Schistosoma mansoni infection among preschool age children attending Erer Health Center, Ethiopia and the response rate to praziquantel.

OBJECTIVE: Preschool age children (PSAC) are excluded from community based praziquantel treatment programs mainly due to paucity of evidence on the magnitude of schistosomiasis, efficacy and safety of this treatment in PSAC. The aim of this study is to assess Schistosoma mansoni infection rate and evaluate response to praziquantel in PSAC. A facility based longitudinal study was employed from April to June 2016 at Erer Health Center, Eastern Ethiopia. Stool sample was examined for schistosomiasis in 236 PSAC and repeated after 4 weeks post-treatment in positive individuals. Treatment outcomes were recorded and interpreted. RESULTS: Out of the 236 study participants, 59 (25%) were infected with S. mansoni. Praziquantel treatment (40 mg/kg) resulted in 96.4% cure rate and 99.4% egg reduction rate. Children of 3-5 year old were significantly affected with S. mansoni infection. Nausea and fatigue were common mild adverse events within 4 h of treatment however moderate and severe adverse events and allergic reactions were not observed. In conclusion, praziquantel at 40 mg/kg, the dose utilized in standard care for school age children, is tolerable and efficacious in the treatment of S. mansoni infection in PSAC, which calls for the healthcare system to provide appropriate service for this population.

Gastrointestinal nematode infection and feeding behaviour of goats in a heterogeneous vegetation: No evidence of therapeutic self-medication.

The aim of this study was to identify modifications in the feeding behaviour of goats browsing a tropical deciduous forest (TDF) when natural gastrointestinal nematode (GIN) infection was suppressed. Continuous bite monitoring through direct observation was implemented in 12 Criollo goats (adults, non-pregnant) foraging for 4 h per day during the rainy season. In the first Period (P1, one observation point) all goats were maintained with natural GIN infection. In the second Period (P2, three observation points), goats were equally distributed into 2 groups: i) moxidectin treated group (TG) used in a suppressive scheme; and ii) naturally infected group (IG). For each observation point, goats were monitored at three timepoints per day (80 min each), for three consecutive days, to estimate their intake of dry matter (DM), condensed tannins (CT), crude protein, metabolizable energy and digestible DM. Live weight (LW), faecal samples and blood samples were obtained every 28 days to determine LW change, faecal egg counts (FEC) and packed cell volume (PCV). During P1 and P2, the TG and IG had similar LW change and PCV. During both periods, the intake of DM, CT and all macronutrients were similar for TG and IG. The suppression of GIN infection did not modify the feeding behaviour of goats. Therefore, a therapeutic self-medicative behaviour was not identified in Criollo goats browsing a TDF.

Sensitivity of the Point-of-Care Circulating Cathodic Antigen Urine Cassette Test for Diagnosis of Schistosoma mansoni in Low-Endemicity Settings in Côte d'Ivoire.

The sensitivity of a point-of-care circulating cathodic antigen (POC-CCA) urine cassette test for diagnosis of Schistosoma mansoni in low-endemicity settings is poorly understood. We conducted a cross-sectional survey in 14 villages in western Côte d'Ivoire and diagnosed children aged 9-12 years for schistosomiasis. Two stool samples were subjected to triplicate Kato-Katz thick smears each for diagnosis of S. mansoni, whereas a single urine sample was examined by POC-CCA for S. mansoni, filtration for Schistosoma haematobium, and reagent strip for microhematuria. According to the Kato-Katz technique, we found 45 out of 681 children positive for S. mansoni (6.6%) with a mean intensity among infected children of 72.2 eggs per gram of stool. Point-of-care circulating cathodic antigen revealed a prevalence of S. mansoni of 33.0% when trace results were considered positive and 12.5% when trace results were considered negative. Eggs of S. haematobium were found in eight participants (1.2%), whereas the prevalence of microhematuria was 13.5%. A single POC-CCA urine cassette test revealed a several-fold higher prevalence of S. mansoni than multiple Kato-Katz thick smears in this low-endemicity area. Our findings have important ramifications for choosing an appropriate diagnostic tool in low-endemic areas that might be targeted for elimination.

Survey on Intestinal Helminthic Infection Status of Students in Two Counties, Hadong-gun and Goseong-gun, Korea.

This study was conducted to investigate the prevalence of intestinal parasites among students from Goseonggun, Gangwon-do and Hadong-gun, Gyeongsangnam-do as typical low and high endemic counties. From May to July 2017, a total of 2,033 fecal samples were collected at 27 elementary, 10 junior high, and 8 high schools from 2 counties and examined by the Kato-Katz technique for egg-positive surveys (Collection rate: 37.02% [2,033/5,492]). Of the participants examined, 13 (0.64%) were found to harbor eggs of 3 parasitic species, Trichuris trichiura, Clonorchis sinensis and Metagonimus yokogawai. Based on the regional distribution, the egg-positive rate in Goseong-gun was 0% (0/550) and that in Hadong-gun was 0.88% (13/1,483). The positive rates for C. sinensis, M. yokogawai, and T. trichiura in Hadonggun were 0.20% (3/1,483), 0.61% (9/1,483), and 0.07% (1/1,483), respectively. The present survey showed that the prevalence of parasitic infection among students is currently very low even in remote, previously endemic areas, and the present status of parasitic diseases can be summarized as some transmission of fish/food-borne trematodes. Thus, it is necessary to carefully, continuously monitor the trematode infection status, particularly of C. sinensis and M. yokogawai.

Modelling anthelmintic resistance by extending eggCounts package to allow individual efficacy.

The same anthelmintic treatment can have variable efficacy on individual animals even if the parasite population is homogenously susceptible. An extension of the R package eggCounts is proposed to take individual efficacy into account using a Bayesian hierarchical model. A simulation study is conducted to compare the performance of five different methods on estimating faecal egg count reduction and its uncertainty interval. Simulation results showed the individual efficacy model offered robust inference to two different data simulation procedures with low root mean squared error on the reduction estimate and appropriate uncertainty estimates. Different methods were used to evaluate the anthelmintic resistance in a dataset from USA with sheep and cattle faecal egg counts, where a strong anthelmintic resistance was detected. Open-source statistical tools were updated to include the proposed model.

Anthelmintic efficacy against equine strongyles in the United States.

Equine strongyle parasites are ubiquitous in grazing equids across the world. Anthelmintic resistance is widely developed in cyathostomin populations, but very few surveys have evaluated anthelmintic efficacy in equine populations in the United States, and most of these are over 15 years old. The present study was carried out as part of the National Animal Health Monitoring Systems (NAHMS) Equine 2015-2016 study. The aims were to investigate anthelmintic treatment efficacy by means of the fecal egg count reduction test (FECRT) and identify parameters associated with decreased efficacy. Data were collected from equine operations in 28 states via questionnaires and fecal samples submitted for fecal egg count analysis. Participants were instructed to collect samples from six equids at the day of anthelmintic treatments and 14 days later, and they were asked to include an empty syringe with a legible label of the anthelmintic product used in the shipment. Overall, dewormer treatment was effective for 76.3% of operations (84.6% of animals). Macrocyclic lactone use was effective for 88.7% of operations (95.0% of animals) while pyrimidine/benzimidazole use was effective for 21.4% of operations (43.5% of animals). Univariate analysis revealed that overall, macrocyclic lactones exhibited significantly higher efficacy than the pyrimidine and benzimidazole drug classes (p < 0.0001). There were no statistically significant differences observed between geographic regions (West, South Central, North East, and Southeast). Body weight (p = 0.0355), amount of anthelmintic administered (p = 0.0119), and operation size (p = 0.0162) were statistically associated with anthelmintic efficacy, while anthelmintic treatment frequency in the previous 12 months was not (p = 0.7081). Multiple, mixed-effect logistic regression revealed that anthelmintic drug class (p < 0.0001) was the most impactful factor in predicting anthelmintic efficacy, after accounting for operation size, region and clustering of equids at the operation level. Pasture rotation (p = 0.0129) also demonstrated a significant effect using this model. These data document widespread occurrence of reduced anthelmintic efficacy of benzimidazole and pyrimidine products against strongyle infections in equids in the United States. Anthelmintic efficacy patterns were relatively uniform between the four studied regions, and some epidemiological factors were identified to be associated with anthelmintic efficacy against strongyle infections. This information can be useful in devising sustainable parasite control strategies in the future.

Epidemiology and effect of gastrointestinal nematodes on beef cattle from tropical Argentina.

The aim of this work was to study the epidemiology and the harmful effect of gastrointestinal nematodes (GINs) on beef cattle in the piedmont forest and grassland region of northwestern Argentina, between March 2015 and March 2016. Sixty weaned female calves were divided into three groups: STG-calves treated systematically with 200 mcg/kg moxidectin every 40-50 days; LTG-calves treated as usually locally implemented, with 200 mcg/kg ivermectin on May 4 and August 5; and UTG-calves not receiving treatment. Moreover, a group of 20 untreated first-calving cows was monitored. Eggs per gram of faeces (epg) and faeces cultures were performed. Live weight gain (LWG) was recorded. Differences among groups were compared using analysis of variance and Tukey test. At the start of the experiment, mean epg was from moderate to high (595 ± 480); therefore, this group was treated in May. Mean UTG epg peaked (907 ± 754) in mid-winter, decreasing toward spring. LTG epg only decreased partially after treatment, showing 54.2% of ivermectin efficacy. Epg values of STG were always negligible values (95.8% of moxidectin efficacy). The dominant nematode genus was Cooperia (81.9%), followed by Haemonchus (15.5%). The effect of treatments was evident from middle autumn, with STG showing a significantly (p < 0.002) higher LWG than the other groups. Toward the end of the trial, LWG of STG and LTG increased by 27.2 and 8.2%, respectively, to those of UTG. This preliminary study showed a winter epg peak and a negative effect of GINs on LWG, even in moderately infected calves.

Parâmetros sanguíneos e opg (ovos por grama de fezes) de ovelhas mestiças da raça Dorper em diferentes graus do método famacha / Blood parameters and epg (eggs per gram of feces) of crossbred Dorper sheep race in differents degrees of the famacha method / Parámetros sanguíneos y hpg (conteo de huevos en heces) de ovejas mestizas de la raza Dorper en diferentes grados del método famacha

A criação de ovinos no Brasil vem se desenvolvendo em larga escala nos últimos anos, entretanto, as verminoses continuam causando grandes perdas no setor de ovinocultura. Dentre as verminoses, as helmintoses são responsáveis pelos maiores prejuízos na criação de ovinos, sendo o principal parasita causador destas perdas o Haemonchuscontortus, predominante em diversas regiões do Brasil. Grande parte desta patogenicidade é proveniente de sua hematofagia e lesão na mucosa do abomaso. Esta perda de sangue implica também na perda de outros elementos figurados sanguíneos. Animais com intensa parasitose podem apresentar, além da anemia, leucopenia por linfopenia e perdas proteicas que caracterizam uma hipoproteinemia. Dessa forma, métodos de avaliação do estado sanitário dos animais foram desenvolvidos como estratégia auxiliar no controle do Haemonchus. O grau de anemia dos animais do experimento foi determinado pelo método Famacha e por métodos laboratoriais: albumina, hematócrito, hemoglobina, proteína plasmática total, contagem total de eritrócitos, volume globular, leucócitos totais, linfócitos e OPG (ovos por grama de fezes) em ovelhas. O objetivo foi correlacionar o método Famacha com os resultados dos parâmetros sanguíneos, para conhecer de forma mais rápida, o estado de anemia do animal como indicador de hemoncose. Foram utilizadas para o experimento 20 ovelhas mestiças da raça Dorper. As coletas de sangue, fezes e a avaliação da coloração da conjuntiva ocular por meio do método Famacha foram realizadas no mesmo dia. Foi observado um maior número de animais com o grau de Famacha2, os animais com grau 1 apresentaram menor número de OPG, maior número de hemácias, maior quantidade de hemoglobina, maior hematócrito quando comparados com os animais com graus 2 e 3. Conclui-se que o método Famacha é eficaz na estratégia de combate da hemoncose ovina.

Sheep farming in Brazil has been developing in a large scale in recent years. However, worms continue to cause great losses in sheep production. Among them, helminthes are responsible for major losses in sheep production, with the main parasite causing such losses being Haemonchuscontortus, prevalent in several regions in Brazil. Much of this pathogenicity comes from its hematophagy and the damage it causes to the abomasum mucosa. This blood loss also means the loss of other blood-formed elements. Animals with severe parasitic disease may present, as well as anemia, leukopenia by lymphopenia and protein loss characterizing hypoproteinemia. Thus, methods of assessing the sanitation status of animals were developed as a strategy to assist in the control of Haemonchus. The degree of anemia in experimental animals was determined by the Famacha method and by laboratory methods: albumin, hematocrit, hemoglobin, total plasma protein, total erythrocyte count, erythrocyte volume, total leukocytes, lymphocytes and EPG (eggs per gram of feces) in sheep. The purpose was to correlate the Famacha method with the blood parameter results in order to have a quicker answer about the animal's anemia state as a haemonchosis indicator. A total of 20 crossbred Dorper sheep were used in this experiment. The collection of blood and feces, and conjunctival staining by the Famacha method were performed on the same day. An increased number of animals presenting Famacha grade 2 could be observed, while animals with grade 1 had fewer EPG, higher number of erythrocytes, greater amount of hemoglobin, and better hematocrit compared to animals with grade 2 and 3. It can be concluded that the Famacha method is an effective fighting strategy against ovine haemonchosis.

La cría de ovinos en Brasil viene desarrollándose a gran escala en los últimos años. Sin embargo, los helmintos siguen causando grandes pérdidas en el sector de la producción ovina. Entre las parasitosis, los helmintos son responsables por mayores pérdidas en el ganado ovino, el principal parásito que causa estas pérdidas es el Haemonchus contortus, que prevalece en varias regiones de Brasil. Gran parte de esta patogenicidad proviene de su hematofagia y lesión de la mucosa del abomaso. Esta pérdida de sangre también significa la pérdida de otros elementos figurados sanguíneos. Los animales con enfermedad parasitaria grave pueden presentar anemia, leucopenia por linfopenia y pérdida de proteínas que caracterizan una hipoproteinemia. Por lo tanto, métodos de evaluación del estado de salud de los animales fueron desarrollados como estrategia de ayuda en el control de Haemonchus. El grado de anemia de los animales del experimento fue determinado por el método Famacha e por métodos de laboratorio: albúmina, hematocrito, hemoglobina, proteína plasmática total, conteo total de eritrocitos, volumen globular, leucocitos totales, linfocitos y HPG (conteo de huevos en heces) en ovinos. El objetivo fue correlacionar el método Famacha con los resultados de los parámetros sanguíneos, para conocer de forma más rápido el estado de anemia del animal como indicador de hemoncose. Se ha utilizado para el experimento 20 ovejas mestizas de la raza Dorper. Las muestras de sangre, heces y la evaluación de la coloración de la conjuntiva ocular por el método Famacha se realizaron en el mismo día. Se ha observado un mayor número de animales con el grado de Famacha2, los animales con grado 1 presentaron menor número de HPG, mayor número de hematíes, mayor cantidad de hemoglobina, mayor hematocrito en comparación con los animales con grado 2 y 3. Se concluye que el método Famacha es eficaz en la estrategia de combate de la haemonchosis ovina.

Predictive Value of School-Aged Children's Schistosomiasis Prevalence and Egg Intensity for Other Age Groups in Western Kenya.

World Health Organization recommendations for the timing and target population for mass drug administration (MDA) for schistosomiasis are based on the prevalence of infection in school children within a given community. In a large study comparing MDA approaches for Schistosoma mansoni control, we evaluated whether prevalence of infection and egg burdens in 9- to 12-year-old students reflected infection levels in young children and adults in the same community. Cross-sectional surveys of preadolescents (9-12 years old) were compared with those of first year students (5-8 years old) in 225 villages and adults (20-55 years old) in 150 villages along the Kenyan shores of Lake Victoria. Village schistosomiasis prevalence and intensity levels in preadolescents strongly correlated (P < 0.0001) with prevalence and infection intensity for other age groups in the community. Our findings suggest that S. mansoni prevalence and intensity among 9- to 12-year-olds are valid for community sampling purposes in mapping for MDAs.

Reducing Unnecessary and Duplicate Ordering for Ovum and Parasite Examinations and Clostridium difficile PCR in Immunocompromised Patients by Using an Alert at the Time of Request in the Order Management System.

We implemented hospital information system (HIS) alerts to deter unnecessary test orders for ovum and parasite (O&P) exams and Clostridium difficile PCR. The HIS alerts decreased noncompliant O&P orders (orders after >72 h of hospitalization) from 49.8% to 30.9%, an overall decrease of 19%, and reduced noncompliant C. difficile PCR orders (orders <7 days after a previous positive result) from 30.6% to 19.2%, an overall decrease of 31.9%.

[Helminth prevalence in a waste-water plant at El Rosal, Cundinamarca]. / Prevalencia de helmintos en la planta de aguas residuales del municipio El Rosal, Cundinamarca.

OBJECTIVE: Assessing helminth egg prevalence in sludge and raw and treated wastewater from a wastewater treatment system located in the village of El Rosal, Cundinamarca. METHODOLOGY: 30 wastewater and 10 sludge samples from the El Rosal plant were taken during a 10-week period. The sludge and water samples were processed according to the Bailinger and the official Mexican standard methodology, respectively. Egg viability was determined by the method described by Victórica & Galván and the Mexican official standard. RESULTS: Descriptive statistics were used for analysing data. 100 % of the untreated wastewater samples showed the presence of eggs and at least one viable helminth egg/litre was found in 90 % of them. 90 % of the treated wastewater samples were positive for the presence of eggs, finding that 70 % had at least one viable egg. All raw wastewater samples being dumped directly into the stream were positive for helminths; the same situation was found at the time of the viability test. All sludge samples were positive for helminths, finding that 100 % of these had at least one viable egg. CONCLUSION: Using this water for crop irrigation and using the sludge as fertiliser is a potential risk for public health. The sludge can only be used in forestry activities, as long as it does not come into contact with humans.

The contribution of simple random sampling to observed variations in faecal egg counts.

It has been over 100 years since the classical paper published by Gosset in 1907, under the pseudonym "Student", demonstrated that yeast cells suspended in a fluid and measured by a haemocytometer conformed to a Poisson process. Similarly parasite eggs in a faecal suspension also conform to a Poisson process. Despite this there are common misconceptions how to analyse or interpret observations from the McMaster or similar quantitative parasitic diagnostic techniques, widely used for evaluating parasite eggs in faeces. The McMaster technique can easily be shown from a theoretical perspective to give variable results that inevitably arise from the random distribution of parasite eggs in a well mixed faecal sample. The Poisson processes that lead to this variability are described and illustrative examples of the potentially large confidence intervals that can arise from observed faecal eggs counts that are calculated from the observations on a McMaster slide. Attempts to modify the McMaster technique, or indeed other quantitative techniques, to ensure uniform egg counts are doomed to failure and belie ignorance of Poisson processes. A simple method to immediately identify excess variation/poor sampling from replicate counts is provided.

Physician use of parasite tests in the United States from 1997 to 2006 and in a Utah Cryptosporidium outbreak in 2007.

Parasitic infection is uncommon in the United States, but surveys suggest that physicians test when the presence of parasites is unlikely and fail to order appropriate testing when suspicion is high. Numerous studies confirm that immunoassays are more sensitive for Giardia and Cryptosporidium detection, but our experience was that physicians preferentially used ovum and parasite examination (O&P). We conducted a retrospective study of fecal parasite testing at a referral laboratory nationally (1997 to 2006) and during a Cryptosporidium outbreak (Utah, 2007) to correlate physician use of O&P and enzyme immunoassays (EIAs) with the yield of parasites detected. Nationally, of 170,671 episodes, 76.0% (n = 129,732) included O&P, 27.9% (n = 47,666) included Giardia EIA, and 5.7% (n = 9,754) included Cryptosporidium EIA. Most pathogens were Giardia or Cryptosporidium. More episodes were positive when EIA was performed (n = 1,860/54,483 [3.4%]) than when O&P only was performed (n = 1,667/116,188 [1.4%]; P < 0.001), and EIA was more sensitive than O&P. However, more O&P results were positive among patients with both O&P and EIA performed (2.5%) than among those with O&P only performed (1.4%; P < 0.001), suggesting that patients tested by O&P only may have been at lower risk. During the first 10 weeks of the outbreak, physicians also preferentially used O&P over EIA, but no Cryptosporidium cases were detected by O&P. We conclude that clinicians frequently use O&P testing when test performance and epidemiology support the use of immunoassays or no testing. We recommend that stool O&P be limited to patients with negative immunoassay results and persistent symptoms or individuals at increased risk for non-Giardia, non-Cryptosporidium infection. An evidence-based algorithm for the evaluation of patients with suspected intestinal parasitic infection is proposed.

Efeito in vitro do extrato etanólico das folhas do melão-de-São-Caetano (Momordica charantia L. ) sobre ovos e larvas de nematóides gastrintestinais de caprinos / In vitro effect of the ethanolic extract of "melão de São Caetano" (Momordica charantia L. ) leaves on the eggs and larvae of gastrointestinal nematodes from goats

O experimento in vitro foi realizado para avaliar a ação do extrato etanólico das folhas do melão-de-São-Caetano (Momordica charantia L.) sobre o desenvolvimento de ovos e motilidade de larvas de nematóides gastrintestinais de caprinos. As larvas foram obtidas de coproculturas e a recuperação de ovos foi feita pela técnica dos quatro tamises, a partir de fezes de caprinos naturalmente infectados da mesorregião do Sertão Paraibano. O extrato foi utilizado nas diluições de 50; 25; 12,5; 6,25 e 3,12 por cento para ambos os testes e como controle positivo e para controle negativo, utilizou-se água destilada estéril. As placas foram examinadas ao microscópio óptico para contagem dos ovos em desenvolvimento e larvas móveis e imóveis, após 24, 48 e 72 horas de incubação. As concentrações do extrato etanólico de M. charantia e os tratamentos controle negativo e positivo diferiram quanto ao número de ovos inviáveis. No teste de motilidade larval as concentrações acima de 12 por cento apresentaram médias significativas quanto ao número de larvas inviáveis. Nas condições ensaiadas a M. charantia apresentou atividade ovicida e larvicida.

The experiment in vitro was performed to evaluate the action of the ethanolic extract of "melão de São Caetano" (Momordica charantia L.) leaves on the development of eggs and motility of larvae of gastrointestinal nematodes from goats. The nematode larvae were obtained from coproculture and the recovery of eggs was done in sieves, from feces of naturally infected goats from the Mesoregion of Paraíba State. The extract was used at the dilutions of 50, 25, 12.5, 6.25 and 3.12 percent for both tests and as positive control; for negative control, sterile distilled water was used. The plates were examined under optical microscope to count the eggs in development and mobile larvae after 24, 48 and 72 h of incubation. The concentrations of M. charantia ethanolic extract and the negative and positive controls differed as to the number of eggs that were not viable. In the larval motility test, concentrations higher than 12 percent had significant means as to the number of larvae that were not viable. Under the tested conditions, M. charantia showed larvicidal and ovicidal activity.

Analysis of multiyear studies in horses in Kentucky to ascertain whether counts of eggs and larvae per gram of feces are reliable indicators of numbers of strongyles and ascarids present.

Increasing levels of anthelmintic resistance in equine nematodes have led to recommendations of more sustainable anthelmintic treatment protocols with emphasis on parasite surveillance and diagnosis, rather than prophylactic calendar-based treatments. This requires knowledge of the diagnostic test performance of techniques for counts of eggs per gram of feces (EPG) as well as methods for culturing, counting and identifying third stage (L(3)) strongyle larvae per gram of feces (LPG). For horses, such information does not exist in the published literature. The aim of this study was to examine the relationship between worm count and fecal egg count (FEC) data for strongyle and Parascaris equorum infections as well as larval culture counts for diagnosing Strongylus spp. infections. Necropsy data from 693 horses used for critical or controlled tests, including information on total worm counts, fecal egg counts (FEC) and larval culture results collected at the University of Kentucky over a period of 50 years were analyzed. Sensitivity, specificity, positive and negative predictive values, and receiver operator characteristic (ROC) curves were generated for the larval cultures and ascarid egg counts. For the strongyle egg counts, potential FEC cutoff values for treatment were evaluated statistically by comparing the total strongyle worm counts below and above chosen cutoff values. All tests had high positive predictive values (>0.95), but moderate negative predictive values (<0.70). The negative predictive values of the larval counts were negatively affected by increasing egg count levels. Strongyle FEC cutoff values up to the level of 500 EPG yielded significantly higher strongyle worm counts in the treatment group, whereas no differences were found at higher cutoffs. This supports usage of cutoffs for treatment in the 0-500 EPG range. Altogether, the present study yields unique and useful information of widely used methods for parasite surveillance and diagnosis in equine establishments.

Prevalencia de helmintos en la planta de aguas residuales del municipio El Rosal, Cundinamarca / Helminth prevalence in a waste-water plant at El Rosal, Cundinamarca

Objetivo Determinar la prevalencia de huevos de helmintos en lodos, agua residual cruda y tratada, provenientes de un sistema de tratamiento de aguas residuales del municipio el Rosal, Cundinamarca. Metodología Se tomaron 30 muestras de agua residual, y 10 de lodos en la Planta El Rosal, durante 10 semanas. Las muestras de aguas y lodos se procesaron siguiendo los métodos de BAILENGER, y el método de la Norma Oficial Mexicana, respectivamente. La viabilidad de los huevos se determinó por el método de Victórica & Galván y la Norma Oficial Mexicana. Resultados Los datos fueron analizados con estadística descriptiva. El 100 % de las muestras de agua residual sin tratar evidenció presencia de huevos, encontrándose al menos un huevo viable de helminto/litro en el 90 % de las mismas. El 90 % de las aguas residuales tratadas fueron positivas para la presencia de huevos, encontrándose que el 70 % presentaba al menos 1 huevo viable. Todas las muestras de agua residual cruda que se vierten directamente a la quebrada, fueron positivas a helmintos, igual situación se encontró al momento de realizar la prueba de viabilidad. Todos los lodos fueron positivos para helmintos, encontrándose que en el 100 % de estos, al menos un huevo fue viable. Conclusión El uso de estas aguas para riego de hortalizas, y el uso de estos lodos como abono, representa un riesgo potencial para la salud pública. Los lodos solo pueden ser usados en actividades forestales, siempre y cuando no estén en contacto con humanos.

Objective Assessing helminth egg prevalence in sludge and raw and treated wastewater from a wastewater treatment system located in the village of El Rosal, Cundinamarca. Methodology 30 wastewater and 10 sludge samples from the El Rosal plant were taken during a 10-week period. The sludge and water samples were processed according to the Bailinger and the official Mexican standard methodology, respectively. Egg viability was determined by the method described by Victórica & Galván and the Mexican official standard. Results Descriptive statistics were used for analysing data. 100 % of the untreated wastewater samples showed the presence of eggs and at least one viable helminth egg/litre was found in 90 % of them. 90 % of the treated wastewater samples were positive for the presence of eggs, finding that 70 % had at least one viable egg. All raw wastewater samples being dumped directly into the stream were positive for helminths; the same situation was found at the time of the viability test. All sludge samples were positive for helminths, finding that 100 % of these had at least one viable egg. Conclusion Using this water for crop irrigation and using the sludge as fertiliser is a potential risk for public health. The sludge can only be used in forestry activities, as long as it does not come into contact with humans.

In vitro effects of artesunate on the survival of worm pairs and egg production of Schistosoma mansoni.

The effect of artesunate (ART) on the survival time of adult worm pairs of Schistosoma mansoni and on their egg output during in vitro culture was assessed. ART significantly decreased the survival time of both paired male and female worms at concentrations of 5, 10, 20 and 40 mg l- 1 during in vitro cultivation. An inhibitory effect of ART on the daily egg output of paired female worms during in vitro cultivation was also observed.

The influence of pregnancy on intestinal parasite infection in Thai women.

The relationship between pregnancy and both the susceptibility and pathogenicity of parasite infections is disputed. This study compares the prevalence and intensity (as measured by density of eggs in stool samples) of intestinal helminth infections in pregnant and control groups of women from Khon Kaen Province in the northeast of Thailand. Stool samples were taken at the end of the first, second and third trimesters of pregnancy as well as 2 months after parturition and compared for the two groups. There were no significant changes in the prevalence of any of the common helminth species during the course of pregnancy or between the pregnant and control groups. Nor was there any evidence that the density of helminth eggs in the stool samples differed between sample times or between the pregnant and control groups. Our study therefore supports the hypothesis that pregnancy does not influence the course of human infection with helminths.

Repeatability of paired counts.

The Bland and Altman technique is widely used to assess the variation between replicates of a method of clinical measurement. It yields the repeatability, i.e. the value within which 95 per cent of repeat measurements lie. The valid use of the technique requires that the variance is constant over the data range. This is not usually the case for counts of items such as CD4 cells or parasites, nor is the log transformation applicable to zero counts. We investigate the properties of generalized differences based on Box-Cox transformations. For an example, in a data set of hookworm eggs counted by the Kato-Katz method, the square root transformation is found to stabilize the variance. We show how to back-transform the repeatability on the square root scale to the repeatability of the counts themselves, as an increasing function of the square mean root egg count, i.e. the square of the average of square roots. As well as being more easily interpretable, the back-transformed results highlight the dependence of the repeatability on the sample volume used.

Survey of 11 western states for heartworm (Dirofilaria immitis) infection, heartworm diagnostic and prevention protocols, and fecal examination protocols for gastrointestinal parasites.

Heartworm infection in dogs and cats in the western United States is a fairly new phenomenon, and for this reason it is often considered to be of minimal significance. The purpose of this survey was to collect data from 11 western states (Arizona, California, Colorado, Idaho, Montana, Nevada, New Mexico, Oregon, Utah, Washington, and Wyoming) in an effort to assess awareness of heartworm disease and identify areas in which improvement in understanding is needed. To accomplish this goal, veterinary clinics and hospitals in these states were sent a one-page survey in early 2006. The results of the survey demonstrate that cases of heartworm disease have been reported in all 11 states, illustrating the importance of annual testing and the routine use of preventives.