Abstract

Setting: The underlying trends in the past epidemiology of tuberculosis (TB) are obscure, requiring recourse to the archaeological record. It would therefore be of value to develop methods for reliable {TB} diagnosis in ancient populations. Objective: To test the capability of two biomarkers, Mycobacterium tuberculosis complex mycolic acids and a {DNA} target (IS 6110), for confirming an osteological diagnosis of {TB} in medieval individuals, based on the presence of Pott's disease and/or rib lesions. Design: Osteological examination of three archaeological individuals (Medieval: �1000 years old) revealed a Pott's disease case, one with no changes consistent with {TB} and one with rib lesions. Rib samples from these individuals were examined for the presence of Mycobacterium tuberculosis complex mycolic acids and mycobacterial DNA. Results:Mycobacterium tuberculosis complex mycolic acids and the {DNA} target were detected in the Pott's disease case, whilst mycolic acids (insufficient for confirmation) alone were detected in the rib lesion case. Conclusions: Biomarkers provide a sensitive tool to detect ancient TB. Mycobacterium tuberculosis {DNA} is not distributed homogeneously, making multiple sampling essential. Mycolic acids seem more reliable for ancient {TB} diagnosis than {IS} 6110. The demonstrated stability of mycolic acids show that they may be of value in tracing the palaeoepidemiology of tuberculosis back into antiquity.