HEAD LOUSE PALEOEPIDEMIOLOGY IN THE OSMORE RIVER VALLEY, SOUTHERN PERU.

Recent studies of louse ectoparasites from mummies have developed robust data sets that allow a true epidemiological approach to the prehistory of louse parasitism. One epidemiological principle is that the binomial of overdispersion is normally negative, meaning that in a host population, parasites are aggregated in a few individuals. We demonstrate the overdispersion of lice in 3 different prehistoric communities that differ along 3 axes or variables: environmental setting, socioeconomic status, and cultural affiliation. Distinct cultural practices could have been involved in different patterns of louse infestation. Prevalence, intensity, and abundance of infestations exhibit statistically significant differences between the communities. We also find differences in prevalence between subadults and adults that contrasted by cultural affiliation and suggest conditions different from those seen today. We show that overall prevalence was affected primarily by ecological setting, not socioeconomic status nor cultural affiliation. These findings demonstrate that statistical analysis of archaeological data can reveal the states of infestation in past populations with lifestyles not seen in modern people. Our approach paves the way for future comparisons of subpopulations within archaeological communities.

Back to basics: Could simple experiments resolve important parasitology enigmas? The rarity of Ascaris eggs compared with Trichuris eggs in archeology and other contexts.

Most parasitologists face a conundrum throughout their careers: 'which parasite eggs are more resistant to environmental stress, Ascaris spp. or Trichuris spp.?' In this analysis, our experimental and statistical analyses demonstrated that Trichuris sp. is more resistant than Ascaris sp. We highlight that desiccation exerts a major effect on the conservation of Ascaris eggs, and this may result in an underestimation of Ascaris eggs in paleoparasitological records. This observation can be extrapolated to more modern scenarios, for example, parasitological research in animal feces from semiarid environments, where whipworms are more common than roundworms. Similarly, this could be a plausible explanation for the higher frequency and abundance of whipworms than roundworms, when other hypotheses are unsupported.

REVIEW OF PARASITES FOUND IN EXTINCT ANIMALS: WHAT CAN BE REVEALED.

Parasitism is inherent to life and observed in all species. Extinct animals have been studied to understand what they looked like, where and how they lived, what they fed on, and the reasons they became extinct. Paleoparasitology helps to clarify these questions based on the study of the parasites and microorganisms that infected those animals, using as a source material coprolites, fossils in rock, tissue, bone, mummy, and amber, analyses of ancient DNA, immunodiagnosis, and microscopy.

Methodological innovations for the study of irreplaceable samples reveal giardiasis in extinct animals (Nothrotherium maquinense and Palaeolama maior).

The use of diagnostic methods that prevent irreplaceable samples (from museum collections, archaeological and paleontological samples) of being consumed or that increase their yield is relevant. For museum collections, archaeological and paleontological samples it is essential to conserve samples, subsamples or portions for future research. We are addressing methods for conservation of irreplaceable samples that could be fully consumed. Innovations in methodologies that are used in studies of Paleoparasitology and Paleomicrobiology will contribute to the preservation of collections. Therefore, to the development of archaeology and paleontology in the future, we evaluated whether the discarded material of the immunochromatography test could be used for molecular diagnosis and vice versa. We used a genotyped experimental coprolite positive for Giardia duodenalis. The diagnosis was positive for giardiasis in both cases. This methodology can be corroborated with the coprolite of a Paleolama maior (extinct llama) previously diagnosed for G. duodenalis with an immunoenzymatic test. The residue of the pre-digestion step of the DNA extraction before adding Proteinase K was confirmed positive with the immunochromatographic test. Also, the DNA extraction residue from a coprolite of Nothrotherium maquinense (ground sloth) was tested positive with immunochromatographic test for G. duodenalis. These are the oldest findings for G. duodenalis confirming that this intestinal parasite occurred among Northeastern Brazilian Megafauna animals from the late Pleistocene period, correlated to human occupation. The relevance of these results will allow the study by different methodological approaches from a small amount of material, reusing discarded materials.

Study of infectious diseases in archaeological bone material - A dataset.

Bones of human and ground sloth remains were analyzed for presence of Trypanosoma cruzi by conventional PCR using primers TC, TC1 and TC2. Sequence results amplified a fragment with the same product size as the primers (300 and 350pb). Amplified PCR product was sequenced and analyzed on GenBank, using Blast. Although these sequences did not match with these parasites they showed high amplification with species of bacteria. This article presents the methodology used and the alignment of the sequences. The display of this dataset will allow further analysis of our results and discussion presented in the manuscript "Finding the unexpected: a critical view on molecular diagnosis of infectious diseases in archaeological samples" (Pucu et al. 2017) [1].

Paleoparasitology: the origin of human parasites.

Parasitism is composed by three subsystems: the parasite, the host, and the environment. There are no organisms that cannot be parasitized. The relationship between a parasite and its host species most of the time do not result in damage or disease to the host. However, in a parasitic disease the presence of a given parasite is always necessary, at least in a given moment of the infection. Some parasite species that infect humans were inherited from pre-hominids, and were shared with other phylogenetically close host species, but other parasite species were acquired from the environment as humans evolved. Human migration spread inherited parasites throughout the globe. To recover and trace the origin and evolution of infectious diseases, paleoparasitology was created. Paleoparasitology is the study of parasites in ancient material, which provided new information on the evolution, paleoepidemiology, ecology and phylogenetics of infectious diseases.

Paleoparasitology: the origin of human parasites / Paleoparasitologia: a origem dos parasitas humanos

Parasitism is composed by three subsystems: the parasite, the host, and the environment. There are no organisms that cannot be parasitized. The relationship between a parasite and its host species most of the time do not result in damage or disease to the host. However, in a parasitic disease the presence of a given parasite is always necessary, at least in a given moment of the infection. Some parasite species that infect humans were inherited from pre-hominids, and were shared with other phylogenetically close host species, but other parasite species were acquired from the environment as humans evolved. Human migration spread inherited parasites throughout the globe. To recover and trace the origin and evolution of infectious diseases, paleoparasitology was created. Paleoparasitology is the study of parasites in ancient material, which provided new information on the evolution, paleoepidemiology, ecology and phylogenetics of infectious diseases.

O parasitismo é composto por três subsistemas: o parasito, o hospedeiro e meio ambiente. Não existe organismo que não possa ser parasitado. A relação entre um parasito e suas espécies de hospedeiro não resulta, na maior parte das vezes, em dano ou doença ao hospedeiro. Entretanto, numa doença parasitária, a presença de um determinado parasito é sempre necessária, pelo menos em um determinado momento da infecção. Algumas espécies de parasitos que infectam humanos foram herdados dos pré-hominídeos, e foram compartilhados com outras espécies de hospedeiro filogeneticamente próximas, mas outras espécies foram adquiridas pelo meio ambiente à medida que os humanos se desenvolveram. As migrações humanas espalharam os parasitos adquiridos por todo o mundo. Para recuperar e traçar a origem e evolução das doenças infecciosas foi criada a paleoparasitologia. Paleoparasitologia é o estudo dos parasitos em materiais antigos, que trouxe novas informações na evolução, paleoepidemiologia, ecologia e filogenética das doenças infecciosas.