Social networks of disease spread in the lower illinois valley: A simulation approach

Abstract

This study illustrates the use of disease modeling and simulation techniques to the study of the spread of disease within and between social networks. A Reed-Frost type model of disease spread is used to construct a simulation of the spread of tuberculosis within three prehistoric populations of the Lower Illinois River Valley during Middle Woodland, Late Woodland, and Mississippian times. A high and low population size was modeled for each time period. Late Woodland model 2 (low population estimate) is the only model that experienced pathogen extinction with host survival. The rest of the models experienced rapid and severe host population decline. The results of the simulation suggest that a social network size of between 180 and 440 persons is required under the conditions of this model for host-pathogen coexistence (i.e., endemicity) to occur. The severe population decline experienced by these populations suggests that tuberculosis as modeled here could not have existed in these populations. Future refinements of modeling and simulation techniques can provide additional insights into how disease spreads among social contacts.

Pathology of post primary tuberculosis of the lung: An illustrated critical review

“…Consequently, the continued existence of MTB depends on transmission among humans. Over many millennia, MTB has evolved a complex life cycle that allows it to persist indefinitely in human communities as small as a few hundred people 4 . This life cycle includes two distinct types of infection: primary and post primary tuberculosis in addition to prolonged periods of dormancy.…”

Strains of Mycobacterium tuberculosis from Western Maharashtra, India, Exhibit a High Degree of Diversity and Strain-Specific Associations with Drug Resistance, Cavitary Disease, and Treatment Failure

“…Under such conditions, the strain diversity is expected to be different compared to that for epidemic or sporadic incidents, where a few specific strain types dominate (8,23); in a setting where tuberculosis is endemic, the pathogen and the host are expected to evolve simultaneously for long durations, resulting in a set of varied strain types (6,20,21).…”

Tuberculosis in the New World: a study of ribs from the Schild Mississippian population, West-Central Illinois

“…However, it is important to note that lesions that resemble TB can arise from multiple causes, and such causes cannot always be differentiated. This ambiguity, together with the high prevalence of bone lesions at Schild led McGrath (1988) to argue that diseases other than TB were responsible for the Schild lesions. Thus, while we do not recommend a diagnosis of TB infection solely on the basis of the presence of periosteal reaction on ribs, we do recommend incorporating a close examination of ribs as part of a multi-pronged approach, including both morphological and molecular testing into future research on TB complex prevalence in ancient populations.…”