PALEOPARASITOLOGY OF HUMAN ACANTHOCEPHALAN INFECTION: A REVIEW AND NEW CASE FROM BONNEVILLE ESTATES ROCKSHELTER, NEVADA, U.S.A

This study reports a new case of acanthocephalan (thorny-headed worm) eggs in a coprolite from Bonneville Estates Rockshelter in eastern Nevada and uses archaeological and ethnographic data to better understand long-term relationships between people and acanthocephalans. Acanthocephalans are parasitic worms that use arthropods as intermediate hosts in their multi-host life cycles. Though acanthocephaliasis is rare among humans today, cases have increased in the last decade, and the discovery of acanthocephalan eggs in coprolites from archaeological sites in the Great Basin suggests a deep, shared history. At Bonneville Estates Rockshelter, 9 acanthocephalan eggs were recovered using a modified rehydration-homogenization-micro-sieving protocol on a coprolite that was radiocarbon dated to 6,040 ± 60 14C BP (7,160-6,730 cal BP), pushing back the oldest evidence of human acanthocephalan infection by 3 millennia. Researchers have proposed that the paleoepidemiology of acanthocephalans may relate to subsistence practices due to overlap in locations of infection and areas where insects are part of traditional foodways. This paper considers the paleoepidemiology of acanthocephalan infection through the first combined review of paleoparasitological, ethnographic, and archaeological records in western North America. Ethnographic and archaeological records support the hypothesis that archaeological cases of human acanthocephaliasis may be linked to entomophagy. Additional parasitological analyses are advised to determine whether this distribution is the result of dietary practices, host ecology, taphonomic issues, sampling biases, or a combination of factors.

Deciphering Diets and Lifestyles of Prehistoric Humans through Paleoparasitology: A Review

Parasites have affected and coevolved with humans and animals throughout history. Evidence of ancient parasitic infections, particularly, reside in archeological remains originating from different sources dating to various periods of times. The study of ancient parasites preserved in archaeological remains is known as paleoparasitology, and it initially intended to interpret migration, evolution, and dispersion patterns of ancient parasites, along with their hosts. Recently, paleoparasitology has been used to better understand dietary habits and lifestyles of ancient human societies. Paleoparasitology is increasingly being recognized as an interdisciplinary field within paleopathology that integrates areas such as palynology, archaeobotany, and zooarchaeology. Paleoparasitology also incorporates techniques such as microscopy, immunoassays, PCR, targeted sequencing, and more recently, high-throughput sequencing or shotgun metagenomics to understand ancient parasitic infections and thus interpret migration and evolution patterns, as well as dietary habits and lifestyles. The present review covers the original theories developed in the field of paleoparasitology, as well as the biology of some parasites identified in pre-Columbian cultures. Conclusions, as well as assumptions made during the discovery of the parasites in ancient samples, and how their identification may aid in better understanding part of human history, ancient diet, and lifestyles are discussed.

Integrative analysis of DNA, macroscopic remains and stable isotopes of dog coprolites to reconstruct community diet

Paleofeces or coprolites are often used to reconstruct diet at archaeological sites, usually using macroscopic analyses or targeted DNA amplification and sequencing. Here we present an integrative analysis of dog coprolites, combining macroscopic analyses, stable isotope measurements, and DNA shotgun sequencing to examine diet and health status. Dog coprolites used in this study were recovered from the Janey B. Goode and East Saint Louis archaeological sites, both of which are located in the American Bottom, an extensive Mississippi River floodplain in Southwestern Illinois. Based on the context of recovery, coprolites are assigned to the Late Woodland and Terminal Late Woodland periods (ca. 600-1050 AD). Given the scarcity of human remains from this time period, these dog coprolites can be useful as a proxy for understanding human diet during the Late Woodland period. We find that the Late Woodland dogs consumed a variety of fish as well as bird and plant taxa, possibly including maize, and also harbored intestinal parasites and pathogenic bacteria. By sequencing the fecal microbiome of the coprolites, we find some similarities to modern dog microbiomes, as well as specific taxa that can be used to discriminate between modern and ancient microbiomes, excluding soil contaminants. As dogs are often used as a surrogate to assess human diet, humans living with these dogs likely had a similar diet and were affected by similar parasites. These analyses, when integrated, show a more comprehensive view of ancient dog and human diet and health in the region during the initial expansion of maize agriculture than any individual method could alone.

Automontage microscopy and SEM: A combined approach for documenting ancient lice

Human ectoparasites, including lice, have been recovered from a wide range of archaeological materials. The human head louse, Pediculus humanus capitis, has been identified from mummies and sediments for decades. Louse eggs are the body part most commonly encountered and therefore the most frequently quantified. Typically, several types of microscopy are applied for egg documentation. For studies in which quantification of infestation is a goal, counting is done with the naked eye or with the aid of handheld lenses. For determination and stage classification, stereomicroscopy is commonly used. For more detailed examination of microstructure, light microscopy, scanning electron microscopy (SEM), and confocal laser scanning microscopy (CLSM) can be employed. In most reports, researchers use two or more techniques to accomplish interrelated goals. Automontage microscopy is used to document prehistoric arthropods with good success. Herein, we report the results of a combination of SEM and automontage microscopy to document lice and eggs recovered from South American mummies. This combined approach allows for simultaneous examination of internal and external characteristics. Thirty automontage composite images of 2 adult lice and 16 eggs showed that egg internal morphologies were easily examined showing the within-egg anatomy of emergent nymphs. SEM imaging of 9 lice and 129 eggs was completed. In the case of two adults and several eggs, SEM imaging was accomplish after automontage image capture of the same specimens. This one-to-one image comparison of SEM and automontage shows that transmitted light of automontage reveals egg internal structures and details of the adult lice. SEM allows for high magnification examination of egg, nymph and adult microstructures. We conclude that automontage imaging followed by SEM results in efficient graphic documentation of rare louse specimens.

Recovering parasites from mummies and coprolites: an epidemiological approach

In the field of archaeological parasitology, researchers have long documented the distribution of parasites in archaeological time and space through the analysis of coprolites and human remains. This area of research defined the origin and migration of parasites through presence/absence studies. By the end of the 20th century, the field of pathoecology had emerged as researchers developed an interest in the ancient ecology of parasite transmission. Supporting studies were conducted to establish the relationships between parasites and humans, including cultural, subsistence, and ecological reconstructions. Parasite prevalence data were collected to infer the impact of parasitism on human health. In the last few decades, a paleoepidemiological approach has emerged with a focus on applying statistical techniques for quantification. The application of egg per gram (EPG) quantification methods provide data about parasites' prevalence in ancient populations and also identify the pathological potential that parasitism presented in different time periods and geographic places. Herein, we compare the methods used in several laboratories for reporting parasite prevalence and EPG quantification. We present newer quantification methods to explore patterns of parasite overdispersion among ancient people. These new methods will be able to produce more realistic measures of parasite infections among people of the past. These measures allow researchers to compare epidemiological patterns in both ancient and modern populations.

Reestablishing rigor in archaeological parasitology

Archaeological parasitology originated in the mid-twentieth century with interdisciplinary teams of specialists directed by archaeologists. The goals of such studies were detailed analyses of dietary, medicinal, and environmental factors that shaped the patterns of infection. By the 1970s, a cadre of unique coprolite analysts was trained to analyze macroscopic and microscopic remains for integrated reconstructions of the cultural determinants of parasitism. During these first phases of research, diagnostic rigor was maintained by direct training of specialists in parasitology and archaeology sub-disciplines including archaeobotany and archaeopalynology. Near the end of the twentieth century, however, "paleoparasitology" was defined as a separate field focusing on defining parasite distribution through time and space. Ironically, this focus resulted in an increase in misdiagnosis, especially prominent after 2000. Paleoparasitology does not explicitly include other specialized studies in it research design. Thus, dietary, environmental and medicinal inferences have been neglected or lost as samples were destroyed solely for the purpose of parasitological analysis. Without ancillary archaeological studies, paleoparasitology runs the risk of separation from archaeological context, thereby reducing its value to the archaeologists who recover samples for analysis.

Temporal and Spatial Distribution of Enterobius vermicularis (Nematoda: Oxyuridae) in the Prehistoric Americas

Investigations of Enterobius sp. infection in prehistory have produced a body of data that can be used to evaluate the geographic distribution of infection through time in the Americas. Regional variations in prevalence are evident. In North America, 119 pinworm positive samples were found in 1,112 samples from 28 sites with a prevalence of 10.7%. Almost all of the positive samples came from agricultural sites. From Brazil, 0 pinworm positive samples were found in 325 samples from 7 sites. For the Andes region, 22 pinworm positive samples were found in 411 samples from 26 sites for a prevalence of 5.3%. Detailed analyses of these data defined several trends. First, preagricultural sites less frequently show evidence of infection compared to agricultural populations. This is especially clear in the data from North America, but is also evident in the data from South America. Second, there is an apparent relationship between the commonality of pinworms in coprolites and the manner of constructing villages. These analyses show that ancient parasitism has substantial value in documenting the range of human behaviors that influence parasitic infections.

Human Coprolites as a Source for Paleomicrobiology

The paleomicrobiology of coprolites, which are fossilized fecal materials, has already yielded data about various organisms, including micro-eukaryotes, bacteria, and archaea, thus expanding our comprehension of ancient human dietary habits, gut microbiota, and intestinal and systemic infections. This mini-review briefly describes previous works and summarizes the main techniques used in handling coprolites and the findings obtained about ancient gut microbiota. Past intestinal and systemic infections are outlined.

Palaeoparasitology - Human Parasites in Ancient Material

Parasite finds in ancient material launched a new field of science: palaeoparasitology. Ever since the pioneering studies, parasites were identified in archaeological and palaeontological remains, some preserved for millions of years by fossilization. However, the palaeoparasitological record consists mainly of parasites found specifically in human archaeological material, preserved in ancient occupation sites, from prehistory until closer to 2015. The results include some helminth intestinal parasites still commonly found in 2015, such as Ascaris lumbricoides, Trichuris trichiura and hookworms, besides others such as Amoebidae and Giardia intestinalis, as well as viruses, bacteria, fungi and arthropods. These parasites as a whole provide important data on health, diet, climate and living conditions among ancient populations. This chapter describes the principal findings and their importance for knowledge on the origin and dispersal of infectious diseases.

Lutz's spontaneous sedimentation technique and the paleoparasitological analysis of sambaqui (shell mound) sediments

Parasite findings in sambaquis (shell mounds) are scarce. Although the 121 shell mound samples were previously analysed in our laboratory, we only recently obtained the first positive results. In the sambaqui of Guapi, Rio de Janeiro, Brazil, paleoparasitological analysis was performed on sediment samples collected from various archaeological layers, including the superficial layer as a control. Eggs of Acanthocephala, Ascaridoidea and Heterakoidea were found in the archaeological layers. We applied various techniques and concluded that Lutz's spontaneous sedimentation technique is effective for concentrating parasite eggs in sambaqui soil for microscopic analysis.