Fasciola Eggs Research Articles

Potential use of Mucor circinelloides for the biological control of certain helminths affecting livestock reared in a care farm

A preliminary study to evaluate the possibilities of biological control procedures against parasites affecting livestock reared in a care farm has been conducted. Adults with mental disabilities were involved in spreading the spores of the filamentous fungus Mucor circinelloides directly onto the faeces, or as a food additive. In the first assay, the spores were sprayed directly onto the faeces of piglets and calves parasitised by roundworms (Ascaris suum) and liver flukes (Fasciola hepatica), respectively. In the second assay, the spores were mixed with on-farm mash feed. Participation of the adults in the experiments was fully satisfactory. In the manure sprayed Mucor spores, the viability of eggs of roundworms and flukes reduced by 53% and 74%, respectively. Significant reductions of viability of eggs of Ascaris (60%) and Fasciola (67%) in the faeces of piglets and calves given mash feed-added Mucor spores were achieved, which demonstrates their ability to survive in the digestive tract of the animals. It is concluded that biological control of parasites could be helpful to decrease the risk of infection in animals reared by intellectually disabled adults in a care farm, and it could motivate them to accomplish new tasks.

Liver fluke (Fasciola hepatica) naturally infecting introduced European brown hare (Lepus europaeus) in northern Patagonia: phenotype, prevalence and potential risk.

Fascioliasis has recently been included in the WHO list of Neglected Zoonotic Diseases. Besides being a major veterinary health problem, fascioliasis has large underdeveloping effects on the human communities affected. Though scarcely considered in fascioliasis epidemiology, it is well recognized that both native and introduced wildlife species may play a significant role as reservoirs of the disease. The objectives are to study the morphological characteristics of Fasciola hepatica adults and eggs in a population of Lepus europaeus, to assess liver fluke prevalence, and to analyze the potential reservoir role of the European brown hare in northern Patagonia, Argentina, where fascioliasis is endemic. Measures of F. hepatica found in L. europaeus from northern Patagonia demonstrate that the liver fluke is able to fully develop in wild hares and to shed normal eggs through their faeces. Egg shedding to the environment is close to the lower limit obtained for pigs, a domestic animal whose epidemiological importance in endemic areas has already been highlighted. The former, combined with the high prevalence found (14.28%), suggest an even more important role in the transmission cycle than previously considered. The results obtained do not only remark the extraordinary plasticity and adaptability of this trematode species to different host species, but also highlight the role of the European brown hare, and other NIS, as reservoirs capable for parasite spillback to domestic and native cycle, representing a potentially important, but hitherto neglected, cause of disease emergence.

Effect of nitroxynil (fasciolid) on adult Fasciola gigantica and Fasciola hepatica in infected cows

Background Drug resistance to treatment of fascioliasis with triclabendazole (TCBZ) has emerged in Sohag Governorate, Egypt. Nitroxynil belongs to the halogenated phenol group of fasciolicides. It is highly active against adult liver flukes. A nitroxynil metabolite is produced in the liver parenchyma adding to its flukicidal activity and augmenting its efficacy against late immature flukes that migrate through the liver tissues. Treatment with nitroxynil may be an effective replacement for therapy with TCBZ in cases of resistance. Objective The aim of this study was to evaluate the efficacy of nitroxynil in the treatment of fascioliasis by assessing its effect on teguments and durability of adult Fasciola gigantica and Fasciola hepatica worms. Materials and methods Infected cows were selected on the basis of clinical signs, and infection was confirmed by detection of Fasciola eggs in their stools. Nitroxynil was administered as recommended in two doses 15 days apart, and the animals were slaughtered 15 days after treatment. Fasciola worms collected from the bile ducts were identified and prepared for electron microscopy. Tegument changes were examined with scanning electron microscopy. Results The removed adult flukes of both species were moving sluggishly and appeared pale with no evidence of gut content. Scanning electron microscopy examination of these flukes revealed evidence of swelling of the tegument that showed regional variation in its severity. Loss of spines was also observed. Conclusion The present study demonstrated the flukicidal properties of nitroxynil, proving that the tegument is an important target for its action. Disruption of the fluke's main line of defense allowed the drug access to other internal tissues, leading to more widespread damage. Nitroxynil may be successfully used for treatment in case of resistance to TCBZ.

Effects of Experimental Fasciola Gigantica Infection on Serum Testosterone Profiles and their Relationship with Semen Characteristics of Yankasa Ram

This study was designed to evaluate the effects of Fasciolosis on serum testosterone profiles and semen characteristics of Yankasa rams. Twelve, apparently healthy, Yankasa rams aged 18-24 months were randomly divided into two groups (infected group A and control group B) with seven and five rams, respectively. The rams werekept under intensive management in different pens throughout the study period. Group A rams were inoculated with 800 metacecariae orally and monitored for 12 weeks Post Infection (PI). Clinical signs were manifested 2 weeks PI. Faecal examination revealed Fasciola eggs at week 7 PI in group A. Three mL of blood were collected aseptically via the jugular vein at 30 min interval, weekly between 08:00-9:00am for serum testosterone assay. Testosterone assay was done using ELISA technique. There was significant decrease in testosterone concentration in group A at different time intervals of the weeks of post-infection. The semen analysis showed the lowest mean (±SEM) of semen volume, semen motility, semen concentration, of group A, as (0.01±0.0 mL), (3.6±2.4%), (16.1±4.2%) compared to group B with mean (±SEM) (1.6±0.1 mL), (93.0±1.2%), (440.0±13.0%) at week 7 post- infection, respectively. This study revealed that Fasciolosis has a great impact on sheep mainly by diminishing their reproductive efficiency and rendering infected rams infertile. It is concluded that F. gigantica infectionhad advanced effects on testosterone production and semen quality of Yankasa rams.

Diagnosis of Fasciola infection by SDS–PAGE eluted excretory secretory (ES) protein fractions using dot-ELISA

Fascioliasis is now recognized as an emerging zoonotic disease in Egypt. Diagnosis in suspected patients still needs some degree of accuracy. In the present study, three Fasciola gigantica execratory secretory (ES) protein bands of molecular weight (MW) ranging from 14 to 20kDa, 25 to 32kDa and 45 to 65kDa were eluted after fractionation of the parasite antigen using SDS–PAGE. The extracted kDa protein bands were concentrated and evaluated in diagnosis of Fasciola infection. Moreover the level of their cross reaction with other parasitic infections in infected and suspected patients of known parasite eggs/gram stool was evaluated using the dot-ELISA technique. Protein bands in the range of 14–20kDa and that of 25–32kDa were markedly specific and sensitive in diagnosis of different levels of anti-Fasciola antibodies (Ab) in sera of infected cases. These two groups of bands were able to exclude cross-reaction between anti-Fasciola Ab and other parasites recorded in stool of selected patients suffering from Schistosoma mansoni, Ascaris, and Giardia, either in single or mixed conditions with Fasciola eggs. While that of 45–65kDa appeared less specific than the other previously mentioned bands. Protein bands in the range of 25–32kDa appeared more sensitive than the other protein bands in detection of anti-Fasciola Ab at higher serum dilutions. The Dot-ELISA technique was proved to be more economic and easy in application. The dotted very small amount of antigens can be stored in a freezer and used at request in diagnosis of large numbers of samples.

Contributions on human fascioliasis and its snail intermediate host in Nile Delta, Egypt

The present study spotted some light on human fascioliasis in Kafr El-Sheikh Governorate in the west of the Nile Delta in Egypt, its species, its intermediate host (IMH) snail and tried to answer previous questions about development of Fasciola (F.) species in new snail hosts other than that known for animal fascioliasis in Egypt. The study recorded a percentage of infection by Fasciola eggs reached up to 6.02% in 1810 randomly collected human stool samples from 6 climatically selected sites in this governorate using fluke-finder technique. The incidence was high in Sedi Salem and Motobus than in the other study sites. Micrometry measuring of 100 eggs from each locality showed that egg size cannot be used as a main criterion in differentiation between F. hepatica and gigantica. Wide range of egg size varied between 130-162.5 µ X 75-87.5 µ with a mean length and width of 144.24 ± 11.33 µ X 80± 6.55µ, was recorded. Upon dissection of 1972 Lymnaea (L.) cailliaudi, 268 L. alexandrina, 502 Bulinus species, 11316 Biomphalaria alexandrina, 1398 Cleopatra species, 8520 Physa acuta, 420 Melania tuberculata, 2132 Vivipara (Bellamya) unicolar, 144 Neritina nilotica and 1570 Planorbis philippi, Fasciola parthenitae were not detected in snails other than L. cailliaudi (the known IMH of Fasciola in Egypt). The results proved that there is no accommodation has occurred in any of the surrounding snails to transmit Fasciola to man. The present study proved that human fascioliasis in the study sites was due to Fasciola gigantica not F. hepatica. This appeared in its tendency to develop in L. cailliaudi not in other tested snails with successive radial generations as that described previously for F. gigantica. Moreover, early mature flukes extracted from laboratory infected rabbits by the produced encysted metacercariae had the characteristic features described previously for F. gigantica.

The transmission of Fasciola spp. to cattle and contamination of grazing areas with Fasciola eggs in the Red River Delta region of Vietnam

At four times during November 2010, cattle with infections of Fasciola spp., in two communes of northern Vietnam, were allocated to two equivalent groups. Cattle in one group were treated with triclabendazole. Faecal samples collected monthly from both groups were tested for Fasciola copro-antigens and the presence of Fasciola eggs. Re-infection of treated cattle occurred from early March to late November, coinciding with high weekly totals of rainfall. Contamination of grazing areas by untreated cattle was high and relatively constant throughout the year. However, contamination was reduced to undetectable amounts for 8 to 12 weeks after treatment and even at 20 weeks was only 50% or less of the pre-treatment amounts. Therefore, treatments given in mid-September and again in early April, at the start of the wet season, may be sufficient to prevent contamination of grazing areas and reduce the prevalence and severity of Fasciola infections in cattle.

Vasculitis secundaria a infección por Fasciola hepática

There is a case of a 38 year-old male patient coming from an area where hepatic fascioliasis is endemic in Peru. He was hospitalized because he showed 4 weeks of symptoms like fever, intense myalgias, erythematous and painful injuries on limb extensions. The electromyography and nerve conduction velocity showed a global inflammatory myopathy. A skin biopsy showed polyarteritis nodosa-type vasculitis. During the evaluation process prior to the immunosuppressive therapy, hepatic Fasciola eggs were found in the parasitological examination of stools. The fascioliasis diagnosis was confirmed by fas2-ELISA: 0.46 (VN <0.20). Clinical symptoms started to subside after treatment with ticlabendazol. Contact with the patient was maintained for a year and there was no evidence of disease recurrence, and he was asymptomatic.

Study on the prevalence of bovine <i>fasciolosis</i> in and around Bahir Dar, Ethiopia

A cross sectional study aimed at determining the prevalence and type of common Fasciola species in cattle was conducted in and around Bahir Dar from November 2008- March 2009. The study was based on post-mortem inspection of livers of slaughtered animals at Bahir Dar municipality abattoir and coprological examination using sedimentation technique on fecal samples collected from animals of Bahir Dar and surrounding areas. Out of 413 livers inspected, 165 (39.95%) were positive for Fasciola species. F. hepatica was found to be the most prevalent species in cattle of the study area (89.70%). About 3.63% were positive for F. gigantica and 6.67% were harboring mixed infections. Likewise, out of 384 fecal samples examined 141 (36.72) were positive for the presence of Fasciola eggs. Risk factors such as locality, body condition and sex didn’t show any effect on the prevalence of infections (P>0.05). However, breed and age group revealed significant disparity (P<0.05) as greater magnitude of infections were detected in exotic breed and young age group, respectively. In view of the current result, fasciolosis could be considered as a major problem in Bahir Dar and surrounding areas as the ecological factors and management conditions are suitable both for the snail intermediate host and the parasite to be maintained. Strategic treatments need to be implemented at appropriate timing with the aim of reducing worm burden from infected animals and preclude pasture contamination. Integrated control approaches involving livestock owners has to be implemented in reducing the population and activity of snail intermediate hosts to enable maximization of long-term returns from such endemic areas.Key words: Abattoir, Bovine, Bahir Dar, Coprology, Fasciola, Prevalence.

Effect of sodium hypochlorite on Fasciola gigantica eggs and the intermediate host, Lymnaea natalensis: A scanning electron microscopy study

The liver fluke Fasciola is one of the commonest causative agents of liver disease in the world. Infection with this organism is of veterinary and medical importance, particularly in areas of high-density cattle and sheep production. Sodium hypochlorite (NaOCl) has been suggested for use in the control of Fasciola transmission. The current study was designed to evaluate the effect of NaOCl on the eggs and their intermediate hosts (Lymnaea natalensis snails) by scanning electron microscopy. Exposure of eggs to NaOCl had markedly deleterious effects on the whole body surface, from smooth to oedematous and disrupted, and on their integrity. These effects were concentration-dependent. Treatment of the intermediate host with various concentrations of NaOCl increased the mortality rate, and the effect was also dependent on concentration and length of exposure. Scanning electron microscopy of the snail foot region showed extensive alterations of the surface, with damage in some areas, after treatment with 10ppm NaOCl for 15min. Sodium hypochlorite may therefore be a useful control measure for eliminating both Fasciola eggs and the intermediate snail host.

Interrelationship between Fasciola Eggs Count, Haematological Parameters, Liver and Testicular Pathology of Yankasa Rams Experimentally Infected with Fasciola Gigantica in Zaria, Nigeria.

The study was designed to determine the influence of F. gigantica and fasciola eggs on haematological parameters, liver and testicular damage in Yankasa rams experimentally infected with F. gigantica. The experimental rams were randomly assigned into (n=7) infected group and (n=5) control group. Pre-infection data were collected in both groups for 4 weeks, 5 ml of blood were aseptically collected for evaluation of haematological parameters and total protein levels. The haematological parameters prior to experimental infection were within the normal range. The infected group were orally inoculated with 800 metacercariae and monitored for 2 weeks post infection (PI) for manifestation of clinical signs. The infected rams had significant p>0.05 decreased in packed cell volume (PCV) 33.6±1.8 %, red blood cells (RBC) 4.8 ± 0.4 x106/ml, haemoglobin concentration (Hb) 11.4±0.6 g/dl, white blood cells (WBC) 6.8±0.3 x103/ml. Compared to the control rams that had (PCV) 40.4±2.2 %, (RBC) 6.9± 0.2 x106 /ml, (Hb) 13.8±0.8 g/dl, and (WBC) 5.8±0.2 x103/ml at the end of the study 12 weeks PI. The cumulative mean of total protein (5.49±0.3 g/dl) levels of the infected rams had significant p>0.05 difference compared to total protein (6.56±0.4 g/dl) levels the control rams. There was no significant difference in the differential leucocyte count of both groups. The fasciola eggs and flukes recovered from the bile and liver tissue of the infected rams was 1850.0±650.0 and 550.0±100.36 respectively. The testicles of the infected rams revealed pericapsular hemorrhages. No fasciola eggs or flukes were observed in the control rams and no pathology observed on the testicles. This study revealed that fasciola eggs count may be a tool to determine the success of experimental infection and the estimated number of recovered flukes used in the study. It is concluded that fasciola eggs and large population of flukes had significant influence in the establishment of liver and testicular pathology in Yankasa rams.

The Diagnosis of Human Fascioliasis by Enzyme-Linked Immunosorbent Assay (ELISA) Using Recombinant Cathepsin L Protease

BackgroundFascioliasis is a worldwide parasitic disease of domestic animals caused by helminths of the genus Fasciola. In many parts of the world, particularly in poor rural areas where animal disease is endemic, the parasite also infects humans. Adult parasites reside in the bile ducts of the host and therefore diagnosis of human fascioliasis is usually achieved by coprological examinations that search for parasite eggs that are carried into the intestine with the bile juices. However, these methods are insensitive due to the fact that eggs are released sporadically and may be missed in low-level infections, and fasciola eggs may be misclassified as other parasites, leading to problems with specificity. Furthermore, acute clinical symptoms as a result of parasites migrating to the bile ducts appear before the parasite matures and begins egg laying. A human immune response to Fasciola antigens occurs early in infection. Therefore, an immunological method such as ELISA may be a more reliable, easy and cheap means to diagnose human fascioliasis than coprological analysis.Methodology/Principal findingsUsing a panel of serum from Fasciola hepatica-infected patients and from uninfected controls we have optimized an enzyme-linked immunosorbent assay (ELISA) which employs a recombinant form of the major F. hepatica cathepsin L1 as the antigen for the diagnosis of human fascioliasis. We examined the ability of the ELISA test to discern fascioliasis from various other helminth and non-helminth parasitic diseases.Conclusions/SignificanceA sensitive and specific fascioliasis ELISA test has been developed. This test is rapid and easy to use and can discriminate fasciola-infected individuals from patients harbouring other parasites with at least 99.9% sensitivity and 99.9% specificity. This test will be a useful standardized method not only for testing individual samples but also in mass screening programs to assess the extent of human fascioliasis in regions where this zoonosis is suspected.

Epidemiology of human fascioliasis and intestinal parasitosis among schoolchildren in Lake Tana Basin, northwest Ethiopia

Parasitic diseases are the second most frequent cause of outpatient morbidity in Ethiopia. A cross-sectional study was conducted in Lake Tana Basin, northwest Ethiopia, from November 2007 to February 2008, to assess the magnitude and associated risk factors for parasitic diseases, including human fascioliasis. We examined 520 stool samples from randomly selected schoolchildren in six schools by microscopy. Rapid sedimentation and Kato-Katz techniques were used to detect and count Fasciola and Schistosoma eggs. The formol-ether concentration method was used for the identification of other helminth eggs, larvae and cysts of protozoan parasites. The overall prevalence of intestinal parasitic infections was 71.3% (95% CI 67.3-75.1%). Hookworm was the predominant intestinal parasite (23.5%, 95% CI 19.8-27.1%), followed by Ascaris lumbricoides (18.5%, 95% CI 15.2-21.9%) and Schistosoma mansoni (16.7%, 95% CI 13.5-19.9%). One hundred and sixty-three (31.4%) children had multiple parasitic infections. The most relevant finding was a prevalence of Fasciola spp. of 3.3% in an area where only sporadic cases have been reported previously. The risk of Fasciola spp. infection was significantly associated with raw vegetable consumption, use of unsafe drinking water sources, irrigation practices and sheep and/or cattle ownership. Irrigation practices, male gender, raw vegetable consumption and use of unsafe drinking water sources were risk factors for S. mansoni infection. A high prevalence of parasitic infections among children in the region was found, including a relatively high prevalence of Fasciola spp. infection. Epidemiological studies on the magnitude of parasitic infections in different regions will enable high-risk communities to be identified and allow for planning of appropriate interventions.

Study on ovine fasciolosis: Prevalence and associated risk factors in North Gondar Zone, Ethiopia

A cross sectional study was conducted from November to April, 2011 in three districts (Gondar town, Gondar Zuria, and Dembia) of North Gondar Administrative Zone (NGAZ). The objectives of the study, were to determine the prevalence ovine fasciolosis and to asses risk factors associated with fasciolosis in sheep. Coprological examinations, was used to collect fresh fecal samples directly from live sheep during the study period. Out of the total 400 fecal samples examined, 173 (43.3%) were positive for Fasciola eggs. There was no statistically significant difference (P > 0.05) among age groups (young (45.8%), adult (39.7%), and old (42.4%)) and between sexes (male (42.74%) and female (43.35%)), respectively. However, there was statistically significant variation (P < 0.05) between different body conditions of the animal (good body condition (28.5%), medium (41.7%), and poor body condition (97.8%)). The prevalence of fasciolosis was higher in animals with poor body condition. Also, there was statistically significant difference among the three districts (P < 0.05). The highest prevalence rate was detected in Gondar Zuria districts (34.6%), Dembia (43.7%), and Gondar town (51.9%), correspondingly. This study indicated that, fasciolosis is the major obstacles of sheep production in the study area by inflicting remarkable direct and indirect losses to the animal. Therefore, strategic deworming of sheep with antihelminthics can reduce the prevalence rate of the parasites. Key words: Ethiopia, North Gondar, ovine, coprological, fasciolosis

Bovine fasciolosis at increasing altitudes: Parasitological and malacological sampling on the slopes of Mount Elgon, Uganda

BackgroundTo clarify the extent and putative transmission zone of bovine fasciolosis on the slopes of Mount Elgon, Uganda, conjoint parasitological and malacological surveys, inclusive of inspection of animals at slaughter, were undertaken at increasing altitudes.ResultsA total of 239 cattle were sampled across eight locations ranging in elevation from 1112-2072 m. Faecal material was examined for presence of Fasciola eggs and sera were tested by ELISA for antibodies against Fasciola antigens. Bolstering this, 38 cattle at slaughter from 2 abattoir sites at 1150 m and 1947 m were inspected; in addition, wild buffalo stool (n = 10) opportunistically picked within Mount Elgon National Park (MENP) at 3640 m was examined. By faecal egg detection, prevalence of Fasciola gigantica at low (<1500 m) and high (>1500 m) altitude sites was 43.7% (95% CI 35.4-52.2) and 1.1% (95% CI 0.0-6.0), respectively, while by ELISA was much higher, low altitude - 77.9% (95% CI 69.7-85.4) and high altitude - 64.5% (95% CI 51.3-76.3). The decline in prevalence with increasing altitude was corroborated by abattoir sampling. Thirty seven aquatic habitats, ranging from 1139-3937 m in altitude were inspected for freshwater snails, 12 of which were within MENP. At lower altitudes, Lymnaea (Radix) natalensis was common, and often abundant, but at higher altitudes became much rarer ceasing to be found above 1800 m. On the other hand, Lymnaea (Galba) truncatula was found only at altitudes above 3000 m and within MENP alone. The snail identifications were confirmed by DNA analysis of the ribosomal 18S gene.ConclusionsActive infections of F. gigantica in cattle are common in lower altitude settings but appear to diminish with increasing elevation. This is likely due to a growing paucity of intermediate hosts, specifically populations of L. natalensis for which a natural boundary of 1800 m appeared. Although F. hepatica was not encountered, the presence of several populations of L. truncatula at elevations over 3000 m point towards a potential transmission zone within MENP should this parasite be introduced.

Vasculitis secundaria a infección por Fasciola hepática

There is a case of a 38 year-old male patient coming from an area where hepatic fascioliasis is endemic in Peru. He was hospitalized because he showed 4 weeks of symptoms like fever, intense myalgias, erythematous and painful injuries on limb extensions. The electromyography and nerve conduction velocity showed a global inflammatory myopathy. A skin biopsy showed polyarteritis nodosa-type vasculitis. During the evaluation process prior to the immunosuppressive therapy, hepatic Fasciola eggs were found in the parasitological examination of stools. The fascioliasis diagnosis was confirmed by fas2-ELISA: 0.46 (VN <0.20). Clinical symptoms started to subside after treatment with ticlabendazol. Contact with the patient was maintained for a year and there was no evidence of disease recurrence, and he was asymptomatic.

Seasonal and monthly prevalence pattern of fasciolosis in buffaloes and its relation to some climatic factors in northeastern areas of Punjab, Pakistan

Summary A study was conducted in the northeastern areas of Punjab province (Pakistan) to analyse the monthly and seasonal pattern of fasciolosis in buffaloes and its relation to some climatic factors (temperature, humidity, rainfall and pan-evaporation) was also worked out. The faecal samples of buffaloes were collected from April 2003 to March 2005 on a monthly basis from randomly selected areas and analysed for the presence of Fasciola egg. From 7200 samples, 1058 (14.69%) were found positive. Seasonal data showed the highest prevalence and egg count (EPG) in autumn and the lowest in spring. Monthly results showed the highest prevalence in September (32.33%) and the lowest in May (4.83%), while mean EPG was highest in October (567 ± 95.5) and the lowest in June (3.2 ± 0.48). Statistically, significant difference (P<0.05) was noted within seasonal and monthly prevalences. Impact of humidity was found significant (P<0.05) on disease as compared to other climatic factors.

Prevalence of Fasciola in cattle and of its intermediate host Lymnaea snails in central Vietnam

The aims of this study were to investigate the prevalence of natural Fasciola infections in both the definitive hosts (cattle) and the intermediate hosts (Lymnaea snails) in central Vietnam. A total of 1,075 fecal samples, randomly collected from cattle in Binh Dinh, Khanh Hoa, and Phu Yen provinces, were examined for Fasciola eggs by a sedimentation method. The overall prevalence of Fasciola was 45.3 %. A subset of the animals (235) was also screened for antibodies against Fasciola by an enzyme-linked immunosorbent assay. Overall, 46.3 % of these animals were shedding Fasciola eggs while 87.2 % were Fasciola seropositive. A lower prevalence of Fasciola was observed in calves ≤ 2 years of age (37.6 %) compared to that in cattle >2 years of age (53.7 %) (p < 0.05). The prevalence in the rainy season (50.8 %) was significantly different to that in the dry season (38.1 %) (p < 0.05). Of the 3.269 Lymnaea viridis and 1.128 Lymnaea swinhoei examined, 31 (0.95 %) and seven (0.62 %), respectively, were found to be infected with Fasciola. This appears to be the first epidemiological survey of the prevalence of Fasciola in cattle and snails in these three provinces in central Vietnam.

Efficacy of a Single Oral Dose of Oxfendazole against Fasciola hepatica in Naturally Infected Sheep

The efficacy of a single oral dose of 30 mg/kg of oxfendazole against Fasciola hepatica was evaluated in a controlled study in naturally infected sheep. Sheep were diagnosed by stool microscopy after sedimentation, and positive animals were randomized to oxfendazole (N = 20) or no treatment (N = 20). A new stool exam was performed 10 days after treatment. All stool microscopies were performed masked to the treatment group. No side effects were noticed. All sheep in the control group remained infected with similar counts of eggs per gram of stools. None of the animals in the treatment group showed Fasciola eggs in stools after 10 days of treatment. A single dose of oxfendazole is highly effective against F. hepatica, providing a new drug alternative for the control of fascioliasis or integrated zoonosis control.

The Variable Presentations and Broadening Geographic Distribution of Hepatic Fascioliasis

We report 2 unrelated cases of hepatic fascioliasis in travelers returning to the United States from Africa and the Middle East. The first case presented with acute infection. Prominent clinical features included abdominal pain, elevated liver transaminases, serpiginous hepatic lesions, pericapsular hematoma, and marked peripheral eosinophilia. The second case was diagnosed in the chronic stage of infection and presented with right upper quadrant abdominal pain, cystic hepatic lesions, and an adult fluke in the common bile duct. We review the life cycle of Fasciola species, the corresponding clinical features during the stages of human infection, diagnostic methods, and the evolving understanding of the epidemiology of human fascioliasis, particularly emphasizing fascioliasis in African countries.