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PubMed2006

Parasite fauna of the eel, Anguilla anguilla (Linnaeus, 1758), from the Polish part of the Vistula Lagoon.

INTRODUCTION: Eel is one of the most valuable commercial fish species of the Vistula Lagoon. For this reason its infection by non-indigenous species of parasites is the subject of the interest of sciencists. MATERIAL AND METHODS: A total of 90 eel specimens caught in the Polish part of the Vistula Lagoon were examined over the period of May-August 2005. The fish were subjected to standard procedures of parasitological examination and parasite identification. The fish were divided into two length classes: smaller and larger than 50 cm. To assess the effects of parasites on fish condition, the Fulton coefficient, expressed with the formula: WF = G x L(-3) x 100, was calculated. RESULTS: The fish were found to be hosts to 17 parasite taxa. The Ciliophora were represented by Trichodinella epizootica (Raabe, 1950); the Myxozoa by Myxidium giardi Cépede, 1906; the Digenea by Bunodera luciopercae (Müller, 1784), Deropristis inflata (Molin, 1859), Diplostomum spp., and Ichthyocotylurus platycephalus (Creplin, 1852); the Cestoda by Bothriocephalus claviceps (Goeze, 1782), Proteocephalus macrocephalus (Creplin, 1815), and Proteocephalus sp.; the Nematoda by Anguillicola crassus Kuwahara, Niimi et Itagaki, 1974, Camallanus lacustris (Zoega, 1776), C. truncatus (Rudolphi, 1814), and Hysterothylacium aduncum (Rudolphi, 1802); the Acanthocephala by Acanthocephalus lucii (Müller, 1776) and Corynosoma strumosum (Rudolphi, 1802); the Hirudinea by Piscicola geometra (Linnaeus, 1761); and the Copepoda by Ergasilus sieboldi Nordmann, 1832. All fishes were infected, and the mean intensity of all parasites was 4.8 inds. The nematode Anguillicola crassus was the most frequent parasite (67.8%, 4.2 inds), represented by all developmental stages, but mostly by adult specimens. The fish condition coefficient was somewhat higher in the eel larger than 50 cm (0.1746) than in those smaller than 50 cm (0.1734); in addition, only Anguillicola crassus-free fish showed a higher condition coefficient (0.1861), compared to the infected specimens (0.1715).

Anguilla↗
PubMed2006

[Incidence of intestinal parasites in municipal sanitary workers in Malatya].

The incidence of intestinal parasites is closely related to such factors as the socio-economic level of the society, nutritional and hygienic habits, climate, environmental conditions, infrastructure and degree of literacy. In this study, the municipal sanitary workers who are regarded as a high risk group in Malatya were examined for intestinal parasites. Cellophane slides and fecal samples from 241 workers were examined and intestinal parasites were found in 93 (39.0%). The most common parasite was Entamoeba coli (34). Other parasites detected include Enterobius vermicularis (32), Giardia intestinalis (22), Blastocystis hominis (8), Iodamoeba butschlii (5), Entamoeba histolytica (2), Taenia sp. (2), Chilomastix mesnili (2), Dientamoeba fragilis (2), Entamoeba hartmanni (1), Trichomonas intestinalis (1) Hymenolepis nana (1), and Ascaris lumbricoides (1). A training seminary was conducted in order to inform all the workers about means of protection. The workers were given suitable treatment and were called for control after a month. The examinations revealed a significant decrease in the incidence rate of parasites (qui-square test in dependent samples P<0.05). It was concluded that offering training seminaries for certain occupational groups under risk is efficient in terms of protection.

Adult↗
PubMed1997

Prevalence of schistosoma mansoni and intestinal parasites with evaluation of hepatic schistosomiasis in a rural area after governmental efforts (Gharbia governorate).

The study was carried out on 2136 individuals from Abo El-Gohoor village. Their ages ranged from 1-72 years with a mean of 28.3 +/- 22.4 years. They were 46.7% males and 53.3% females. The village was divided into sectors. The inhabitants of each sector were examined clinically with history taking through home visits. Three successive stool samples for each individual were examined by the concentration technique. Abdominal ultrasound was done for hepatic and splenic assessment. Rectal biopsy was done for 200 subjects with negative stool samples for Schistosoma mansoni (S. mansoni) ova. Sex distribution was equal in this group. Their ages ranged from 18 to 45 years with a mean of 30.1 +/- 9.5 years. S. mansoni prevalence was 19.3% of individuals through stool examination and 12.5% out of 200 individuals with active schistosomiasis after rectal biopsy (the total prevalence was approximately 29.4%). Hepatic schistosomiasis was 18.8%. Hepatomegaly, hepatosplenomegaly, hepatic fibrosis without and with ascites were 6.0%, 8.8%, 2.5% and 1.5% of examined patients, respectively. The prevalence of intestinal parasites was 37.5% and 27.8% for E. histolytica and G. lamblia, respectively, 9.2% for H. nana, 6.2%, 9.6%, 2.4% and 1.5% for A. lumbricoides, E. vermicularis, T. trichura and A. duodenale, respectively and F. gigantica was 0.4%. A total of 84.6% of examined subjects had parasitic infestations, 60.2% had one parasite, 19.6% had 2 parasites, 4.2% had 3 parasites and 0.7% had 4 parasites. The study revealed some success of governmental efforts for control of schistosomiasis. The prevalence of S. mansoni through stool examination showed a prevalence lower than that reported before but which does not represent the actual prevalence of S. mansoni and rectal biopsy in addition gave more accurate results.

Adolescent↗
PubMed2000

Parasitic infections and maternal awareness of preschool children in Karmouz district, Alexandria.

Intestinal parasitic infections are widespread especially among preschool children living in poor areas. Also pediculosis has been perceived as a public health nuisance for decades. A cross-sectional study was conducted on 256 children and their mothers in a poor urban district to assess mothers' knowledge and practices as regards parasitic infections and infestations that may be present in her preschool child, and to correlate the presence of these infections with her awareness. A pre-designed questionnaire that included socio-demographic data, items to assess mothers' knowledge of sources and preventive measures of parasitic infections and infestations and her practices was completed. A stool sample was collected from children and examined using formol-ether technique and Sellotape technique was used to detect Enterobius vermicularis. Pediculus capitis was diagnosed by inspection of the scalp and was found to be the most prevalent parasite found in 58.9% of those children followed by Enterobius vermicularis in 46%. A strong positive association between pediculosis and enterobiasis was detected (phi coefficient = 0.956, p < 0.001). Socioeconomic level affected both knowledge and practices scores where one point change in knowledge score or socioeconomic score caused an increase in practice score of 0.279 and 0.071, respectively. Also higher risk of pediculosis was found to be significantly associated with female sex and low socioeconomic level. An increase of one point in practice score showed a decrease in the log likelihood ratio of enterobiasis of 14.3%. The majority of mothers (77.3%) were found to be aware that their children had a parasitic infection, which was significantly associated with results of stool analysis. This indicates that awareness building is not enough to be of practical benefit. Appropriate and detailed control methods of parasitic infections and pediculosis must be taught and applied by parents and community. Socio-economic development, organized health programs and motivation should be undertaken to help today's children.

Adult↗
PubMed1991

Current status of food-borne parasitic zoonoses in India.

Food-borne parasitic zoonoses have a major impact on the health and economy in developing countries in the tropics and sub-tropics. Complex socio-economic and socio-cultural factors impact on the maintenance of parasitic zoonoses. In addition to human disease, some of these parasites are responsible for economic loss to livestock production. Throughout India, problems of food-borne parasitic zoonoses differ because of varied food habits. Other factors, however, such as unhygienic living conditions, lack of education, poor personal hygiene, poverty and occupation, also contribute to the dissemination of parasitic infections. The present status of various food-borne parasitic zoonoses are briefly given here.

Animals↗
PubMed1990

Adaptation of an introduced host to an indigenous parasite.

Introduction of striped bass to the west coast from the east coast of the U.S.A. provided the opportunity to study a recent host-parasite association in a marine system. An indigenous species of parasite was known to induce pathological changes in the introduced population. Because the west coast population has been in association with this pathogenic parasite more than 20 generations, we predicted that the host reaction of the west coast population would be less severe compared to that of the naive east coast stock of striped bass. This prediction was tested by conducting reciprocal infection experiments with east and west coast hosts and parasites. The group of west coast striped bass had a lower intensity of infection and exhibited less tissue damage compared to the group of east coast striped bass. We suggest that selection has acted only on the host and is driven by parasite-induced host mortality. This type of 1-sided selection is in contrast to present models of the evolution of host-parasite associations.

Animals↗
PubMedDate not supplied

Intestinal parasites in refugee claimants: a case study for selective screening?

The medical profiles of 1,967 refugee claimants to Montreal, Quebec, Canada from January 1987 to July 1987 were reviewed to evaluate the importance of imported intestinal parasite infection in this group and to re-examine the screening policy governing these infections. An overall infection rate of 29.3% was obtained for pathogenic parasites, where helminths were four times more frequently found than the protozoa Entamoeba histolytica and Giardia lamblia. Age, sex, years of schooling, country of origin and level of eosinophilia were found to be associated with infection, with country of origin being the strongest predictor of infection. These results document the parasite infection in a select group of immigrants which would not have been identified and treated if a special program of screening were not in operation. We suggest that the present immigration policy of no screening for intestinal parasite infection be at least modified to include a recommendation that new arrivals, who are considered to be at high risk for parasite infection, be informed that an examination for parasites would be beneficial to their personal health.

Adolescent↗
PubMed1989

Pattern of intestinal parasitic infection in preschool children in Riyadh, Saudi Arabia.

A total of 1,167 stool specimens collected from 0.6-6 years old patients attending King Abdel Aziz University Hospital (KAUH) in Riyadh, were examined for intestinal parasites. Of these 243 (20.8%) were positive. Giardia lamblia (13.5) and Enterobius vermicularis (4.2%), were the commonest parasites found. Other parasites present include Ascaris lumbricoides, Entamoeba histolytica and Hymenolepis nana. Abdominal pain (38.6%) and diarrhoea (27.6%) were the most common causes of referral presented among both males and females examined groups. Out of 211 patients positive for different parasites and showing different causes of referral, 45.5% were accompanied with abdominal pain and 22.3% having pruritus ani, while the percentage of patients having diarrhoea and positive for different parasites (9.5%) are less. It has been concluded that diarrhoea is not a major sign of parasitic infestation in 0.6-6 years old age group. Other causes of referral include, loss of appetite, underweight and failure to thrive which are mainly associated with Giardia lamblia infection.

Age Factors↗
PubMed1978

The conflicting role of parasitic infections in modulating the prevalence of asthma.

Nothwithstanding difficulties associated with the limitations of survey techniques and methodology employed to define asthma, the evidence accumulated to date suggests that the reported differences in the prevalence rates of this disease from country to country and within local populations of the one country are real. It is accepted that allergy is not the sole cause of asthma but nonetheless hypersensitivity to environmental allergens is a significant triggering factor in most countries of the world. Comparisons between countries might therefore be influenced by the time of the year when the survey is taken since the prevalence of seasonal asthma would be higher in the period of pollinosis. Environmental factors, and in particular the relative atmospheric concentrations of pollens and the density of house dust mite (D. pteronyssinus and D. farinae) in dwellings, must therefore be considered when accumulating prevalence data. The prevalence rate for childhood asthma is high in Australia, United Kingdom, United States of America and New Zealand, and medium to low in the Scandinavian countries and Switzerland. It is not clear what factors contribute toward these differences since several studies indicate that racial characteristics per se are not pre-eminent in defining susceptibility to asthma. Most surveys indicate that the prevalence of childhood asthma is low to very low among low-income populations living in tropical areas. While it is possible to implicate inadequate diagnosis, genetic factors, nutritional status and allergen exposure as factors contributing towards the low prevalence, it has become fashionable to attribute this observation to the influence of certain helminthic infections. Parasites stimulate the production of high levels of serum IgE, the bulk of which has as yet an undetermined specificity. The suggestion that this IgE blocks mast cell receptors leaving insufficient sites available for sensitization by allergen-specific IgE antibody is attractive. However, since the kinetics of binding to mast cell receptors is unlikely to be the same for all IgE molecules, irrespective of their specificity, this hypothesis appears to be an oversimplification of the problem. It is more likely that parasitic infections repress the synthesis of IgE antibody to environmental allergens, although the mechanism for this is unclear. Circumstantial evidence suggests that the time course of exposure to parasites versus sensitization by environmental allergens may be critical. Another possibility is that parasitic infections in some way nullify the effect of allergens at the level of the target organ, perhaps through the modulating role of eosinophils. If it is established that parasitic infections, particularly in early childhood, suppress the capacity of potentially atopic children to develop asthma and other allergic disorders, there would be some justification in attempting to circumvent allergic disorders in susceptible individuals by a harmless preparation of parasite antigens.

Adolescent↗
PubMed1987

Mechanism of escape of exoerythrocytic forms (EEF) of malaria parasites from the inhibitory effects of interferon-gamma.

We have studied the mechanism of inhibition by interferon-gamma (IFN-gamma) of the development of exoerythrocytic forms (EEF) of Plasmodium berghei in the livers of rats. At the time corresponding to the maximum development of EEF (44 hr after injection of sporozoites), the livers of the IFN-gamma-treated rats contained less parasite DNA as compared with controls. Twenty-four to 72 hr later, the livers of both groups of animals were free of parasites; that is, IFN-gamma treatment does not delay the development of the EEF. The decrease in parasite DNA observed in the IFN-gamma-treated rats was due to a diminution in the number, but not the size, of EEF. It appears, therefore, that treatment with the lymphokine either destroys the parasites or does not affect their replication. To study the mechanism of resistance to IFN-gamma of a small population of EEF, we subjected the parasites to four cycles of selection by IFN-gamma. The parasites from the "selected" and "nonselected" populations were equally susceptible to inhibition by IFN-gamma, indicating that the escape from IFN-gamma activity is not inherited.

Animals↗
PubMedDate not supplied

Intestinal parasites in the Camiri, Gutierrez and Boyuibe areas, Santa Cruz Department, Bolivia.

A parasitological study was carried out on 381 apparently healthy subjects from Camiri, Boyuibe, Gutierrez. Intestinal parasites and non-pathogenic protozoa were present in 78.7% of the population sampled; multiple infections were observed in 67.7% of the parasitized individuals. The protozoon most commonly found was Entamoeba coli (in 40.7% of specimens), followed by Giardia intestinalis (30.7%), Iodamoeba bütschlii (10%), Chilomastix mesnili (8.7%). Other protozoon parasites also present were Enteromonas hominis (3.4%), Retortamonas intestinalis (2.4%), Cryptosporidium (2.1%), Endolimax nana (2.1%), Balantidium coli (1.8%) and Pentatrichomonas hominis (0.8%). The helminths observed were hookworms (28.6%), Trichuris trichiura (19.7%), Ascaris lumbricoides (9.7%), Hymenolepis nana (8.7%), Trichostrongylus (5.5%), Strongyloides stercoralis (1.8%), Taenia (5 cases) and Enterobius (6 cases). Prevalence for nematodes is probably underestimated in the 3-9 years age group because of a mebendazole treatment given 5 weeks before the survey, under a Program of P D C of the Ministry of Health. The sample from Camiri was found to be the most parasitized (84.1%). An extraordinarily high infection rate was found in two urban institutions, as well as in Itanambicua, a rural community close to Camiri. No significant differences were observed in parasitic prevalence between rural and urban environments. Exposure to contamination with human and animal faeces, overcrowding and poor sanitation habits are some of the factors responsible for the parasitic situation evidenced.

Adolescent↗
PubMed1988

Host-parasite relationships of caryophyllaeid cestodes and aquatic oligochaetes: II. Effects of host age and mixed infections.

Experiments were conducted to assess the relationship between annelid age and susceptibility of the annelid as an intermediate host for a caryophyllaeid, as well as the effect a mixed-species infection has on rate of metacestode development and parasite mortality. Four host-parasite systems were studied: Biacetabulum biloculoides and Hunterella nodulosa in Limnodrilus hoffmeisteri and Glaridacris catostomi in Ilyodrilus templetoni and Tubifex tubifex. Annelids were divided into 3 age classes: immature, approximately 7 days old; intermediate, approximately 14 days old; and mature, approximately 30 days old. Immature oligochaetes in all groups were more susceptible to infection, their parasites exhibited a lower mortality rate than 30-day-olds, and the total number of parasites in this group was higher than for the other age classes. Metacestodes reached the infective stage earlier in immature as compared to older oligochaetes. Interspecific competition between B. biloculoides and H. nodulosa resulted in increased parasite mortality and a slower rate of parasite development for the species that became established second. A prior infection with one species of cestode also affected the susceptibility of L. hoffmeisteri to infection with another species.

Age Factors↗
PubMed1983

Taenia taeniaeformis (Cestoda) in the rat: ultrastructure of the host-parasite interface on days 8 to 22 postinfection.

The host-parasite interface was examined at the ultrastructural level 8 to 22 days postinfection (DPI) with metacestodes of Taenia taeniaeformis in the rat. Throughout this phase of development the parasite surface was invested with a dense surface coat of complex microtriches. At 8 to 14 DPI the plasma membrane of each microthrix extended beyond the distal end of the electron-dense tip, forming a slender tubular streamer over 10 microns long; by 18 DPI these had shortened and withered. Host cell processes interdigitated with the microtriches without evidence of harm to the parasite surface or the underlying tegument. The cells, on the other hand, became damaged, and their contents were shed into the matrix surrounding the microtriches. Lipid inclusions appeared within the parasites, and in the cytoplasm of surrounding inflammatory cells. By 22 DPI fibroblastic activity had resulted occasionally in the formation of a capsule surrounding a free-floating cysticercus, while in others intense granulocytic infiltration persisted with abutment and intermeshing of host cell and parasite surface processes; however there was still no evidence of any adverse effect on the microtriches, though many granulocytes were clearly pyknotic and degenerating. Evidently, the vigorous cellular response of the host is ineffective in either containing the expansion of the parasite or compromising the integrity of its surface membrane. The changing characteristics of the microtriches may be related to the need for dissolution of both intercellular matrices, and host cells as the vesicular organism rapidly increases in volume.

Animals↗
PubMed1984

Influence of parasitic infection on food intake.

The results of controlled experiments have demonstrated unequivocally that host food intake is often altered during the course of infections with eukaryotic parasites. Generally, host food intake is reduced depending on either the infective dose given to the host or the number of established parasites present. The onset in the reduction of host food intake varies according to the species of parasite involved and may be related to a particular developmental stage or event during the course of the host-parasite relationship. Some of the many sensory, neural, and hormonal factors that are now considered to modulate food intake in healthy animals are known to be affected during certain host-parasite relationships, and it is tentatively suggested that these physiological perturbations may initiate the observed changes in host food intake. Not unexpectedly, human appetite for food and food intake have been reported to become depressed during parasitic infections.

Animals↗
PubMed1984

Intestinal parasites in pediatric patients with diarrhoeal diseases in Bangkok.

Stool examinations of 147 pediatric patients with diarrhoeal disease were carried out at Siriraj Hospital, Bangkok by using the direct-smear technique. Stool of 27 patients (18.4%) were positive for intestinal parasites. Children under one year of age were free of intestinal helminths and protozoa. Parasites were equally prevalent in males and females and without any age group predilection. The prevalence of intestinal parasites were Entamoeba histolytica 6.8%, Giardia lamblia 6.1%, others were Ascaris lumbricoides, hookworm, Trichuris trichiura and Balantidium coli. Although the incidence of parasitism was not high as to be the main causatic agent of pediatric diarrhoea, the intestinal parasites may increase susceptibility to infection with other intestinal pathogens. The diagnosis of intestinal parasitoses can be determined by a simple direct faecal-smear technique and so that specific therapy can be instituted without delay in management of parasite-related diarrhoeas.

Age Factors↗
PubMed1982

Intestinal parasites in asymptomatic adult Southeast Asian immigrants.

All previous studies of intestinal parasites in Southeast Asian refugees have included immigrants with and without symptoms. In order to determine the prevalence of intestinal parasites in asymptomatic Southeast Asians, 226 adult refugees were studied who had no symptoms or signs suggestive of intestinal parasitism and who submitted one to three stools for examination. Fifty-four percent of these asymptomatic adults were infected with one or more potential pathogens, 22 percent with Ascaris, 20 percent with hookworm, 11 percent with Opisthorchis sp, 7 percent with Trichuris, 5 percent with Strongyloides, 5 percent with Giardia, and 2 percent with Entamoeba histolytica. Laotians and Cambodians, persons who stayed in Thai refugees camps, and patients with anemia or eosinophilia were more likely than other refugees to harbor pathogenic parasites. Nonetheless, refugees without these characteristics were often infected, and no single characteristic excluded any refugee from a high probability of being parasitized. There is a high prevalence of potentially pathogenic parasites in asymptomatic adult Southeast Asians, similar to that reported in refugees unselected for the presence or absence of symptoms.

Adult↗
PubMed1981

Effects of naturally acquired mixed helminth parasitism in yearling dairy calves.

The effects of Strongyle parasitism were studied in yearling calves. One group (4 calves) was a noninfected control, and 2 groups (4 calves each) were infected by exposure on pasture to the same type and degree of parasitism. One of the 2 infected groups were given coumafos at 4-week intervals and the other was not treated. Few significant differences were found between the control and infected groups in hematologic and serum glucose and urea nitrogen values. The control group gained an average of 2.2 kg/week, as compared with 1.0 kg/week, as compared with 1.0 kg/week for the treated group. The parasitized-untreated group lost 0.2 kg/week. Overall, the control group gained 26.8 kg for the 12-week period, which was significantly different (P less than 0.05) from an 11.4-kg gain by the parasitized-treated group and a 2.3 kg loss for the parasitized-untreated group. In the face of constant pasture challenge exposure, most adult worms were eliminated from the drug-treated animals, but the adverse effects of parasitism were not reversed.

Animals↗
PubMed1995

A survey of intestinal parasites in students of Adult Educational Center in Sivas, Turkey.

The prevalence of intestinal parasites in students of Adult Educational Center (Halk Egitim Merkezi) in Sivas, Turkey was assessed. All of the students were females and their age ranged from 12 to 46 with a mean age of 19. Diagnosis was made following examination of stool specimens and cellophane tape preparations (CTP). From each stool specimen only one preparation prepared in saline was searched for both protozoon and helminth parasites. A total of 524 stool specimens and 504 CTP were examined. One or more parasites were detected in 34.5% the former and 23.8% of the latter. When the findings in both specimens were combined the infection rate raised to 48.0%. 176 of the 485 students harboured one, whereas 57 had more than one parasite; 87 had only protozoa, 104 only helminths whereas 42 were infected with parasites of the two groups. The rate of parasites found was as follows: G. intestinalis 8.2%, E. histolytica 1.2%, E. coli 17.9%, A. lumbricoides 2.3%, T. trichiura 0.8%, E. vermicularis 12.6%, T. saginata 16.7%, H. nana 1.0%, and others 0.6. Findings were evaluated from several points.

Adolescent↗