Symposium Ancient pathogens: Paleosciences April 12th, 2016 PALEOPARASITOLOGY from Ancient to Future Míriam J. Álvarez-Martínez M.D., Ph.D. Microbiology Department Hospital Clinic, Barcelona (Spain) ISGlobal (Barcelona Institute for Global Health) School of Medicine-University of Barcelona [email protected] ESCMID eLibrary by author ESCMID eLibrary by author ESCMIDProfessors Luiz Fernando Ferreira, KarleLibrary Jan Reinhard, Adauto Araújo by author OUTLINE 1. What is Paleoparasitology? 2. Origin of Parasites in Humans • Heirloom parasites & Souvenir parasites 3. Parasites as Markers of Prehistoric Migrations 4. Preservation of Paleoparasitological Remains a) Parasites characteristics b) Microenviroments & Recovery of Parasites – Coprolites/Latrine soil /Mummified bodies 5. Techniques in Paleoparasitology: Ancient DNA (aDNA) 6. Some Paleoparasitological Studies ESCMID7. Conclusions eLibrary by author PALEOPARASITOLOGY 1 • Study of parasites in the remains of humans and other animal species recovered from archaeological or paleontological sites or any source in which they have remained preserved. • Derived from the Greek παληος (ancient) παρασιτος (next to bread) λογς (study) • Field of knowledge splitted from Paleopathology from the finding of parasite forms in archeological ESCMIDmaterial. eLibrary by author ESCMIDSir Marc Armand RUFFER (1845-1917) eLibrary by author • Sir Marc Armand Ruffer-pioneering work in 1910- publication finding of Schistosoma haematobium eggs in the kidney tissue of Egyptian mummies from the 20th Dynasty, dated to circa 1250 to 1100 BC ESCMID eLibrary by author ORIGIN OF PARASITES IN HUMANS 2 First hominids in Africa were hosts for some species of parasites. Inherited from pre-hominids or acquired from enviroment 1. Phylogenetic Route Various parasites species persisted in Homo sapiens, inherited ancestrally and originating during pre-hominid times. These parasites are also found in phylogenetically proximate hosts. 2. Ecological Route New parasites acquired from the enviroment began to infect humans as the latter conqueres new spaces , ie during the exploration of new ESCMIDterritories and contact with different eLibraryanimal species and their parasites. by author Preservation of paleoparasitologicalHEIRLOOM PARASITES remains • Some infectious agents of human disease have coevolved with species in the Homo lineage for over 400,000 years. • Most common parasites had a concomitant origin with earlier species in the human evolutionary line. • These long-term, coevolved parasites are called “Heirloom Parasites” • As humans evolved, their heirloom parasites evolved with them. • This is the case for Enterobius vermicularis (pinworm) and Pediculus humanus (head lice) Pediculus humanus found in a partially mummified Enterobius vermicularis found in a human human body, Brazil, dated of ESCMIDcoprolite dated of 6,000 years, Chile Prof. AraujoeLibrary pictures 12,000 years by author Preservation of paleoparasitologicalSOUVENIR PARASITES remains • Humans have acquired other parasites during their biological and social history, called “Souvenir parasites”. • Species that occur in humans commonly, arriving through host- switching from other animal species (animal domestication). • This was considered the origin of two species of taeniid tapeworms (Taenia saginata and T. solium) in humans that use cattle and pigs as intermediate hosts. ESCMIDPaleolithic- hunters & gatherers eLibraryNeolithic- agriculture & livestock by author PARASITES MARKERS OF PREHISTORIC MIGRATIONS 3 • Host-specific parasites of humans are used to track ancient migrations Ancient migrations to the Americas • Timing of the arrival of humans in the New World has been the focus of a long-standing and intense debate. • Accepted hypothesis that populations of prehistoric humans crossed into the Americas when climate conditions created the Bering Land Bridge at least 13, 000 years ago. • People could have reached the Americas more than 7,000 years ago using alternative routes avoiding the extreme cold of the Arctic. • From the parasitological perspective evidence shows that populations of pre-historic humans were infected by several host-specific intestinal parasites found in both North and South American archaeological sites. The life cycle of these exclusively human parasites could not have been maintained among human groups during the crossing ESCMIDfrom Siberia to Alaska via Beringia. eLibrary by author ESCMID eLibrary by author 2008 Three general migration routes of humans in prehistory hypothesized from Asia to the Americas. (a) Represents the longest-standing hypothesis of a migration route through Beringia and into North America at the time of low sea level and glacial maximum (b) Parasite probe data are consistent with a Coastal migration or ESCMID(c) Trans-Pacific migration eLibrary by author • Climate and soil temperature are limiting factors for human hookworm and whipworm, being host-specific and without intermediate hosts. • High soil moisture and moderate temperature are necessary for eggs or larvae to reach the infective stage. • Eggs of E. vermicularis are infective as soon as they are expelled from female worms; in the external environment, they can infect humans immediately through contaminated hands, soil, water, any kind of object or as an aerosol. • Therefore, pinworm eggs are not dependent on climate conditions. • Human hookworm and whipworm have never been reported in arctic or subarctic people. • Prehistoric infection with Hookworms, Trichuris and Strongyloides shows a North to South America distribution dated to 7000 years ago. • Because these worms are host-specific, they necessarily entered the New World through the migrations of human hosts. • Because the extracorporeal maturation of parasites requires warm conditions, migration routes through Beringia and into the center of North American continent were discounted. ESCMID• Transpacific migration or a Coastal migration, eLibrary was proposed. by author BC BC BC ESCMID eLibraryProf Araujo© by author PRESERVATION PALEOPARASITOLOGICAL REMAINS 4 • Conditions in the preservation of parasites vary from region to region. • Crucial for preservation is the rapid interruption of decay. • Limited to places of non moisture, high aridity, or frozen conditions. – combination of high and low temperatures, with dryness, result in rapid desiccation, hindering the activity of catalytic enzymes and destructive microorganisms (ie deserts). • Tropical climates are unsuitable for the preservation of organic matter. Combination of heavy rainfall, abundant insect life, and acid soil usually accelerate the process of ESCMIDdestruction of organic material. eLibrary by author ESCMID eLibrary by author Preservation of paleoparasitological remains PARASITES CHARACTERISTICS 4a • Paleoparasite evidence consists – mostly eggs, rarely of larvae, of intestinal parasites – chitinous shells of ectoparasites (lice,mites and flies) • Some parasites species produce protective structures that guard against decay. – Eggs of Ascaris, Capillaria, Trichuris, Oxiuros and Taenia have a good chance of recovery. • Thin walled eggs, Enterobious or Strongyloides preserve less well. • Problematic aspect of preservation: life cycle – Ancylostoma eggs hatch soon after deposition_ will not be found (not in latrine sediments, but in mummies and coprolites) – Strongyloides females lay eggs which hatch in intestine before ESCMIDdefecation__best condition_larvae willeLibrary be found by author Preservation of paleoparasitological remains: MICROENVIROMENTS COPROLITESPreservation of paleoparasitological DIAGNOSES remains 4b • Comes from Greek κπρος-kopros (feces) and λιφος-litos (rock). • It refer to hardened, stony feces. • Dehydrated by rapid loss of water , or mineralized, when the organic matter has better replaced and shaped by minerals. • Named by British Rev. William Buckland, geologist , paleontologist and “dinosaur hunter” in 19th cent. – ….coprolites, petrified feces found inside and outside fossil animals, often reveal to us not only the nature of the ingestion, displaying parts of other animals that were consumed, but even the nature of the mucosal surface of the gut and prove that the ingestion was done in those times more as less as in our times. (Wucherer, 1866) ESCMID eLibrary by author ESCMIDChame 2003. Mem InsteLibraryOswald Cruz 98 suppl 1. by author Recovery of parasites from coprolites Coprolite – Rehydration in 0,5 % Na3SO4 (72h) Addition drops of acetic formalin Flotation Sedimentacion ESCMID20 slides in all fields for eLibrarysample by author ESCMID eLibrary by author Preservation of paleoparasitological remains: MICROENVIROMENTS MUMMIFIEDPreservation of paleoparasitological BODIES remains4b • Mummy _ Well-preserved dead bodies. The majority found in dry places (sands of deserts or dry caves) where desiccation has taken place rapidly, doing naturally what Egyptians did by artifice. • The basic procedure is the same: water extracted rapidly from the tissues. • Low pH and anaerobic enviroment preserving organic remains. • References to mummification processes found in ancient documents as Genesis – Chap50 …And Joseph command his servants the physicians to embalm his father, so the physicians embalmed Israel, forty days were required for it, for so many are required for embalming… So Joseph died, being hundred and ten years old; and thet embalmed him, and he was put in a coffin in Egypt. • If rehydratation of coprolites in mummies does not occur with trisodium phosfate, ESCMID4% solution of KOH is