronounced, making it more open to the ele- eral meaning of “wind burial”. Corpses were deposited in caves ments. Within each section of the site, there are many scattered or rock shelters and left until the flesh decayed, a process that human remains, both exposed and partially buried. Bone preserva- was often accelerated by hermit crabs. Once the flesh was gone, tion varies, depending on location within the rock shelter. Bones bones were often placed in ceramic urns or wooden coffins. No within the North section are generally more weathered, whereas such ceramic urns are present at Nagabaka. Pieces of wood found in the Central and South sections, they generally display good cor- in the North and South sections of the site are likely to be fragments tical preservation, as they are protected from direct sunlight and of the boat-shaped coffin mentioned by Ikeda (1974). However, it the low overhang helped to maintain humidity and soil moisture. seems unlikely that all of the skeletal remains from Nagabaka were About 60–70% of long bones have partially damaged or completely originally contained in just one coffin, suggesting that the method Fig. 2. Map of the Nagabaka site showing the shelter’s North, Central and South sections, as well as the retaining wall. Inset A – South section viewed from the north. Inset B – southern portion of the North section. Inset C – adjacent area of the North section. Photos taken during fieldwork in July, 2012. 18 M. Hernandez, M.J. Hudson / International Journal of Paleopathology 10 (2015) 16–25 Table 1 Distribution of major skeletal elements at the Nagabaka site divided by section and side. Bone North Central South L/R L/R L/R Cranium 75 16 88 Mandible 32 5 30 Humerus 34/16 2/4 38/43 Radius 11/10 0/2 16/9 Ulna 9/8 1/0 29/17 Femur 56/61 6/4 68/47 Tibia 46/51 5/3 52/64 of body disposal varied and the site may have been used for both primary and secondary body disposal. No historical records of the Nagabaka cemetery are known and current residents of the island do not consider themselves related to the individuals deposited within the shelter. Although we cannot verify the identity of the commingled remains at Nagabaka, as Ikeda (1974) notes, the gen- erally isolated history of Miyako-jima makes it almost certain that these skeletons represent the local population in the early modern period. 2. Materials Since the early 1970s, all three sections of the Nagabaka rock shelter have been subject to anthropological investigation by several scholars (Ikeda, 1974; Dodo et al., 1998, 2000, 2001; Pietrusewsky, 1999). Recently, fieldwork was conducted by M.J. Hudson in nine annual seasons from 2005 to 2013. A 2010 surface survey of all the commingled remains at the site, led to the inference that the site’s three sections house a minimum of 172 individuals (Nagabaka Archaeology Project, 2013).