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One Health surveillance involves the analysis of human, animal and environmental samples, recognising their interconnectedness in health systems. Such considerations are crucial to investigate the transmission of many pathogens, including drug-resistant bacteria and parasites. The highest rates of antimicrobial resistance (AMR)-associated deaths are observed in sub-Saharan Africa, where concurrently the waterborne parasitic disease schistosomiasis can be highly endemic in both humans and animals. Although there is growing acknowledgment of significant interactions between bacteria and parasites, knowledge of relationships between schistosomes, microbes and AMR remains inadequate. In addition, newly emergent research has revealed the previously underappreciated roles of animals and the environment in both AMR and schistosomiasis transmission. We consider shared environmental drivers and colonisation linkage in this narrative review, with a focus on extended-spectrum beta-lactamase-mediated resistance among bacteria from the Enterobacteriaceae family, which is exceedingly prevalent and responsible for a high burden of AMR-associated deaths. Then we examine novel findings from Malawi, where the landscapes of AMR and schistosomiasis are rapidly evolving, and make comparisons to other geographic areas with similar co-infection epidemiology. We identify several knowledge gaps that could be addressed in future research, including the need to characterise the impact of intestinal schistosomiasis and freshwater contact on intestinal AMR colonisation, before proposing a rationale for connecting AMR surveillance and schistosomiasis research within a One Health framework. [ABSTRACT FROM AUTHOR]

The Great African Lakes in Uganda (Lake Albert and Lake Victoria) are known habitats to several sympatric species of Biomphalaria , intermediate snail hosts of the human parasite Schistosoma mansoni. However, accurate identification of snails by morphology alone can be problematic, highlighting a need for robust, on-site identification methods, since only certain species have important roles in parasite transmission. This study investigates the conchological variation within Biomphalaria species collected from these two Great East African Lakes. We compared the shell morphologies of Biomphalaria species using landmark-based morphometric techniques and were able to distinguish Biomphalaria species through canonical variate analysis (CVA) of the apical and apertural shell angles. After identification with molecular methods, three Biomphalaria species (B. pfeifferi , B. stanleyi , and B. sudanica), with heterogenous occurrences along the shoreline, were identified at Lake Albert that could be differentiated from one another using CVA of apical and apertural datasets; by contrast, a single Biomphalaria species was identified at Lake Victoria (B. choanomphala). When snails from both lakes were compared together, CVA was able to differentiate all four species using the apical dataset but not the apertural dataset. Of the Biomphalaria species identified, ecological phenotypic variation was only found in B. choanomphala , which exhibited two distinct ecological morphotypes. Furthermore, these two B. choanomphala morphotypes from Lake Victoria overlapped upon analysis of the apical dataset, yet were clearly separated upon analysis of the apertural dataset. Our study demonstrates that landmark-based morphometrics could play a future role in distinguishing sympatric Biomphalaria species in Uganda. [ABSTRACT FROM AUTHOR]

Background Complications of urogenital schistosomiasis include acute inflammatory and chronic fibrotic changes within the urogenital tract. Disease burden of this neglected tropical disease is often underestimated, as only active, urine egg-patent Schistosoma infection is formally considered. Previous studies have focussed on short-term effects of praziquantel treatment on urinary tract pathology, demonstrating that acute inflammation is reversible. However, the reversibility of chronic changes is less well studied. Methods Our study compared, at two time points 14 y apart, urine egg-patent infection and urinary tract pathology in a cohort of women living in a highly endemic area having intermittent praziquantel treatment(s). In 2014 we matched 93 women to their findings in a previous study in 2000. Results Between 2000 and 2014 the rate of egg-patent infection decreased from 34% (95% confidence interval [CI] 25 to 44) to 9% (95% CI 3 to 14). However, urinary tract pathology increased from 15% (95% CI 8 to 22) to 19% (95% CI 11 to 27), with the greatest increase seen in bladder thickening and shape abnormality. Conclusions Despite praziquantel treatment, fibrosis from chronic schistosomiasis outlasts the presence of active infection, continuing to cause lasting morbidity. We suggest that future efforts to eliminate persistent morbidity attributable to schistosomiasis should include intensified disease management. [ABSTRACT FROM AUTHOR]

Background A cross-sectional survey was performed to estimate the prevalence of periportal fibrosis in children based on ultrasound examination in the Marolambo district of the Atsinanana region of Madagascar. This is a remote area known to have a high prevalence of intestinal schistosomiasis. Methods School-aged children (5–14 y) were selected from six villages for parasitological and sonographic examination. Circulating cathodic antigen (CCA) tests and Kato Katz (KK) stool microscopy were performed. Video-clips of liver views were recorded with a SonoSite iViz and interpreted in the UK by comparison with standardised images (WHO protocol). Results The prevalence of schistosomiasis according to CCA testing was 97.8% (269/275) and 73.8% (203/275) by KK. Sonographic evidence of periportal fibrosis was observed in 11.3% (31/275). The youngest children with fibrosis were aged 6 y. Fibrosis was more common in older children (p=0.03) but was not associated with either infection intensity category (p=0.07) or gender (p=0.67). Conclusions Findings of periportal fibrosis among children in these hard-to-reach villages suggests chronic Schistosoma mansoni infection from a very young age. This may reflect other similarly remote schistosomiasis-endemic areas and reinforces the need to investigate morbidity in neglected communities to understand the true extent of disease burden in endemic countries. [ABSTRACT FROM AUTHOR]

Background Barombi Kotto, Cameroon serves as a reference location for assessing intervention strategies against Schistosoma haematobium. Methods As part of a pilot study, the whole community was treated with praziquantel, inclusive of pre-school-age children (PSAC) and their mothers. One year later, egg-patent infections were reassessed and water contact patterns of 12 pairs of PSAC and their mothers were measured with global positioning system (GPS) data loggers. Results A substantial reduction in general infection prevalence, from 44.8% to 12.2%, was observed but certain PSAC and mothers continued to have egg-patent infections. Analysis of GPS data demonstrated similar water contact levels between the child and mother groups, although certain individuals were numerical outliers. Conclusions This study shows the potential of GPS data loggers to clarify the at-risk status of PSAC and mothers. [ABSTRACT FROM AUTHOR]

As part of a longitudinal cohort investigation of intestinal schistosomiasis and malaria in Ugandan children and their mothers on the shorelines of Lakes Victoria and Albert, we documented risk factors and morbidity associated with nonfalciparum Plasmodium infections and the longitudinal dynamics of Plasmodium species in children. Host age, household location, and Plasmodium falciparum infection were strongly associated with nonfalciparum Plasmodium infections, and Plasmodium malariae infection was associated with splenomegaly. Despite regular artemisinin combination therapy treatment, there was a 3-fold rise in P. malariae prevalence, which was not accountable for by increasing age of the child. Worryingly, our findings reveal the consistent emergence of nonfalciparum infections in children, highlighting the complex dynamics underlying multispecies infections here. Given the growing body of evidence that nonfalciparum malaria infections cause significant morbidity, we encourage better surveillance for nonfalciparum Plasmodium infections, particularly in children, with more sensitive DNA detection methods and improved field-based diagnostics. [ABSTRACT FROM AUTHOR]

Background: In endemic areas, schistosomiasis causes both overt and subclinical disease in young children and their mothers, as well as in returned travellers. Sources of data: Key recently published literature. Areas of agreement: An action plan for paediatric schistosomiasis and female genital schistosomiasis (FGS) is needed with expanded access to praziquantel (PZQ) treatment required. Areas of controversy: Schistosomiasis-related morbidity is underappreciated. Present and future demand for PZQ treatment is bottlenecked, imbalanced and inequitable. Current dosing, treatment algorithms and access plans are suboptimal with treatment stalled during pregnancy. Growing points: Raised dosing of PZQ (>40 mg/kg) is being explored in young children. Surveillance of female genital schistosomiasis FGS is increasing. Use of PZQ in pregnancy is safe and preventive chemotherapy guidelines are being revised in morbidity- and transmission-control settings. Areas timely for developing research: Shifting focus of population-level control to individual-case management. Detection and prevention of FGS within general health services and integration of PZQ treatment for women and children in antenatal clinics. Feasibility studies assessing alternative and expanded access to PZQ treatment to at-risk children and mothers and pregnant women. [ABSTRACT FROM AUTHOR]

Background: Water-borne parasitic diseases associated with poverty still blight the lives of African school children. In Uganda, intestinal schistosomiasis is still common along the shoreline of Lake Albert, despite ongoing control, and co-infection with giardiasis and malaria is poorly described. To shed light on putative interactions between diseases, a prospective cross-sectional parasitological survey was undertaken in five primary schools. Methods: Stool samples from 254 school children, aged 5-10 years, were examined by microscopy and rapid diagnostic tests (RDTs), with additional real-time PCR assays for detection of Giardia DNA. A finger-prick blood sample was also taken from each child and tested for malaria, and haemoblobin levels measured. Assocations between diseases and anaemia were assessed. Results: Intestinal schistosomiasis (46.5%), giardiasis (41.6%) and malaria (56.2%) were common, and a quarter of children were anaemic (<115 g/L). Up to 87.0% of children were excreting Giardia DNA and the prevalence of heavy infection by real-time PCR (Ct⩽19) was 19.5%, being positively associated with light, moderate and heavy egg-patent schistosomiasis, as well as with anaemia. Conclusions: In this setting, an extensive burden of giardiasis was revealed with heavy intensity infections associated with egg-patent intestinal schistosomiasis and anaemia. To improve child health, greater attention on giardiasis is needed along with exploring joined-up actions across diseases that promote better water hygiene and sanitation measures. [ABSTRACT FROM AUTHOR]

The article focuses on a study which used a set of molecular DNA detection tools to determine presence of various species of schistosome worms within a cohort of returned Belgian travelers who were examined to a certain degree of advanced diagnostic scrutiny. The reason for withholding prompt treatment of acute schistosomiasis until two to three months later is to allow sufficient time for juvenile schistosomes to mature. Clinical presentations of acute schistosomiasis are described.

Background. The roundworm Ascaris lumbricoides infects 0.8 billion people worldwide, and Ascaris suum infects innumerable pigs across the globe. The extent of natural cross-transmission of Ascaris between pig and human hosts in different geographical settings is unknown, warranting investigation.Methods. Adult Ascaris organisms were obtained from humans and pigs in Europe, Africa, Asia, and Latin America. Barcodes were assigned to 536 parasites on the basis of sequence analysis of the mitochondrial cytochrome c oxidase I gene. Genotyping of 410 worms was also conducted using a panel of microsatellite markers. Phylogenetic, population genetic, and Bayesian assignment methods were used for analysis.Results. There was marked genetic segregation between worms originating from human hosts and those originating from pig hosts. However, human Ascaris infections in Europe were of pig origin, and there was evidence of cross-transmission between humans and pigs in Africa. Significant genetic differentiation exists between parasite populations from different countries, villages, and hosts.Conclusions. In conducting an analysis of variation within Ascaris populations from pig and human hosts across the globe, we demonstrate that cross-transmission takes place in developing and developed countries, contingent upon epidemiological potential and local phylogeography. Our results provide novel insights into the transmission dynamics and speciation of Ascaris worms from humans and pigs that are of importance for control programs. [ABSTRACT FROM AUTHOR]

Background A sensitive and reliable rapid diagnostic test (RDT) which should have comparable diagnostic performance against reference host serological methods is urgently needed for use in point-of-care (POC) diagnosis of intestinal schistosomiasis in pre school-aged children. Methods The diagnostic accuracy of a RDT incorporating Schistosoma mansoni cercarial transformation fluid (SmCTF) for anti-schistosome antibody detection was evaluated with serum samples from a cohort of children from Uganda: 42 children aged under the age of 3 years and 40 children aged between 3 and 5 years. The infection status of these children had been previously determined by inspection of quadruplicate Kato-Katz faecal smears, a single urine circulating cathodic antigen (CCA) dipstick and antibody titres to S. mansoni soluble egg antigen (SmSEA) with a commercially available ELISA. Results Upon comparison with quadruplicate Kato-Katz the sensitivity and specificity of the RDT were 75.7% and 31.1%, respectively. When using the SmSEA-ELISA as an alternate reference test, the RDT achieved 81.3% sensitivity and 61.1% specificity. Sensitivity and specificity compared to the urine-CCA test was 74.5% and 32.3% respectively. Sensitivity differed significantly according to age group. Conclusions The performance of the RDT within this study appeared favourable when compared with the currently-available SmSEA-ELISA. Looking to the future a serological POC test would be particularly promising for use in disease mapping in younger children especially in guiding administration of praziquantel treatment in selective treatment settings. [ABSTRACT FROM AUTHOR]

There is little evidence of transfusion-transmitted malaria (TTM) in malaria-endemic regions. A 2% incidence of TTM found in this study shows that TTM occurs infrequently among recipients of blood transfusion living in a malaria-endemic region.Background. In sub-Saharan Africa, the prevalence of malaria parasitemia in blood donors varies from 0.6% to 50%. Although the burden of TTM in malaria-endemic countries is unknown, it is recommended that all donated blood is screened for malaria parasites. This study aimed to establish the incidence of TTM and identify a suitable screening test.Methods. Pregnant women, children, and immunocompromised malaria-negative transfusion recipients in a teaching hospital in Ghana were recruited over the course of 1 year. Parasites detected in recipients within 14 days of the transfusion were genotyped and compared to parasites in the transfused blood. The presence of genotypically identical parasites in the recipient and the transfused blood confirmed transfusion-transmitted malaria. Four malaria screening tests were compared to assess their usefulness in the context of African blood banks.Results. Of the 50 patients who received transfusions that were positive for Plasmodium falciparum by polymerase chain reaction (PCR), 7 recipients developed PCR-detectable parasitemia. In only 1 of the 50 recipients (2%) was the parasite identical to that in the transfused blood. The prevalence of P. falciparum malaria in transfused blood was 4.7% (21/445) by microscopy, 13.7% (60/440) by rapid diagnostic test, 18% (78/436) by PCR, and 22.2% (98/442) by enzyme immunoassay.Conclusions. Although malaria parasites are commonly detected in blood donors in malaria-endemic areas, transfusion-transmitted malaria occurs infrequently. Policies recommend screening blood donors for malaria, but none of the commonly used methods is sufficiently sensitive to be used by blood banks in malaria-endemic countries. [ABSTRACT FROM AUTHOR]

Specific immunoglobulin E (IgE) responses are upregulated during chronic schistosome infection and during allergy. These responses are tightly regulated during schistosomiasis. We have previously shown that IgE regulation depends on the extent and length of exposure to individual parasite allergen-like proteins. Here we compare the development of IgE and immunoglobulin G4 (IgG4) responses to the differentially expressed allergen-like proteins SmTAL1 and SmTAL2 among preschool-aged children from 2 villages with different levels of Schistosoma mansoni transmission. We found a lack of SmTAL1 responsiveness among all children, but evidence for IgG4-dependent IgE-SmTAL2 desensitization in both villages, occurring earlier among children from the village where the level of transmission was greater. Findings provide insights into the development and regulation of allergic-type immune responses. [ABSTRACT FROM AUTHOR]

Summary: To facilitate administration of praziquantel (PZQ) to African infants and preschool-aged children using a dose pole, the performance of two downwardly extended versions (the first created in 2010 using biometric data from Uganda alone and the second version created here using data from 36 countries) was assessed against height/weight data from a total of 166210 preschool-aged children (≤6 year olds) from 36 African countries. New and optimized thresholds for PZQ tablet administration at one tablet (600mg), ¾ and ½ tablet divisions are suggested here. Both dose poles investigated estimated an acceptable PZQ dosage (30–60mg/Kg) for more than 95% of children. Extension and optimization of the current PZQ dose pole, followed by theoretical validation using biometric data from preschool-aged children (0–6 years of age, 60–110cm in height) from 36 African countries will help future mass drug administration campaigns incorporate younger children. This newly optimized dose pole with single 600mg (height: 99–110cm), ¾ (height: 83–99cm) and ½ (height: 66–83cm) tablet divisions, also reduces drug waste and facilitates inclusion of preschool-aged children. Our findings also have bearings on the use of other dose poles for treatment of young children. [ABSTRACT FROM AUTHOR]

Abstract: Despite the common occurrence of ascariasis in southwestern Uganda, helminth control in the region has been limited. To gain further insights into the genetic diversity of Ascaris in this area, a parasitological survey in mothers (n=41) and children (n=74) living in two villages, Habutobere and Musezero, was carried out. Adult Ascaris worms were collected from infected individuals by chemo-expulsion using pyrantel pamoate treatment. Genetic diversity within these worms was assessed by inspection of DNA sequence variation in a mitochondrial marker and length polymorphism at microsatellite loci. Overall prevalence of ascariasis was 42.5% in mothers and 30.4% in their children and a total of 98 worms was examined from 18 hosts. Sequence analysis of a portion of the mitochondrial cytochrome c oxidase subunit 1 gene revealed 19 different haplotypes, 13 of which had not been previously encountered. Microsatellite analysis using eight loci provided evidence for high gene flow between worm populations from the two villages but comparing these worms with others obtained in a prior study on Unguja, Zanzibar, confirmed little genetic exchange and mixing of worm populations between the two areas. By adding to our understanding of the genetic diversity of Ascaris in Africa, this study provides useful information for monitoring changes in parasite population structure in the face of ongoing and future control. [Copyright &y& Elsevier]

Summary: Point-prevalence recording of the distribution of tropical parasitic diseases at village level is usually sufficient for general monitoring and surveillance. Whilst within-village spatial patterning of diseases exists, and can be important, mapping infected cases in a household-by-household setting is arduous and time consuming. With the development of low-cost GPS-data loggers (< £40) and available GoogleEarthTM satellite imagery, we present a field-applicable method based on crowdsourcing for rapid identification of infected cases (intestinal schistosomiasis, malaria and hookworm) by household. A total of 126 mothers with their 247 preschool children from Bukoba village (Mayuge District, Uganda) were examined with half of these mothers given a GPS-data logger to walk home with, returning the unit the same day for data off-loading, after which, households were assigned GPS coordinates. A satellite image of Bukoba was annotated with households denoting the infection status of each mother and child. General prevalence of intestinal schistosomiasis, malaria and hookworm in mothers and children was: 27.2 vs 7.7%, 28.6 vs 87.0% and 60.0 vs 22.3%, respectively. Different spatial patterns of disease could be identified likely representing the intrinsic differences in parasite biology and interplay with human behaviour(s) across this local landscape providing a better insight into reasons for disease micro-patterning. [ABSTRACT FROM AUTHOR]

Abstract: Ascariasis is of public health importance on the islands of Zanzibar (Unguja and Pemba). To shed light on the molecular epidemiology of this parasite, 68 Ascaris worms, obtained from 14 individuals in four Ungujan villages, were examined by isoenzyme analysis (ISA), DNA barcoding and microsatellite DNA profiling. ISA revealed genetic variation, which was confirmed by DNA barcoding. Nineteen worms recovered from individuals in Uganda were included for comparison. Sixteen unique DNA barcodes were identified, 15 on Unguja and three in Uganda with two shared between. These two barcodes were found in all four Ungujan villages. Worms from Tumbatu-Jongowe, an isolated village on an islet off Unguja, seemed particularly diverse. Within our barcodes, three exact matches were found with Chinese Ascaris retrieved from pigs, which is perhaps surprising given the present rarity of these animals on Unguja. Microsatellite profiling and population genetic analysis revealed further genetic diversity within our samples although population sub-structuring within Unguja was minor in comparison to that between Unguja and Uganda. As African Ascaris has not been subjected to detailed molecular scrutiny, this new diversity represents an important piece in its evolutionary jigsaw and such population markers are informative in monitoring worm dynamics during ongoing control. [Copyright &y& Elsevier]

Background. Single-dose albendazole and mebendazole show limited efficacy in the treatment of trichuriasis. The combination of albendazole with ivermectin improves efficacy, but a mebendazole-ivermectin combination has not been previously investigated. Methods. We performed a randomized controlled trial in 2 schools in Zanzibar, Tanzania, to assess the efficacy and safety of albendazole (400 mg) plus placebo, albendazole plus ivermectin (200 mg/kg), mebendazole (500 mg) plus placebo, and mebendazole plus ivermectin in children with a parasitologically confirmed Trichuris trichiura infection. Cure rate (CR) and egg reduction rate were assessed by intent-to-treat analysis. Adverse events were monitored within 48 h after treatment. Results. Complete data records were available for 548 children. The highest CR against T. trichiura was achieved with a mebendazole-ivermectin combination (55%). Low CRs were observed with albendazole-ivermectin (38%), mebendazole (19%), and albendazole (10%). Compared with placebo, the use of ivermectin statistically significantly increased the CRs from 14% to 47% (odds ratio, 0.19; 95% confidence interval [CI], 0.12-0.28). The highest egg reduction rate (97%; 95% CI, 95%-98%) was observed using the mebendazole-ivermectin combination, followed by albendazole-ivermectin (91%; 95% CI, 87%-94%), mebendazole (67%; 95% CI, 52%-77%), and albendazole (40%; 95% CI, 22%-56%). The adverse events, reported by 136 children, were generally mild, with no significant difference between the treatment arms. Conclusions. Addition of ivermectin improves the therapeutic outcomes of both albendazole and mebendazole against T. trichiura and may be considered for use in soil-transmitted helminth control programs and individual patient management. [ABSTRACT FROM AUTHOR]

Summary: The Ugandan national control programme for schistosomiasis has no clear policy for inclusion of preschool-children (≤5 years old) children. To re-balance this health inequality, we sought to identify best diagnosis of intestinal schistosomiasis, observe treatment safety and efficacy of praziquantel (PZQ), and extend the current WHO dose pole for chemotherapy. We examined and treated 363 preschool children from shoreline villages of Lakes Albert and Victoria, and found that 62·3% (CI95 57·1–67·3) of the children were confirmed to have intestinal schistosomiasis. One day after treatment, children were reported as having headaches (3·6%), vomiting (9·4%), diarrhoea (10·9%) and urticaria/rash (8·9%) with amelioration at 21-day follow-up, where the parasitological cure rate was found to be 100·0%. Height and weight data were collected from a further 3303 preschool children to establish and validate an extended PZQ dose pole that now includes two new height-intervals: 60–84cm for one-half tablet and 84–99cm for three-quarter tablet divisions; which would result in 97·6% of children receiving an acceptable dose (30–60mg/kg). To conclude, preschool children in lakeshore communities of Uganda are at significant risk of intestinal schistosomiasis; we now strongly advocate for their immediate inclusion within the national control programme to eliminate this health inequity. [Copyright &y& Elsevier]

Summary: There is a tendency to neglect diagnostic issues in the era of ‘preventive chemotherapy’ in human helminthiases. However, accurate diagnosis cannot be overemphasized for adequate patient management and monitoring of community-based control programmes. Implicit is a diagnostic dilemma: the more effective interventions are in reducing helminth egg excretion, the less sensitive direct parasitological tests become. Here, experiences gained thus far with the FLOTAC technique for diagnosing common soil-transmitted helminth infections are summarized. A single FLOTAC has higher sensitivity than multiple Kato–Katz thick smears in detecting low-intensity infections. Further validation of the FLOTAC technique in different epidemiological settings is warranted, including diagnosis of intestinal schistosomiasis and food-borne trematodiases. [Copyright &y& Elsevier]

Summary: As part of a 4-year control programme beginning in 2003 and entitled Piga Vita Kichocho, around 140 000 school-aged children on Unguja Island, Zanzibar were treated annually with a combination of praziquantel and albendazole. To provide information on the impact of this intervention, a subset of children, originating from 24 sentinel schools, were monitored in 2004, 2005 and 2006 using both parasitological and behavioural questionnaire methods. Overall, prevalence of urinary schistosomiasis fell by 52%, intensity by 55% and gross haematuria by 82%. There was a positive and statistically significant correlation between areas of elevated disease prevalence and areas of predicted high transmission based upon local occurrence of the permissive intermediate snail host. In areas of low transmission, urinary schistosomiasis was greatly reduced, but, by contrast, other intervention strategies are needed to complement and synergise with chemotherapy in high transmission areas. Whereas significant reductions were documented in the prevalence of both Trichuris trichiura and hookworm, prevalence of Ascaris lumbricoides significantly increased over the monitoring period. Through a detailed analysis of named child records, evidence of predisposition to helminth (re)infection and individual bias towards polyparasitism was detected, highlighting the often overlapping distribution of these parasites within the school-aged child. [Copyright &y& Elsevier]

Summary: Accurate diagnostic tools are pivotal for patient management and surveillance of helminth control programmes, particularly in the current era of preventive chemotherapy. Three consecutive stool samples were obtained from 279 schoolchildren from Zanzibar, an island where anthelminthic drugs have been administered on a large scale for more than a decade. All stool samples were examined with the Kato–Katz method. Additionally, one sample per child was preserved in sodium acetate–acetic acid-formalin solution, and examined with the FLOTAC technique. Considering the pooled results of both methods as diagnostic ‘gold’ standard, the observed prevalences of Trichuris trichiura, hookworm and Ascaris lumbricoides were 63.4, 35.8 and 22.9%, respectively. The sensitivity of examining a single stool sample by FLOTAC for diagnosing T. trichiura, hookworm and A. lumbricoides was 88.7, 83.0 and 82.8%, respectively. Lower sensitivities were observed for Kato–Katz even after examining three stool samples: 71.8, 46.0 and 70.3%, respectively. Kato–Katz revealed considerably higher infection intensities than FLOTAC. The κ agreement between a single FLOTAC and triplicate Kato–Katz was 0.63 for diagnosing A. lumbricoides and 0.50 for T. trichiura, but only 0.30 for hookworm. The high sensitivity of FLOTAC holds promise for patient management, monitoring soil-transmitted helminth transmission and endpoint(s) of control at the population level. [Copyright &y& Elsevier]

Summary: Contemporary control of schistosomiasis is typically reliant upon large-scale administration of praziquantel (PZQ) to school age children. Whilst PZQ treatment of each child is inexpensive, the direct and indirect costs of preventive chemotherapy for the whole school population are more substantive and, at the national level where many schools are targeted, maximising cost effectiveness and the health impact are essential requirements for ensuring longer-term sustainability (i.e. >5 years). To this end, the WHO has issued a set of treatment guidelines, inclusive of re-treatment schedules, such that, where possible, treatment decisions by school are based upon local disease prevalence as determined by parasitological and/or questionnaire methods. As each diagnostic method has known shortcomings, presumptive treatment of at-risk schools may initially be preferred, especially if the existing infrastructure for disease surveillance is poor. It is against this background of school-based preventive chemotherapy that a rapid diagnostic test (RDT) for schistosomiasis is most urgently needed, not only to improve initial disease surveillance but also to focus drug delivery better through time. In this paper, the development, evaluation and application of selected diagnostic tests are reviewed to identify barriers that impede progress, foremost of which is that a new disease surveillance and evaluation model is required where the in-country price of each RDT ideally needs to be less than US$1 to be cost effective both in the short- and long-term perspective. [Copyright &y& Elsevier]

The pulmonate snails of the genus Biomphalaria are widely distributed in the tropics, and they are intermediate hosts of the digenean trematode Schistosoma mansoni that causes intestinal schistosomiasis in humans. Recent molecular evidence suggests that Biomphalaria originated in South America, and following a recent transatlantic migration colonized Africa, where it radiated into the currently recognized 12 species. In the present study we further investigate the internal phylogenetic relationships of African Biomphalaria with emphasis on the dispersal and speciation on the continent, especially in the Great Lakes in East Africa. Our results, based on 16S ribosomal DNA, cytochrome oxidase subunit I (COI), and ribosomal internal transcribed spacer I (ITS1), support the monophyly of an African clade with two separate lineages ( Biomphalaria pfeifferi/ Biomphalaria camerunensis and the Nilotic species complex/ Biomphalaria angulosa). Following the initial colonization of Africa, Biomphalaria spread towards the east where a later radiation occurred in the Lake Victoria basin and the Albertine Rift Valley Lakes. With further dispersal along the River Nile, additional speciation took place giving origin to the North-east African species Biomphalaria alexandrina. Our results present almost no support of the species groups of Mandahl-Barth (except for the pfeifferi group), which is in accordance with other molecular appraisals. Our results suggest that Biomphalaria stanleyi, which is endemic to Lake Albert, is not an ecophenotype of the continental B. pfeifferi as previously suggested by other molecular studies. B. angulosa is sequenced for the first time and it is inferred to have an important phylogenetic position as sister group to the Albertine Rift/Lake Victoria basin radiation. © 2007 The Linnean Society of London, Zoological Journal of the Linnean Society, 2007, 151, 337–349. [ABSTRACT FROM AUTHOR]

Summary: The objectives of this study were to determine the prevalence and distribution of distended abdomens among Ugandan school children across a range of eco-epidemiological settings and to investigate the relationship between distended abdomens and helminth infections, in particular Schistosoma mansoni, before and 1-year after anthelminthic treatment. A cross-sectional survey was conducted on 4354 school children across eight districts, with a longitudinal 1-year follow-up of 2644 children (60.7%). On both occasions, parasitological, biometrical and clinical data were collected for each child. Baseline prevalence of S. mansoni and hookworms was 44.3% and 51.8%, respectively. Distended abdomens, defined as an abdominal circumference ratio (ACR) >1.05, were observed in 2.5% of the sampled children, several of whom presented with particularly severe distensions necessitating hospital referral. ACR scores were highly overdispersed between districts and schools. Multivariate regression analysis revealed that S. mansoni infection accounted for only a small fraction of ACR variation, suggesting that either single point prevalence and intensity measures failed to reflect this more chronically evolved morbidity and/or that other interacting factors were involved, e.g. malnutrition and malaria. At 1-year follow-up, ACR scores showed an overall trend of regression towards the mean, potentially indicative of amelioration following chemotherapy, but geographic overdispersion still remained. [Copyright &y& Elsevier]

Summary: Schistosomiasis caused by infection with Schistosoma mansoni is a serious public health burden in 38 of the 56 districts of Uganda. This article reviews the initial experience of the national control programme. Launched in 2003, this started with a pilot phase with the main aim of utilizing the experience to formulate feasible and appropriate methods of drug delivery. Overall, 432746 people were treated and coverage was 91.4% in schools and 64.7% in communities. The issues raised by independent evaluators included that most communities did not participate in the selection of community drug distributors (CDD) and that teachers and CDDs needed refresher training mainly on health education and the management of side effects. As a way forward, it is suggested that the Ministry of Health should integrate deworming into the existing health infrastructure so that every time a child is reached for any health service, the child is also dewormed. [Copyright &y& Elsevier]

Abstract: In large-scale interventions for control of schistosomiasis, use of the WHO dose pole is favoured for mass drug administration of praziquantel. Application of this simple tool has enabled pragmatic tablet dosing using patient height as a proxy for bodyweight, allowing control programmes to expand into resource-poor settings. Here we briefly summarize the inception and development of the existing WHO dose pole and discuss a proposed update which now permits dosing of infants and preschool children (height<94cm). Using this pole, we suggest that mass drug administration can be better optimized, streamlining general treatment to reduce drug wastage which could lead to significant programmatic savings and allocation of treatments to younger children with minimal additional cost. [ABSTRACT FROM AUTHOR]