Origin, evolution and paleoepidemiology of brucellosis.

Brucellosis is a worldwide disease. Although it has been eradicated in some countries, it continues to be an important disease in many farming areas. Previous works have described the evolution and diffusion of brucellosis in antiquity through direct analysis of ancient human remains collected by the University Museum of Chieti, Italy, and by using paleopathological and historical data. The earliest published case was reported in a skeletal individual dated to the Middle Bronze Age. However, our research group has diagnosed vertebral brucellosis in the partial skeleton of the late Pliocene Australopithecus africanus, demonstrating that this infectious disease occasionally affected our direct ancestors 2·3-2·5 million years ago. The frequency of brucellosis increased during the Roman period, when the disease would almost certainly have been endemic in Roman society, and during the Middle Ages. Most paleopathological cases involve adult male skeletal individuals, and lumbar vertebrae and sacroiliac joints are most commonly involved.