Multiplex PCR for bacterial, viral and protozoal pathogens in persistent diarrhoea or persistent abdominal pain in Côte d'Ivoire, Mali and Nepal.

In contrast to acute diarrhoea, the aetiology of persistent digestive disorders (≥ 14 days) is poorly understood in low-resource settings and conventional diagnostic approaches lack accuracy. In this multi-country study, we compared multiplex real-time PCR for enteric bacterial, parasitic and viral pathogens in stool samples from symptomatic patients and matched asymptomatic controls in Côte d'Ivoire, Mali and Nepal. Among 1826 stool samples, the prevalence of most pathogens was highest in Mali, being up to threefold higher than in Côte d'Ivoire and up to tenfold higher than in Nepal. In all settings, the most prevalent bacteria were EAEC (13.0-39.9%) and Campylobacter spp. (3.9-35.3%). Giardia intestinalis was the predominant intestinal protozoon (2.9-20.5%), and adenovirus 40/41 was the most frequently observed viral pathogen (6.3-25.1%). Significantly different prevalences between symptomatic and asymptomatic individuals were observed for Campylobacter, EIEC and ETEC in the two African sites, and for norovirus in Nepal. Multiple species pathogen infection was common in Côte d'Ivoire and Mali, but rarely found in Nepal. We observed that molecular testing detected multiple enteric pathogens and showed low discriminatory accuracy to distinguish between symptomatic and asymptomatic individuals. Yet, multiplex PCR allowed for direct comparison between different countries and revealed considerable setting-specificity.

Antimalarial artesunate-mefloquine versus praziquantel in African children with schistosomiasis: an open-label, randomized controlled trial.

Schistosomiasis treatment entirely relies on a single drug, praziquantel, prompting research into alternative therapeutics. Here we evaluated the efficacy and safety of the antimalarial combination artesunate-mefloquine for the treatment of schistosomiasis in a proof-of-concept, pragmatic, open-label, randomized controlled trial in primary schools of six villages endemic for schistosomiasis in northern Senegal. Children (6-14 years) were eligible if Schistosoma eggs were detected by microscopy in urine and/or stool. In total, 726 children were randomized 1:1 to praziquantel (standard care: 40 mg kg-1 single dose; n = 364) or to artesunate-mefloquine (antimalarial dosage: artesunate 4 mg kg-1 and mefloquine 8 mg kg-1 daily for three consecutive days; n = 362). Eight children not meeting the inclusion criteria were excluded from efficacy analysis. Median age of the remaining 718 participants was 9 years; 399 (55.6%) were male, and 319 (44.4%) female; 99.3% were infected with Schistosoma haematobium and 15.2% with S. mansoni. Primary outcomes were cure rate, assessed by microscopy, and frequency of drug-related adverse effects of artesunate-mefloquine versus praziquantel at 4 weeks after treatment. Cure rate was 59.6% (208/349) in the artesunate-mefloquine arm versus 62.1% (211/340) in the praziquantel arm. The difference of -2.5% (95% confidence interval (CI) -9.8 to 4.8) met the predefined criteria of noninferiority (margin set at 10%). All drug-related adverse events were mild or moderate, and reported in 28/361 children receiving artesunate-mefloquine (7.8%; 95% CI 5.4 to 11.0) versus 8/363 (2.2%; 95% CI 1.1 to 4.3) receiving praziquantel (P < 0.001). Artesunate-mefloquine at antimalarial dosage was moderately safe and noninferior to standard-care praziquantel for the treatment of schistosomiasis, predominantly due to S. haematobium. Multicentric trials in different populations and epidemiological settings are needed to confirm these findings. ClinicalTrials.gov identifier: NCT03893097 .

Association of both Water, Sanitation and Hygiene (WASH) and Infant and Young Child Feeding (IYCF) practices with childhood malnutrition in Lao PDR: a cross-sectional study of the 2017 Lao Social Indicator Survey II.

OBJECTIVE: We assessed whether Water, Sanitation and Hygiene (WASH) and Infant and Young Child Feeding (IYCF), either alone or combined, were associated with malnutrition among Lao People's Democratic Republic (Lao PDR) children aged 6 to <24 months. DESIGN: This is a secondary analysis of the 2017 Lao Social Indicator Survey II (LSIS II), which used multistage probability proportional to size sampling. Logistic regression analyses were conducted with OR and its corresponding 95% CI. SETTING: The LSIS II was conducted a nationwide household-based survey covering all 18 provinces in Lao PDR. PARTICIPANTS: We had a total of 3375 children (weighted sample 3345) and 357 households with data on drinking water. OUTCOME MEASURES: The outcomes of this study were stunting and wasting. RESULTS: The prevalence of stunting and wasting was 28.9% and 10.1%, respectively. Even though households with access to a basic or improved water source were high (82.5%), over 83% of drinking water was contaminated with Escherichia coli. Access to improved sanitation, basic hygiene and adequate IYCF gave a significant lower risk of becoming stunted. The combined effect of these practices on stunting was (adjusted OR (AOR)=0.54; 95% CI=0.41 to 0.73) greater than each practice alone (improved sanitation: AOR=0.75; 95% CI=0.61 to 0.93; basic hygiene: AOR=0.69; 95% CI=0.57 to 0.83; adequate IYCF: AOR=0.79; 95% CI=0.64 to 0.98). Access to improved sanitation and adequate IYCF was associated with a significant lower risk for being wasted, and again the combined effect of these practices was (AOR=0.64; 95% CI=0.44 to 0.92) greater than each practice alone (improved sanitation: AOR=0.68; 95% CI=0.49 to 0.93 and adequate IYCF: AOR=0.66; 95% CI=0.47 to 0.92). CONCLUSION: Given the strong associations with both stunting and wasting, and the added benefits when combining WASH and IYCF, there is a need of multisectoral interventions to reduce early childhood malnutrition in Lao PDR.

Can direct smear results that are routinely collected at health centre level be used for monitoring the impact of mass drug administration with praziquantel on schistosomiasis in Burundi? A preliminary assessment.

BACKGROUND: Intestinal schistosomiasis is still a public health problem in Burundi. Since 2008, annual mass drug administration with praziquantel has been rolled out in 11 endemic districts. The national programme relies on school-based surveys with kato-katz to monitor the impact of mass drug administration. We explored whether routine data on intestinal schistosomiasis as determined by direct fecal smears at health centre level could be used. METHODS: From the Burundian National Health Information System, we collected routine incidence data on intestinal schistosomiasis as determined by direct smear examination in all 45 sanitary districts during 2011-2015. A temporal trends analysis was performed using a mixed negative binomial regression. Sanitary districts with mass drug administration campaigns with praziquantel (n = 11) were compared with those without (n = 34). In addition, prevalence data on intestinal schistosomiasis based on kato-katz results from a school-based national mapping in 2014 were compared with the incidence data in health centres based on direct smear results, in the same 45 sanitary districts. RESULTS: In the 11 sanitary districts applying mass drug administration with praziquantel, the incidence rate decreased significantly for the years 2014 (ß2014 = - 0.826, P = 0.010) and 2015 (ß2015 = - 1.294, P < 0.001) and for the five-year period (ß = - 0.286, P < 0.001), whereas in the 34 districts where mass drug administration was not delivered, there was no significant decrease over time (ß = - 0.087, P = 0.219). In most of the 45 sanitary districts, the low prevalence based on kato-katz in school children was confirmed by low incidence rates based on direct smears in the health centres. CONCLUSIONS: National Health Information System surveillance data, based on routinely collected direct smear results at health centre level, may be able to monitor the impact of mass drug administration with praziquantel on intestinal schistosomiasis in Burundi. Control and elimination of intestinal schistosomiasis call for integration of adequate diagnosis and treatment into routine activities of primary health care facilities, as recommended by the World Health Organization since more than 20 years. When moving towards elimination, more sensitive tests, such as the point-of-care circulating cathodic antigen assay are desirable.

Capacity gaps in health facilities for case management of intestinal schistosomiasis and soil-transmitted helminthiasis in Burundi.

BACKGROUND: Schistosomiasis and soil-transmitted helminthiasis (STH) are endemic diseases in Burundi. STH control is integrated into health facilities (HF) across the country, but schistosomiasis control is not. The present study aimed to assess the capacity of HF for integrating intestinal schistosomiasis case management into their routine activities. In addition, the current capacity for HF-based STH case management was evaluated. METHODS: A random cluster survey was carried out in July 2014, in 65 HF located in Schistosoma mansoni and STH endemic areas. Data were collected by semi-quantitative questionnaires. Staff with different functions at the HF were interviewed (managers, care providers, heads of laboratory and pharmacy and data clerks). Data pertaining to knowledge of intestinal schistosomiasis and STH symptoms, human and material resources and availability and costs of diagnostic tests and treatment were collected. FINDINGS: Less than half of the 65 care providers mentioned one or more major symptoms of intestinal schistosomiasis (abdominal pain 43.1%, bloody diarrhoea 13.9% and bloody stool 7.7%). Few staff members (15.7%) received higher education, and less than 10% were trained in-job on intestinal schistosomiasis case management. Clinical guidelines and laboratory protocols for intestinal schistosomiasis diagnosis and treatment were available in one third of the HF. Diagnosis was performed by direct smear only. Praziquantel was not available in any of the HF. The results for STH were similar, except that major symptoms were more known and cited (abdominal pain 69.2% and diarrhoea 60%). Clinical guidelines were available in 61.5% of HF, and albendazole or mebendazole was available in all HF. CONCLUSIONS: The current capacity of HF for intestinal schistosomiasis and STH detection and management is inadequate. Treatment was not available for schistosomiasis. These issues need to be addressed to create an enabling environment for successful integration of intestinal schistosomiasis and STH case management into HF routine activities in Burundi for better control of these diseases.

Epidemiology of polyparasitism with Taenia solium, schistosomes and soil-transmitted helminths in the co-endemic village of Malanga, Democratic Republic of Congo.

Helminth co-infections are common in sub-Saharan Africa. However, little is known about the distribution and determinants of co-infections with Taenia solium taeniasis/cysticercosis. Building on a previous community-based study on human cysticercosis in Malanga village, we investigated co-infections with Taenia solium, soil-transmitted helminths (STHs) and Schistosoma spp and associated risk factors in a random subsample of 330 participants. Real time PCR assays were used to detect DNA of soil-transmitted helminths (STHs), T. solium and Schistosoma in stool samples and Schistosoma DNA in urine samples. Serum samples were tested for T. solium cysticercosis using the B158/B60 monoclonal antibody-based antigen ELISA. Bivariate analysis and logistic regression were applied to assess associations of single and co-infections with common risk factors (age, sex, area, hygiene) as well as pair wise associations between helminth species. Overall, 240 (72.7%) participants were infected with at least one helminth species; 128 (38.8%) harbored at least two helminth species (16.1% with STHs-Schistosoma, 14.5% with STHs-T. solium taeniasis/cysticercosis and 8.2% with Schistosoma-T. solium taeniasis/cysticercosis co-infections). No significant associations were found between Schistosoma-T. solium taeniasis/cysticercosis co-infection and any of the risk factors studied. Males (OR=2 (95%CI=1.1-5), p=0.03) and open defecation behavior (OR=3.8 (95%CI=1.1-6.5), p=0.04) were associated with higher odds of STHs-T. solium taeniasis/cysticercosis co-infection. Village districts that were found at high risk of T. solium taeniasis/cysticercosis were also at high risk of co-infection with STHs and T. solium taeniasis/cysticercosis (OR=3.2 (95%CI=1.1-7.8), p=0.03). Significant pair-wise associations were found between T. solium cysticerci and Necator americanus (OR=2.2 (95%CI=1.2-3.8), p<0.01) as well as Strongyloides stercoralis (OR=2.7 (95%CI=1.1-6.5), p=0.02). These findings show that co-infections with T. solium are common in this polyparasitic community in DRC. Our results on risk factors of helminth co-infections and specific associations between helminths may contribute to a better integration of control within programmes that target more than one NTD.

Diagnosing Polyparasitism in a High-Prevalence Setting in Beira, Mozambique: Detection of Intestinal Parasites in Fecal Samples by Microscopy and Real-Time PCR.

BACKGROUND: Many different intestinal parasite species can co-occur in the same population. However, classic diagnostic tools can only frame a particular group of intestinal parasite species. Hence, one or two tests do not suffice to provide a complete picture of infecting parasite species in a given population. The present study investigated intestinal parasitic infections in Beira, Mozambique, i.e. in the informal settlement of Inhamudima. Diagnostic accuracy of five classical microscopy techniques and real-time PCR for the detection of a broad spectrum of parasites was compared. METHODOLOGY/PRINCIPAL FINDINGS: A cross-sectional population-based survey was performed. One stool sample per participant (n = 303) was examined by direct smear, formal-ether concentration (FEC), Kato smear, Baermann method, coproculture and real-time PCR. We found that virtually all people (96%) harbored at least one helminth, and that almost half (49%) harbored three helminths or more. Remarkably, Strongyloides stercoralis infections were widespread with a prevalence of 48%, and Ancylostoma spp. prevalence was higher than that of Necator americanus (25% versus 15%), the hookworm species that is often assumed to prevail in East-Africa. Among the microscopic techniques, FEC was able to detect the broadest spectrum of parasite species. However, FEC also missed a considerable number of infections, notably S. stercoralis, Schistosoma mansoni and G. intestinalis. PCR outperformed microscopy in terms of sensitivity and range of parasite species detected. CONCLUSIONS/SIGNIFICANCE: We showed intestinal parasites-especially helminths-to be omnipresent in Inhamudima, Beira. However, it is a challenge to achieve high diagnostic sensitivity for all species. Classical techniques such as FEC are useful for the detection of some intestinal helminth species, but they lack sensitivity for other parasite species. PCR can detect intestinal parasites more accurately but is generally not feasible in resource-poor settings, at least not in peripheral labs. Hence, there is a need for a more field-friendly, sensitive approach for on-the-spot diagnosis of parasitic infections.

Geospatial and age-related patterns of Taenia solium taeniasis in the rural health zone of Kimpese, Democratic Republic of Congo.

BACKGROUND: Taenia solium infections are mostly endemic in less developed countries where poor hygiene conditions and free-range pig management favor their transmission. Knowledge on patterns of infections in both human and pig is crucial to design effective control strategies. The aim of this study was to assess the prevalence, risk factors and spatial distribution of taeniasis in a rural area of the Democratic Republic of Congo (DRC), in the prospect of upcoming control activities. METHODS: A cross-sectional study was conducted in 24 villages of the health zone of Kimpese, Bas Congo Province. Individual and household characteristics, including geographical coordinates were recorded. Stool samples were collected from willing participants and analyzed using the copro-antigen enzyme-linked immunosorbent assay (copro-Ag ELISA) for the detection of taeniasis. Blood samples were collected from pigs and analyzed using the B158/B60 monoclonal antibody-based antigen ELISA (sero-Ag ELISA) to detect porcine cysticercosis. Logistic regression and multilevel analysis were applied to identify risk factors. Global clustering and spatial correlation of taeniasis and porcine cysticercosis were assessed using K functions. Local clusters of both infections were identified using the Kulldorff's scan statistic. RESULTS: A total of 4751 participants above 5 years of age (median: 23 years; IQR: 11-41) were included. The overall proportion of taeniasis positivity was 23.4% (95% CI: 22.2-24.6), ranging from 1 to 60% between villages, with a significant between-household variance of 2.43 (SE=0.29, p<0.05). Taeniasis was significantly associated with age (p<0.05) and the highest positivity was found in the 5-10 years age group (27.0% (95% CI: 24.4-29.7)). Overall, 45.6% (95% CI: 40.2-51) of sampled pigs were sero-positive. The K functions revealed a significant overall clustering of human and pig infections but no spatial dependence between them. Two significant clusters of taeniasis (p<0.001; n=276 and n=9) and one cluster of porcine cysticercosis (p<0.001; n=24) were found. CONCLUSION: This study confirms high endemicity and geographical dispersal of taeniasis in the study area. The role of age in taeniasis patterns and significant spatial clusters of both taeniasis and porcine cysticercosis were evidenced, though no spatial correlation was found between human and pig infections. Urgent control activities are needed for this endemic area.

Toxocariasis diagnosed in international travelers at the Institute of Tropical Medicine, Antwerp, Belgium, from 2000 to 2013.

Although infection with Toxocara canis or T. catis (commonly referred as toxocariasis) appears to be highly prevalent in (sub)tropical countries, information on its frequency and presentation in returning travelers and migrants is scarce. In this study, we reviewed all cases of asymptomatic and symptomatic toxocariasis diagnosed during post-travel consultations at the reference travel clinic of the Institute of Tropical Medicine, Antwerp, Belgium. Toxocariasis was considered as highly probable if serum Toxocara-antibodies were detected in combination with symptoms of visceral larva migrans if present, elevated eosinophil count in blood or other relevant fluid and reasonable exclusion of alternative diagnosis, or definitive in case of documented seroconversion. From 2000 to 2013, 190 travelers showed Toxocara-antibodies, of a total of 3436 for whom the test was requested (5.5%). Toxocariasis was diagnosed in 28 cases (23 symptomatic and 5 asymptomatic) including 21 highly probable and 7 definitive. All but one patients were adults. Africa and Asia were the place of acquisition for 10 and 9 cases, respectively. Twelve patients (43%) were short-term travelers (< 1 month). Symptoms, when present, developed during travel or within 8 weeks maximum after return, and included abdominal complaints (11/23 symptomatic patients, 48%), respiratory symptoms and skin abnormalities (10 each, 43%) and fever (9, 39%), often in combination. Two patients were diagnosed with transverse myelitis. At presentation, the median blood eosinophil count was 1720/µL [range: 510-14160] in the 21 symptomatic cases without neurological complication and 2080/µL [range: 1100-2970] in the 5 asymptomatic individuals. All patients recovered either spontaneously or with an anti-helminthic treatment (mostly a 5-day course of albendazole), except both neurological cases who kept sequelae despite repeated treatments and prolonged corticotherapy. Toxocariasis has to be considered in travelers returning from a (sub)tropical stay with varying clinical manifestations or eosinophilia. Prognosis appears favorable with adequate treatment except in case of neurological involvement.

Use of expressed sequence tags as an alternative approach for the identification of Taenia solium metacestode excretion/secretion proteins.

BACKGROUND: Taenia solium taeniasis/cysticercosis is a zoonotic helminth infection mainly found in rural regions of Africa, Asia and Latin America. In endemic areas, diagnosis of cysticercosis largely depends on serology, but these methods have their drawbacks and require improvement. This implies better knowledge of the proteins secreted and excreted by the parasite. In a previous study, we used a custom protein database containing protein sequences from related helminths to identify T. solium metacestode excretion/secretion proteins. An alternative or complementary approach would be to use expressed sequence tags combined with BLAST and protein mapping to supercontigs of Echinococcus granulosus, a closely related cestode. In this study, we evaluate this approach and compare the results to those obtained in the previous study. FINDINGS: We report 297 proteins organized in 106 protein groups based on homology. Additional classification was done using Gene Ontology information on biological process and molecular function. Of the 106 protein groups, 58 groups were newly identified, while 48 groups confirmed previous findings. Blast2GO analysis revealed that the majority of the proteins were involved in catalytic activities and binding. CONCLUSIONS: In this study, we used translated expressed sequence tags combined with BLAST and mapping strategies to both confirm and complement previous research. Our findings are comparable to recent studies on other helminth genera like Echinococcus, Schistosoma and Clonorchis, indicating similarities between helminth excretion/secretion proteomes.

Parasitosis intestinales en pacientes con epilepsia de origen desconocido / Intestinal parasitosis found in patients with epilepsy of unknown etiology

Introducción: la epilepsia es una alteración del sistema nervioso central que afecta a un estimado de 50 millones de personas en el mundo, de los cuales 85 porciento vive en países en desarrollo. Alrededor de 20 porciento de las epilepsias son de difícil control o refractarias. En Cuba no existen antecedentes de estudios acerca del comportamiento de las parasitosis intestinales en estos pacientes, por lo cual se decidió realizar la presente investigación en un grupo de pacientes con epilepsia de origen desconocido del Instituto de Neurología y Neurocirugía de La Habana. Objetivos: determinar la prevalencia y las manifestaciones clínicas de las parasitosis intestinales, y relacionar estas infecciones con la existencia de epilepsia refractaria a los fármacos antiepilépticos. Métodos: se aplicó un cuestionario y se recogió una muestra de heces por cada paciente, se realizaron técnicas de diagnóstico coproparasitológico, como son el examen directo, el método de concentración de Willis y el procedimiento cuantitativo de Kato Katz

Introduction: the epilepsy is an alteration of the central nervous system (CNS) which roughly affects 50 millions of persons worldwide; almost 85 percent of them live in developing countries. Approximately 20 percent of epilepsies are difficult to control or they are called refractory epilepsies. Taking into account the lack of Cuban reports about the behavior of intestinal parasitic infections in these patients, it was decided to carry out this research study in a group of epileptic patients with unknown etiology, from the Institute of Neurology and Neurosurgery in Havana. Objectives: to determine the prevalence and the clinical manifestations of intestinal parasitic infections, and the possible association of these infections with epilepsy refractory to the antiepileptic drugs. Methods: a questionnaire was applied and one fecal sample was taken per patient. Various parasitological techniques were implemented, including direct wet mount, Willis concentration technique, and Kato Katz quantitative procedure

Rapid diagnostic tests for neurological infections in central Africa.

Infections are a leading cause of life-threatening neuropathology worldwide. In central African countries affected by endemic diseases such as human African trypanosomiasis, tuberculosis, HIV/AIDS, and schistosomiasis, delayed diagnosis and treatment often lead to avoidable death or severe sequelae. Confirmatory microbiological and parasitological tests are essential because clinical features of most neurological infections are not specific, brain imaging is seldom feasible, and treatment regimens are often prolonged or toxic. Recognition of this diagnostic bottleneck has yielded major investment in application of advances in biotechnology to clinical microbiology in the past decade. We review the neurological pathogens for which rapid diagnostic tests are most urgently needed in central Africa, detail the state of development of putative rapid diagnostic tests for each, and describe key technical and operational challenges to their development and implementation. Promising field-suitable rapid diagnostic tests exist for the diagnosis of human African trypanosomiasis and cryptococcal meningoencephalitis. For other infections-eg, syphilis and schistosomiasis-highly accurate field-validated rapid diagnostic tests are available, but their role in diagnosis of disease with neurological involvement is still unclear. For others-eg, tuberculosis-advances in research have not yet yielded validated tests for diagnosis of neurological disease.

T-helper 17 cells are associated with pathology in human schistosomiasis.

BACKGROUND: Schistosome infections are often clinically silent, but some individuals develop severe pathological reactions. In several disease processes, T-helper 17 (Th17) cells have been linked to tissue injuries, while regulatory T cells (Tregs) are thought to downmodulate inflammatory reactions. We assessed whether bladder pathology in human Schistosoma haematobium infection is related to the balance of Th17 cells and Tregs. We used a murine model of Schistosoma mansoni infection to further investigate whether the peripheral profiles reflected ongoing events in tissues. METHODS: We characterized T-helper cell subsets in the peripheral blood of children residing in a S. haematobium-endemic area and in the peripheral blood, spleen, and hepatic granulomas of S. mansoni-infected high-pathology CBA mice and low-pathology C57BL/6 mice. RESULTS: S. haematobium-infected children with bladder pathology had a significantly higher percentage of Th17 cells than those without pathology. Moreover, the Th17/Treg ratios were significantly higher in infected children with pathology, compared with infected children without pathology. Percentages of interleukin 17-producing cells were significantly higher in spleen and granulomas of CBA mice, compared with C57BL/6 mice. This difference was also reflected in the peripheral blood. CONCLUSIONS: This is the first study to indicate that Th17 cells may be involved in the pathogenesis of human schistosomiasis.

Proteomic analysis of Taenia solium metacestode excretion-secretion proteins.

The metacestode larval stage of Taenia solium is the causal agent of a zoonotic disease called cysticercosis. The disease has an important impact on pork trade (due to porcine cysticercosis) and public health (due to human neurocysticercosis). In order to improve the current diagnostic tools and to get a better understanding of the interaction between T. solium metacestodes and their host, there is a need for more information about the proteins that are released by the parasite. In this study, we used protein sequences from different helminths, 1DE, reversed-phase LC, and MS/MS to analyze the excretion-secretion proteins produced by T. solium metacestodes from infected pigs. This is the first report of the T. solium metacestode excretion-secretion proteome. We report 76 proteins including 27 already described T. solium proteins, 17 host proteins and 32 proteins likely to be of T. solium origin, but identified using sequences from other helminths.

High prevalence of Taenia solium cysticerosis in a village community of Bas-Congo, Democratic Republic of Congo.

Cysticercosis results from tissue infection with the larval stage of the pig tapeworm Taenia solium. Infection of the brain may cause neurocysticercosis, the most frequent cause of acquired epilepsy in developing countries. Information on human cysticercosis in the Democratic Republic of Congo (DRC) is scarce and outdated. We believe this is the first reported study on human cysticercosis and epilepsy in a village community of DRC. The proportion of villagers seropositive by ELISA for T. solium circulating antigen was 21.6%, the highest figure reported to date. The adjusted prevalence of active epilepsy in the community was 12.7 in 1,000.

Interactions between Global Health Initiatives and country health systems: the case of a neglected tropical diseases control program in Mali.

BACKGROUND: Recently, a number of Global Health Initiatives (GHI) have been created to address single disease issues in low-income countries, such as poliomyelitis, trachoma, neonatal tetanus, etc.. Empirical evidence on the effects of such GHIs on local health systems remains scarce. This paper explores positive and negative effects of the Integrated Neglected Tropical Disease (NTD) Control Initiative, consisting in mass preventive chemotherapy for five targeted NTDs, on Mali's health system where it was first implemented in 2007. METHODS AND FINDINGS: Campaign processes and interactions with the health system were assessed through participant observation in two rural districts (8 health centres each). Information was complemented by interviews with key informants, website search and literature review. Preliminary results were validated during feedback sessions with Malian authorities from national, regional and district levels. We present positive and negative effects of the NTD campaign on the health system using the WHO framework of analysis based on six interrelated elements: health service delivery, health workforce, health information system, drug procurement system, financing and governance. At point of delivery, campaign-related workload severely interfered with routine care delivery which was cut down or totally interrupted during the campaign, as nurses were absent from their health centre for campaign-related activities. Only 2 of the 16 health centres, characterized by a qualified, stable and motivated workforce, were able to keep routine services running and to use the campaign as an opportunity for quality improvement. Increased workload was compensated by allowances, which significantly improved staff income, but also contributed to divert attention away from core routine activities. While the campaign increased the availability of NTD drugs at country level, parallel systems for drug supply and evaluation requested extra efforts burdening local health systems. The campaign budget barely financed institutional strengthening. Finally, though the initiative rested at least partially on national structures, pressures to absorb donated drugs and reach short-term coverage results contributed to distract energies away from other priorities, including overall health systems strengthening. CONCLUSIONS: Our study indicates that positive synergies between disease specific interventions and nontargeted health services are more likely to occur in robust health services and systems. Disease-specific interventions implemented as parallel activities in fragile health services may further weaken their responsiveness to community needs, especially when several GHIs operate simultaneously. Health system strengthening will not result from the sum of selective global interventions but requires a comprehensive approach.

Taenia solium cysticercosis in the Democratic Republic of Congo: how does pork trade affect the transmission of the parasite?

BACKGROUND: Taenia solium, a zoonotic parasite that is endemic in most developing countries where pork is consumed, is recognised as the main cause of acquired epilepsy in these regions. T. solium has been reported in almost all of the neighboring countries of Democratic Republic of Congo (DRC) but data on the current prevalence of the disease in the country itself are lacking. This study, focusing on porcine cysticercosis (CC), makes part of a first initiative to assess whether cysticercosis is indeed actually present in DRC. METHODS: An epidemiological study on porcine CC was conducted (1) on urban markets of Kinshasa where pork is sold and (2) in villages in Bas-Congo province where pigs are traditionally reared. Tongue inspection and ELISA for the detection of circulating antigen of the larval stage of T. solium were used to assess the prevalence of active CC in both study sites. FINDINGS: The overall prevalence of pigs with active cysticercosis did not significantly differ between the market and the village study sites (38.8 [CI 95%: 34-43] versus 41.2% [CI 95%: 33-49], respectively). However, tongue cysticercosis was only found in the village study site together with a significantly higher intensity of infection (detected by ELISA). INTERPRETATION: Pigs reared at village level are sold for consumption on Kinshasa markets, but it seems that highly infected animals are excluded at a certain level in the pig trade chain. Indeed, preliminary informal surveys on common practices conducted in parallel revealed that pig farmers and/or buyers select the low infected animals and exclude those who are positive by tongue inspection at village level. This study provides the only recent evidence of CC presence in DRC and gives the first estimates to fill an important gap on the African taeniasis/cysticercosis distribution map.

Associations between specific antibody responses and resistance to reinfection in a Senegalese population recently exposed to Schistosoma mansoni.

We examined associations between schistosome-specific antibody responses and reinfection in Senegalese individuals recently exposed to Schistosoma mansoni. The effects of treatment, age, intensity of infection and duration of exposure on schistosome-specific antibody responses were also investigated by comparing immune responses in individuals exposed for less than 3 years with responses in people exposed for more than 8 years. All individuals were bled before treatment as well as 6 and 12 weeks after. We used a statistical model that included interaction terms between time, age, infection intensity and duration of exposure. The overall patterns of most specific antibody responses by age were similar to those previously published for S. mansoni, Schistosoma japonicum and Schistosoma haematobium infections in different endemic areas. In general, a boost in specific antibody responses against adult worm antigen (SWA) was observed at 6 weeks after treatment whereas the majority of isotype responses against egg antigen (SEA) were not affected by treatment. Our analysis showed that the effect of treatment on schistosome-specific antibody responses is influenced by age, infection intensity and duration of exposure. We found no evidence that treatment matures the specific antibody response of children recently infected with S. mansoni. Our results indicate that the build-up of potentially protective immunoglobulin E (IgE) responses was associated with duration of exposure, or, in other words, experience of infection. Interestingly, in recently exposed individuals there was a significant association between IgA responses to SWA and resistance to reinfection. Resistance to reinfection and production of IgA-SWA was associated with adulthood independently of exposure patterns, suggesting that susceptibility to S. mansoni and the development of protective immune responses is age-dependent.

Human schistosomiasis.

Schistosomiasis or bilharzia is a tropical disease caused by worms of the genus Schistosoma. The transmission cycle requires contamination of surface water by excreta, specific freshwater snails as intermediate hosts, and human water contact. The main disease-causing species are S haematobium, S mansoni, and S japonicum. According to WHO, 200 million people are infected worldwide, leading to the loss of 1.53 million disability-adjusted life years, although these figures need revision. Schistosomiasis is characterised by focal epidemiology and overdispersed population distribution, with higher infection rates in children than in adults. Complex immune mechanisms lead to the slow acquisition of immune resistance, though innate factors also play a part. Acute schistosomiasis, a feverish syndrome, is mostly seen in travellers after primary infection. Chronic schistosomal disease affects mainly individuals with long-standing infections in poor rural areas. Immunopathological reactions against schistosome eggs trapped in the tissues lead to inflammatory and obstructive disease in the urinary system (S haematobium) or intestinal disease, hepatosplenic inflammation, and liver fibrosis (S mansoni, S japonicum). The diagnostic standard is microscopic demonstration of eggs in the excreta. Praziquantel is the drug treatment of choice. Vaccines are not yet available. Great advances have been made in the control of the disease through population-based chemotherapy but these required political commitment and strong health systems.