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The genus Eustrongylides includes nematodes known as the etiological agent of the "big red worm disease." The aim of this work was to identify Eustrongylides spp. larvae from fish and adults from great cormorant ( Phalacrocorax carbo ) sampled at Lake Trasimeno, Italy, by morphological and molecular analysis. Histopathological description of the lesions in birds was also provided. We described adults of Eustrongylides excisus for the first time in Italy, and we also linked larval stages 3 and 4 to adults. The use of molecular tools combined with the traditional taxonomy will help the identification of the species, including species inquirendae. Moreover, molecular analysis can also help to investigate the role of intermediate and paratenic hosts, to deepen the knowledge about geographical distribution of the different Eustrongylides spp. and to define the zoonotic potential of E. excisus , which has not yet been identified as causal agent of human cases.

The spleen is an important organ of vertebrates. Splenic mass can change in response to a variety of factors. We tested whether splenic mass of masked shrews, Sorex cinereus, was related to sex, age, time of the year, or intensity of bladder nematode (Liniscus [=Capillaria] maseri) infection, after controlling for host body mass. For females, body mass was a strong predictor of splenic mass. For males, splenic masses were greater later in the year and in more heavily infected males. The latter appeared to represent a threshold response wherein only the most heavily infected individuals had enlarged spleens.

A female dioctophymatid nematode larva, presumably belonging to the genus Dioctophyme, was found in a dermal granuloma accompanied by creeping eruption in the left inner thigh of a 26-yr-old Chinese woman who had stayed in Japan for 4 yr. Morphology of the sectioned worm is described in detail. This is the fourth case of dermal infection with dioctophymatid larva in humans.

Negative effects due to infection have not been documented for most natural host-parasite associations. I performed an infection experiment to measure the physiological consequences of infection by Capillaria hepatica in deer mice (Peromyscus maniculatus gracilis). Compared to their uninfected siblings, infected mice displayed increased serum concentrations of alkaline phosphatase and total proteins and reduced concentrations of albumin. Infected mice also had higher hematocrits and enlarged livers and spleens. There was no difference in swimming endurance between infected and control animals, possibly because mice did not perform at maximum aerobic capacity. Sex differences in alkaline phosphatase and albumin levels suggest that females are more sensitive to similar burdens of C. hepatica. Different hematocrit responses between mice from 2 localities suggest that historical associations can lead to evolutionary change in pathophysiology caused by this nematode. Further experiments would reveal whether these disturbances lead to reductions in host fitness.

A 7-yr retrospective survey (1986-1993) of 193 raccoons (Procyon lotor) from 4 different geographic locations (South Carolina, Virginia, and 2 sites in Pennsylvania) in the eastern United States was conducted by histopathological examination of various tissues. Lesions indicative of capillariasis were observed in raccoons at all locations. An overall prevalence of 45% was recorded. Highest prevalence of nematodes in tissues (71%) was seen in the rural Pennsylvania site. Nematodes were confined to the mucosa of the anterior alimentary tract (mouth, tongue, esophagus) or urinary system (bladder, urethra) without significant inflammation except for a single raccoon in which Capillaria sp. were present in the tracheal mucosa and within the subjacent lamina propria, with moderate inflammatory cellular infiltrate.