Dr. Rajesh Karyakarte MD

Professor and Head,

Department of Microbiology,

Government Medical College, Akola

Maharashtra, India

PALEOPARASITOLOGY

WHAT IS PALEOPARASITOLOGY?

• Paleoparasitology is the study of parasites and their interactions with hosts and vectors, from the past

• Paleoparasitology can also be defined as the study of parasites in archaeological material

• Paleoparasitology is a subfield of Paleontology – the study of living organisms from the past

ALTERNATIVE TERM

• Archaeoparasitology: the study of parasite evidence from archaeological sites

• Reinhard further suggested that "the term 'Paleoparasitology' be applied to studies of nonhuman, paleontological material." i.e., the study of the parasites of non-human animals and plants from the past, while study of parasites from humans and our hominid ancestors are covered in archaeoparasitology

WHEN DID IT BEGIN?

• It began when Schistosoma haematobium eggs were found in infected kidneys of Egyptian mummies in 1910

Ruffer MA 1910. Note on the presence of Bilharzia haematobia in Egyptian mummies of the Twentieth Dinasty (1250-1000 BC). Br Med J 1: 16.

FROM WHERE DO YOU GET THE SAMPLES?

• It is believed that parasites do not leave fossils behind

• Nevertheless parasitic remains have been found in 1.5 million years old paleontological sites, as well as in 500,000 years old preserved organic material

FROM WHERE DO YOU GET THE SAMPLES? CONT.….

• Paleoparasitology samples are found in environments where preservation is best :

• Moist anaerobic environment – Latrines

• Desiccating environment – caves and

rock-shelters in arid regions

Reinhard K, Confalonieri U, Ferreira LF, Herrmann B, Araújo A 1988. Recovery of parasite remains from coprolites and latrines: aspects of paleoparasitological technique. Homo 37: 217-239.

OTHER SOURCES

• Fossils,

• Amber inclusions,

• Hair,

• Skins, and

• Feathers

WHAT ARE COPROLITES?

• Coprolites are desiccated or mineralized feces

• Special techniques are used to search for parasites in coprolites

• Rehydration of desiccated coprolites with a trisodium phosphate solution is required before the search for parasites (Callen & Cameron 1960)

• Modified pollen analysis techniques are used for fossilized coprolites (Reinhard et al. 1985)

Callen EO, Cameron TWM 1960. A prehistoric diet as revealed in coprolites. New Sci 8: 35-40.Reinhard KJ, Ambler JR, Mcguffie M 1985. Diet and parasitism at Dust Devil Cave. Am Antiquity 50: 20-24.

FROM WHERE DO WE RECOVER COPROLITES?

• Coprolites can be recovered from :

• Archaeological layers or cesspits, and

• Directly from mummified bodies

• They are the main source for parasite remains

FROM WHERE DO WE RECOVER COPROLITES?

• To summarize:

• Desiccation and mineralization of coprolites results in excellent preservation of parasite larvae and eggs

• It is important to note that

• Protozoan cysts are rarely found in coprolites (Ferreira et al. 1992)

FROM WHERE DO WE RECOVER COPROLITES? CONT.….

• Helminth species that normally hatch out of their eggs and leave feces are trapped by drying of coprolites, providing records of :

• Hookworm (Araújo et al. 1981, Ferreira et al. 1987) and

• Strongyloides infection in ancient humans (Reinhard et al. 1987)

WHO WERE THE PIONEERS?

• Cockburn (1967) was the first person to call attention towards study of parasites in coprolites, and

• This new field of science, Paleoparasitology, was named by Ferreira et al. (1979)

Cockburn A 1967. Infectious Diseases: their Evolution and their Erradication, Charles Thomas Publ., USA.Ferreira LF, Araújo A, Confalonieri U 1979. Subsídios para a paleoparasitologia do Brasil: parasitos encontrados em coprólitos no município de Unaí, MG. An V Congr Soc Bras Parasitol, p. 66.

EVIDENCE OF PALEOPARASITISM

• Helminths caught in amber during the process of escaping from the body of an insect,

• Lice found in the fur of guinea pig mummies,

• Protozoans found in the alimentary canal of flies caught in amber,

• Nematode larvae found embedded in animal coprolites, and

• Mite caught in amber during the process of apparently feeding on a spider.

WHAT DO WE FIND WITH THE HELP OF PALEOPARASITOLOGY?

• Paleoparasitology and especially molecular paleoparasitology offer new tools for the study of ancient host-parasite relationship – its origin and evolution

WHAT DO WE FIND WITH THE HELP OF PALEOPARASITOLOGY?

• Paleoparasitology helps in interpreting archeological findings and making inferences about the impact of parasitic diseases among prehistoric populations

Reinhard KJ 1992. The impact of diet, and parasitism on anemia in the prehistoric West. In P Stuart-McAdam, S Kent (eds), Demography and Disease: Changing Perspectives of Anemia, Aldine deGruyter, New York, p. 219-258.

WHAT DO WE FIND WITH THE HELP OF PALEOPARASITOLOGY?

• In this regards, hunter-gatherers were found to be less infected by helminths

Reinhard KJ 1992. The impact of diet, and parasitism on anemia in the prehistoric West. In P Stuart-McAdam, S Kent (eds), Demography and Disease: Changing Perspectives of Anemia, Aldine deGruyter, New York, p. 219-258.

WHAT DO WE FIND WITH THE HELP OF PALEOPARASITOLOGY?

• Agricultural groups showed comparatively higher prevalence of intestinal parasites in archaeological sites in the United States

Reinhard KJ 1992. The impact of diet, and parasitism on anemia in the prehistoric West. In P Stuart-McAdam, S Kent (eds), Demography and Disease: Changing Perspectives of Anemia, Aldine deGruyter, New York, p. 219-258.

WHAT DO WE FIND WITH THE HELP OF PALEOPARASITOLOGY? CONT.....1

• The finding of Diphyllobothrium pacificum eggs, a sea lion parasite, in human coprolites dated of 6,000 years before present (B.P.) told us about the food habits of prehistoric inhabitants in the Chilean desert.

Ferreira LF, Araújo A, Confalonieri U, Nuñez L 1984. The finding of Diphyllobothrium in human coprolites (4,100-1,950 BC) from northern Chile. Mem Inst Oswaldo Cruz 79: 775-780.

WHAT DO WE FIND WITH THE HELP OF PALEOPARASITOLOGY? CONT.....2

• Heirloom parasites are well exemplified by Enterobius vermicularis studies:

• This helminth infection was recorded in North America dated up to 10,000 years B.P.

• E. vermicularis infection was found in cold climates, in Greenland, dated 1400 A.D. (Anno Domini), and

• In the South American Pacific coast from 4,000 to 2,000 years B.P.

WHAT DO WE FIND WITH THE HELP OF PALEOPARASITOLOGY? CONT.....3

• Paleoparasitological human-parasite coevolutionary studies show:

• The antiquity of parasite-host relationships, and

• Helps in tracing the origin and dispersion of infection in prehistorical times

Confalonieri U, Ferreira LF, Araújo A 1991. Intestinal helminths in Lowland South American indians: some evolutionary interpretations. Hum Biol 63: 865-875.

PALEOPARASITOLOGY AND PALEOGENETICS CAN ANSWER QUESTIONS REGARDING HUMAN SETTLEMENT

• The finding of human hookworm and whipworm eggs in pre-Columbian America raised an interesting debate

• Both are geohelminths, with an obligatory passage in the soil

• They can only maintain their biological cycle to infect a new host if environmental conditions are suitable

PALEOPARASITOLOGY AND PALEOGENETICS CAN ANSWER QUESTIONS REGARDING HUMAN SETTLEMENT CONT.….1

• Hookworm eggs were found in human coprolites in South American archaeological sites radiocarbon dated as old as 7,200 years

• Trichuris trichiura eggs were found in the Andean region and in the other side of the continent, in Brazilian Northeast, dated 2,000 years B.P.

• In both cases, eggs were recovered from intestinal contents of South American mummies

PALEOPARASITOLOGY AND PALEOGENETICS CAN ANSWER QUESTIONS REGARDING HUMAN SETTLEMENT CONT.….2

• Prehistoric migrations of people from Arctic region cannot introduce hookworm and whipworm infection as warmth is required for soil developing larvae

• Thus, cold climate and nearly frozen conditions of the soil would have impaired larvae and eggs to evolve and be transmissible to a new host.

PALEOPARASITOLOGY AND PALEOGENETICS CAN ANSWER QUESTIONS REGARDING HUMAN SETTLEMENT CONT.….3

• Therefore, the paleoparasitological discovery of these parasites in prehistoric South America indicates that there was a non-arctic migration of humans from the Old World to the Americas.

• Paleoparasitology together with paleogenetics, is helping to sort this issue

MOLECULAR PALEOPARASITOLOGY

• In addition to the classical paleoparasitology based on coprolite rehydration and microscopic analysis after parasite concentration techniques, molecular paleoparasitology is growing as a powerful tool

MOLECULAR PALEOPARASITOLOGY CONT.….1

• Ancient DNA (aDNA) are nucleic acids recovered from archaeological material or museum specimens

• DNA can be recovered from human bones and mummified tissues

• The polymerase chain reaction (PCR) is now applied in paleoparasitological analysis

MOLECULAR PALEOPARASITOLOGY CONT.….2

• PCR was used to detect Borrelia burgodorferi in 13 of 1,036 mite museum samples in the United States, and

• For detecting Leishmania amazonensis in taxidermized rodents from museum

MOLECULAR PALEOPARASITOLOGY CONT.….3

• PCR was used to study Mycobacterium tuberculosis infection in mediaeval skeletons in Europe, in a Peruvian precolumbian mummy, and in Chilean prehistoric skeletons

MOLECULAR PALEOPARASITOLOGY CONT.….4

• Chagas disease is an excellent example for application the Molecular paleoparasitology

• Trypanosoma cruzi DNA fragments were found in South American mummies

MOLECULAR PALEOPARASITOLOGY CONT.….5

• Mummies are a scarce remain of ancient cultures, but bones can be found more abundantly

• Thus bones and skeletons of prehistoric populations are now the focus of attempts to find evidence of T. cruzi

MOLECULAR PALEOPARASITOLOGY CONT.….6

• Moreover, in most of the cases bones and skeletons are the only available material for analysis

• Molecular paleoparasitology is successful in finding traces of a parasite that are not visible under a microscopic

SUMMARY

• With the recognition of the importance of understanding parasite evolution in the control of modern diseases, paleoparasitology has a new importance

SUMMARY CONT.…..1

• The understanding of parasite evolution can be addressed by the combined approaches of paleoparasitology and molecular paleoparasitology

SUMMARY CONT.…..2

• With paleoparasitology, one can document the appearance of parasites in human prehistory

SUMMARY CONT.…..3

• With molecular paleoparasitology, one can potentially identify the change in parasite genomes that resulted from the host-parasite interaction

SUMMARY CONT.…..4

• Paleoparasitology has also helped to solve riddles in fields other than parasitology Examples include:

• Migration and phylogeography of marine mammal hosts

SUMMARY CONT.…..5

• Identity of domestic animal bones from parasite remains found at the archaeological site, and

• The effect of climatic changes on genetic diversity found in animal host

Thank you !