Multi-intervention integrated deworming strategy for sustained control of soil-transmitted helminths infections: a case study in Jiangsu Province, China.

BACKGROUND: Soil-transmitted helminths (STH) infections still present a global health problem. Mass drug administration (MDA) is a widely applied strategy to reduce morbidity and mortality caused by STH. Yet, this approach has some shortcomings. In this study, we analyzed the impact of a multi-intervention integrated deworming approach including MDA, health education (HE), and environmental sanitation improvements (ESI) for sustained STH control in Jiangsu Province of China that was applied from 1989 to 2019. METHODS: Data, including infection rate of STH, medications used, coverage of the medication, non-hazardous lavatory rate, and household piped-water access rate in rural areas, and actions related to HE and ESI were collected (from archives) and analyzed in this retrospective descriptive study. Pearson's correlation analysis was applied to test correlations. RESULTS: There was a dramatic decline in the infection rate of STH from 1989 (59.32%) to 2019 (0.12%). From 1995 to 1999, MDA and HE were recommended in rural areas. A negative correlation was observed between infection rate and medication from 1994 to 1998 (r = - 0.882, P = 0.048). From 2000 to 2005, targeted MDA was given to high-risk populations with HE continuously promoting good sanitation behaviors. From 2006 to 2014, targeted MDA + HE and ESI were used to consolidate the control effect. ESI was strengthened from 2006, and a negative correlation was observed between the coverage rate of the non-hazardous lavatory and the infection rate from 2006 to 2019 (r = - 0.95, P < 0.001). The targeted MDA was interrupted in 2015, while continuous efforts like HE and ESI contributed in sustaining STH control. CONCLUSIONS: Multi-intervention integrated deworming strategy contributes to the reduction of STH infections. This approach is a valuable example of how different interventions can be integrated to promote durable STH control.

Forecasting the effectiveness of the DeWorm3 trial in interrupting the transmission of soil-transmitted helminths in three study sites in Benin, India and Malawi.

BACKGROUND: The DeWorm3 project is an ongoing cluster-randomised trial assessing the feasibility of interrupting the transmission of soil-transmitted helminths (STH) through mass drug administration (MDA) using study sites in India, Malawi and Benin. In this article, we describe an approach which uses a combination of statistical and mathematical methods to forecast the outcome of the trial with respect to its stated goal of reducing the prevalence of infection to below 2%. METHODS: Our approach is first to define the local patterns of transmission within each study site, which is achieved by statistical inference of key epidemiological parameters using the baseline epidemiological measures of age-related prevalence and intensity of STH infection which have been collected by the DeWorm3 trials team. We use these inferred parameters to calibrate an individual-based stochastic simulation of the trial at the cluster and study site level, which is subsequently run to forecast the future prevalence of STH infections. The simulator takes into account both the uncertainties in parameter estimation and the variability inherent in epidemiological and demographic processes in the simulator. We interpret the forecast results from our simulation with reference to the stated goal of the DeWorm3 trial, to achieve a target of [Formula: see text] prevalence at a point 24 months post-cessation of MDA. RESULTS: Simulated output predicts that the two arms will be distinguishable from each other in all three country sites at the study end point. In India and Malawi, measured prevalence in the intervention arm is below the threshold with a high probability (90% and 95%, respectively), but in Benin the heterogeneity between clusters prevents the arm prevalence from being reduced below the threshold value. At the level of individual study arms within each site, heterogeneity among clusters leads to a very low probability of achieving complete elimination in an intervention arm, yielding a post-study scenario with widespread elimination but a few 'hot spot' areas of persisting STH transmission. CONCLUSIONS: Our results suggest that geographical heterogeneities in transmission intensity and worm aggregation have a large impact on the effect of MDA. It is important to accurately assess cluster-level, or even smaller scale, heterogeneities in factors which influence transmission and aggregation for a clearer perspective on projecting the outcomes of MDA control of STH and other neglected tropical diseases.

Prevalence, risk factors and health consequences of soil-transmitted helminth infection on the Bijagos Islands, Guinea Bissau: A community-wide cross-sectional study.

Soil-transmitted helminths (STH) are endemic and widespread across Sub-Saharan Africa. A community wide soil-transmitted helminth (STH) prevalence survey was performed on the island of Bubaque in Guinea-Bissau using both Kato-katz microscopy and qPCR methodology. Predictors of infection and morbidity indicators were identified using multivariable logistic regression, and diagnostic methods were compared using k statistics. Among 396 participants, prevalence of STH by microscopy was 23.2%, hookworm was the only species identified by this method and the mean infection intensity was 312 eggs per gram. qPCR analysis revealed an overall prevalence of any STH infection of 47.3%, with the majority A. duodenale (32.3%), followed by N. americanus (15.01%) and S. stercoralis (13.2%). A. lumbricoides, and T. trichiura infections were negligible, with a prevalence of 0.25% each. Agreement between diagnostic tests was k = 0.22, interpreted as fair agreement, and infection intensity measured by both methods was only minimally correlated (Rs = -0.03). STH infection overall was more common in females and adults aged 31-40. STH infection was associated with open defaecation, low socio-economic status and further distance to a water-source. The prevalence of anaemia (defined as a binary outcome by the WHO standards for age and sex) was 69.1%, and 44.2% of children were malnourished according to WHO child growth standards. Hookworm infection intensity by faecal egg count showed no statistically significant association with age (Rs 0.06) but S. Stercoralis infection intensity by qPCR cycle threshold was higher in pre-school aged children (Rs = 0.30, p-value 0.03) There was no statistically significant association between STH infection and anaemia (OR 1.0 p = 0.8), stunting (OR 1.9, p-value 0.5) and wasting (OR 2.0, p-value 0.2) in children. This study reveals a persistent reservoir of STH infection across the community, with high rates of anaemia and malnutrition, despite high-coverage of mebendazole mass-drug administration in pre-school children. This reflects the need for a new strategy to soil-transmitted helminth control, to reduce infections and ultimately eliminate transmission.

Baseline patterns of infection in regions of Benin, Malawi and India seeking to interrupt transmission of soil transmitted helminths (STH) in the DeWorm3 trial.

Global efforts to control morbidity associated with soil-transmitted helminth infections (STH) have focused largely on the targeted treatment of high-risk groups, including children and pregnant women. However, it is not clear when such programs can be discontinued and there are concerns about the sustainability of current STH control programs. The DeWorm3 project is a large multi-country community cluster randomized trial in Benin, India and Malawi designed to determine the feasibility of interrupting the transmission of STH using community-wide delivery of mass drug administration (MDA) with anthelmintics over multiple rounds. Here, we present baseline data and estimate key epidemiological parameters important in determining the likelihood of transmission interruption in the DeWorm3 trial. A baseline census was conducted in October-December 2017 in India, November-December 2017 in Malawi and in January-February 2018 in Benin. The baseline census enumerated all members of each household and collected demographic data and information on occupation, assets, and access to water, sanitation and hygiene (WASH). Each study site was divided into 40 clusters of at least 1,650 individuals per cluster. Clusters were randomized to receive twice yearly community-wide MDA with albendazole (GSK) targeting eligible individuals of all ages (20 clusters), or to receive the standard-of-care deworming program targeting children provided in each country. In each site, a randomly selected group of 150 individuals per cluster (6,000 total per site) was selected from the baseline census using stratified random sampling, and each individual provided a single stool sample for analysis of STH infection using the Kato-Katz technique. Study site, household and individual characteristics were summarized as appropriate. We estimated key epidemiological parameters including the force of infection and the degree of parasite aggregation within the population. The DeWorm3 sites range in population from 94,969 to 140,932. The population age distribution varied significantly by site, with the highest proportion of infants and young children in Malawi and the highest proportion of adults in India. The baseline age- and cluster-weighted prevalence, as measured by Kato-Katz, varied across sites and by species, Baseline hookworm prevalence in India was 21.4% (95% CI: 20.4-22.4%), while prevalence of Ascaris and Trichuris by Kato-Katz was low (0.1% and 0.3% overall). In Malawi, the overall age- and cluster-weighted STH prevalence was 7.7% (95% CI: 7.1-8.4%) predominantly driven by hookworm infections (7.4%) while Ascaris (0.1%) and Trichuris (0.3%) infections were rare. In Benin, the overall age- and cluster-weighted prevalence was significantly lower (5.6%, 95% CI: 5.1-6.2%) and Ascaris (2.0%, 95% CI: 1.6-2.3%) was more common than in other sites. Ascaris infections were more likely to be moderate- or heavy-intensity (43.7%, unweighted) compared to hookworm (5.0%). The force of infection for hookworm was highest in adults in India and Malawi but appeared relatively stable across age groups in Benin. These data demonstrate the significant variability between the sites in terms of demography, socio-economic status and environmental characteristics. In addition, the baseline prevalence and intensity data from DeWorm3 suggest that each site has unique epidemiologic characteristics that will be critical in determining correlates of achieving STH transmission interruption in the DeWorm3 trial. Trial registration: The trial was registered at ClinicalTrials.gov (NCT03014167).

Performance of the Kato-Katz method and real time polymerase chain reaction for the diagnosis of soil-transmitted helminthiasis in the framework of a randomised controlled trial: treatment efficacy and day-to-day variation.

BACKGROUND: Accurate, scalable and sensitive diagnostic tools are crucial in determining prevalence of soil-transmitted helminths (STH), assessing infection intensities and monitoring treatment efficacy. However, assessments on treatment efficacy comparing traditional microscopic to newly emerging molecular approaches such as quantitative Polymerase Chain Reaction (qPCR) are scarce and hampered partly by lack of an established diagnostic gold standard. METHODS: We compared the performance of the copromicroscopic Kato-Katz method to qPCR in the framework of a randomized controlled trial on Pemba Island, Tanzania, evaluating treatment efficacy based on cure rates of albendazole monotherapy versus ivermectin-albendazole against Trichuris trichiura and concomitant STH infections. Day-to-day variability of both diagnostic methods was assessed to elucidate reproducibility of test results by analysing two stool samples before and two stool samples after treatment of 160 T. trichiura Kato-Katz positive participants, partially co-infected with Ascaris lumbricoides and hookworm, per treatment arm (n = 320). As negative controls, two faecal samples of 180 Kato-Katz helminth negative participants were analysed. RESULTS: Fair to moderate correlation between microscopic egg count and DNA copy number for the different STH species was observed at baseline and follow-up. Results indicated higher sensitivity of qPCR for all three STH species across all time points; however, we found lower test result reproducibility compared to Kato-Katz. When assessed with two samples from consecutive days by qPCR, cure rates were significantly lower for T. trichiura (23.2 vs 46.8%), A. lumbricoides (75.3 vs 100%) and hookworm (52.4 vs 78.3%) in the ivermectin-albendazole treatment arm, when compared to Kato-Katz. CONCLUSIONS: qPCR diagnosis showed lower reproducibility of test results compared to Kato-Katz, hence multiple samples per participant should be analysed to achieve a reliable diagnosis of STH infection. Our study confirms that cure rates are overestimated using Kato-Katz alone. Our findings emphasize that standardized and accurate molecular diagnostic tools are urgently needed for future monitoring within STH control and/or elimination programmes.

Programmatic implications of the TUMIKIA trial on community-wide treatment for soil-transmitted helminths: further health economic analyses needed before a change in policy.

School-based deworming programmes are currently the main approach used to control the soil-transmitted helminths (STHs). A key unanswered policy question is whether mass drug administration (MDA) should be targeted to the whole community instead, and several trials in this area have been conducted or are currently on-going. A recent well-conducted trial demonstrated that successful community-wide treatment is a feasible strategy for STH control and can be more effective than school-based treatment in reducing prevalence and intensity of hookworm infection. However, we would argue that it is vital that these findings are not taken out of context or over generalised, as the additional health benefits gained from switching to community-wide treatment will vary depending on the STH species and baseline endemicity. Moreover, community-wide treatment will typically be more expensive than school-based treatment. The epidemiological evidence for an additional benefit from a switch to community-wide treatment has yet to be proven to represent "good value for money" across different settings. Further work is needed before changes in policy are made regarding the use of community-wide treatment for STH control, including comprehensive assessments of its additional public health benefits and costs across a range of scenarios, accounting for the presence of alternative treatment delivery platforms.

Contributions of malaria, helminths, HIV and iron deficiency to anaemia in pregnant women attending ante-natal clinic in SouthWest Nigeria.

BACKGROUND: Iron deficiency is a dominant source of anaemia in many settings. To evaluate the key cause of anaemia in the study area, the prevalence of anaemia due to major public health diseases was compared with anaemia due to iron deficiency. METHODS: Pregnant women were recruited from ante-natal (n=490) and HIV clinics (n=217) with their personal data documented using a questionnaire. Microscopy of Giemsa-stained thick smears was used for detection of malaria parasites while helminths in stools were detected using direct smear method. Haematocrit values were determined by capillary method. Serum ferritin levels were determined using enzyme-linked immunosorbent assay. Data was analysed using SPSS version 22.0. RESULTS: The mean age of the recruited women was 28.6±5.4 years old. There were 68.1% cases of anaemia of which 35.5% was due to infections only predominantly HIV and malaria, 14.9% from unknown sources while anaemia due to iron deficiency only was 7.1%. CONCLUSION: It can safely be inferred that malaria and HIV predispose to anaemia than iron deficiency in the study area. Although pregnant women are dewormed and given IPTp for helminths and malaria treatment respectively, there should be complementary routine malaria screening at ANC visits for those with HCT values <33% and those infected with HIV.

A cluster-randomised controlled trial comparing school and community-based deworming for soil transmitted helminth control in school-age children: the CoDe-STH trial protocol.

BACKGROUND: Current guidelines and targets for soil-transmitted helminth (STH) control focus on school-based deworming for school-age children, given the high risk of associated morbidity in this age group. However, expanding deworming to all age groups may achieve improved STH control among both the community in general and school-age children, by reducing their risk of reinfection. This trial aims to compare school-based targeted deworming with community-wide mass deworming in terms of impact on STH infections among school-age children. METHODS: The CoDe-STH (Community Deworming against STH) trial is a cluster-randomised controlled trial (RCT) in 64 primary schools in Dak Lak province, Vietnam. The control arm will receive one round of school-based targeted deworming with albendazole, while in the intervention arm, community-wide mass deworming with albendazole will be implemented alongside school-based deworming. Prevalence of STH infections will be measured in school-age children at baseline and 12 months following deworming. The primary outcome is hookworm prevalence in school-age children at 12 months, by quantitative PCR. Analysis will be intention-to-treat, with outcomes compared between study arms using generalised linear and non-linear mixed models. Additionally, cost-effectiveness of mass and targeted deworming will be calculated and compared, and focus group discussions and interviews will be used to assess acceptability and feasibility of deworming approaches. Individual based stochastic models will be used to predict the impact of mass and targeted deworming strategies beyond the RCT timeframe to assess the likelihood of parasite population 'bounce-back' if deworming is ceased due to low STH prevalence. DISCUSSION: The first large-scale trial comparing mass and targeted deworming for STH control in South East Asia will provide key information for policy makers regarding the optimal design of STH control programs. TRIAL REGISTRATION: ACTRN12619000309189 .

Provision of deworming intervention to pregnant women by antenatal services in countries endemic for soil-transmitted helminthiasis.

BACKGROUND: The World Health Organization has recently reemphasized the importance of providing preventive chemotherapy to women of reproductive age in countries endemic for soil-transmitted helminthiasis as they are at heightened risk of associated morbidity. The Demographic and Health Surveys (DHS) Program is responsible for collecting and disseminating accurate, nationally representative data on health and population in developing countries. Our study aims to estimate the number of pregnant women at risk of soil-transmitted helminthiasis that self-reported deworming by antenatal services in endemic countries that conducted Demographic and Health Surveys. METHODOLOGY/PRINCIPAL FINDINGS: The number of pregnant women living in endemic countries was extrapolated from the United Nations World Population Prospects 2015. National deworming coverage among pregnant women were extracted from Demographic and Health Surveys and applied to total numbers of pregnant women in the country. Sub-national DHS with data on self-reported deworming were available from 49 of the 102 endemic countries. In some regions more than 73% of STH endemic countries had a DHS. The DHS report an average deworming coverage of 23% (CI 19-28), ranging from 2% (CI 1-3) to 35% (CI 29-40) in the different regions, meaning more than 16 million pregnant women were dewormed in countries surveyed by DHS. The deworming rates amongst the 43 million pregnant women in STH endemic countries not surveyed by DHS remains unknown. CONCLUSIONS/SIGNIFICANCE: These estimates will serve to establish baseline numbers of deworming coverage among pregnant women, monitor progress, and urge endemic countries to continue working toward reducing the burden of soil-transmitted helminthiasis. The DHS program should be extended to STH-endemic countries currently not covering the topic of deworming during pregnancy.

A high-throughput sequencing assay to comprehensively detect and characterize unicellular eukaryotes and helminths from biological and environmental samples.

BACKGROUND: Several of the most devastating human diseases are caused by eukaryotic parasites transmitted by arthropod vectors or through food and water contamination. These pathogens only represent a fraction of all unicellular eukaryotes and helminths that are present in the environment and many uncharacterized organisms might have subtle but pervasive effects on health, including by modifying the microbiome where they reside. Unfortunately, while we have modern molecular tools to characterize bacterial and, to a lesser extent, fungal communities, we lack suitable methods to comprehensively investigate and characterize most unicellular eukaryotes and helminths: the detection of these organisms often relies on microscopy that cannot differentiate related organisms, while molecular assays can only detect the pathogens specifically tested. RESULTS: Here, we describe a novel sequencing-based assay, akin to bacterial 16S rRNA sequencing, that enables high-throughput detection and characterization of a wide range of unicellular eukaryotes and helminths, including those from taxonomical groups containing all common human parasites. We designed and evaluated taxon-specific PCR primer pairs that selectively amplify all species from eight taxonomical groups (Apicomplexa, Amoeba, Diplomonadida, Kinetoplastida, Parabasalia, Nematoda, Platyhelminthes, and Microsporidia). We then used these primers to screen DNA extracted from clinical, biological, and environmental samples, and after next-generation sequencing, identified both known and previously undescribed organisms from most taxa targeted. CONCLUSIONS: This novel high-throughput assay enables comprehensive detection and identification of eukaryotic parasites and related organisms, from a wide range of complex biological and environmental samples. This approach can be easily deployed to many settings and will efficiently complement existing methods and provide a holistic perspective on the microbiome.

Removal of helminth eggs by centralized and decentralized wastewater treatment plants in South Africa and Lesotho: health implications for direct and indirect exposure to the effluents.

Wastewater may contain contaminants harmful to human health; hence, there is the need for treatment before discharge. Centralized wastewater treatment systems are the favored treatment options globally, but these are not necessarily superior in reduction of pathogens as compared to decentralized wastewater treatment systems (collectively called DEWATS). This study was therefore undertaken to assess the soil-transmitted helminth (STH) and Taenia sp. egg reduction efficiency of selected anaerobic baffled reactors and planted gravel filters compared to centralized wastewater treatment plants in South Africa and Lesotho. The risk of ascariasis with exposure to effluents from the centralized wastewater treatment plants was also assessed using the quantitative microbial risk assessment (QMRA) approach. Eggs of Ascaris spp., hookworm, Trichuris spp., Taenia spp., and Toxocara spp. were commonly detected in the untreated wastewater. The DEWATS plants removed between 95 and 100% of the STH and Taenia sp. eggs, with centralized plants removing between 67 and 100%. Helminth egg concentrations in the final effluents from the centralized wastewater treatment plants were consistently higher than those in the WHO recommended guideline (≤ 1 helminth egg/L) for agricultural use resulting in higher risk of ascariasis. Therefore, in conclusion, DEWATS plants may be more efficient in reducing the concentration of helminth eggs in wastewater, resulting in lower risks of STH infections upon exposure.

Investigations into the association between soil-transmitted helminth infections, haemoglobin and child development indices in Manufahi District, Timor-Leste.

BACKGROUND: Timor-Leste has a high prevalence of soil-transmitted helminth (STH) infections. High proportions of the population have been reported as being anaemic, and extremely high proportions of children as stunted or wasted. There have been no published analyses of the contributions of STH to these morbidity outcomes in Timor-Leste. METHODS: Using baseline cross-sectional data from 24 communities (18 communities enrolled in a cluster randomised controlled trial, and identically-collected data from six additional communities), analyses of the association between STH infections and community haemoglobin and child development indices were undertaken. Stool samples were assessed for STH using qPCR and participant haemoglobin, heights and weights were measured. Questionnaires were administered to collect demographic and socioeconomic data. Intensity of infection was categorised using correlational analysis between qPCR quantification cycle values and eggs per gram of faeces equivalents, with algorithms generated from seeding experiments. Mixed-effects logistic and multinomial regression were used to assess the association between STH infection intensity classes and anaemia, and child stunting, wasting and underweight. RESULTS: Very high stunting (60%), underweight (60%), and wasting (20%) in children, but low anaemia prevalence (15%), were found in the study communities. STH were not significantly associated with morbidity outcomes. Male children and those in the poorest socioeconomic quintile were significantly more likely to be moderately and severely stunted. Male children were significantly more likely than female children to be severely underweight. Increasing age was also a risk factor for being underweight. Few risk factors emerged for wasting in these analyses. CONCLUSIONS: According to World Health Organization international reference standards, levels of child morbidity in this population constitute a public health emergency, although the international reference standards need to be critically evaluated for their applicability in Timor-Leste. Strategies to improve child development and morbidity outcomes, for example via nutrition and iron supplementation programmes, are recommended for these communities. Despite the apparent lack of an association from STH in driving anaemia, stunting, wasting and underweight, high endemicity suggests a need for STH control strategies. TRIAL REGISTRATION: Australian and New Zealand Clinical Trials Registry ACTRN12614000680662 ; retrospectively registered.

Human parasites in the Roman World: health consequences of conquering an empire.

The archaeological evidence for parasites in the Roman era is presented in order to demonstrate the species present at that time, and highlight the health consequences for people living under Roman rule. Despite their large multi-seat public latrines with washing facilities, sewer systems, sanitation legislation, fountains and piped drinking water from aqueducts, we see the widespread presence of whipworm (Trichuris trichiura), roundworm (Ascaris lumbricoides) and Entamoeba histolytica that causes dysentery. This would suggest that the public sanitation measures were insufficient to protect the population from parasites spread by fecal contamination. Ectoparasites such as fleas, head lice, body lice, pubic lice and bed bugs were also present, and delousing combs have been found. The evidence fails to demonstrate that the Roman culture of regular bathing in the public baths reduced the prevalence of these parasites. Fish tapeworm was noted to be widely present, and was more common than in Bronze and Iron Age Europe. It is possible that the Roman enthusiasm for fermented, uncooked fish sauce (garum) may have facilitated the spread of this helminth. Roman medical practitioners such as Galen were aware of intestinal worms, explaining their existence and planning treatment using the humoural theory of the period.

Ancient Human Parasites in Ethnic Chinese Populations.

Whilst archaeological evidence for many aspects of life in ancient China is well studied, there has been much less interest in ancient infectious diseases, such as intestinal parasites in past Chinese populations. Here, we bring together evidence from mummies, ancient latrines, and pelvic soil from burials, dating from the Neolithic Period to the Qing Dynasty, in order to better understand the health of the past inhabitants of China and the diseases endemic in the region. Seven species of intestinal parasite have been identified, namely roundworm, whipworm, Chinese liver fluke, oriental schistosome, pinworm, Taenia sp. tapeworm, and the intestinal fluke Fasciolopsis buski. It was found that in the past, roundworm, whipworm, and Chinese liver fluke appear to have been much more common than the other species. While roundworm and whipworm remained common into the late 20th century, Chinese liver fluke seems to have undergone a marked decline in its prevalence over time. The iconic transport route known as the Silk Road has been shown to have acted as a vector for the transmission of ancient diseases, highlighted by the discovery of Chinese liver fluke in a 2,000 year-old relay station in northwest China, 1,500 km outside its endemic range.

Distribution of infective gastrointestinal helminth larvae in tropical erect grass under different feeding systems for lambs.

This study examined tropical pasture contamination dynamics under different feeding systems for finishing lambs. The experiment aimed to evaluate the vertical distribution of gastrointestinal helminth infective larvae (L3) in erect grass subjected to grazing and to assess the parasite load and its impact on lamb performance in three production systems. Three treatments based on Aruana grass (Panicum maximum cv. IZ-5) were as follows: T1, grass only; T2, grass with 1.5% of body weight (BW) nutrient concentrate supplementation; and T3, grass with 2.5% BW concentrate supplementation. The randomized block design had three replicates of three treatments, with six lambs per replicate. L3 were recovered from three pasture strata (upper, middle, and bottom), each representing one third of the sward height, and correlated with microclimatic data. Significant differences (P < 0.05) were observed among treatments in the L3 recovery. Despite different grass heights between treatments and microclimates within the sward, the L3 concentration generally did not differ significantly among the three strata within a treatment (P > 0.05). Pasture microclimate did not correlate with larval recovery. At the end of the experiment, the animal fecal egg count was similar among treatments (P > 0.05). The results indicated that different lamb feeding systems in a tropical erect grassland caused differences in grass height but did not affect the distribution of infective larvae among strata. Larvae were found from the base to the top of the grass sward.

Therapeutic efficacy of different brands of albendazole against soil transmitted helminths among students of Mendera Elementary School, Jimma, Southwest Ethiopia.

INTRODUCTION: Different brands Albendazole are commercially available and the efficacious brand/s is/are required for effective control of STHs infection. Thus, this study is aimed at determining the therapeutic efficacy of different brands of albendazole against soil transmitted helminths among school children of Jimma town. METHODS: A cross sectional survey for prevalence of geohelminths and a randomized trial for efficacy study of different brands of albendazole was conducted among students Mendera Elementary School from March 29 to April 29, 2010. Positive subjects were randomized into three treatment arms using lottery method. The collected stool samples were examined by the McMaster method. CRs were calculated using SPSS windows version 16 and ERRs were calculated using appropriate formula. RESULTS: Of the 715 school children who had their stools examined, 326 were positive for STHs with a prevalence rate of 45.6%. The cure rates (CR) for A. lumbricoides, T. trichiura and Hookworm were 99.4, 59.9 and 93.7%, respectively. Similarly, the egg reduction rates (ERR) were 97, 99.9 and 99.9% respectively. A statistical significant mean STH egg count difference were observed between pre and post-intervention study (p <0.001). But no statistical significant curing effect difference were observed among the three brands used against the three STHs (p >0.05). CONCLUSION: All the three brands of Albendazole tested regardless of the brand type were therapeutically efficacious for Ascariasis, Trichuriasis and Hookworm infections irrespective of the infection status whether it was single or multiple.

Diagnostic accuracy and cost-effectiveness of alternative methods for detection of soil-transmitted helminths in a post-treatment setting in western Kenya.

OBJECTIVES: This study evaluates the diagnostic accuracy and cost-effectiveness of the Kato-Katz and Mini-FLOTAC methods for detection of soil-transmitted helminths (STH) in a post-treatment setting in western Kenya. A cost analysis also explores the cost implications of collecting samples during school surveys when compared to household surveys. METHODS: Stool samples were collected from children (n = 652) attending 18 schools in Bungoma County and diagnosed by the Kato-Katz and Mini-FLOTAC coprological methods. Sensitivity and additional diagnostic performance measures were analyzed using Bayesian latent class modeling. Financial and economic costs were calculated for all survey and diagnostic activities, and cost per child tested, cost per case detected and cost per STH infection correctly classified were estimated. A sensitivity analysis was conducted to assess the impact of various survey parameters on cost estimates. RESULTS: Both diagnostic methods exhibited comparable sensitivity for detection of any STH species over single and consecutive day sampling: 52.0% for single day Kato-Katz; 49.1% for single-day Mini-FLOTAC; 76.9% for consecutive day Kato-Katz; and 74.1% for consecutive day Mini-FLOTAC. Diagnostic performance did not differ significantly between methods for the different STH species. Use of Kato-Katz with school-based sampling was the lowest cost scenario for cost per child tested ($10.14) and cost per case correctly classified ($12.84). Cost per case detected was lowest for Kato-Katz used in community-based sampling ($128.24). Sensitivity analysis revealed the cost of case detection for any STH decreased non-linearly as prevalence rates increased and was influenced by the number of samples collected. CONCLUSIONS: The Kato-Katz method was comparable in diagnostic sensitivity to the Mini-FLOTAC method, but afforded greater cost-effectiveness. Future work is required to evaluate the cost-effectiveness of STH surveillance in different settings.

Soluções de alho (Allium sativum L. ) no controle de nematódeos gastrintestinais em bovinos jovens da raça Holandesa / Garlic (Allium sativum L. ) solutions in control of gastrointestinal nematodes in young Holstein cattle

Para avaliar o efeito da atividade anti-helmíntica do alho suplementado, foram utilizadas 24 bezerras e novilhas da raça Holandesa, naturalmente infectadas. As soluções foram preparadas triturando-se o alho, (50%), mais água ou álcool 92º, (50%), administrando-se oralmente aos animais. Os tratamentos (T) foram constituídos pelo grupo controle negativo (T1); extrato alcoólico de alho a 60g e 120g/100Kg de peso vivo (T2) e (T3); extrato aquoso de alho a 60 e 120g/100kg de peso vivo (T4) e (T5); e o grupo controle positivo com albendazol a 10% (T6). Os tratamentos fitoterápicos foram repetidos a cada 14 dias, caso a infecção fosse superior a 400 ovos por grama de fezes (OPG). A técnica de coprocultura quantitativa e qualitativa foi empregada para avaliar a eficácia anti-helmíntica dos tratamentos. Foram observadas diferenças entre os grupos controle e tratados para OPG e na porcentagem relativa de larvas infectantes e desenvolvimento larval. O uso das soluções de alho demonstrou controle parcial de nematódeos gastrintestinais.

Twenty four Holstein calves and heifers naturally infected were used to evaluate the effect of garlic supply on helminth control. The solutions consisted to triturated garlic, (50%), plus water or alcohol 92º, (50%), orally-administrable on the animals. Treatments (T) consisted of a negative control (T1), garlic at 60 (T2) and 120g on alcoholic extract (T3); 60 (T4) and 120g on aqueous extract/100kg of life weight (T5) and the positive control with albendazol at 10% (T6). The phytotherapic treatments were repeated after 14th day if the infection was superior to 400 eggs per gram of faeces (EPG). The quantitative and qualitative coproculture technique was performed to evaluate the anthelmintic efficacy of the treatments. Differences between treated and control groups were observed in EPG and in relative percentage of infective larvae and the larval development. Partial control was found with the garlic solutions on gastrointestinal nematodes.

Helminths of wild hybrid marmosets (Callithrix sp.) living in an environment with high human activity / Helmintos de saguis (Callithrix sp.) híbridos de vida livre vivendo em ambientes com alta atividade humana

The objective of this study was to identify the helminth fauna in hybrid, non-native marmosets, through analysis of fecal samples. The study involved 51 marmosets (genus Callithrix) from five groups living in places with levels of human impact in Viçosa-MG. The marmosets were caught using a multiple-entrance trap and were anaesthetized. Feces were collected, refrigerated and analyzed by means of the sedimentation technique (Hoffmann-Pons-Janner). Eggs and parasites were identified, but not counted. Most of the marmosets (86%) were parasitized by at least one genus of helminths. Among the infected marmosets, 37% presented co-infection. The intestinal helminths comprised four different taxa: Primasubulura jacchi, Ancylostomatidae, Prosthenorchis sp. and Dilepididae.P. jacchi and Ancylostomatidae had higher prevalences (> 80% and > 40%, respectively) and were found in all marmoset groups. Dilepididae species were found in almost all the groups, but only accounted for around 30% of the marmosets. Prosthenorchis sp. showed a relatively low prevalence (< 10%) and was only found in one group. Although two parasites are commonly found in marmosets and other primates (P. jacchi and Prosthenorchis sp.), our study is the first record for Ancylostomatidae and Dilepididae. Factors like marmosets' feeding behavior and their contact with humans and other species of nonhuman primates seem to be determinants of infection among marmosets.

O objetivo do presente estudo foi a identificação da helmintofauna em saguis híbridos e introduzidos, por meio de análises de amostras fecais. O estudo envolveu 51 saguis do gênero Callithrix, de cinco grupos que ocupam áreas com diferentes impactos humanos. Os saguis foram capturados com armadilha de múltiplas entradas e anestesiados. Fezes foram colhidas, refrigeradas e analisadas pela técnica de sedimentação (Hoffmann-Pons-Janner). Ovos e parasitas foram identificados, mas não contados. A maior parte dos saguis (86%) estava parasitado por, pelo menos, uma espécie de helminto. Do grupo infectado, 37% apresentou coinfecção. A diversidade helmíntica intestinal incluiu quatro táxons diferentes: Primasubulura jacchi, Ancylostomatidae, Prosthenorchis sp. e Dilepididae. P. jacchi e Ancylostomatidae apresentaram as maiores prevalências (> 80% e > 40%, respectivamente) e foram encontrados em todos os grupos. As espécies de Dilepididae apresentaram aproximadamente 30% da prevalência e foram encontrados em quase todos os grupos. A espécie Prosthenorchis sp. apresentou prevalência relativamente baixa (< 10%) e foi encontrado somente em um grupo. Considerando que duas das espécies são parasitas comumente descritos para saguis e primatas (P. jacchi e Prosthenorchis sp.), este estudo consiste no primeiro registro para Ancylostomatidae e Dilepididae. Fatores como o comportamento alimentar e o contato com o homem e outras espécies de primatas não humanos, parecem ser determinantes na contaminação dos saguis.