Bacteria in two-millennia-old cheese, and related epizoonoses in Roman populations

A tremendous volcanic eruption destroyed all the life around Mount Vesuvius during the night between 24 and 25 August, 79 AD. Two famous towns, Pompeii and Herculaneum, were completely buried under volcanic products. At Herculaneum, about 25m of volcanic mud killed about 250 people who had fled to the beaches in an attempt to escape (Bisel, S. C.,Rivista di Studi Pompeiani, 1, 123-124, 1987). An anthropological examination of the skeletons of these "fugitives" reveals the bone lesions typical of brucellosis in 17.4% of adults (Capasso, L., International Journal of Osteoarchaelogy, 9, 277-288, 1999). This very high incidence of brucellosis was theoretically linked to the consumption of ovine milk and its derivates, which is also indicated by both literary and figurative sources. A single carbonized cheese was found in Herculaneum; its analysis clearly reveals the excellent state of preservation of the milk curds. For the first time, we demonstrate the presence of a variety of bacteria, possibly Lactobacillus, that also includes cocco-like forms that seem to be morphologically and dimensionally consistent with Brucella. The long interval spent by the organic remains under the volcanic mud and high temperatures they suffered preclude the possibility of identifying the bacteria through molecular methods.