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Only a few surveys have ever been carried out of the helminths of the commensal rodents found in the traditional wet markets that play such an important part of daily life in South-east Asia. The potential of rodents as reservoirs of zoonoses including helminths is of great interest since in these markets humans and rodents come into closer contact than in other environments and food may be indirectly contaminated via rodent faeces. Helminths in a total of 98 rats belonging to two species (Rattus norvegicus and Rattus exulans) were surveyed in eight traditional wet markets in Udon Thani, Thailand. Thirteen species of helminths were recovered, seven of which are potentially zoo-notic, with an overall prevalence of 89.8 %. Our results show that rodents in wet markets could pose a threat to human health as potential reservoirs of zoonotic helminthiases.

Onchocerca eberhardi n. sp. from the sika deer, Cervus nippon, in Japan is described. Adult worms lived in the carpal ligament; infection reached high levels (up to 25 female and 16 male worms in a single carpal limb). Skin dwelling microfilariae were mainly found in the ears. Prevalence of infection was 81 % at the type locality, Mt. Sobo, in Kyushu. The new material was compared to the 31 species of Onchocerca presently known. Onchocerca eberhardi n. sp. females were characterized by a long slender anterior end and a thin esophagus ≤ 1 mm long with no or only a slight glandular region. The vulva was located near the level of the mid-esophagus and the cuticle had transverse external ridges and internal striae (two striae between adjoining ridges). The most similar species were O. stilesi (re-examined), O. lienalis, and to a lesser extent O. gutturosa, all from bovids (cattle). Two main lineages of Onchocerca are recognized in cervids with either primitive or with derived characteristics (as exemplified by the new species). The species in both lineages are not restricted to cervids but are also found in bovids in the Holarctic region, suggesting that the species diversified in the two host groups simultaneously, when these host groups lived in the same geographic area.

A new onchocercid species, Loxodontofilaria caprini n. sp. (Filarioidea: Nematoda), found in subcutaneous tissues of 37 (33%) of 112 serows (Naemorhedus crispus) examined in Japan, is described. The female worm had the characteristics of Loxodontofilaria, e.g., the large body size, well-developed esophagus with a shallow buccal cavity, and the long tail with three caudal lappets. The male worm of the new species, which was first described in the genus, had unequal length of spicules, 10 pairs of pre- and post-caudal papillae, and three terminal caudal lappets. Deirids were present in both sexes. Among four species of the genus Loxodontofilaria: one from the hippopotamus and three from the Elepantidae, L. caprini n. sp. appears close to L. asiatica Bain, Baker & Chabaud, 1982, a subcutaneous parasite of Elephas indicus in Myanmar (Burma). However, L. caprini n. sp. is distinct from L. asiatica in that the Japanese female worm has an esophagus half as long and the microfilariae also half as long with a coiled posterior. The microfilariae were found in the skin of serows. The new parasite appears to clearly illustrate a major event in the evolution of onchocercids: the host-switching. This might have occurred on the Eurasian continent, where elephantids and the lineage of rupicaprines diversified during the Pliocene-Pleistocene, or in Japan, into which some of these hosts migrated.