Studies on protozoa in ancient remains - A Review

Abstract

Since the beginning of the last century, paleoparasitology has been focused on understanding the origin and evolution of infectious diseases, relying on archaeological and paleontological material to do so. A wide diversity of intestinal parasites has been retrieved from ancient remains, primarily from helminths (Gonçalves et al. 2003). However, although protozoa exhibit a global distribution, they are not recovered easily from archaeological contexts. This scarcity might be related to difficulties in detecting these organisms using traditional optical microscopy and to the sensitivity of parasitic structures, which are less resistant to taphonomic processes, leading to a low estimation of protozoa in the archaeological record.This literature review aims to identify and summarise the geographic distribution of protozoa in the archaeological record, with an emphasis on protozoa associated with humans, including both intestinal and tissue parasites and the methodologies used to study them in ancient remains. An electronic database search was performed targeting studies on protozoa in the fields of paleoparasitology, archaeology and paleopathology and authors showing previous research efforts on this subject. The search comprised all publications found on this topic in PubMed and ScienceDirect and their bibliographies were screened as well. The data extracted from the literature included parasite species, archaeological sites and dates, the methods applied and the results of the studies. There were no exclusions related to publication dates or languages. Methodological approaches to the identification of protozoaAlthough macroscopic examinations of lesions are generally limited to making observations of body preservation and the presence of specific landmarks, this technique is the most direct way of approaching disease in archaeological remains. For example, Chagas disease was diagnosed based on an altered large intestinal tract in a pre-Columbian mummy and later confirmed via molecular biological methods (Dittmar et al. 2003). However, this finding was exceptional, as the majority of infectious diseases will not be detected using such methodology. Consulting historical documents provides an indirect method for approximating protozoan infections. By reviewing medical documents, autopsy reports and original death certificates recorded by court physicians, Gino Fornaciari et al. (2010a, b) reconstructed the medical history of one of the most influential families of the Italian Renaissance, the Medici (Nerlich et al. 2012).In a similar manner, the origin of leishmaniasis in the Americas was discussed based on ethno-historical documents and anthropomorphic representations on Mochica ceramics (huacos) showing lesions similar to those found in mucous leishmaniasis (Altamirano-Enciso et al. 2003).Microscopy has been the traditional method for parasite identification in paleoparasitological analyses and the first protozoa found in fossilised faeces (coprolites) were described using this technique (Pizzi & Schenone 1954...

The Evolutionary History of Plasmodium vivax as Inferred from Mitochondrial Genomes: Parasite Genetic Diversity in the Americas

“…Unfortunately, the loss of the putative source populations makes it difficult to rigorously test this model, although the recovery of ancient DNA from a European sample of P. vivax could be used to this end. However, while ancient DNA has been recovered from P. falciparum samples (Taylor et al 1997; Sallares and Gomzi 2001; Frías et al 2013), we are unaware of any similar successes involving P. vivax .…”

Disease: A Hitherto Unexplored Constraint on the Spread of Dogs (Canis lupus familiaris) in Pre-Columbian South America

“…(Cantacessi et al 2015;Dantas-Torres and Otranto 2014). Some must have infected people in pre-Columbian times based on osteological (Enciso et al 2001), immunological (Frías et al 2013), and other palaeopathological data (Costa Junqueira et al 2009;Marsteller et al 2011), the recovery of ceramics showing human faces disfigured by what looks like mucocutaneous leishmaniasis (which is restricted to Latin America), and sixteenth-century Spanish descriptions of the disease, though comparable evidence of the almost always fatal visceral form is understandably lacking (Lainson 2012). As well as L. infantum, two native species, in particular, 'deserve greater attention' with regard to canine leishmaniasis (Dantas-Torres 2009, p. 6).…”

Human Parasites in Medieval Europe

“…This can make it challenging to identify them with microscopy after thousands of years exposed to the elements. For example, the fragile intestinal protozoa Entamoeba histolytica and Giardia duodenalis are rarely seen in archaeological sediments when using microscopy, but are more easily detected using enzyme-linked immunosorbent assay (ELISA) (Gonçalves et al, 2004;Frías et al, 2013;Le Bailly and Bouchet, 2015). The eggs of some species of helminths with fragile walls, such as pinworm (Enteriobius vermicularis) and hookworm (Ankylostoma duodenale/Necator americanus), have been found in many sites in the Americas where desiccated coprolites have survived (Ara ujo et al, , 2011, but have been extremely rare in Europe and Asia where most faecal samples come from waterlogged cesspools and mineralized coprolites.…”