VN February 2023

Vetnews | February 2023 39 The study of ancient diseases is not an easy task. To the difficulty in finding and recovering suitable biological samples, data loss and other problems, we must add the little interest traditionally given to non-human remains in archaeological sites. To face this challenge, different disciplines (archaeo-zoology and paleo-parasitology), supported by Molecular Biology techniques (archaeo-genetics), must be combined (see figure). Skeletal remains are an important source of information. Morphological analysis of hard tissues, not only bone but also teeth, allows the diagnosis of certain pathologies. In the case of brucellosis and tuberculosis, primarily manifesting as respiratory diseases, secondary infections can occur in bone and other tissues. Molecular identification must be performed todistinguish themfromother pathologies with the same bone lesions (malignant neoplasm, trauma, etc.),. The earliest secure evidence of brucellosis disease in hominid evolution was found in the man of La Chapelle, 50 000 B.C., in a time when mammoths and woolly rhinos were the reservoirs. In the case of tuberculosis, the biomolecular analysis showed that it was present at least 70 000 years ago in the early human populations of Africa. Other pathogens can be traced back by DNA analysis: Salmonella enterica from the Neolithic times and Yersinia pestis , responsible for some of the most destructive pandemics in history. Pathogens can also be detected during macro and microscopic examination of soft tissues. The eggs of a great diversity of parasites are easily preserved in mummified tissues where diseases such as trichinosis, cysticercosis, taeniasis and trichuriasis can be detected. Another source of biological samples is soil. It is the main reservoir for Bacillus anthracis, whose spores can survive for hundreds of years. This bacterium isolated from old bones in the Kruger National Park could help us understand this lethal disease’s cyclical outbreaks. Identifying parasites in animal and human coprolites is also an important tool of study, not only of the living conditions and health of ancient populations thousands of years ago but also ancient parasitoses. Fossilized vectors are also important in understanding the evolution of diseases and hosts by investigating their mutual influence and co-evolution through time. Last but not least, we have textual sources in which we can read about epidemics and descriptions of diseases and their symptoms: rabies in the Eshnunna Code (1930 B.C.), hydatid disease in the Hippocratic Corpus (V-IV B.C.), scabies in the Old Testament and Aristotelian Corpus, etc. And if the disease has distinctive external characteristics, it could even be depicted in art (for example, facial mutilations compatible with leishmaniosis in early pre-Columbian American art). Zoonoses are present today as they were in the past. A holistic approach in which different scientific and humanistic disciplines complement each other and allow the establishment of a dialogue between the past and present is needed in order to complete our current knowledge of these diseases and their evolution, and here Veterinary Science has a lot to contribute. v ZOONOSES IN ANTIQUITY: WHAT DOWE KNOW? AND HOW DOWE KNOW? Silvia Nicolás Alonso Ph.D. in Veterinary Medicine Biblical and Oriental Institute (León, Spain) Do you Know? TThe so-calledNeolithic Revolution implieda radical change inhuman-animal relationships. Population growth, people concentrated inpermanent settlements, animal husbandry inhuman environments and lackof proper sanitation systemswere the newscenarios for novel disease outbreaks, zoonoses among them. Their study fromdifferent historical times in several parts of theworldallows us toachieve adeeper understandingof their development. It helps us todesign strategies todeal with them. Biologic samples: where and what. Recently developed techniques allow us to trace back to ancient diseases. Source: compiled by the author.