Human pentastomiasis in China: case report and literature review.

A 13-yr-old boy was admitted because of persistent fever, abdominal pain and diarrhea for 3 mo. Abdomen CT revealed hepatomegaly and multiple nodular low-density pathological changes. At laparotomy considerable yellow and turbid ascites were seen in the abdominal cavity and miliary nodules were noted on the surface of the omentum majus, liver, and small intestine wall. Histological examination revealed parenchymal tubercles containing several worms. Pathological diagnosis was parasitic granuloma. These parasites were identified as Porocephalus taiwana sp.nov. The patient made an uneventful recovery after therapy and was discharged. Moreover, another 17 cases of human pentastomiasis reported from China were reviewed. Human pentastomiasis is an extremely rare disease and this is only the second case of human Porocephalus taiwana sp.nov infection. Pentastomiasis should be considered in differential diagnosis of patients with a history of abdominal symptoms and eating of poorly-cooked snakes.

Patterns of asexual reproduction in the fissiparous seastar Coscinasterias acutispina (Asteroidea: Echinodermata) in Japan.

The morphological and anatomical characteristics of the fissiparous seastar Coscinasterias acutispina were investigated at 23 sites around Japan in order to clarify the environmental factors determining asexual reproduction. The frequency of recent fission among the sites differed, although no significant differences were evident among the three major sea areas around Japan (the Sea of Japan, Seto Inland Sea, and Pacific Ocean), indicating that the spatial variability in incidence of fission might be determined on a local scale. Morphological observations revealed that the seastars endoparasitized by Dendrogaster okadai had not undergone fission recently, suggesting that fission was suppressed by parasitism. Stepwise multiple regression analysis of the frequency of seastars that had recently undergone fission revealed that nutrient conditions affected the incidence of fission. The relationships between the pyloric caeca index and arm length ratio at the individual level suggested that good nutritional conditions were required before the occurrence of fission. Additionally, regression analysis showed that high temperature was one of the triggers of fission in C. acutispina. Thus, the process of asexual reproduction in C. acutispina appears to be governed by intricate interactions among several factors, including parasitism by D. okadai, nutrient conditions, and high temperature.

Influence of salinity on prevalence of the parasite Loxothylacus panopaei in the xanthid Panopeus obesus in SW Florida.

This study was conducted to examine the potential influence of salinity, a proxy for freshwater inflow, on the prevalence of the castrator parasite Loxothylacus panopaei on saltmarsh mud crabs Panopeus obesus on SW Florida oyster reefs. Spatial and seasonal patterns of the presence of potential host crabs and the prevalence of the parasite were assessed in the Caloosahatchee, Estero, and Faka Union estuaries. Lift nets (1 m2) containing 5 1 of oyster clusters were deployed on intertidal reefs at 3 sites along the salinity gradient of each estuary. Nets were deployed during 3 seasonally dry and 3 seasonally wet months for a period of 30 d. P. obesus densities tended to increase downstream in higher salinity waters, with crabs being absent from the upper station in the Caloosahatchee during both seasons and absent from the upper station of the Faka Union during wet months. Parasite prevalence was reduced upstream in each estuary during wet months compared to dry months, and for those estuaries that experienced higher relative levels of freshwater inflow. Furthermore, parasite prevalence was positively correlated with the mean salinity of capture of host crabs. Based on the distribution of P. obesus and the above patterns related to salinity, it appears that freshwater inflow and seasonal rains might regulate the prevalence of this parasite in SW Florida by creating spatiotemporal, low salinity refuges for its host.

Effects of the Briarosaccus callosus infestation on the commercial golden king crab Lithodes aequispina.

Commercial crab populations off the Kamchatka coasts are infested to a considerable degree by the rhizocephalan parasite Briarosaccus callosus: of 769 Lithodes aequispina males examined, 43 (5.7%) were parasitized. Infestations result in the feminization of the crabs, a significant decrease in the cheliped length, and a significant decrease in the carapace length and width. We suggest that commercial selection of healthy males, and the returning of unsuitable crabs, including infested ones, back into the sea, results in an increase of the proportion of infested crabs in the population, their elimination from reproduction, and, eventually, the gradual degradation of a whole population. To minimize as far as possible the negative effects of commercial crab harvesting, all infested crab specimens caught must be destroyed, either aboard or elsewhere, instead of throwing them back into the sea.

Morphological and morphometric study of crustacean parasites within the genus Lernaeocera.

Two species of Lernaeocera are present in the southeastern North Sea. Lernaeocera lusci infects bib Trisopterus luscus, dragonet Callionymus lyra and sand goby Pomatoschistus minutas. L. minuta is a junior synonym of L. lusci. The second valid species, L. branchialis, infects whiting Merlangius merlangus. The two species can be morphologically separated by the antennary processes, which are present in L. lusci and absent in L. branchialis. Discriminant functions allow complete separation between L. lusci and L. branchialis. There is high intraspecific, host-dependent variability within L. lusci. Length of L. lusci is significantly influenced by host size, and body form is influenced by the site of attachment of L. lusci on at least one host (bib). It is suggested that L. lusci consists of 3 forms: f. lusci, f. minuta and f. lyra.

Sheina orri (Myodocopa: Cypridinidae), an ostracod parasitic on the gills of the epaulette shark, Hemiscyllium ocellatum (Elasmobranchii: Hemiscyllidae).

The cypridinid ostracod, Sheina orri, was found on the gills of healthy epaulette sharks, Hemiscyllium ocellatum, collected from the Great Barrier Reef, Australia. Seventeen of the 28 fish examined had ostracods attached to their gills. Detailed investigation of the gills and ostracods using light microscopy and scanning electron microscopy revealed that ostracods anchor themselves to the gill tissues using their mandibular and maxillular claws. These claws appear to be adapted for this purpose and the process of attachment causes some damage to the host tissues. The observation that ostracods were often located in distinct pockets, formed by local distortion of shark respiratory lamellae, strongly suggests that they had been attached to the gills for considerable time.

Parasites in cultured and feral fish.

Parasites, causing little apparent damage in feral fish populations, may become causative agents of diseases of great importance in farmed fish, leading to pathological changes, decrease of fitness or reduction of the market value of fish. Despite considerable progress in fish parasitology in the last decades, major gaps still exist in the knowledge of taxonomy, biology, epizootiology and control of fish parasites, including such 'evergreens' as the ciliate Ichthyophthirius multifiliis, a causative agent of white spot disease, or proliferative kidney disease (PKD), one of the most economically damaging diseases in the rainbow trout industry which causative agent remain enigmatic. Besides long-recognized parasites, other potentially severe pathogens have appeared quite recently such as amphizoic amoebae, causative agents of amoebic gill disease (AGD), the monogenean Gyrodactylus salaris which has destroyed salmon populations in Norway, or sea lice, in particular Lepeophtheirus salmonis that endanger marine salmonids in some areas. Recent spreading of some parasites throughout the world (e.g. the cestode Bothriocephalus acheilognathi) has been facilitated through insufficient veterinary control during import of fish. Control of many important parasitic diseases is still far from being satisfactory and further research is needed. Use of chemotherapy has limitations and new effective, but environmentally safe drugs should be developed. A very promising area of future research seems to be studies on immunity in parasitic infections, use of molecular technology in diagnostics and development of new vaccines against the most pathogenic parasites.

Cymothoid parasite Ceratothoa parallela inflicts great losses on cultured gilthead sea bream sparus aurata in Greece.

For the first time Ceratothoa parallela (Otto, 1828), a cymothoid isopod, is reported parasitizing cage-cultured gilthead sea bream Sparus aurata, in Greece. The specimens observed are larvae (Pullus secundus). They were found in the branchial and buccal cavity of young gilthead sea bream of 2 g mean body weight, upon introduction in the cages in an intensive cage farm facility. The species was previously known from several species of wild fish, particularly Sparidae (chiefly Boops boops) in the Mediterranean Sea, Adriatic Sea and Atlantic Ocean. However, this is the first documentation of this parasite in cage-cultured gilthead sea bream. Serious lesions were macroscopically visible and typical of a crustacean infection. The cumulative mortality over a 2 mo period was over 50%. The parasitic problem was not successfully dealt with due to high stocking densities and the non removal of the dead fishes, resulting in constant reinfection.

Effects of salinity on infection with Lerneaocera branchialis (L.) (Copepoda: Pennelidae).

Aquarium cod infected with Lerneaocera branchialis were exposed to gradually diluted sea water from salinity of 34.5 to 9.2 per thousand (S = 34.5-9.2) at a temperature of 8.5 C +/- 0.5 C. Osmolarity measurements of cod plasma, parasite hemolymph, and surrounding water showed that, unlike the cod, L. branchialis does not osmoregulate. Parasite survival is probably salinity-restricted below 16-20 S, which also is supported by its absence from Baltic waters. In waters of widely varying salinity, the parasite is not suitable as a biological tag to separate different cod populations. Hematocrit values were significantly lower in infected cod compared to noninfected fish. The pathogenic effect can be measured by the hematocrit reduction, which is correlated with the number of parasites on the host as well as the body size of the host.

Treatment of Argulus sp. infestation of river frogs.

Ten river frog tadpoles (Rana hecksheri) were collected from Pointsett State Park in South Carolina in April 1995. They were housed together in a tank at the North Carolina Zoological Park. Although no skin lesions were evident at collection, skin scrapings performed 4 weeks later revealed numerous immature and adult Argulus sp. on the tails and dorsal trunks of many of the tadpoles. The adult parasites were removed manually, and the tadpoles were treated with lufenuron (15 mg/l; Program, Novartis Animal Health, Greensboro, N.C.) and sodium chloride (3 g/l) in the tank water for 3 weeks. A single immature Argulus was found on a skin scraping on day 2 of treatment, and no parasites were seen thereafter on skin scrapings obtained through day 28 after the initiation of treatment. Metamorphosis occurred in all tadpoles within 4 weeks of initiating treatment. No deleterious effects of the treatment were noted.

The ecological-geographical characteristics of the parasitic crustacea of the Caspian Sea fishes.

In the Caspian Sea were found typically marine form--Pseudotracheliastes stellatus, specific for Acipenseridae, Thersitina gasterostei typical for sticklebacks rather euryhaline hosts, and Ergasilus briani, E. sieboldi, Paraergasilus rylowi, Lernaea elegans, L. esocina, Caligus lacustris, Argulus coregoni, A. foliaceus and Achtheres percarum normally infested the fishes in fresh water. The last one is characteristic for only Percidae, the remaining fresh-water crustaceans have far more wide host range. The majority of the parasitic crustaceans are noted in the coastal shallow areas of the Caspian Sea. Only P. stellatus is met too in the fairy deep places, where they are brought by Acipenseridae, which perform migrations of considerable extent.

Infestation dynamics of external parasites of saithe (Pollachius virens) from the North and Norwegian Seas.

An attempt has been made to examine the saithe's external parasites with respect to host age and the reproduction time of Clavella adunca in the North Sea. 1835 specimens of Pollachius virens caught in 1976-1980 and 1986 were examined. They were infested with Diclidophora denticulata, Udonella caligorum (Monogenea) and Clavella adunca, Lepeophtheirus pollachius, Caligus elongatus (Copepoda). The large number of adult females of C. adunca in winter and spring, the juvenile forms in summer and forms of 4th developmental phase autumn suggest that the reproduction cycle runs over the year in the North Sea with the peak between the late spring and early summer. The intensity values of infestation are highest for sexually mature fish but fall in older ones.

Parasitic crustaceans of Adriatic fishes.

45 species of Copepoda and 14 of Isopoda have been found on the South Adriatic (Montenegrian coast) fishes during the 10 years study. In addition to the check-list, some results of pathological and haematological investigations, showing that these parasites have a considerable impact on the growth, condition index and physiological state of hosts, are given.

[Colobomatoides splendidus n.g., n.sp. (Copepoda, Philichthyidae), a parasite of teleost fishes of the species Sparus (Sparidae) from the Tunisian coast]. / Colobomatoides splendidus n. g., n. sp. (Copepoda, Philichthyidae) parasite de poissons téléostéens du genre Sparus (Sparidae) des côtes de Tunisie.

After examination of the mucus ducts of the cephalic system in two species of teleostean fish from the coasts of Tunisia, Sparus ehrenbegi and Sparus caeruleostictus (Sparidae), a parasitic copepod belonging to the Philichthyidae, Colobomatoides splendidus n.g., n. sp. was found. The morphological study of this copepod is carried out.

[Metazoan parasites of carp (Cyprinus carpio Linnaeus, 1758) and vimba (Vimba vimba Linnaeus, 1758) in the Sapanca lake]. / Sapanca gölü'nde yasayan sazan (Cyprinus carpio Linnaeus, 1758) ve karabalik (Vimba vimba Linnaeus, 1758)'in Metazoan parazitleri.

In this study metazoan parasites of carp (Cyprinus carpio Linnaeus, 1758) and vimba (Vimba vimba Linnaeus, 1758) in the Lake Sapanca were investigated from January 2004 to December 2004. A total of 31 fish were investigated. Out of the 16 C. carpio, 13 were infected by parasites and of the 15 V. vimba, 11. The parasites found in C. carpio were: Dactylogyrus phoxini (Malevitskaya, 1949), Dactylogyrus extensus (Müller, Van Cleave, 1932), Gyrodactylus sp. Monogenoidea, Caryophyllaeus laticeps (Pallas, 1781), Bothriocephalus acheilognathi (Rud, 1808) Cestoidea, Diplostomum sp. Trematoda, Glochidium sp. Bivalvia. The parasites found in V. vimba were: Dactylogyrus sphyrna (Linstow, 1878), Dactylogyrus cornu (Linstow, 1878), Dactylogyrus cornoides (Gläser et Gussev, 1971) Monogenoidea, Aspidogaster limacoides (Dies., 1835), Posthodiplostomum cuticola (Nordmann, 1832), Tylodelphys clavata (Nordmann, 1832), Diplostomum sp., Tetracotyle sp. (Linstow, 1856) Trematoda, Neoechinorhynchus rutili (Müller, 1780) Acanthocephala, Glochidium sp. Bivalvia, Argulus foliaceus (Linnaeus, 1758), Ergasilus sieboldi (Nordmann, 1832) Crustacea. The parasites were investigated according to the place they were found in the host, prevalence and intensity of infections in the fish. Also the average intensity of the infection as well as the minimum and maximum intensities was estimated.

Human nasopharyngeal linguatuliasis (Pentasomida) caused by Linguatula serrata.

A human nasopharyngeal linguatuliasis was reported for the second time in Egypt. The patient (20 years old male) was presented with main conspicuous complaints, fever, urticaria (face and neck), coughing, vomiting and passage of small (less than 1 cm. in length) worm-like structures in his nasal discharge and vomitus. Symptomatic treatment was given followed by a single dose of praziquantel after identification of the causative parasite. Human linguatuliasis (pentastomiasis) was discussed.