Fishborne zoonotic intestinal trematodes, Vietnam

Although fishborne zoonotic trematodes that infect the liver are well documented in Vietnam, intestinal fishborne zoonotic trematodes are unreported. Recent discoveries of the metacercarial stage of these flukes in wild and farmed fish prompted an assessment of their risk to a community that eats raw fish. A fecal survey of 615 persons showed a trematode egg prevalence of 64.9%. Infected persons were treated to expel liver and intestinal parasites for specific identification. The liver trematode Clonorchis sinensis was recovered from 51.5%, but > or =1 of 4 intestinal species of the family Heterophyidae was recovered from 100%. The most numerous were Haplorchis spp. (90.4% of all worms recovered). These results demonstrate that fishborne intestinal parasites are an unrecognized food safety risk in a country whose people have a strong tradition of eating raw fish.     

Freshwater aquaculture nurseries and infection of fish with zoonotic trematodes, Vietnam

Residents of the Red River Delta region of northern Vietnam have a long tradition of eating raw fish. Fish-borne zoonotic trematodes (FZTs) are estimated to infect ≈1 million persons in Vietnam. It remains uncertain at what stages in the aquaculture production cycle fish become infected with FZTs. Newly hatched fish (fry) from 8 hatcheries and juveniles from 27 nurseries were therefore examined for FZT infection. No FZTs were found in fry from hatcheries. In nurseries, FZT prevalence in juveniles was 14.1%, 48.6%, and 57.8% after 1 week, 4 weeks, and when overwintered in ponds, respectively. FZT prevalence was higher in grass carp (p<0.001) than in other carp species. Results show that nurseries are hot spots for FZT infections in fish. Thus, sustainable FZT prevention strategies must address aquaculture management practices, particularly in nurseries, to minimize the risk of distributing infected juveniles to grow-out ponds and, subsequently, to markets for human consumption.     

Animal Reservoir Hosts and Fish-borne Zoonotic Trematode Infections on Fish Farms, Vietnam

Fish-borne zoonotic trematodes (FZT) pose a risk to human food safety and health and may cause substantial economic losses in the aquaculture industry. In Nghe An Province, Vietnam, low prevalence of FZT for fish farmers but high prevalence for fish indicate that reservoir hosts other than humans may play a role in sustaining transmission. To determine whether domestic animals may be reservoir hosts, we assessed prevalence and species composition of FZT infections in dogs, cats, and pigs in a fish-farming community in Vietnam. Feces from 35 cats, 80 dogs, and 114 pigs contained small trematode eggs at 48.6%, 35.0%, and 14.4%, respectively; 7 species of adult FZT were recovered from these hosts. These results, combined with data from previous investigations in this community, imply that domestic animals serve as reservoir hosts for FZT and therefore must be included in any control programs to prevent FZT infection in humans.     

Overview of food- and water-borne zoonotic parasites at the farm level

Zoonotic parasites found in food animals include a wide variety of protozoa, nematodes, trematodes, and cestodes. Many of these parasites are emerging or already occur globally due to changes in farming practices and the increased movement of animals, food, and people. Some of the emerging or ubiquitous parasites, including Toxoplasma, Cryptosporidium, Trichinella, and Taenia, present enormous risks to global food production and consumer health. The parasite life cycle stages, such as eggs, oocysts, and cysts, typically resist adverse temperatures, desiccation, natural irradiation, chemicals, and disinfectants that are commonly used for controlling bacteria and viruses. Other important parasites include trematodes such as Clonorchis and Paragonimus, which are transmitted via fish or crustaceans and cause serious human disease in specific regions of the world. The potential for global occurrence of these parasites is increasing. Control of zoonotic parasites at the producer level requires education and the development and implementation of effective measures to eliminate the contamination of agricultural water and feed with viable stages of parasites. Standardisation, implementation, and documentation of control measures should increase confidence in global food trade.     

Raw-fish-eating behavior and fishborne zoonotic trematode infection in people of northern Vietnam

Raw fish consumption in restaurants, for example, Sashimi style, is popular worldwide. In Vietnam, raw fish dishes are also traditionally prepared and consumed in private households. However, the habits of eating raw or otherwise inadequately cooked fish can be associated with risks of acquiring fishborne zoonotic trematode (FZT) infection. The present study was done in a fish-farming community in Nam Dinh, Vietnam, to obtain information about habits of eating raw fish dishes and risks for human FZT infection. Discussions were held in different groups divided by gender and age on raw-fish-eating behavior. A total of 180 household members were interviewed and their stool samples analyzed to identify risk factors of FZT infection. There was awareness about the risk of liver fluke infections from eating raw fish. However, many older people accepted these risks and continued eating raw fish, as they know effective drug treatment is available. Raw fish dishes are consumed at social gatherings from shared plates and dipping sauces using the same chop sticks. This is likely to pose risks of crosscontamination with FZT metacercariae to different food items as indicated by the finding that 25.8% of household members that stated not to have eaten raw fish were infected. In total, 32.2% fish farm household members were infected with FZT. The odds of FZT infection was 2.3 times higher (p?=?0.013) for those eating raw fish than for those who did not eat raw fish. Among the people eating raw fish, those eating raw fish in restaurants had 3.6 times higher odds of FZT infection (p?=?0.009) than people eating raw fish at home. A successful program to control FZT must be based on in-depth knowledge on the social and anthropological determinants of people's raw-fish-eating behavior and hygiene practices as well as production of FZT-free fish for human consumption.     

DNA barcoding of Iranian radicine freshwater snails begins to untangle the taxonomy and phylogeography of intermediate hosts of schistosomiasis and fasciolosis from the Middle East and across Central Asia

In the Middle East radicine snails are of considerable medical and veterinary importance acting as vectors of trematodes. In Iran, such snails are responsible for the transmission of the zoonotic trematodes Schistosoma turkestanicum and Fasciola gigantica. Historically, Radix gedrosiana has been incriminated as an important intermediate host for both trematodes, however, controversy remains over the snail’s true taxonomic status. This species has been determined using morphological characters that has resulted in erroneous identification of species, affecting understanding of population biology, and ultimately affecting vector incrimination. In this current study DNA barcoding using cox1 and phylogenetic analyses revealed that snails identified as R. gedrosiana from Iran split into two separate species, Radix euphratica and Ampullaceana sp. The cox1 also provided useful insights into the evolutionary history of R. euphratica populations. Phylogeographic analyses indicated that R. euphratica had an Iraqi/Iranian origin approximately 3.3 MYA and exists as a large stable population across the Middle East and Central Asia, and a lack of genetic differentiation between geographical isolates. Such molecular barcoding techniques are crucial for the identification of radicine snails of Iran being invaluable for the monitoring of zoonotic flukes, understanding the distribution of infection and the accurate incrimination of snail vectors.     

Two New Trematodes of Family Acanthocolpidae Luhe, 1906 From Marine Fish Leiognathus daura (Cuvier) from the Coast of Puri,Orissa, India

Background

Genus Acanthocolpus (Trematoda: Acanthocolpiidae) is one of the most important zoonotic digenean with wide geographic distribution in the world. The purpose of the present study was to describe morphological and morphometrical characteristics of Acanthocolpus species, currently prevalent in marine fish fauna of Puri coast, Orissa, India.

Methods

Gastro-intestinal organs of Leiognathus daura (Cuvier) in Puri coast, Orissa, India, were examined for infectivity with digenean trematode species. For examination and measurements of helminthes, acetoalum carmine staining was performed, followed by camera Lucida drawings of morphological characters and measurements of morphometrical criteria with a calibrated microscope. Using valid trematode systematic keys, almost all the parasites were identified at the level of species.

Results

Overall, 36 marine fishes were found infected with at least one species of Acanthocolpus. Considering morphological characteristics of Acanthocolpus, two species were identified as new species including Acanthocolpus durghai sp.nov. and Acanthocolpus amrawatai sp.nov.

Conclusion

During the survey of helminth parasites, collected six different species of the genus Acanthocolpus, out of these two are new species, another is redescribed to show certain variation, the new parasite was obtain from the intestine of marine fish Leiognathus daura (Cuvier)     

Assessment of environmental stressors potentially responsible for malformations in North American anuran amphibians

Several species of anuran amphibians from different regions across North America have recently exhibited an increased occurrence of malformations, predominantly of the hindlimb. Research concerning the potential causes of these malformations has focused extensively on three stressors: chemical contaminants, ultraviolet (UV) radiation, and parasitic trematodes. In this overview of recent work with each of these stressors, we assess their plausibility as contributors to the malformations observed in field-collected amphibians. There is as yet little evidence that chemical contaminants are responsible for the limb malformations. This includes chemicals, such as the pesticide methoprene, that could affect retinoid-signaling pathways that are critical to limb development. Exposure to UV radiation also seems to be an unlikely explanation for hindlimb malformations in amphibians. Although solar UV can cause hindlimb deficiencies in amphibians, a probabilistic assessment based on empirical dose-response and exposure data indicates that UV exposures sufficient to induce limb defects would be uncommon in most wetlands. Results of controlled studies conducted with some affected species and field-monitoring work suggest infection by digenetic trematodes as a promising explanation for the malformations observed in anurans collected from many field sites. Controlled experimentation with additional species and monitoring across a broader range of affected sites are required to assess fully the role of trematodes in relation to other stressors in causing limb malformations. If trematode infestations are indeed related to the recent increases in malformed amphibians, then the question remains as to what alterations in the environment might be causing changes in the distribution and abundance of the parasites.     

Fasciolopsis buski Detected in Humans in Bihar and Pigs in Assam,India

The foodborne intestinal trematode Fasciolopsis buski causes the neglected zoonotic disease fasciolopsiasis. We detected F. buski infection in 14 pediatric patients in Sitamarhi, Bihar, and in pigs in Sivasagar, Assam, India. Proper diagnostic methods and surveillance are urgently needed to accurately estimate the true burden of this disease in India.     

Parasitic factor and cancer

There is opinion in the literature as to that liver trematode infections, such as opisthorchiasis, clonorchiasis, fascioliasis, and metorchiasis, can induce cancer of the liver pancreas, intestine - this all is clinically observed. The authors were the first in world practice to show the development of a hepatic blastomatous process in animals (albino rats, cats) with opisthorchiasis in 13%; cancer developed in 28 and 56% with the use of a hepatotropic carcinogen and combined (opisthorchiasis + a carcinogen) exposure, respectively. Throughout his life, a human being can easily catch these trematodes that have carcinogenic activity and these diseases concurrent with household and food carcinogens can give rise to tumors in the liver pancreas and intestine. Timely diagnosis and specific anthelmintic therapy are necessary to prevent parasitic cancer.     

The complete mitochondrial genome of Metorchis orientalis (Trematoda: Opisthorchiidae): Comparison with other closely related species and phylogenetic implications

Metorchis orientalis (Trematoda: Opisthorchiidae) is an important trematode infecting many animals and humans, causing metorchiasis. In the present study, the complete mitochondrial (mt) genome of M. orientalis was sequenced. The complete mt genome of M. orientalis is 13,834 bp circular DNA molecule and contains 12 protein-coding genes, 22 transfer RNA genes, and two ribosomal RNA genes. The gene content and arrangement of M. orientalis is the same as those of Opisthorchiidae trematodes (Opisthorchis viverrini, Opisthorchis felineus and Clonorchis sinensis), but distinct from Schistosoma spp. Phylogenetic analyses using concatenated amino acid sequences of 12 protein-coding genes with three different computational algorithms (Bayesian inference, maximum likelihood and maximum parsimony) revealed that M. orientalis and O. viverrini represent sister taxa. The mt genome provides a novel genetic marker for further studies of the identification, classification and molecular epidemiology of Opisthorchiidae trematodes, and should have implications for the diagnosis, prevention and control of metorchiasis in animals and humans.     

Contaminant effects on host-parasite interactions: atrazine, frogs, and trematodes

The effects of contaminants on multispecies interactions can be difficult to predict. The herbicide atrazine is commonly used in North America for corn crops, runs off into wetlands, and has been implicated in the increasing susceptibility of larval frogs to trematode parasites. Using experimental challenges with free-living stages of trematodes (cercariae), it was found that Rana sylvatica tadpoles exposed to 30 microg/L of atrazine had significantly higher intensity of parasitism than did larval frogs either not exposed or exposed to 3 microg/L of atrazine. This result could not be explained by high concentrations of atrazine diminishing antiparasite behavior of tadpoles. Furthermore, when tadpoles and cercariae both were exposed to the same concentration of atrazine, either 3 or 30 microg/L, the abundance of formed cysts was not different from the condition in which both were housed at 0 microg/L of atrazine. Atrazine appears to be debilitating to both free-living cercariae and tadpoles. Studies examining relations between parasitism and contaminant levels must account for such combined effects as well as influences on other interacting species (e.g., first intermediate snail hosts).     

Seasonal and Geographic Distribution of Cercarial Infection in Lymnaea gedrosiana (Pulmunata: Lymnaeidae) In North West Iran

Background

Trematodes are a diverse group of endoparasites which require molluscan and vertebrate animals as intermediate and definitive hosts in their life cycle. The present study was carried out to determine the diversity and geographic distribution of infection with trematodes''cercariae in the snail Lymnaea gedrosiana from north-west Iran.

Methods

A total number of 6759 Lymnaeidae snails were collected from 28 snail habitats; of these L. gedrosiana was the prevalent snail (74.37%) which examined for cercarial infection by shedding method.

Results

The overall infection rate was 8.03%. The most frequent trematodes cercariae in the snail were xiphidiocercariae (81.98%), furcocercariae (32.26%), echinostome cercariae (5.19%), and monostome cercariae (1.24%). The highest infection rate in L. gedrosiana (100%) was with echinostome cercariae from Golestaneh in autumn.

Conclusion

Due to the important role of pond snails in transmission of cercariae to fish as a source of zoonotic diseases, it is essential to estimate the distribution and abundance of the snails and the rate of their infection with different trematodes’ cercariae, and establish control programs in each region.     

深圳市35间普惠式托幼机构膳食调查分析

目的 对深圳市托幼机构膳食结构进行调查分析。方法 采取整群抽样的方法,以深圳市某辖区内35间普惠式幼儿园作为研究对象,分析学龄前儿童在园膳食情况。结果 35间幼儿园食物构成合理,各类食物平均每日供应总量为754.3（±55.37）g,大豆及豆制品供应不足,水果、鱼虾类、奶类及食用油供应水平低下水平,而畜禽肉类超量供应;不同级别托幼机构学龄前儿童各类食物每日人均摄入量及总量差异均有统计学意义（P＜0.05）;日均摄入能量合计为（979.82±96.06） kcal,占RNI或AI的75.37%;蛋白质和碳水化合物供能构成比较高,脂肪供能比例合理。结论 深圳市辖区内35所普惠式托幼机构膳食结构不甚合理,三大产能营养素提供的总热量仍显不足,供能比例不平衡,提高膳食管理制度运行质量可改善现状。     

Impairments of memory and learning in older adults exposed to polychlorinated biphenyls via consumption of Great Lakes fish.

An association between in utero polychlorinated biphenyl (PCB) exposure and impaired childhood intellectual functioning has been reported, but the potential impact of PCB exposure during adulthood on intellectual functioning has received little attention. We assessed the impact of PCBs and other fish-borne contaminants on intellectual functioning in older adults. The subjects were 49- to 86-year-old Michigan residents recruited from an existing cohort. Fish eaters ate > 24 lb of sport-caught Lake Michigan fish per year and non-fish eaters ate < 6 lb of Lake Michigan fish per year. A battery of cognitive tests including tests of memory and learning, executive function, and visual-spatial function was administered to 180 subjects (101 fish eaters and 79 non-fish eaters). Blood samples were analyzed for PCBs and 10 other contaminants. We evaluated cognitive outcomes using multiple regression. PCBs and dichlorodiphenyl dichloroethene (DDE) were markedly elevated in fish eaters. After controlling for potential confounders PCB, but not DDE, exposure was associated with lower scores on several measures of memory and learning. These included the Weschler Memory Scale verbal delayed recall (p = 0.001), the semantic cluster ratio (p = 0.006), and list A, trial 1 (p = 0.037), from the California Verbal Learning Test. In contrast, executive and visual-spatial function were not impaired by exposure to either PCBs or DDE. In conclusion, PCB exposure during adulthood was associated with impairments in memory and learning, whereas executive and visual-spatial function were unaffected. These results are consistent with previous research showing an association between in utero PCB exposure and impairments of memory during infancy and childhood.     

Possible human health hazards from outbreak of epizootic ulcerative syndrome (EUS) in fish in the Asia-Pacific region.

Acid fast rods, constituting chemoautotrophic nocardioform bacteria, could be repeatedly cultivated and isolated and propagated indefinitely in vitro from fish actinomycotic macrophage granuloma from the massive epizootics of ulcerative disease syndrome of fish in eastern India during 1988-90. The possible human hazards of zoonotic actinomycotic infections as a result of handling and consumption of such fish are assessed.     

青岛市崂山区托幼机构2004-2011年儿童健康体检结果分析

目的为了解青岛市崂山区托幼机构儿童健康状况动态变化,以便进一步加强和改进托幼机构卫生保健工作。方法收集2004-2011年托幼机构春季儿童体检资料,并对其进行分析。结果 8年来青岛市崂山区托幼机构儿童的低体重儿童检出率呈下降趋势,儿童肥胖检出率及视力异常检出率呈上升趋势,而贫血儿童检出率及龋齿儿童检出率呈下降趋势,经趋势χ2检验,有统计学意义（P〈0.01）。结论应加强托幼机构儿童健康管理,龋齿、肥胖、贫血和视力异常的儿童是干预重点。     

Perceptions of health risks and benefits associated with fish consumption among Russian consumers

Knowledge about differences in consumer perceptions of health risks and benefits related to fish consumption is important for the development of targeted health interventions associated with dietary choice. The purpose of this study is to identify individual differences in Russian consumers according to their perceptions of health risks and benefits associated with fish consumption. By application of a cluster analysis on perceptions of personal risks and benefits associated with the consumption of fish, four groups of Russian consumers were classified as: very positive; positive; moderately positive; and 'high risk-high benefit' about the healthiness of fish consumption. Differences in perceptions of personal risks and benefits across consumers were related to self-reported fish consumption, optimism about personal risks and benefits, and optimism about personal knowledge about risks and benefits. Implications for the development of targeted health interventions to influence perceptions of risks and benefits associated with fish consumption, and ultimately fish consumption, are discussed. It is concluded that optimism regarding perceptions and knowledge of health risks, and health benefits should be taken into account when developing interventions aimed at consumer health.     

2011至2013年无锡市学龄前儿童主要常见病患病情况分析

目的：掌握无锡市学龄前儿童健康状况及变化趋势,为卫生行政部门制定学龄前儿童常见病管理方案提供科学依据。方法收集、整理、分析2011至2013年无锡市托幼机构卫生保健工作统计年报表。结果3年间肥胖、营养不良、龋齿和视力不良患病率均有逐年上升趋势,均有统计学意义（χ2值分别为68．851、99．600、14．774和100．218,均P＜0．05）。儿童的常见病患病情况在不同地区、不同性质和不同类别的托幼机构均有统计学意义,贫血患病率：农村高于城市（χ2＝1494．640,P＜0．001）,民办园高于公办园（χ2＝15．847,P＜0．05）,省优质园高于市优质园和合格园（χ2＝35．542,P＜0．001）;肥胖患病率：城市高于农村（χ2＝1525．640,P＜0．001）,民办园高于公办园（χ2＝19．082,P＜0．05）,省优质园高于市优质园和合格园（χ2＝120．063,P＜0．001）;营养不良患病率：农村高于城市（χ2＝4．820,P＜0．05）,民办园高于公办园（χ2＝186．998,P＜0．001）,合格园高于省优质园和市优质园（χ2＝123．046,P＜0．001）;龋患率：城市高于农村（χ2＝7．220,P＜0．05）,民办园高于公办园（χ2＝106．106,P＜0．001）,合格园高于省优质园和市优质园（χ2＝76．578,P＜0．001）;视力不良率：城市高于农村（χ2＝12．188,P＜0．05）,公办园高于民办园（χ2＝82．549,P＜0．001）,省优质园高于市优质园和合格园（χ2＝163．709,P＜0．001）。结论视力不良、龋齿和肥胖是无锡市托幼机构儿童的主要健康问题,今后要进一步加强对学龄前儿童常见病的干预,保障儿童的身心健康。