Cameronia laplatae n. sp. found in City Bell, Argentina, parasitizing crickets is described and illustrated. The new species is distinguished from other members of the genus Cameronia by the distribution pattern of the genital papillae in the male. It differs from all congeners mainly in having two pairs preanal y two pairs postanal papillae.

Xiphidiocercariae, aquatic larval stages of some trematodes are considered a potential instrument for biological control of mosquitoes. In this study we evaluated its natural occurrence in Campinas region and two places in Vale do Ribeira (Registro and Miracatu), São Paulo State. Snails were obtained from fresh water collections from September 1996 to February 1999. The species collected were Lymnaea columella, Physa marmorata, Biomphalaria tenagophila, Biomphalaria sp., Drepanotrema cimex, D. lucidum and Drepanotrema sp. Fasciola hepatica, xiphidiocercariae (Haematoloechidae) and echinostomatid cercariae were detected in the lymnaeids snails from Miracatu, SP. In the same locality were found planorbids snails parasitized by furcocercariae, echinostomatid cercariae and xiphidiocercariae. The xiphidiocercariae found in the planorbids were different from those obtained from lymnaeids. One Biomphalaria sp. infected with furcocercariae was found in Louveira, SP. In the ROSA place (Campinas, SP) an individual of Biomphalaria sp. and one of L. columella were found infected by the furcocercariae and echinostomatid cercariae, respectively. In the place UNI-I, in Campinas, one L. columella was infected by furcocercariae. Double infection in snails from Miracatu was also observed.

We studied the parasite fauna and food contents of 38 juvenile of Notothenia c.f. angustata specimens captured in the intertidal of Island Santa María and Maule, in the Arauco Gulf, Chile. Trophic habits of Notothenia c.f. angustata were not different between localities, which was mainly algae. A total 11 parasitic taxa among were found with the digenean Lecitasther macrocotyle, cestode larvae Tetraphyllidea and Diphyllidea and nematode Ascarophis sp. being the dominant taxa. The abundance of parasites was similar in the two localities, although the infracommunity richness was higher in fish from Maule. The most abundant parasite was L. macrocotyle in hosts from Isla Santa María, while those from Maule they were the Diphyllidea larvae and nematodes Ascarophis sp. The body length of the hosts was not a good predictor of the variations in abundance and richness at infracommunities, probably because of the early ontogenetic stage of fishes.

In this communication is presented the finding of the tapeworm Diphyllobothrium pacificum, parasite of sea lions, in Canis familiaris (dog) in Chincha city, Peru. This is the first canine infection with D. pacificum in the South Peruvian coast.

The effect of El Niño/ENSO on terrestrial atmosphere appears to be extremely clear. However there are outstanding evidences showing its effect on humans and their activities. In fact, prevalence of some parasitic infections have increased during El Niño phenomenon. The reasons for that are the migrations of sylvatic mammals, fishes and birds as well as by environmental contamination. In this report, we show evidence respect of new cases of human infection by Diphyllobothrium pacificum clearly associated with a cyclic manifestation of El Niño in the Chilean Pacific coast during 1975-2000.

We present the case of a four-year-old boy with a history of repeated upper respiratory tract infections and pyoderma. He presented fever, seizures, inability to talk, loss of swallowing, fine tremor in the upper extremities; positive bilateral Babinski reflex and quadriparesis. The diagnosis of Bruton's disease and generalized microporidiosis was based on immunologic analysis, smear tests with chromotrope R2 stain and indirect immunofluorescense with monoclonal 3B6 antibody for Encephalitozoon species in samples of spinal fluid, bronchial and paranasal sinus aspirates and stool, which were all positive. The patient was treated with albendazol during 72 days; he left the hospital in a good condition, walking, talking and able to swallow. His laboratory test controls were negative; he is followed up in the outpatient department.

Hydatidosis is and endemic disease in the south of Chile, especially in Region IX where remain rates of high prevalence. Cholangiohydatidosis is an infrequent complication of liver hydatidosis. The objective of this paper is to describe clinical features of a series of patients with cholangiohydatidosis. Series of cases of cholangiohydatidosis treated consecutively and the corresponding follow-up is reported. Clinical, laboratory and images characteristics are described. Descriptive statistic was used its incidence was calculated. In the studied period, 13 patients with cholangiohydatidosis were recruited, 9 men (69.2%) and 4 women (30.7%). Observed laboratory abnormalities were an increment of leukocytes in 8 patients (61.5%) and hepatic cholestasis with hepatocyte signs of cytolysis in 11 patients (84.6%). Choledocus diameter average measured by ultrasonography was 24.7 mm. All the patients had at least one liver cyst whose diameter average was of 12.1 cm. At surgery, evidence of biliary communications was detected in all patients and biliary decompression was carried out through a choledocostomy in 12 patients (92.3%) and by choledocoduodenal anastomoses in one case (7.7%). With a mean follow-up of 38.7 months morbility was 23% and mortality 7.7%. Accumulated incidence of this entity was of 0.07 cases in 5 years. Cholangiohydatidosis is an uncommon complication of liver hydatidosis that presents considerable morbidity and mortality rates.

Here, it has been described that normal fresh sera from rainbow trout (Oncorhynchus mykiss) were able to lyse Tylodelphys sp. metacercariae isolated from Galaxias maculatus (Jenyns, 1842) (Teleostei, Galaxiidae) brain. This effect was time dependent, and progressively increased since 1 h up to 18 h incubation. There were oscillations in the ability of different sera samples to lyse these parasites. Similar values were achieved with other salmonid sera, and also with normal human sera pool. The lytic activity was abolished by heat-inactivated sera, by zymosan treatment and by incubation in the presence of EDTA. However, the mean values obtained in the presence of EGTA-Mg++ did not significantly differ from those found with sera as a source of complement. The results of this study suggested the role of complement alternative pathway on Tylodephys sp. in vitro lysis, under our experimental conditions.

The presence of the nematode Spinitectus jamundensis in cardial and pyloric regions of the stomach of Prochilodus lineatus is observed. Samples of the parasitized stomach were analyzed by histological techniques using Hematoxilin-Eosin and Mallory (Azan) Heidenhain's stainnigs. The macroscopical description of the inner surface of the stomach showing damages in the parasites penetration sites, were observed. Histological observations show that the parasite enters the mucous membrane reaching muscular mucous membrane of the cardial region or the epithelial plaits in the pyloric region reaching up to the muscular layer without crossing it. In this way, the parasite remains confined by a thin layer of connective tissue and in almost direct contact with tissue liquids. Sometimes, in host tissues as response to the parasite presence, an increased level in the amount of lymphocytes in the surrounding tissues is observed.

Between may and july 1994, 17 adult returning salmons, Oncorhynchus kisutch, were collected in the River Simpson, Chile. All fishes showed infection by plerocercoids of Diphyllobothrium sp. in different locations: stomach, spleen, liver, mesenteries and gonads. Infection with larval cestodes of an unidentified species of Phillobothriidae was determined in the intestine of seven (41.2%) salmons and its prevalences of infection showed significant differences between female and male salmons. The 94.4% of total plerocercoids of Diphyllobothrium were isolated from the stomach wall. Prevalence and mean intensity of infection by Diphyllobothrium sp. did not show significant differences between fishes of different sex.