Guest post written by Anna Perman (Science Media officer, BioMed Central) with contributions from Domenico Otranto, Felipe Dantas -Torres and Jean-Bernard Huchet.
It may not be the most attractive thing ever, but this 2000 year old tick is actually looking surprisingly good for its age, thanks to its mummified host.
In research published today in Parasites and Vectors, Domenico Otranto and colleagues have described that the oldest known example of ticks on a host animal, found on a mummified dog from ancient Egypt and published last year by Huchet, Callou and other colleagues (Muséum National d’Histoire Naturelle, Paris, France), probably belong to the so-called temperate species (or southern lineage) of the Rhipicephalus sanguineus group. By examining the ticks, the authors formed a hypothesis about its origin and how it spreads.
Ticks are arachnids that feed on the blood of animals. They are a major carrier of disease-causing parasites in both humans and in dogs, and so the specimens could be useful for scientists looking at the kind of diseases the ticks carried in ancient Egyptian times, and how they crossed over into humans.
Domenico Otranto from the University of Bari says: “This finding indicates that Rhipicephalus sanguineus has a long history of parasitism with dogs and it raises interesting questions about their spread throughout the Mediterranean region with people moving in ancient times from North Africa after the collapse of the Roman Empire or, even before, during the expansion of the Roman Empire through Eurasia.”
The mummy was buried sometime between the 1st and 4th century AD, and 61 ticks were found mummified along with their canine host, which is why they’re in such good condition now. The mummy was excavated by a French expedition in 2013 from a Roman fortress in El Deir in Egypt, and previous research published in the special series on paleoparasitology in the International Journal of Paleopathology, by Huchet et al., 2013 suggested that its cause of death might have been caused by the tick infestation, or an infection the ticks might have carried. Of the ticks found on the mummified dog, most were in its left ear, and in the research article, scientists studied five of them that were in particularly good condition.
This suggests that these ticks have been infesting dogs in the same way for 2000 years, probably transmitting the same pathogens afflicting our dogs today and gives some clues about how the parasite spread throughout the Mediterranean.
Domenico Otranto adds: “Dogs have acted as companions to humans for millennia and have many things in common with us including parasites. By increasing our knowledge of the interaction of these ticks with dogs, we can then better understand this pathogen and how to control them.”