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PubMed2001

[Importation of parasites by tourism and animal trading].

International transport of animals is associated with an enhanced risk of import of a number of parasite species that are not endemic in Germany. Pets accompany tourists on journeys all over the world, but in particular to southern Europe, and dogs are increasingly imported from (sub-)tropical countries for reasons of animal welfare. Veterinary practitioners are thus confronted with parasites that are unusual in their patients. The specific transmission routes determine whether an imported parasite is able to become endemic. Although parasites eradicated in Germany such as Trypanosoma equiperdum and Tritrichomonas foetus may be principally imported they are unlikely to re-establish due to the current epidemiological conditions. Imported animals that harbour parasites which may occur naturally but are currently rare in Germany are a potential source of increased infection risk. Certain areas in Germany have probably become endemic for Babesia canis and the respective vector tick Dermacentor reticulatus has been found. Whether other vector borne parasitic diseases such as leishmaniosis or heartworm disease have the potential to spread into Germany is still a matter of debate.

Animal Welfare↗
PubMedDate not supplied

Intestinal parasites infestation and anemia in primary school children in Gaza Governorates--Palestine.

A comparative study was carried out to identify the prevalence of anemia, nutritional indices and intestinal parasitic infestation in primary school children. The target population included 209 pupils aged 6-11 years, attending schools in two areas, Rimal area (urban) and Jabalia village (rural), in Gaza Governorates. Prevalence of intestinal parasites was high in Jabalia village (more than 53%) in comparison to Rimal area (33%). The main intestinal parasites were Entamoeba histolytica, Giardia intestinalis and Ascaris lumbricoides. Polyparasitism frequency is higher especially in rural area. In both areas anemia showed a high prevalence in children due to malnutrition and intestinal parasitic diseases. There was no association between intestinal parasitic infestation and children growth, but there was association between anemia and intestinal parasitic infestation in children, particularly in rural area. The correlation between anemia and mixed infestation reaches a highly significant level.

Anemia↗
PubMed2002

[Gastrointestinal disorders in Guatemala and their relationship with parasitic infections].

BACKGROUND: To determine the frequency of symptoms suggestive of functional gastrointestinal disorders and their relation to parasite infections in a developing nation. MATERIAL AND METHODS: 174 consecutive patients was seen in a gastroenterology clinic in Solola (Guatemala). RESULTS: Symptoms suggestive of irritable bowel syndrome was diagnosed in 37 patients (21%), irritable bowel syndrome with dyspeptic syndrome in 26 (15%) and dyspeptic syndrome in 24 (14%). Forty-two patients (24%) had been diagnosed of parasitation in the past. Such patients had a higher risk of suffering symptoms suggestives with functional gastrointestinal disorder (OR 6,335 CI 95% 2.72-14-75). Fifty-nine patients (34%) were subjected to parasite examination in stools; of these, 13 proved positive. In this same group of patients the risk of functional gastrointestinal problems was likewise higher among the subjects with parasite infection (p < 0.05). In turn, 41 patients (49%) with symptoms suggestives of gastrointestinal functional disorders were or had previously been diagnosed of parasite infection. CONCLUSIONS: Symptoms suggestives of functional gastrointestinal disorders are frequent in developing regions and its was in relation to intestinal parasites.

Adult↗
PubMed2002

[Gastrointestinal disorders in Guatemala and their relation with parasitic infections].

BACKGROUND: To determine the frequency of symptoms sugestive of functional gastrointestinal disorders and their relation to parasite infections in a developing nation. MATERIAL AND METHODS: 174 consecutive patients was seen in a gastroenterology clinic in Solola (Guatemala). RESULTS: Symptoms suggestive of irritable bowel syndrome was diagnosed in 37 patients (21%), irritable bowel syndrome with dyspeptic syndrome in 26 (15%) and dyspeptic syndrome in 24 (14%). Forty-two patients (24%) had been diagnosed of parasitation in the past. Such patients had a higher risk of suffering symptoms suggestives with functional gastrointestinal disorder (OR 6,335 CI 95% 2.72-14-75). Fifty-nine patients (34%) were subjected to parasite examination in stools; of these, 13 proved positive. In this same group of patients the risk of functional gastrointestinal problems was likewise higher among the subjects with parasite infection (p < 0.05). In turn, 41 patients (49%) with symptoms suggestives of gastrointestinal functional disorders were or had previously been diagnosed of parasite infection. CONCLUSIONS: Symptoms suggestives of functional gastrointestinal disorders are frequent in developing regions and its was in relation to intestinal parasites.

Adult↗
PubMed2002

Prevalence of parasitic infections in a rural area of Karachi, Pakistan.

OBJECTIVE: To find the prevalence of human intestinal pathogenic parasites. SETTING: The study was conducted in Konkor, Gadap, District East, Karachi. METHODS: After taking the verbal consent, all the villagers, selected by area sampling technique were interviewed by a structured questionnaire and then each person in the house was provided with a clean, plastic container to collect the stool samples. Samples were examined using normal saline, iodine preparation and zinc floatation technique where appropriate. RESULTS: Out of 263 residents 185 tested for intestinal parasites and 88 (47.5%) had pathogenic parasites. The distributions of parasites were Giardia lamblia 50% and Entamoeba histolytica 48.86%. Statistically none of the socio-demographic variables were associated except education and age group. CONCLUSION: In the light of the study result it is concluded that there is a high prevalence of parasitic infection in the community and an intervention strategy including health education program should be designed and implemented to control parasitic infections.

Adolescent↗
PubMed2001

[Second sampled survey on the distribution of human parasites in Zhejiang Province].

OBJECTIVE: Twenty-six species of human parasites were recorded in Zhejiang Province in 1987-1989 as a part of the national investigation on the distribution of human parasites, and the total prevalence was 80.2%. In order to find out possible changes on the composition of parasite species and decrease of prevalence after control intervention particularly mass chemotherapy in the past years and provide evidence for an improved control strategy, the second sampled survey was carried out from 1998 to 1999. METHODS: Ten counties were identified randomly out of 28 counties where the last survey was conducted following the same sampling method. Same technics were used for case detection and data processing. RESULTS: The total infection rate in a sample of 15,698 was 22.84% was 22.84% in 30 investigation spots in 10 counties, and 17 species of parasites were revealed. The overall prevalence was reduced by 71.51% in comparison to that of 1989, and the number of parasite species was 17, 9 less than that of the last investigation. CONCLUSIONS: The prevalence of human parasites has greatly declined in this province due to the socioeconomic development and adoption of comprehensive control measures focusing on mass chemotherapy in the past decade.

Adolescent↗
PubMed2003

Intestinal parasitic infestations among children in an orphanage in Pathum Thani province.

Infection caused by intestinal parasites is still a common health problem especially in children from developing countries. Orphans are a group of underprivileged population in society. To evaluate the intestinal parasitic infections in children in an orphanage in Pathum Thani province, Thailand, stool samples were collected during a cross-sectional study in April 2001. Examination for intestinal parasites were performed by using simple smear, formalin-ether concentration, Boeck and Drbohlav's Locke-Egg-Serum (LES) medium culture and special staining (modified acid-fast and modified trichrome) techniques. A total of 106 pre-school orphans (60 males and 46 females), aged 10.0-82.0 months, were recruited for the study. There were 86 individuals (81.1%), 45 males and 41 females, infected with at least one parasite. Interestingly, most of the parasites identified were protozoa. Blastocystis hominis was found at the highest prevalence (45.2%). The infections caused by Giardia lamblia was 37.7 per cent and Entamoeba histolytica was 3.7 per cent. Other non-pathogenic protozoa found were Trichomonas hominis (39.6%), Entamoeba coli (18.8%), and Endolimax nana (3.7%). The only one case of helminth parasite detected was Strongyloides stercoralis (0.9%). The sensitivity for detection of B. hominis and T. hominis was increased by the LES culture technique. No history of diarrhea symptoms were recorded among these orphans. However, during the investigation, stools of all infected cases were noted for six characteristics including formed, soft, loose, mucous, loose-watery and watery. The present study emphasized the problems of protozoan infections among these orphans. Health educations as well as routine surveillance is necessary in order to control the infections.

Child↗
PubMed1992

Host-parasite interactions in Taenia solium cysticercosis.

Human neurocysticercosis results from infestation of the central nervous system with the metacestode form (tissue cyst) of Taenia solium. Cysticercosis is being increasingly recognized as a cause of neurologic symptoms in residents and emigrants from developing countries. Taeniid parasites have developed elaborate mechanisms to persist in the tissues of their intermediate hosts. The invasive larvae, termed oncospheres, are susceptible to antibody and complement. However, by the time that the host has generated an antibody response, the parasites have begun to transform to the more resistant metacestode form. The metacestodes also have means of evading complement-mediated destruction, including paramyosin, which inhibits C1q; taeniaestatin, which inhibits both classical and alternate pathways (likely by inhibiting factor D and C3 esterase); and sulfated polysaccharides, which activate complement away from the parasite. Similarly, antibody does not seem to be able to kill the mature metacestode. The parasites may even stimulate the host to produce antibody, which could be bound via Fc receptors, and used as a source of protein. Finally, taeniaestatin and other parasite molecules may interfere with lymphocyte proliferation and macrophage function, thus paralyzing the cellular immune response. Because the symptoms of neurocysticercosis are typically associated with a brisk inflammatory response, we hypothesize that disease is primarily the result of injured or dying parasites. This hypothesis raises important questions in assessing the role of chemotherapy in the management of neurocysticercosis as well as in evaluation of clinical trials, most of which have been uncontrolled.

Animals↗
PubMed1964

MERMITHID PARASITES OF BLACKFLIES.

Mermithid nematodes parasitize invertebrates only. A general account is given of their parasitism and the consequent mortality of blackflies. The author begins with a review of records of mermithid and blackfly association from different parts of the world and comments on the global distribution of the parasite. He discusses the life-histories of the parasites, stressing their adaptations to the moving environment of the aquatic stages of the blackfly and to the aerial environment of the adult. It is noted that the parasite usually kills its host upon emergence and has a restricted host range. Mermithids must be considered as selective mortality factors against blackfly populations. A survey of European and North American literature leads to conclusions concerning the role of the parasite in the natural regulation of blackflies. The possibility of utilizing these nematodes as biological control agents is discussed.

Animals↗
PubMed2003

Opportunistic intestinal parasites among children with chronic liver disease.

Two hundred children were included in this study, 80 patients showing clinical and/or biochemical evidence of chronic liver disease, 80 immuno-compromised children due to causes other than chronic liver disease and 40 healthy control. All were subjected to detailed history, thorough clinical examination, investigated by liver function tests and stool examination by special techniques for opportunistic intestinal parasites. Autoimmune chronic hepatitis represented 12.5% of cases with chronic liver disease, hepatic schistosomiasis 30%, congenital cholestasis 25%, chronic viral hepatitis 20% and metabolic liver diseases 12.5%. The incidence of opportunistic intestinal parasites with chronic liver disease (92.5%) was nearly similar to the immuno-compromised ones (90%) and significantly higher than controls (30%). Mixed infection was not detected in controls while 57.5% of patients with chronic liver disease and 35% of immuno-compromised were infected by 2 parasites and 12.5% of each group was infected by more parasites. The commonest parasites were G. lamblia, E. histolytica and C. parvum but no Strongyloides stercoralis was detected. Children with chronic liver disease can be considered immuno-compromised and are liable to infection by opportunistic intestinal parasites.

Adolescent↗
PubMed2004

Intestinal parasitic infections in HIV/AIDS and HIV seronegative individuals in a teaching hospital, Ethiopia.

The magnitude of intestinal parasitic infection in human immunodeficiency virus (HIV) /AIDS patients requires careful consideration in the developing world. However, there have been very few studies addressing this issue in Ethiopia. This study was conducted to determine the prevalence of intestinal parasitic infection in HIV/AIDS patients at Jimma Hospital, Southwest Ethiopia, between January and February 2002. Stool specimens from HIV/AIDS patients and control groups were screened for intestinal parasitic infections using direct and formalin-ether sedimentation concentration methods. Out of 78 HIV/AIDS patients, 52.6% (41/78), and out of 26 HIV-negative individuals, 42.3% (11/26), were infected with one or more types of intestinal protozoa and/or helminthes. The parasites detected among HIV/AIDS patients included Ascaris lumbricoides (30.8%), Blastocystis spp. (14.1%), Entamoeba histolytica (10.3%), Trichuris trichiura (6.4%), Strongyloides stercoralis (5.1%), Giardia lamblia (3.8%), Schistosoma mansoni (2.5%), hookworm species (2.5%), and Taenia spp. (1.3%). Multiple infections were more common among HIV/AIDS patients. Blastocystis spp. were found to be significantly higher in HIV/AIDS patients than in controls (P < 0.05). The magnitude of intestinal parasitic infection was high both in HIV/AIDS patients and in controls. Routine examinations of stool samples for parasites would significantly benefit the HIV-infected and uninfected individuals by contributing to reduce morbidity.

AIDS-Related Opportunistic Infections↗
PubMed1992

The immune defensive mechanism in parasitic infection with eosinophilia.

This study was attempted to assess the extent of stimulation of the immune system in some patients suffering from parasitic infection with eosinophilia. Eighty-eight cases were selected, they included 10 apparently healthy, 10 suffering from different atopic disorders associated with eosinophilia and free from parasitic infections and 68 patients suffering from different parasitic infections associated with marked eosinophilia. The results showed a highly significant increase in the absolute eosinophil count in the atopic group while the parasitized group showed a moderate increase. The IgE serum level was increased in both atopic and parasitized groups. The cellular immunity expressed by phagocytic power of neutrophils was more depressed in parasitized than atopic group.

Eosinophilia↗
PubMed2005

Parasite burden and constitution of major histocompatibility complex in the Malagasy mouse lemur, Microcebus murinus.

We investigated the importance of the major histocompatibility complex (MHC) constitution on the parasite burden of free-ranging mouse lemurs (Microcebus murinus) in four littoral forest fragments in southeastern Madagascar. Fourteen different MHC class II DRB-exon 2 alleles were found in 228 individuals with high levels of sequence divergence between alleles. More nonsynonymous than synonymous substitutions in the functional important antigen recognition and binding sites indicated selection processes maintaining MHC polymorphism. Animals from the four forest fragments differed in their infection status (being infected or not), in the number of different nematode morphotypes per individual (NNI) as well as in the fecal egg counts (FEC) values. Heterozygosity in general was uncorrelated with any of these measures of infection. However, a positive relationship was found between specific alleles and parasite load. Whereas the common allele Mimu-DRB*1 was more frequently found in infected individuals and in individuals with high NNI and FEC values (high parasite load), the rare alleles Mimu-DRB*6 and 10 were more prevalent in uninfected individuals and in individuals with low NNI and FEC values (low parasite load). These three alleles associated with parasite load had unique amino acid motifs in the antigen binding sites. This distinguished them from the remaining 11 Mimu-DRB alleles. Our results support the hypothesis that MHC polymorphism in M. murinus is maintained through pathogen-driven selection acting by frequency-dependent selection. This is the first study of the association of MHC variation and parasite burden in a free-ranging primate.

Analysis of Variance↗
PubMed2005

Intestinal parasite isolates in AIDS patients with chronic diarrhea in Gondar Teaching Hospital, North west Ethiopia.

Chronic diarrhea is one of the major AIDS-defining illnesses in WHO Classification and occurs in 60-90% of HIV-infected patients in Africa. We did a case series study on parasite isolation in stool samples of AIDS patients with chronic diarrhea using wet-mount, Formol-Ether concentration technique and Modified Acid-Fast staining method in Gondar Teaching Hospital between January and September 2000. Seventy AIDS patients with chronic diarrhea were included in the study. Wasting syndrome was the clinical presentation in (97%) almost all AIDS patients who had chronic diarrhea. Intestinal parasites were detected in 41 out of 70 diarrheal specimens in AIDS patients. Multiple parasitic injections were detected in three diarrheal specimens. Intracellular parasite, (29%) Cryptosporidium parvum, and mucosal parasite, (17%) Strongyloides stercoralis were the frequently isolated parasites in diarrheal specimens of AIDS patients, accounting for 80% diarrhaegen pathogens among positive specimens. Cryptosporidium parvum, under-estimated cause of chronic diarrhea in immunocompetent adults, was found to be the prominent diarrheagen in AIDS patients in this study, similar with other studies in different African countries.

AIDS-Related Opportunistic Infections↗
PubMedDate not supplied

[Seasonal distribution of gill parasites in fishes from fee-fishing at Guariba, São Paulo State, Brazil].

This study was accomplished with the objective of knowing the seasonal distribution of the main species of parasites causes of branchial damages to the fish from fee-fishing at Guariba, State of São Paulo. This city is situated at 21 degrees 15'22'' S, 48 degrees 18'58'' W, in altitude 595 meters. This research was conducted between April, 1997 to March, 1999. From 408 fishes examined, 29.1% of them were infested by the protozoans e metazoans. Leporinus macrocephalus showed the highest parasitism by Trichodina sp., although Piaractus mesopotamicus and Cyprinus carpio were also parasited. Piscinoodinium pillulare infestation were found in L. macrocephalus, P. mesopotamicus, C. carpio e Colossoma macropomum. Monogenetics metazoan have largely been observed in L. macrocephalus, P. mesopotamicus, C. carpio, C. macropomum e cross-bred tambacu. The incidence of this parasite was elevated in the summer for L. macrocephalus, spring for P. mesopotamicus and C. macropomum, and both seasons for cross-bred tambacu. Lernaea cyprinacea copepodes were observed in L. macrocephalus, P. mesopotamicus, C. carpio and cross- breeding tambacu, in spite of the fact that C. carpio has demonstrated high parasitism of adult form. The fish L. macrocephalus, P. mesopotamicus and C. carpio were sponged intensely by Dolops carvalhoi, in situation of high population density. Piaractus mesopotamicus was considered the species more parasited by myxosporídeos, that were also observed in L. macrocephalus and cross-breeding tambacu.

Animals↗
PubMed2006

The evolution of parasites in response to tolerance in their hosts: the good, the bad, and apparent commensalism.

Tolerance to parasites reduces the harm that infection causes the host (virulence). Here we investigate the evolution of parasites in response to host tolerance. We show that parasites may evolve either higher or lower within-host growth rates depending on the nature of the tolerance mechanism. If tolerance reduces virulence by a constant factor, the parasite is always selected to increase its growth rate. Alternatively, if tolerance reduces virulence in a nonlinear manner such that it is less effective at reducing the damage caused by higher growth rates, this may select for faster or slower replicating parasites. If the host is able to completely tolerate pathogen damage up to a certain replication rate, this may result in apparent commensalism, whereby infection causes no apparent virulence but the original evolution of tolerance has been costly. Tolerance tends to increase disease prevalence and may therefore lead to more, rather than less, disease-induced mortality. If the parasite is selected, even a highly efficient tolerance mechanism may result in more individuals in total dying from disease. However, the evolution of tolerance often, although not always, reduces the individual risk of dying from infection.

Animals↗
PubMed2006

[Social determinants, feeding practices and nutritional consequences of intestinal parasitism in young children].

INTRODUCTION: Studies on intestinal intestinal parasitism in children under 2 years of age have rarely been performed. The nutritional consequences and feasibility of parasite prevention justify the current study. OBJECTIVES: The study was undertaken with 3 goals: (1) to identify the prevalence of pathogenic intestinal parasites (PIP), (2) to determine the social factors, sanitary conditions and nutritional practices that predict PIP, and (3) to evaluate PIP effects on infant nutritional status. MATERIALS AND METHODS: All mothers with children under 18 months of age and living in an urban community of coastal Colombia were invited to participate in the PIP study. A fecal sample was obtained from each of 136 children; they represented 62% of the total 7-18 month-old population in the community. Presence of intestinal parasites was identified by direct microscopy and confirmed by a concentration test (Ritchie-Frick procedure). Logistic regressions were used to predict presence of PIP. The Z scores of length-for-age (< -2 SD-chronic malnutrition) and weight-for-length (< -2 SD-acute malnutrition) and covariance analysis were done to detect associations between intestinal parasitism and nutritional status. RESULTS: Of the 136 children, 30.6% were infected; 26.2% had helminth infections (A. lumbricoides, T. trichiura, S. stercoralis), 14.9% had protozoan infections (G. lamblia) and 11.8% had mixed infections. Wasting and stunting were present in 2.9% and 12.5%, respectively. Lack of sanitary toilet facilities and low maternal education were related to mixed infections and presence of helminths (p < 0.05). Weaned children were at greater risk of mixed infections (Odds Ratio (OR) 6.5; 90% CI: 1.9-21.5) and of G. lamblia infections (OR: 2.89; 90% CI: 1.0-8.34). Children infected with T. trichiura and with mixed infections were more likely to show wasting (p < 0.05). CONCLUSION: The high infections in young children indicate that they be included in periodic antiparasitic chemotherapy. Burden of disease associated to intestinal parasitism may be reduced if breastfeeding is continued beyond 6 months of age.

Animals↗
PubMed2006

[Incidence of intestinal parasites among primary school children in Malatya].

The aim of this study was to determine the incidence of intestinal parasites among primary school children in the central region of Malatya and to educate the children about parasitic diseases. During the study, cellophane tape preparations and stool samples that had been prepared using direct mounting methods were examined. In addition the students were informed about intestinal parasites. Parasitic infection was observed in 415 (22.5%) out of 1838 students and the highest rate of 10.6% was that of Enterobius vermicularis. The rates of Giardia intestinalis, Entamoeba coli, Blastocystis hominis, Taenia sp., Hymenolepis nana, Trichomonas hominis, Ascaris lumbricoides and Iodamoeba butschlii were found to be 8.5%, 1.9%, 1.4%, 0.3%, 0.1%, 0.1%, 0.05%, and 0.05%, respectively. Thus, intestinal parasites are important among primary school children in Malatya and it seems that there is a relationship between socioeconomic conditions and the rate of intestinal parasites.

Animals↗