New Evidence for the Antiquity of the Intestinal Parasite Trichuris (Whipworm) in Europe

Article excerpt

Introduction

The whipworm, Trichuris trichiura L., is one of the most common human intestinal parasites worldwide. The adult nematode worm inhabits the large intestine and eggs are passed in the faeces of the host. The eggs then embryonate in the environment and are ingested by a new host via contaminated food or water. Despite its prevalence, little is known of the origins and global spread of this nematode because, in common with other endoparasites, specific historical records of its occurrence are few and, in any case, much later in date than its presumed origin.

Archaeological evidence for the presence of Trichuris in Europe occurs in the form of its eggs in coprolites, cess and occupation deposits from a variety of sites, such as the Bronze Age settlement of Brean Down, England (Jones 1990), Iron Age salt mines at Hallstatt and Hallein in Austria (Aspock et al. 1974), the Roman-period forts of Bearsden in Scotland (Knights et al. 1983) and Carlisle in England (Jones & Hutchinson 1991), and from urban contexts such as late Saxon London (de Rouffignac 1991), Viking Age and medieval York (Jones 1983, 1985), and medieval Winchester (Taylor 1955, Pike & Biddle 1966). Other records have come from preserved human remains such as the Danish Iron Age 'bog bodies', Grauballe Man and Tollund Man (Helbaek 1958), and Lindow Man in England (Jones 1986). The oldest European discoveries associated with a human body are from the intestine of the Neolithic (c. 3200-3300 cal BC) 'iceman' from the Otztal Alps (Aspock et al. 1996, 2000), similar in date to the eggs found in human coprolites from Chalain, a Neolithic site in France (Bouchet et al. 1995).

Possibly the oldest New World records of eggs identified as those of Trichuris trichiura are from coprolites and a naturally mummified human body from a cave in Brazil, dated to between 3490 [+ or -] 120 BP and 430 [+ or -] 70 BP and associated with evidence for agricultural activity (Ferreira et al. 1980, 1983). Horne (1985) and Reinhard et al. (1987) provide reviews of New World records of Trichuris and other endoparasites.

These discoveries suggest that whipworm infections may have been prevalent among later prehistoric human populations, and probably became increasingly so in the crowded conditions of towns. The question remains, however, of how and at what date humans first acquired these parasites. Were they originally present in early humans, or were they acquired from wild or domesticated animals, perhaps associated with the increasingly close animal contact involved in pastoral farming? It has, for example, been argued that Trichuris and Ascaris (which are commonly found together in archaeological human remains) passed to humans from domestic pigs (Kliks 1990). Did acquisition of the parasite occur as a single event during the global spread of humans or several times and by different routes in different parts of the world (see discussion by Kliks 1990)?

The association of Trichuris with the prehistoric 'iceman' indicated that whipworm was present in western Europe in the early Neolithic period, after the adoption of agriculture. Here I report the discovery of Trichuris eggs in late Mesolithic deposits from south Wales, which pushes the presence of the genus in Europe back over 2000 years, and into a presumed pre-agricultural context. This suggests that the origins of farming and human acquisition of this particular parasite need not be connected.

The site

The discovery comes from late Mesolithic intertidal peat deposits from the Gwent Levels at Goldcliff in south Wales, on the northern side of the Severn Estuary. These deposits are currently being examined as part of a project to investigate Mesolithic-Neolithic coastal environmental change and human activity using a range of techniques, including analysis of biological remains and animal and human footprints preserved in the intertidal peat and estuarine silts, as well as the excavation of later Mesolithic flint and bone scatters (Bell et al. …