Tuberculosis in the Americas: Current perspectives • 165 



The distribution and prevalence of the tuberculosis-like 

 pathology recognized in the Americas during pre-Columbian 

 times may, however, have been influenced by the environ- 

 mental mycobacteria. In this light, it is instructive to note that 

 when the larger skeletal series represented in Table 1 are 

 considered, relatively low population frequencies for tuber- 

 culosis occur in the southeastern United States, at Irene 

 Mound and Moundville. Recent laboratory surveys of isolate 

 distribution and frequency for the nontuberculous mycobac- 

 teria describe the Southeast as having high isolate fre- 

 quencies for M. avium. M. fortuitum, M. kimsasii, and M. 

 scrofulaceum (Falkinham et al. 1980; Good 1980; Good and 

 Snider 1982). Inreaction to the Clark etal. (1987) argument, 

 Powell has implicated cross-immunity due to the presence of 

 environmental mycobacteria to explain the "low visibility" 

 of tuberculosis at Moundville (Powell 1988:180). Although 

 incomplete archeological recovery may be cited in the 

 Moundville example, the possibility that the distribution of 

 atypical mycobacteria may have influenced the prevalence of 

 prehistoric tuberculosis-like pathology should be considered 

 in studies of ancient disease in the New World. 



Clark et al. (1987) call attention to the presence of less 

 virulent strains of tuberculosis that occur in India ("south 

 Indian variant"), in other parts of south and southeast Asia, 

 and in Africa. Such geographic variability underscores the 

 flexibility of the pathogen-host relationship and is a topic 

 worth considering further. It would be of interest, for in- 

 stance , to discover the degree to which osseous lesions devel- 

 op in these nonvirulent, pervasive forms. Certainly extensive 

 skeletal involvement has been reported for victims of tuber- 

 culosis in India (Ganguli 1963). It would also be appropriate 

 to implement McGrath's simulation approach using variables 

 specified according to the parameters common to the less 

 virulent forms. 



North American model 



The recent case studies of the North American tuberculosis- 

 like pathology reported in Table I expand the earlier sum- 

 mary presented by Buikstra (1977:326). Although certain 

 examples fit expectations more tightly than others, it appears 

 that there is now sound evidence for disease in eastern United 

 States population centers such as the Cumberland Basin, the 

 central Mississippi valley, and southern Ontario. Typical 

 skeletal expressions of tuberculosis-like pathology are de- 

 scribed in multiple individuals from several sites, including 

 Norris Farm #36, Schild Mississippian Cemetery, Mound- 

 ville, Averbuch, and in the Ontario ossuaries reported by 

 Hartney (1981) and Pfeiffer (1984). With the exception of 

 an isolated lesion in a thoracic vertebra from the Serpent 

 Mounds (Anderson 1968), a single case from an Archaic 

 shell mound (Rathbun et al. 1980), and an Illinois example 

 from uncertain context reported by Morse (1969:502) and 

 Ortner and Putschar (1981:173), these skeletal series post- 

 date A.D. 1000. Although uneven sex ratios occur in certain 



Zagreb Paleopathology Symp. 1988 



contexts, both males and females, as well as all age groups, 

 are represented. In the Schild and the Averbuch cases, the 

 classic Pott's disease occurs in young adults. Healed cases, 

 as at Irene Mound (Powell 1990), tend to be found in older 

 individuals; disease active at the time of death is associated 

 with juveniles and younger adults. 



Plains and the Southwest examples have increased in re- 

 cent years. Although the sample size is small, they neverthe- 

 less suggest a slightly earlier presence than in the eastern 

 examples. Only one, however, cleariy predates a.d. lOCK): 

 the Kayenta adolescent reported by Suinner (1985). 



The frequency data for the North American skeletal series 

 is somewhat enigmatic when viewed from the perspective of 

 modem clinical samples. When the larger, best preserved, 

 and well-excavated series reported in Table 1 and in Buikstra 

 (1977) are considered, percentage values range from the 

 Moundville (5.2%), Irene Mound (5.7%) and Schild Ceme- 

 tery (6.7%) figures to 12.1% for the Norris Farm #36 site. 

 (The Averbuch frequency may also be as high as 6. 1%, but 

 this is difficult to interpret since Kelley and Eisenberg (1987) 

 apparently include individuals with periosteal remodeling in 

 long bones in the absence of other pathognomic lesions. ) The 

 oft-cited figures of 5-7% bony involvement in modem hos- 

 pital samples (Steinbock 1976:175,1987:55), even tempered 

 by Kelley and Micozzi's (1984) observations in the Hamann- 

 Todd collection, suggest that virtually every member of these 

 late prehistoric communities had primary exposure to tuber- 

 culosis, as suggested by Klepinger ( 1987:52). In situations of 

 extreme social and biological stress, such as that reported by 

 Milner et al. (1988) for the Norris Fami #36 population, 

 prevalence of chronic destructive disease appears to have 

 been extreme. 



South America 



Allison and co-workers (1973; 1981) have reported a series 

 of 12 remains from Peru and Chile that they consider to be 

 expressions of tuberculosis. Of these, three (1981, cases 4,5 

 and 9) could be postcontact. The diagnosis of the cranial 

 granuloma in case 1 1 (Allison et al. 1981:51) is sufficiently 

 problematic that it will also be excluded from discussion 

 here. Of the remaining eight prehistoric examples, four show 

 skeletal involvement, three without confirming soft tissue 

 pathology. The remaining four are diagnosed based upon 

 healed Ghon complexes (cases 2 and 8) and cavitary pulmo- 

 nary disease in association with acid-fast bacilli (cases 6 

 and 7). 



The examples with skeletal involvement include one juve- 

 nile 8- 10 years of age. two males: one listed as 4 1 -H years of 

 age and another "adult," and an isolated female 40 years old. 

 Those diagnosed through soft tissue include the 8-IO-year- 

 old juvenile with Pott's disease, a 14-year-old female, a male 

 adult, and two females: 50 and 56+ years old. Thus, there 

 are two juveniles and four middle-old adults. Individuals 

 dying within the young adult years are conspicuously absent 



