I’ve been meaning to mention this ever since the article was published in PLoS One.
Brucellosis is an infectious disease caused by any of several bacilli. It is primarily found in livestock such as cows, horses, pigs, and goats. It has also been found in wild animals such as zebra, eland, waterbuck, and impala. It is primarily transmitted to humans via infected dairy products and meat. In humans the disease appears as a chronic infection of the lungs and recurring fevers. Males are affected more than females. The primary center of skeletal involvement occurs in the spine. Ortner and Putschar define the lesion involved as follows:
The lesion is a lytic cavitation. Grossly and on X-ray, it frequently can be seen penetrating the vertebral end-plate and extending through the nucleus pulposus of the disc into the next vertebral body … The cancellous bone within the focus is destroyed without formation of significant sequestra. The cortex also may be perforated, leading to parosteal abscesses. There is usually very little, if any, reactive bone formation except in the healing phase … In contrast to tuberculosis, which it resembles in several ways, complete collapse of vertebrae with gibbus formation is usually not observed … and paravertebral abscess is rare …
Incidents of trauma, malformations, and degenerative changes have been identified in Australopithecus afarensis (the AL 288-1 vertebrae) and Homo erectus/ergaster (KNM-ER 1808 with hypervitaminosis, Trinil femur with, possibly, myositis ossificans) but infectious diseases, as far as I know, have been absent. Enter STW 431, a 1.5 – 2.8 MYA skeleton, attributed to A. africanus, comprised of the pectoral girdle, upper limbs, and pelvic girdle. Additionally, vertebrae from T9-L5 are present. The vertebral material has been the focus of some attention in the past. Both L4 and L5 have lesions previously attributed to spondylosis deformans. The PLoS study took a fresh look at the subject.
Based on examination via stereomicroscope and scanning electron microscope the authors of the paper rule out tuberculous and staphylococcic spondylitis. Degenerative processes were ruled out due to the fact that none of the other bones displayed any signs of degenerative processes. Originally, the lesions had been attributed to spondylosis deformans caused by trauma. This was ruled out in the current study because, the authors argue, the lesion bears the characteristics of an inflammatory process. Brucellosis could have been acquired from scavenging of infected meat. Although the case was not conclusively proven, the paper presents an interesting and suggestive analysis.
D’Anastasio R, Zipfel B, Moggi-Cecchi J, Stanyon R, Capasso L, 2009 Possible Brucellosis in an Early Hominin Skeleton from Sterkfontein, South Africa. PLoS ONE 4(7): e6439. doi:10.1371/journal.pone.0006439
Ortner and Putschar 1981 Identification of Pathological Conditions in Human Skeletal Remains. Smithsonian Contributions to Anthropology, number 28