Paleopathological study on 

 infectious diseases in Japan 



Takao Suzuki 



1 oday's clinical features of infection including its inci- 

 dence, symptoms, course, and pathological morphology in 

 living tissues have been dramatically changed by the wide- 

 spread use of antibiotics after World War II. Inflammatory 

 changes commonly found in archeological skeletal remains 

 provide good evidence of the vivid reaction of extrinsic in- 

 sults to the bone. However, it is not necessarily easy to diag- 

 nose the precise, causative disease producing such inflam- 

 matory changes based on the morphological features. On this 

 point, Putschar ( 1966:59-60) stated as follows: 



Inflammatory bone lesions pose much more serious diag- 

 nostic problems and therefore deserve more detailed discus- 

 sion. Periosteal deposition of bonewith or without 

 thickening and architectural change of the underlying cor- 

 tex of the diaphysis of long bones is probably the most 

 common inflammatory lesion found in prehistoric material. 

 The lesion often appears to be in a chronic or healed stage, 

 and it is frequently impossible to ascertain whether the 

 changes arc traumatic or infectious in origin. 



In the present study, inflammatory lesions appearing in ar- 

 cheological skeletal materials have been examined mac- 

 roscopically and categorized in order to use them as an in- 

 dicator of the health status in earlier populations. The 

 procedure of this study deals with the classification of the 

 inflammatory lesion in terms of gross morphology, and its 

 limitations and availability in reconstructing a pattern of 

 health. Even the equivocal lesions existing between non- 

 specific and specific disease, which may be an unavoidable 

 problem in paleopathology, have been considered as a part of 

 the available information for epidemiological analysis. 



In this context secular changes regarding the frequency of 

 infectious diseases in the skeletal populations in Japan have 

 been examined and interpreted with respect to biocultural 

 background. Among specific diseases, tuberculosis and 

 syphilis have been extensively studied. These two diseases 

 are viewed from the standpoints of origin, dissemination and 

 prevalence in the Japanese archipelago. 



128 



Geographic, tiistoric, and archeological 

 background 



The Japanese archipelago is made up of four main islands 

 (Honshu, Shikoku, Kyushu, and Hokkaido) which together 

 with more than 4000 smaller islands lie off the east coast of 

 Asia showing a crescent shape. The climate of these islands, 

 ranging from subfrigid to subtropic, is mostly a temperate 

 and oceanic type with four distinct seasons. More than 60% 

 of the land is mountainous, and most of this is covered with 

 forests. All of these environmental factors may have a con- 

 nection with the diseases of the inhabitants as well as the 

 ecological, biological, and sociological factors. 



The origin of the Japanese people is not altogether clear 

 with respect to location and time. However, paleolithic stone 

 implements suggest that their ancestors inhabited these is- 

 lands for more than ten thousand years. The beginning of the 

 Japanese neolithic period, Jomon, is still controversial and 

 unproven to many anthropologists. However, this prehistoric 

 period lasted at least several thousand years, and ended at 

 about the third century B.C. The main subsistence strategies 

 during the Jomon period were hunting, fishing and gathering. 

 The Jomon people made a lot of clay utensils including pot- 

 tery characterized by cord-marking (Jomon). The Jomon 

 people were buried under shell mounds which have protected 

 their skeletal remains from volcanic and acid soil. 



During the Eneolithic period, Yayoi (third century B.C. to 

 about third century a.d.), which followed the Jomon period, 

 a large number of immigrants migrated to the western part of 

 Japan via the Korean Peninsula. Immigrants mixed with the 

 Jomon people who were aboriginals in this area. It was dur- 

 ing this period that the Japanese mastered the art of rice 

 cultivation, began to use metal implements, and set the fun- 

 damental pattern of Japanese tradition and life. From the 

 paleopathological point of view, some new infectious dis- 

 eases seem to have been transmitted from the Asian continent 

 to Japan with such a huge numberof immigrants at that time. 

 According to the traditional history of Japan, the migration 



Zagreb Paleopathology Symp- 1988 



I 



