Development of CRISPR/Cas13a-based assays for the diagnosis of Schistosomiasis.

BACKGROUND: Schistosomiasis is a disease that significantly impacts human health in the developing world. Effective diagnostics are urgently needed for improved control of this disease. CRISPR-based technology has rapidly accelerated the development of a revolutionary and powerful diagnostics platform, resulting in the advancement of a class of ultrasensitive, specific, cost-effective and portable diagnostics, typified by applications in COVID-19/cancer diagnosis. METHODS: We developed CRISPR-based diagnostic platform SHERLOCK (Specific High-sensitivity Enzymatic Reporter unLOCKing) for the detection of Schistosoma japonicum and S. mansoni by combining recombinase polymerase amplification (RPA) with CRISPR-Cas13a detection, measured via fluorescent or colorimetric readouts. We evaluated SHERLOCK assays by using 150 faecal/serum samples collected from Schistosoma-infected ARC Swiss mice (female), and 189 human faecal/serum samples obtained from a S. japonicum-endemic area in the Philippines and a S. mansoni-endemic area in Uganda. FINDINGS: The S. japonicum SHERLOCK assay achieved 93-100% concordance with gold-standard qPCR detection across all the samples. The S. mansoni SHERLOCK assay demonstrated higher sensitivity than qPCR and was able to detect infection in mouse serum as early as 3 weeks post-infection. In human samples, S. mansoni SHERLOCK had 100% sensitivity when compared to qPCR of faecal and serum samples. INTERPRETATION: These schistosomiasis diagnostic assays demonstrate the potential of SHERLOCK/CRISPR-based diagnostics to provide highly accurate and field-friendly point-of-care tests that could provide the next generation of diagnostic and surveillance tools for parasitic neglected tropical diseases. FUNDING: Australian Infectious Diseases Research Centre seed grant (2022) and National Health and Medical Research Council (NHMRC) of Australia (APP1194462, APP2008433).

Identification of a linear B-cell epitope on the Schistosoma japonicum saposin protein, SjSAP4: Potential as a component of a multi-epitope diagnostic assay.

BACKGROUND: Schistosoma japonicum is one of three major species of blood flukes causing schistosomiasis, a disease, which continues to be a major public health issue in the Philippines. SjSAP4, a member of a multigene family of saposin-like proteins, is a recognized immunodiagnostic biomarker for schistosomiasis japonica. This study aimed to identify linear B-cell epitopes on SjSAP4 and to validate their potential as components of a multi-epitope assay for the serological diagnosis of schistosomiasis japonica. METHODOLOGY: SjSAP4-derived peptides were expressed as GST-peptide-fused proteins and these were Western blot probed with human serum samples from S. japonicum Kato-Katz (KK)-positive individuals and uninfected controls. A core epitope was further identified by Western blotting through probing a series of truncated peptides with the schistosomiasis patient sera. The diagnostic performance of the core epitope-containing peptides and the full-length SjSAP4 was evaluated by enzyme-linked immunosorbent assay (ELISA) using a panel of sera collected from subjects resident in a schistosomiasis-endemic area of the Philippines. MAIN FINDINGS: As a result of the peptide mapping, one peptide (P15) was found to be highly immunogenic in the KK-positive individuals. We subsequently showed that -S163QCSLVGDIFVDKYLD178- is a core B-cell epitope of P15. Subsequent ELISAs incorporating SjSAP4, SjSAP4-Peptide and SjSP-13V2-Peptide showed a sensitivity of 94.0%, 46.0% and 74.0%, respectively, and a specificity of 97.1%, 100% and 100%, respectively. Notably, complementary recognition of the B-cell epitopes (SjSAP4-Peptide and SjSP-13V2-Peptide) was observed in a subset of the KK-positive individuals. A dual epitope-ELISA (SjSAP4-Peptide + SjSP-13V2-Peptide-ELISA) showed a diagnostic sensitivity of 84.0% and a specificity of 100%. CONCLUSIONS/SIGNIFICANCE: In this study, -S163QCSLVGDIFVDKYLD178- was identified as a dominant linear B-cell epitope on SjSAP4. This peptide and the complementary recognition of other B-cell epitopes using sera from different KK-positive individuals can provide the basis of developing a multi-epitope assay for the serological diagnosis of schistosomiasis.

Effect of maternal praziquantel treatment for Schistosoma japonicum infection on the offspring susceptibility and immunologic response to infection at age six, a cohort study.

In areas endemic to schistosomiasis, fetal exposure to schistosome antigens prime the offspring before potential natural infection. Praziquantel (PZQ) treatment for Schistosoma japonicum infection in pregnant women has been demonstrated to be safe and effective. Our objectives were to evaluate whether maternal PZQ treatment modifies the process of in utero sensitization to schistosome antigens potentially impacting later risk of infection, as well as immune response to S. japonicum. We enrolled 295 children at age six, born to mothers with S. japonicum infection who participated in a randomized control trial of PZQ versus placebo given at 12-16 weeks gestation in Leyte, The Philippines. At enrollment, we assessed and treated current S. japonicum infection and measured serum cytokines. During a follow-up visit four weeks later, we assessed peripheral blood mononuclear cell (PBMC) cytokine production in response to soluble worm antigen preparation (SWAP) or soluble egg antigen (SEA). Associations between maternal treatment group and the child's S. japonicum infection status and immunologic responses were determined using multivariate linear regression analysis. PZQ treatment during pregnancy did not impact the prevalence (P = 0.12) or intensity (P = 0.59) of natural S. japonicum infection among children at age six. Among children with infection at enrollment (12.5%) there were no significant serum cytokine concentration differences between maternal treatment groups. Among children with infection at enrollment, IL-1 production by PBMCs stimulated with SEA was higher (P = 0.03) in the maternal PZQ group compared to placebo. Among children without infection, PBMCs stimulated with SEA produced greater IL-12 (P = 0.03) and with SWAP produced less IL-4 (P = 0.01) in the maternal PZQ group compared to placebo. Several cytokines produced by PBMCs in response to SWAP and SEA were significantly higher in children with S. japonicum infection irrespective of maternal treatment: IL-4, IL-5, IL-10, and IL-13. We report that maternal PZQ treatment for S. japonicum shifted the PBMC immune response to a more inflammatory signature but had no impact on their offspring's likelihood of infection or serum cytokines at age six, further supporting the safe use of PZQ in pregnant women. Trial Registration: ClinicalTrials.gov NCT00486863.

Population Pharmacokinetics of Praziquantel in Pregnant and Lactating Filipino Women Infected with Schistosoma japonicum.

An estimated 40 million women of reproductive age are infected with one of three species of the waterborne parasite Schistosoma spp. Treatment with praziquantel (PZQ) via mass drug administration (MDA) campaigns is the mainstay of schistosomiasis control for populations living in areas of endemicity. The World Health Organization recommends that pregnant and lactating women be included in schistosomiasis MDA programs, and several recent studies have evaluated the safety and efficacy of PZQ use during pregnancy. To date, there are no data describing PZQ pharmacokinetics (PK) during pregnancy or among lactating postpartum women. As part of a randomized controlled trial investigating the safety and efficacy of PZQ during human pregnancy, we examined the PK of this therapeutic drug among three distinct cohorts of women infected with S. japonicum in Leyte, Philippines. Specifically, we studied the PK properties of PZQ among early- and late-gestation pregnant women (n = 15 each) and lactating postpartum women (n = 15) with schistosomiasis. We found that women in early pregnancy had increased apparent clearance and lower area-under-the-curve (AUC0-24) values that may be related to physiological changes in drug clearance and/or changes in oral bioavailability. There was no relationship between body weight and apparent clearance. The mean ± standard deviation partition ratio of plasma to breast milk was 0.36. ± 0.13. The estimated median infant PZQ daily dose would be 0.037 mg/kg of body weight ingested from breast milk, which is significantly lower than the dosage required for antischistosomal activity and not known to be harmful to the infant. Our PK data do not support the suggestion to delay breastfeeding 72 h after taking PZQ. Results can help inform future drug efficacy studies in pregnant and lactating women with schistosomiasis.

Helminths, polyparasitism, and the gut microbiome in the Philippines.

Polyparasitism, involving soil-transmitted helminths. and Schistosoma blood flukes, is common in low to middle income countries. These helminths impact on the gut environment and can cause changes to the gut microbiome composition. Here we examined the gut microbiome in individuals with polyparasitism from two human cohorts in the Philippines utilising DNA sequencing-based profiling. Multiple helminth species infections were high with 70.3% of study participants harbouring at least two parasite species, and 16% harbouring at least five species. Increased numbers of helminth co-infections, in particular with the gut-resident soil-transmitted helminths, were significantly associated with increased bacterial diversity; however no significant parasite-gut microbiome associations were evident for individuals infected only with Schistosoma japonicum. In general, a healthy gut is associated with high bacterial diversity, which in these human cohorts may be the result of helminth-mediated immune modulation, or due to changes in the gut environment caused by these parasitic helminths.

Maternal, placental and cord blood cytokines and the risk of adverse birth outcomes among pregnant women infected with Schistosoma japonicum in the Philippines.

BACKGROUND: The objectives of this study were to 1) evaluate the influence of treatment with praziquantel on the inflammatory milieu in maternal, placental, and cord blood, 2) assess the extent to which proinflammatory signatures in placental and cord blood impacts birth outcomes, and 3) evaluate the impact of other helminths on the inflammatory micro environment. METHODS/FINDINGS: This was a secondary analysis of samples from 369 mother-infant pairs participating in a randomized controlled trial of praziquantel given at 12-16 weeks' gestation. We performed regression analysis to address our study objectives. In maternal peripheral blood, the concentrations of CXCL8, and TNF receptor I and II decreased from 12 to 32 weeks' gestation, while IL-13 increased. Praziquantel treatment did not significantly alter the trajectory of the concentration of any of the cytokines examined. Hookworm infection was associated with elevated placental IL-1, CXCL8 and IFN-γ. The risk of small-for-gestational age increased with elevated IL-6, IL-10, and CXCL8 in cord blood. The risk of prematurity was increased when cord blood sTNFRI and placental IL-5 were elevated. CONCLUSIONS: Our study suggests that fetal cytokines, which may be related to infectious disease exposures, contribute to poor intrauterine growth. Additionally, hookworm infection influences cytokine concentrations at the maternal-fetal interface. CLINICAL TRIAL REGISTRY NUMBER AND WEBSITE: ClinicalTrials.gov (NCT00486863).

Maternal anemia type during pregnancy is associated with anemia risk among offspring during infancy.

BACKGROUND: We evaluated the association between etiology of maternal anemia and iron status throughout infancy. METHODS: Samples from a study designed to examine Praziquantel treatment during pregnancy were used (n = 359). All women were infected with schistosomiasis and randomized to Praziquantel or placebo at 16 ± 2 weeks' gestation. Hemoglobin, serum ferritin (SF), soluble transferrin receptor (sTfR), hepcidin, C-reactive protein, and interleukin-6 were measured in maternal and infant blood. The relationship between both maternal Praziquantel treatment and etiology of anemia and infant iron status was evaluated. RESULTS: Maternal iron-deficiency anemia was associated with increased risk of infant anemia at 6 months of age. Infants of mothers with the lowest levels of circulating hepcidin during gestation, likely a marker for iron deficiency, had higher sTfR:SF levels and lower hemoglobin levels, particularly at 12 months of age. Maternal non-iron-deficiency anemia (NIDA) did not impact infant anemia risk or iron status. Maternal treatment for schistosomiasis had no effect on infant hematologic status. CONCLUSIONS: Maternal iron deficiency anemia was associated with an increased risk for anemia or iron deficiency during late infancy. We did not observe an association between maternal NIDA and increased risk for iron deficiency during infancy.

Co-parasitism of intestinal protozoa and Schistosoma japonicum in a rural community in the Philippines.

BACKGROUND: Co-parasitism is a frequent occurrence in impoverished communities in the tropics resulting in a considerable disease burden. While there are extensive reports of intestinal helminthiases, including schistosomiasis japonica, the occurrence and extent of diseases caused by intestinal protozoa (IP) have yet to be investigated in depth in the Philippines. We present a detailed analysis of polyparasitism in a rural community of Northern Samar, focusing on co-infections of IP with Schistosoma japonicum. METHODS: A descriptive cross sectional study was carried out in 2015 across 18 barangays (villages) endemic for S. japonicum in Northern Samar, the Philippines to assess the burden of human schistosomiasis and IP infections. Faecal samples collected from 412 participants from the 18 barangays were included in the final molecular analysis. A multiplex quantitative PCR assay was developed and used for the detection of Blastocystis spp., Entamoeba histolytica, Cryptosporidium spp. and Giardia duodenalis in stool samples. The findings were combined with previous results of droplet digital PCR diagnosis of individuals from the same 18 barangays infected with S. japonicum determined using the same stool samples for analysis. RESULTS: Mean age of the study participants was 40.3 years (95% CI: 38.8-41.8) with 53% (n = 218) being males. Prevalence of S. japonicum (74.5%) and Blastocystis spp. (58.7%) was significantly higher compared to other infections, with E. histolytica having the lowest prevalence (12.1%). A majority of individuals were infected with more than one parasite with two infections being most common (n = 175, 42.5%). The prevalence of individuals with two parasites was significantly higher than all others with 27.9% (n = 115) subjects harbouring a single parasite species. Of individuals with two infections, S. japonicum and Blastocystis spp. were the most common combination (n = 110, 62.9%). Examining age within the population, 58.5% (n = 38) of school-aged children and 60.1% (n = 14) of women of child bearing age harboured at least two parasite species. CONCLUSIONS: The study revealed that polyparasitism with IP infections and schistosomiasis japonica is highly prevalent in individuals in Northern Samar which likely contributes to the significant public health and socio-economic burden suffered by this population. More generally, the findings are of relevance when considering implementation of integrated control strategies for intestinal parasites.

Anemia of Inflammation during Human Pregnancy Does Not Affect Newborn Iron Endowment.

Background: To our knowledge, no studies have addressed whether maternal anemia of inflammation (AI) affects newborn iron status, and few have addressed risk factors for specific etiologies of maternal anemia. Objectives: The study aims were to evaluate 1) the contribution of AI and iron deficiency anemia (IDA) to newborn iron endowment, 2) hepcidin as a biomarker to distinguish AI from IDA among pregnant women, and 3) risk factors for specific etiologies of maternal anemia. Methods: We measured hematologic biomarkers in maternal blood at 12 and 32 wk of gestation and in cord blood from a randomized trial of praziquantel in 358 pregnant women with Schistosoma japonicum in The Philippines. IDA was defined as anemia with serum ferritin <30 ng/mL and non-IDA (NIDA), largely due to AI, as anemia with ferritin ≥30 ng/mL. We identified cutoffs for biomarkers to distinguish IDA from NIDA by using area under the curve (AUC) analyses and examined the impact of different causes of anemia on newborn iron status (primary outcome) by using multivariate regression modeling. Results: Of the 358 mothers, 38% (n = 136) had IDA and 9% (n = 32) had NIDA at 32 wk of gestation. At 32 wk of gestation, serum hepcidin performed better than soluble transferrin receptor (sTfR) in identifying women with NIDA compared with the rest of the cohort (AUCs: 0.75 and 0.70, respectively) and in identifying women with NIDA among women with anemia (0.73 and 0.72, respectively). The cutoff that optimally distinguished women with NIDA from women with IDA in our cohort was 6.1 µg/L. Maternal IDA, but not NIDA, was associated with significantly lower newborn ferritin (114.4 ng/mL compared with 148.4 µg/L; P = 0.042). Conclusions: Hepcidin performed better than sTfR in identifying pregnant women with NIDA, but its cost may limit its use. Maternal IDA, but not NIDA, is associated with decreased newborn iron stores, emphasizing the need to identify this cause and provide iron therapy. This trial was registered at www.clinicaltrials.gov as NCT00486863.

Praziquantel for the treatment of schistosomiasis during human pregnancy.

In 2014, an estimated 40 million women of reproductive age were infected with Schistosoma haematobium, S. japonicum and/or S. mansoni. In both 2003 and 2006, the World Health Organization (WHO) recommended that all schistosome-infected pregnant and breastfeeding women be offered treatment, with praziquantel, either individually or during treatment campaigns. In 2006, WHO also stated the need for randomized controlled trials to assess the safety and efficacy of such treatment. Some countries have yet to follow the recommendation on treatment and many programme managers and pregnant women in other countries remain reluctant to follow the recommended approach. Since 2006, two randomized controlled trials on the use of praziquantel during pregnancy have been conducted: one against S. mansoni in Uganda and the other against S. japonicum in the Philippines. In these trials, praziquantel treatment of pregnant women had no significant effect on birth weight, appeared safe and caused minimal side-effects that were similar to those seen in treated non-pregnant subjects. Having summarized the encouraging data, on efficacy, pharmacokinetics and safety, from these two trials and reviewed the safety data from non-interventional human studies, we recommend that all countries include pregnant women in praziquantel treatment campaigns. We identify the barriers to the treatment of pregnant women, in countries that already include such women in individual treatments and mass drug administration campaigns, and discuss ways to address these barriers.

En 2014, on estimait que 40 millions de femmes en âge de procréer étaient infectées par Schistosoma haematobium, S. japonicum et/ou S. mansoni. En 2003 et 2006, l'Organisation mondiale de la Santé (OMS) a recommandé qu'un traitement au praziquantel soit offert, individuellement ou dans le cadre de campagnes de traitement, à toutes les femmes enceintes et allaitantes infectées par le schistosome. En 2006, l'OMS a également affirmé la nécessité d'essais contrôlés randomisés pour évaluer l'innocuité et l'efficacité de ce traitement. Néanmoins, certains pays ne suivent toujours pas la recommandation relative au traitement et dans d'autres pays, bon nombre de gestionnaires de programme et de femmes enceintes demeurent réticents à suivre l'approche recommandée. Depuis 2006, deux essais contrôlés randomisés sur l'utilisation du praziquantel au cours de la grossesse ont été menés: l'un sur S. mansoni en Ouganda et l'autre sur S. japonicum aux Philippines. Dans le cadre de ces essais, le traitement au praziquantel des femmes enceintes n'a pas eu d'effet notable sur le poids à la naissance, s'est révélé sans danger et a provoqué des effets secondaires minimes, similaires à ceux constatés chez les femmes traitées qui n'étaient pas enceintes. Ayant résumé les données encourageantes sur l'efficacité, la pharmacocinétique et l'innocuité tirées de ces deux essais et examiné les données de sécurité provenant d'études non interventionnelles sur l'homme, nous recommandons que tous les pays incluent les femmes enceintes dans des campagnes de traitement au praziquantel. Nous mettons en évidence les obstacles qui empêchent le traitement des femmes enceintes ­ dans des pays les incluant déjà dans des traitements individuels et des campagnes d'administration massive de médicaments ­ et décrivons des moyens permettant de surmonter ces obstacles.

En 2014, se estima que 40 millones de mujeres en edad reproductiva estaban infectadas con Schistosoma haematobium, S. japonicum y/o S. mansoni. Tanto en 2003 como en 2006, la Organización Mundial de la Salud (OMS) recomendó que todas las mujeres embarazadas y lactantes infectadas con esquistosoma recibieran tratamiento, con praziquantel, ya fuera individualmente o durante las campañas de tratamiento. En 2006, la OMS también informó de la necesidad de ensayos aleatorizados controlados para evaluar la seguridad y la eficacia de dicho tratamiento. Algunos países todavía tienen que seguir la recomendación sobre el tratamiento y muchos gestores de programas y mujeres embarazadas en otros países siguen siendo reacios a seguir el enfoque recomendado. Desde 2006, se han llevado a cabo dos ensayos aleatorizados controlados sobre el uso de praziquantel durante el embarazo: uno contra el S. mansoni en Uganda y el otro contra el S. japonicum en Filipinas. En estos ensayos, el tratamiento con praziquantel en mujeres embarazadas no tuvo un efecto significativo sobre el peso en el momento del nacimiento, pareció seguro y causó efectos secundarios mínimos, similares a los observados en sujetos no embarazadas tratadas. Después de resumir los alentadores datos sobre la eficacia, la farmacocinética y la seguridad de estos dos ensayos y revisar los datos de seguridad de los estudios observacionales en humanos, recomendamos que todos los países incluyan a mujeres embarazadas en las campañas de tratamiento con praziquantel. Identificamos las barreras para el tratamiento de mujeres embarazadas, en países que ya incluyen a mujeres en los tratamientos individuales y en las campañas masivas de administración de medicamentos, y analizamos las formas de abordar estas barreras.

A new global strategy for the elimination of schistosomiasis.

Mass drug administration utilising a single oral dose of 40mg/kg of praziquantel (PZQ) has been endorsed and advocated by the World Health Organisation (WHO) for the global control and elimination of schistosomiasis. However, this strategy is failing primarily because the drugs are not getting to the people who need them the most. The current global coverage is 20%, the drug compliance rate is less than 50%, and the drug efficacy is approximately 50%. Thus in reality, only about 5% of the reservoir human population is actually receiving intermittent chemotherapy. Despite claims that more of the drug will soon be made available the current strategy is inherently flawed and will not lead to disease elimination. We discuss the many practical issues related to this global strategy, and advocate for an integrated control strategy targeting the life cycle and the most at-risk. Moreover, we discuss how an integrated control package for schistosomiasis should fit within a larger integrated health package for rural and remote villages in the developing world. A holistic health system approach is required to achieve sustainable control and ultimately disease elimination.

Biennial versus annual treatment for schistosomiasis and its impact on liver morbidity.

OBJECTIVE: This study assessed the impact of annual versus biennial praziquantel treatment regimens on the prevalence, intensity of infection, and liver fibrosis dynamics of Asiatic schistosomiasis (caused by Schistosoma japonicum) among individuals residing in 18 endemic barangays in Northern Samar, Philippines. METHODS: Five hundred and sixty-five subjects who reported symptoms of gastrointestinal illness and/or were believed to have clinical morbidity based on physical examination were selected for cohort follow-up. RESULTS: The mean prevalence of schistosomiasis was 34% and the mean intensity of infection was 123.1 eggs per gram. Moderate to severe hepatic fibrosis (grade II/III) was demonstrated in approximately 25% of the study population. As expected, a greater reduction in both the prevalence and intensity of infection was documented with two treatment rounds versus one. Overall, hepatic fibrosis (grades I-III) regressed in only 24.3% of those who received a single treatment and in only 19.3% of those who received two doses. The prevalence of grade II-III fibrosis at baseline (25.2%) remained unchanged 2 years after treatment. CONCLUSIONS: These findings suggest that in order to reverse moderate to severe liver fibrosis due to schistosomiasis and improve clinical outcomes, a higher clinical dosage of praziquantel (i.e., 60-80mg/kg) may be required over an extended duration.

Diagnosing schistosomiasis-induced liver morbidity: implications for global control.

BACKGROUND: Subclinical morbidity due to schistosomiasis was evaluated in 565 patients, and the enhanced liver fibrosis (ELF) test was assessed for the first time as a potential screening tool for disease. METHODS: The prevalence and intensity of infection were determined by Kato-Katz thick smear stool examination at baseline and 2 years after curative treatment. The degree of hepatic fibrosis was assessed by ultrasound. Non-invasive serum biomarkers of hepatic fibrosis were also evaluated. RESULTS: The baseline human prevalence and infection intensity were found to be moderately high at 34% and 123 eggs per gram, respectively. However, hepatic parenchymal fibrosis occurred in 50% of subjects, with grade II fibrosis in 19% and grade III in 6%. The ELF score and higher serum levels of tissue inhibitor of metalloproteinase 1 (TIMP-1) and hyaluronic acid (HA) correlated with the grade of liver fibrosis. CONCLUSIONS: The findings of this study demonstrated that praziquantel treatment had a short-term impact on both the prevalence and intensity of infection, but less of an impact on established morbidity. Higher TIMP-1 and HA serum levels, and an ELF cut-off score of 8 were found to be correlated with the grade of liver fibrosis; these values may, therefore, assist physicians in identifying individuals at greater risk of disease.

Efficacy and safety of praziquantel for the treatment of human schistosomiasis during pregnancy: a phase 2, randomised, double-blind, placebo-controlled trial.

BACKGROUND: Despite WHO recommendations to offer pregnant women treatment with praziquantel, many nations continue to withhold treatment, awaiting data from controlled trials addressing safety and efficacy. The objectives of this study were to assess whether treatment of pregnant women with schistosomiasis at 12-16 weeks gestation leads to improved maternal and newborn outcomes and to collect maternal and newborn safety data. METHODS: This phase 2, randomised, double-blind, placebo-controlled trial was done in 72 baranguays (villages) serviced by six municipal health centres in a schistosomiasis endemic region of northeastern Leyte, Philippines. Pregnant women (at 12-16 weeks gestation) who were otherwise healthy but infected with Schistosoma japonicum were enrolled and randomly assigned (1:1) to receive either over-encapsulated praziquantel (total dose 60 mg/kg given as two split doses) or placebo. Participants, investigators, midwives, and laboratory staff were all masked to treatment. The primary outcome was birthweight. Safety data were collected including immediate reactogenicity, post-dosing toxicology ascertained 24 h after study drug administration, and maternal and newborn serious adverse events. Analysis followed the intention-to-treat principle. Analyses were done using hierarchical generalised linear models to adjust for identified confounders and account for potential clustering of observations within villages and municipalities. This trial is registered with ClinicalTrials.gov, number NCT00486863. FINDINGS: Between Aug 13, 2007, and Dec 3, 2012, 370 pregnant women were enrolled and randomly assigned to each treatment group (184 to the placebo group, 186 to the praziquantel group). Most women had low-intensity infections (n=334, 90%). Treatment with praziquantel did not have a significant effect on birthweight (2·85 kg in both groups, ß=-0·002 [95% CI -0·088 to 0·083]; p=0·962). Treatment was well tolerated with reactogenicity rates similar to those seen in non-pregnant participants (severe reactions occurred in five patients in the praziquantel group and two in the placebo group, and included headache, fever, and malaise). There were no significant differences in key safety outcomes including abortion, fetal death in utero, and congenital anomalies. INTERPRETATION: Results from this study provide important data from a controlled trial in support of the expansion of treatment policies to include pregnant women as recommended by WHO. FUNDING: National Institutes of Health, National Institute of Allergy and Infectious Diseases (U01AI066050).

Access to essential paediatric surgery in the developing world: a case of imperforate anus with rectovaginal and rectocutaneous fistulas left untreated.

Anorectal malformations consist of a wide spectrum of conditions which can affect both sexes and involve the distal anus and rectum as well as the urinary and genital tracts. Patients have the best chance of a good functional outcome if the condition is diagnosed early and efficient anatomic repair is promptly instituted. This report describes a rare case of imperforate anus associated with both rectovaginal and rectocutaneous fistulas in a 6-year-old Filipino girl. The case highlights shortcomings in the healthcare delivery system combined with socio-economic factors that contributed to the delay in both diagnosis and the institution of adequate treatment. Care and preventive measures that can be implemented in low-resource settings to reduce the impact of birth defects are also discussed.

Access to essential paediatric eye surgery in the developing world: a case of congenital cataracts left untreated.

Childhood cataracts are a major cause of treatable blindness. Early recognition, surgical intervention and appropriate follow-up after surgery can result in good visual outcomes. However, several factors may impact on the availability of such services, including lack of an available, affordable and accessible comprehensive eye care centre, financial limitations affecting coverage by the national healthcare provider, and household socioeconomic status. We report a case of congenital cataracts in a 12-year-old male adolescent from Northern Samar, the Philippines, who was left blind since birth. This case highlights the disparities in essential health services in the developing world and the challenges patients face in getting the care they need.

Multiplex real-time PCR monitoring of intestinal helminths in humans reveals widespread polyparasitism in Northern Samar, the Philippines.

The global socioeconomic importance of helminth parasitic disease is underpinned by the considerable clinical impact on millions of people. While helminth polyparasitism is considered common in the Philippines, little has been done to survey its extent in endemic communities. High morphological similarity of eggs between related species complicates conventional microscopic diagnostic methods which are known to lack sensitivity, particularly in low intensity infections. Multiplex quantitative PCR diagnostic methods can provide rapid, simultaneous identification of multiple helminth species from a single stool sample. We describe a multiplex assay for the differentiation of Ascaris lumbricoides, Necator americanus, Ancylostoma, Taenia saginata and Taenia solium, building on our previously published findings for Schistosoma japonicum. Of 545 human faecal samples examined, 46.6% were positive for at least three different parasite species. High prevalences of S. japonicum (90.64%), A. lumbricoides (58.17%), T. saginata (42.57%) and A. duodenale (48.07%) were recorded. Neither T. solium nor N. americanus were found to be present. The utility of molecular diagnostic methods for monitoring helminth parasite prevalence provides new information on the extent of polyparasitism in the Philippines municipality of Palapag. These methods and findings have potential global implications for the monitoring of neglected tropical diseases and control measures.

Can mass drug administration lead to the sustainable control of schistosomiasis?

BACKGROUND: In the Philippines, the current national control strategy for schistosomiasis is annual mass drug administration (MDA) with 40 mg/kg of praziquantel in all schistosomiasis-endemic villages with a prevalence ≥10%. METHODS: A cross-sectional survey of schistosomiasis was conducted in 2012 on 18 221 individuals residing in 22 schistosomiasis-endemic villages in the province of Northern Samar. The prevalence of schistosomiasis, intensity of Schistosoma infection, and morbidity of disease were assessed. RESULTS: Despite an active schistosomiasis-control program in Northern Samar for >30 years, which included a MDA campaign in the last 5 years, the mean prevalence of schistosomiasis among 10 435 evaluated subjects was 27.1% (95% confidence interval [CI], 26.3%-28.0%), and the geometric mean intensity of infection among 2832 evaluated subjects was 17.2 eggs per gram of feces (95% CI, 16.4-18.1). Ultrasonography revealed high levels of schistosomiasis-induced morbidity in the schistosomiasis-endemic communities. Left lobe liver enlargement (≥70 mm) was evident in 89.3% of subjects. Twenty-five percent of the study population had grade II/III liver parenchyma fibrosis, and 13.3% had splenomegaly (≥100 mm). CONCLUSIONS: MDA on its own was insufficient to control the prevalence of schistosomiasis, intensity of Schistosoma infection, or morbidity of the disease. Alternative control measures will be needed to complement the existing national MDA program.

The chronic enteropathogenic disease schistosomiasis.

Schistosomiasis is a chronic enteropathogenic disease caused by blood flukes of the genus Schistosoma. The disease afflicts approximately 240 million individuals globally, causing approximately 70 million disability-adjusted life years lost. Chronic infections with morbidity and mortality occur as a result of granuloma formation in the intestine, liver, or in the case of Schistosoma haematobium, the bladder. Various methods are utilized to diagnose and evaluate liver fibrosis due to schistosomiasis. Liver biopsy is still considered the gold standard, but it is invasive. Diagnostic imaging has proven to be an invaluable method in assessing hepatic morbidity in the hospital setting, but has practical limitations in the field. The potential of non-invasive biological markers, serum antibodies, cytokines, and circulating host microRNAs to diagnose hepatic fibrosis is presently undergoing evaluation. This review provides an update on the recent advances made with respect to gastrointestinal disease associated with chronic schistosomiasis.