Husnawati, Eka; Lusiyana, Novyan
Schistosomiasis, also known as bilharzia, is a zoonosis disease caused by blood flukes (trematodes) of the genus Schistosoma sp. There are a few species that can infect humans and animals, including Schistosoma aponicum, Schistosoma mansonia, Schistosoma hematobium, Schistosoma intercalatum Schistosoma guineensis and Schistosoma mekongi.1 This disease is endemic in 78 countries, in which 52 of them are countries with moderate-high level of endemicity. Schistosoma sp are very difficult to elim...
Full Text Available In hospital-based series viral hepatitis B has been frequently described in association with schistosomiasis whilst in field-based studies the association has not been confirmed. The association between schistosomiasis and Salmonella bacteraemia has been well documented. More recently, acute schistosomiasis has been shown to be a facilitating factor in the genesis of pyogenic liver abscesses caused by Staphylococcus aureus. New evidences indicate an interaction between the acquired immunodeficiency syndrome (AIDS and schistosomiasis. In this paper, data on the association of schistosomiasis with other infections are updated.
0b013e3182704d1e]. 5. Sanelli PC, Lev MH, Gonzalez RG, Schaefer PW. Unique linear and nodular MR enhancement pattern in schistosomiasis of the central nervous system: Report of three patients. AJR 2001;177(6):1471-1474. Cerebral schistosomiasis.
Utzinger, Jürg; Brattig, Norbert W.; Kristensen, Thomas K.
, social and cross-cutting issues pertaining to the epidemiology and control of schistosomiasis. We summarize key achievements made by CONTRAST, many of which are featured in this special issue of Acta Tropica. Together with an independent view put forth by an eminent schistosomiasis researcher...... alliance to optimize schistosomiasis control and transmission surveillance in sub-Saharan Africa - was ahead of the game. Indeed, launched in October 2006, this 4-year project funded by the European Commission made important contributions for sustainable schistosomiasis control in the selected African...... countries through innovation, validation and application of new tools and locally adapted intervention strategies complementary to preventive chemotherapy. Moreover, CONTRAST articulated a research agenda for schistosomiasis elimination, framed by 10 key questions. Here, we provide a rationale for CONTRAST...
Makaula, Peter; Sadalaki, John R.; Muula, Adamson S.
and Google Scholar using th keywords: "schistosomiasis", "Bilharzia", "Bulinus" and "Biomphalaria" in combination with "Malawi". These searche were supplemented by iterative reviews of reference lists for relevant publications in peer reviewed internationa scientific journals or other media. The recovered......Introduction: Schistosomiasis remains an important public health problem that undermines social and economi development in tropical regions of the world, mainly Sub-Saharan Africa. We are not aware of any systematic revie of the literature of the epidemiology and transmission of schistosomiasis...... in Malawi since 1985. Therefore, w reviewed the current state of knowledge of schistosomiasis epidemiology and transmission in this country an identified knowledge gaps and relevant areas for future research and research governance Methods: We conducted computer-Aided literature searches of Medline, SCOPUS...
McCullough, F. S.; Gayral, Ph.; DUNCAN, J; Christie, J. D.
Although mollusciciding can be a cost-effective method of controlling schistosomiasis transmission, only one organic molluscicide, niclosamide, is now being produced commercially, and only a few compounds are at present being tested in the laboratory. In future, improved cost-effective use of molluscicides will require more precise knowledge of schistosomiasis transmission patterns in each endemic area and improved application techniques. In snail control studies using controlled-release form...
Full Text Available In 1975 the Special Programme for Schistosomiasis Control was introduced in Brazil with the objective of controlling this parasitic disease in six northeastern states. The methodology applied varied largely from state to state, but was based mainly on chemotherapy, This Programme was modified about ten years after it beginning with the main goals including control of morbidity and the blockage of establishment of new foci in non-endemic areas. In two states, Bahia and Minas Gerais, the schistosomiasis control programme started in 1979 and 1983, respectively. The recently made evaluation of those two programmes is the main focus of this paper. It must also be pointed out, that the great majority of the studies performed by different researchers in Brazil, at different endemic areas, consistently found significant decrease on prevalence and incidence, when control measures are repeatedly used for several years. Significant decrease of hepatosplenic forms in the studied areas is well documented in Brazil. After more than 20 years of schistosomiasis control programmes in our country, chemotherapy has shown to be a very important tool for the control of morbidity and to decrease prevalence and incidence in endemic areas. Nevertheless, in medium and long terms, sanitation, water supply, sewage draining and health education seem to be the real tools when the aim is persistent and definitive schistosomiasis control.
Luiz C. de S. Dias
Full Text Available Despite the success of control programmes, schistosomiasis is still a serious public health problem in the world. More than 70 countries where 200 million individuals are evaluated to be infected of a total 600 million at risk. Though there have been important local success in the control of transmission, globally the infection has increased. Economic constrains in developing countries, environmental changes associated with migration and water resources development have been blocking the progress. The main objective of schistosomiasis control is to achieve reduction of disease due to schistosomiasis. We discussed the control measures like: health education, diagnosis and chemotherapy, safe water supplies, sanitation and snail control. We emphasized the need to give priority to school-age children and the importance of integrating the measures of control into locally available systems of health care. The control of schistosomiasis is directly related to the capacity of the preventive health services of an endemic country. The strategy of control requires long-term commitment from the international to the local level.
of adult and 26% school children could relate hematuria to wading, a common means of exposure to urinary schistosomiasis. More than half ... energy malnutrition, and reduced mental and physiological performance . Control measures ..... performance in Guatemala. Transactions of the Royal Society of Tropical Medicine ...
Full Text Available After three decades' efforts, schistosomiasis japonica were controlled in one-third (4/12 of endemic provinces and 68.2 (259/380 of endemic counties throughout the country. The remaining 121 endemic counties are located primarily in the lake and mountainous regions. The epidemiological and ecological features of the lake and mountainous areas are different from the other endemic areas. The major schistosomiasis control efforts in China can be characterized as follows: (1 Application of centralized leadership and management, since schistosomiasis control is a task not only of the Ministry of Public Health, but also of all local governments in the endemic areas; (2 Integration of actions taken by various departments or bureaus, such as agriculture, water conservation and public health; (3 Promotion of mass participation; (4 Organization of strong professional teams; (5 Raising sufficient funds. Strategies on schistosomiasis control applied in different areas are divided into three levels: (1 In the areas where the schistosomiasis has been successfully controlled, surveillance must be maintained and immediate action should be taken where new infections occur and/or vector snails are found, so that control can be reestablished quickly; (2 In the areas where schistosomiasis has been partially controlled, any residents and/or live-stock infected should be examined and treated promptly with due care, and environment modifying and/or mollusciding must be used to eliminate the remaining snails; (3 In the areas where transmission has not been controlled, the main strategy is to control morbidity. Mass or selective chemotherapy with praziquental should be applied to both infected persosns and the live-stock, and environment modification for the snail-ridden areas should be taken but should be coordinated with agriculture where possible. Advance cases must be treated; and epidemics of Katayama fever prevented; water supply and sanitation shoud be improved
Eridan M. Coutinho
Full Text Available In northeast Brazil, nutritional deficiency diseases and schistosomiasis mansoni overlap. An experimental model, wich reproduces the marasmatic clinical form of protein-energy malnutrition, was developed in this laboratory to study these interactions. Albino Swiss mice were fed with a food association ingested usually by human populations in northeast Brazil. This diet (Regional Basic Diet - RBD has negative effects on the growth, food intake and protein utilization in infected mice (acute phase of murine schistosomiasis. Nitrogen balance studies have also shown that infection with Schistosoma mansoni has apparently no effect on protein intestinal absorption in well nourished mice. However, the lowest absorption ratios have been detected among RBD - fed infected animals, suggesting that suprerimposed schistosome infection aggravated the nutritional status of the undernourished host. The serum proteins electrophoretic pattern, as far as albumins are concerned, is quite similar for non-infected undernourished and infected well-fed animals. So, the significance of albumins as a biochemical indicator of the nutritional status of human populations residing in endemic foci of Manson's schistosomiasis, is discussable.
McCullough, F S; Gayral, P; Duncan, J; Christie, J D
Although mollusciciding can be a cost-effective method of controlling schistosomiasis transmission, only one organic molluscicide, niclosamide, is now being produced commercially, and only a few compounds are at present being tested in the laboratory. In future, improved cost-effective use of molluscicides will require more precise knowledge of schistosomiasis transmission patterns in each endemic area and improved application techniques. In snail control studies using controlled-release formulations only the organotins, especially tributyltin oxide (TBTO), have given satisfactory long-term results. However, large-scale field trials of organotin formulations have not been implemented and their use cannot be recommended as their chronic toxicity in mammals has not yet been determined. The development of molluscicides of indigenous plant origin deserves support. Endod, derived from the berries of the climbing plant Phytolacca dodecandra, is the most extensively tested plant molluscicide, but data on its chronic toxicity to non-target organisms are lacking. The mode of action of molluscicides has not been extensively studied, though knowledge of the properties required of molluscicidal molecules has contributed to the discovery and development of niclosamide and nicotinanilide. In general, molluscicides probably cause stress on the water balance system, which in gastropods in thought to be under neurosecretory control.
Although schistosomiasis (bilharzia) is one of the most common parasitic infections in humans, schistosomal infection of the nervous system is rare. This report is of an unusual case of primary cerebral schistosomiasis and describes its magnetic resonance imaging appearance.
Prevalence of urinary schistosomiasis among secondary school students in Ibadan, Nigeria. ... The inclusion of health education package aimed at changing behavior of school children from adverse water contact practices was recommended. Keywords: prevalence, urinary schistosomiasis, secondary school students.
Schistosomiasis was found to be associated with hematuria (97.3%) and proteinuria (79.6%). Conclusion: Haematuria and proteinuria have a potential value in the screening for community diagnosis of urinary schistosomiasis in endemic areas. Vesical schistosomiasis is recognized as a significant public health problem ...
van Hellemond, Jaap J.; Vonk, Alieke G.; de Vogel, Corné; Koelewijn, Rob; Vaessen, Norbert; Fahal, Ahmed H.; van Belkum, Alex; van de Sande, Wendy W. J.
Eumycetoma is a morbid chronic granulomatous subcutaneous fungal disease. Despite high environmental exposure to this fungus in certain regions of the world, only few develop eumycetoma for yet unknown reasons. Animal studies suggest that co-infections skewing the immune system to a Th2-type response enhance eumycetoma susceptibility. Since chronic schistosomiasis results in a strong Th2-type response and since endemic areas for eumycetoma and schistosomiasis do regionally overlap, we performed a serological case-control study to identify an association between eumycetoma and schistosomiasis. Compared to endemic controls, eumycetoma patients were significantly more often sero-positive for schistosomiasis (p = 0.03; odds ratio 3.2, 95% CI 1.18–8.46), but not for toxoplasmosis, an infection inducing a Th1-type response (p = 0.6; odds ratio 1.5, 95% CI 0.58–3.83). Here, we show that schistosomiasis is correlated to susceptibility for a fungal disease for the first time. PMID:23717704
Full Text Available In this review the authors analyze the effector and regulatory mechanisms in the immune response to schistosomiasis. To study these mechanisms two animal models were used, mouse and rat. The mouse totaly permissive host like human, show prominent-T cell control in the acquisition of resistance. But other mechanisms like antibody mediated cytotoxity (ADCC involving eosinophils and IgG antibodies described in humans, are observed in rats. Also in this animal, it is observed specific IgE antibody high production and blood and tisssue eosinophilia. Using the rat model and schistosomula as target, some ADCC features have emerged: the cellular population involved are bone marrow derived inflammatory cell (mononuclear phagocytes, eosinophils and platelets, interacting with IgE through IgE Fc receptors. Immunization has been attempted using the recombinant protein Sm28/GST. Protection has been observed in rodents with significant decrease of parasite fecundity and egg viability affecting the number, size and volume of liver egg granulomas. The association of praziquantel and immunization with with Sm28/GST increases the resistance to infection and decreases egg viability. The authors suggest the possibility of the stablishment of a future vaccine against Schistosoma mansoni.
Fan, Kawai; Lai, Honkei
In 1956, Mao Zedong began a mass campaign against schistosomiasis in the People's Republic of China. The campaign, which integrated mass mobilization, science, agricultural production, local construction projects, and prophylactic measures, was fueled primarily by a determination to accelerate China's agricultural development. The initial success of this campaign encouraged Mao to embark on the next stage of socialism, the Great Leap Forward. As attention was diverted away from schistosomiasis, however, the disease has again become a major burden to the health of the country.
Jensen, T; Rønne-Rasmussen, J O; Bygbjerg, Ib Christian
Acute schistosomiasis (Katayama fever) may present with a broad spectrum of symptoms three to six weeks after primary infection by Schistosoma (S) mansoni, S. japonicum or, more rarely, S. haematobium. The acute phase of schistosomiasis is frequently confused with other feverish diseases. It occurs...... almost exclusively in nonimmune visitors to endemic areas. We describe seven cases of acute S. mansoni infection. The pathogenesis, clinical features, diagnosis and treatment are briefly discussed. Katayama fever should be considered in patients returning from endemic areas with fever and eosinophilia...
and colon carcinoma reviewed. SAfrMedJ1994; 84: 211-215. It has been estimated that over 250 million ... Historical background. Theodor Bilharz first found adult worms of the trema- tode, now known ..... A raised incidence of colorectal cancer in association with schistosomiasis due to S. mansoni has not been detected in ...
the lesions on the left that may be lichen planus like, but not typical. The nodules. A case of vulval schistosomiasis. O'Mahony D, MBBCh, DCH, DTM&H, DPH, DIP MID COG (SA), FRCGP. Family Practitioner, Bridge Street, Port St Johns. Banach L, MD, PhD, MIAC. Associate Professor, Department of Pathology, Faculty of ...
Andersen, L; Magnussen, Pascal; Wouters, J S
To reassess the schistosomiasis problem in Ngamiland and especially in Maun area 552 primary school children and 213 adult labourers were examined with urinalysis and rectal snip. Of the pupils 80.3% were found positive for S. mansoni and 1.4% for S. haematobium; of the labourers 35.7% were...
Emery Aidan M
Full Text Available Abstract Background The Natural History Museum (NHM is developing a repository for schistosomiasis-related material, the Schistosomiasis Collection at NHM (SCAN as part of its existing Wolfson Wellcome Biomedical Laboratory (WWBL. This is timely because a major research and evaluation effort to understand control and move towards elimination of schistosomiasis in Africa has been initiated by the Schistosomiasis Consortium for Operational Research and Evaluation (SCORE, resulting in the collection of many important biological samples, including larval schistosomes and snails. SCAN will collaborate with a number of research groups and control teams and the repository will acquire samples relevant to both immediate and future research interest. The samples collected through ongoing research and field activities, WWBL’s existing collections, and other acquisitions will be maintained over the long term and made available to the global research community for approved research purposes. Goals include: · Consolidation of the existing NHM schistosome and snail collections and transfer of specimens into suitable long-term storage systems for DNA retrieval, · Long-term and stable storage of specimens collected as part of on going field programmes initially in Africa especially relating to the SCORE research programmes, · Provision of access to snail and schistosome collections for approved research activities.
Saconato, H; Atallah, A
Schistosomiasis is a parasite that is carried by freshwater snails. The intestinal form infects the intestine, liver and spleen and can be fatal. The objective of this review was to assess the effects of oxamniquine or praziquantel for treating Schistosomiasis mansoni We searched the Cochrane Infectious Diseases Group trials register, the Cochrane Controlled Trials Register, Medline, Lilacs and reference lists of articles. The Revista da Sociedade Brasileira de Medicina Tropical and Brazilian Tropical Medicine Congress abstracts were handsearched Randomised and quasi-randomised trials comparing oxamniquine and/or praziquantel to placebo for the treatment of Schistosomiasis mansoni. Two reviewers independently assessed trial quality and extracted data. Thirteen trials met the inclusion criteria. Praziquantel and oxamniquine were effective in curing Schistosoma mansoni infection when compared to placebo. In Africa, praziquantel 40 mg/Kg is more effective than oxamniquine 15 mg/Kg in individuals older than 14 years (OR 3.54, 95%CI 1.70, 7.38), but no difference was found when compared with oxamniquine 30 mg/Kg (OR 0.29, 95%CI 0.08, 1.01). In Brazil, praziquantel was equally effective when compared with oxamniquine in individuals older than 14 years (OR 1.70, 95%CI 0.83, 3.49). Both drugs appear safe. There was no difference in reinfection rate between zinc supplementation and placebo (OR 0.82, 95%CI 0.47, 1.41). IPraziquantel and oxamniquine both appear to be effective for the treatment of Schistosomiasis mansoni, although lower doses of oxamniquine (less than 30 milligrams per kilogram) may not be as effective.
Oct 10, 2006 ... Revista Do Institution De Medicina Tropical de Sao Paulo. 1962; 8: 167-172. 5. Jones H.J.S., Ibrahim A.E.K. and Deroda J.K.. Schistosomiasis of the appendix in the UK. Brit. J. Clin. Pract. 1997; 51: 183. 6. Lee J.FY., Chung C.C. and Lau W.Y. A case of schistosomal appendicitis. IJCP 1997; 51: 518-519. 7.
It is generally accepted that schistosomiasis, if not causative, is at least associated with malignancy. In this review, the epidemiology of schistosomiasis and bladder carcinoma, as well as the role of chronic bladder infection, are discussed together with known carcinogenic factors, possible abnormal vitamin metabolism ...
Most respondents were familiar with the snails' habitats, but had poor knowledge on aquatic plants harbouring snails, as 57% of the respondents did not know about aquatic plants being associated with schistosomiasis snails. Only 3% of the respondents associated snails with schistosomiasis transmission. Sixty percent ...
Africa, affecting populations living where water supply and sanitation are poor and inadequate. Pre-school aged children (PSAC) have ... Keywords: Intestinal schistosomiasis prevalence, Pre-school children, Rwanda. Background. Schistosomiasis is a .... facilities (Republic of Rwanda, 2012). Study design and population.
incidence of schistosomiasis was 64%. Exposure of triathletes to fresh-water dam swimming in Zimbabwe ... Humans may become infected with schistosomiasis by bathing, wading or immersing limbs in infested ... questionnaire enquiring about other recreational activities in fresh water, and whether they had recently (in the ...
Rashad S. Barsoum
Full Text Available The clinical manifestations of schistosomiasis pass by acute, sub acute and chronic stages that mirror the immune response to infection. The later includes in succession innate, TH1 and TH2 adaptive stages, with an ultimate establishment of concomitant immunity. Some patients may also develop late complications, or suffer the sequelae of co-infection with other parasites, bacteria or viruses. Acute manifestations are species-independent; occur during the early stages of invasion and migration, where infection-naivety and the host’s racial and genetic setting play a major role. Sub acute manifestations occur after maturity of the parasite and settlement in target organs. They are related to the formation of granulomata around eggs or dead worms, primarily in the lower urinary tract with Schistosoma haematobium, and the colon and rectum with Schistosoma mansoni, Schistosoma japonicum, Schistosoma intercalatum and Schistosoma mekongi infection. Secondary manifestations during this stage may occur in the kidneys, liver, lungs or other ectopic sites. Chronic morbidity is attributed to the healing of granulomata by fibrosis and calcification at the sites of oval entrapment, deposition of schistosomal antigen-antibody complexes in the renal glomeruli or the development of secondary amyloidosis. Malignancy may complicate the chronic lesions in the urinary bladder or colon. Co-infection with salmonella or hepatitis viruses B or C may confound the clinical picture of schistosomiasis, while the latter may have a negative impact on the course of other co-infections as malaria, leishmaniasis and HIV. Prevention of schistosomiasis is basically geared around education and periodic mass treatment, an effective vaccine being still experimental. Praziquantel is the drug of choice in the treatment of active infection by any species, with a cure rate of 80%. Other antischistosomal drugs include metrifonate for S. haematobium, oxamniquine for S. mansoni and
First described by Theodor Bilharz in 1851, Schistosoma haematobium, the worm responsible for urinary schistosomiasis, was a major health problem along the Nile Valley until the present days. Haematuria, the main symptom of this parasitic disease, was known and treated in Egyptian medical papyri since 1550 B.C. A relationship between haematuria and the god Seth was envisaged. Sir Marc Armand Ruffer, pioneer of paleopathology, found (1910) calcified Schistosoma eggs in Egyptian mummies of the xxth dynasty, establishing that bilharzia plagued ancient Egypt people. The ELISA method demonstrated the Schistosoma circulating anodic antigen in 45% of mummies studied.
Full Text Available The cases of five patients with unusual manifestations of acute schistosomiasis mansoni are described in this paper. One patient developed skin lesions, three displayed diverse lung involvement, and one presented pyogenic liver abscesses caused by Staphylococcus aureus
structured questionnaire. The degree of awareness stood at 94.75% though none of the respondents knew the causative agent of urinary schistosomiasis. The number of respondents that accepted involvement in one water-related activity or the ...
Ezeamama, Amara E.; He, Chun-La; Shen, Ye
chemotherapy (PCT) with praziquantel (PZQ)? This paper describes the process SCORE used to transform this question into a harmonized research protocol, the study design for answering this question, the village eligibility assessments and data resulting from the first year of the study. METHODS: Beginning......-aged children. Seven studies are currently being implemented in five African countries. During the first year, villages were screened for eligibility, and data were collected on prevalence and intensity of infection prior to randomisation and the implementation of different schemes of PZQ intervention...... strategies. RESULTS: These studies of different treatment schedules with PZQ will provide the most comprehensive data thus far on the optimal frequency and continuity of PCT for schistosomiasis infection and morbidity control. CONCLUSIONS: We expect that the study outcomes will provide data for decision...
Ai, Dong-Yun; Liu, Bu-Yun
This article describes the main approach of ecological civilization construction and great changes and achievements in the original schistosomiasis endemic areas, Yujiang County, Jiangxi Province. Ecological civilization is an important part of schistosomiasis control work.
Helleberg, Marie; Thybo, Sören
There is an increasing number of imported cases of schistosomiasis in Europe, but there are only few studies on the efficacy of praziquantel for the treatment of schistosomiasis in non-endemic settings.......There is an increasing number of imported cases of schistosomiasis in Europe, but there are only few studies on the efficacy of praziquantel for the treatment of schistosomiasis in non-endemic settings....
... to its preferred body part, depending on its species. These areas include the: Bladder Rectum Intestines Liver ... subtropical areas worldwide. Symptoms Symptoms vary with the species of worm and the phase of infection. Many ...
Bergquist, Robert; Zhou, Xiao-Nong; Rollinson, David; Reinhard-Rupp, Jutta; Klohe, Katharina
Historically, the target in the schistosomiasis control has shifted from infection to morbidity, then back to infection, but now as a public health problem, before moving on to transmission control. Currently, all endemic countries are encouraged to increase control efforts and move towards elimination as required by the World Health Organization (WHO) roadmap for the global control of the neglected tropical diseases (NTDs) and the WHA65.21 resolution issued by the World Health Assembly. However, schistosomiasis prevalence is still alarmingly high and the global number of disability-adjusted life years (DALYs) due to this infection has in fact increased due to inclusion of some 'subtle' clinical symptoms not previously counted. There is a need to restart and improve efforts to reach the elimination goal. To that end, the first conference of the Global Schistosomiasis Alliance (GSA) Research Working Group was held in mid-June 2016 in Shanghai, People's Republic of China. It reviewed current progress in schistosomiasis control and elimination, identified pressing operational research gaps that need to be addressed and discussed new tools and strategies required to make elimination a reality. The articles emanating from the lectures and discussions during this meeting, together with some additional invited papers, have been collected as a special issue of the 'Infectious Diseases of Poverty' entitled 'Schistosomiasis Research: Providing the Tools Needed for Elimination', consisting of 26 papers in all. This paper refers to these papers and discusses critical questions arising at the conference related to elimination of schistosomiasis. The currently most burning questions are the following: Can schistosomiasis be eliminated? Does it require better, more highly sensitive diagnostics? What is the role of preventive chemotherapy at the elimination stage? Is praziquantel sufficient or do we need new drugs? Contemplating these questions, it is felt that the heterogeneity
Full Text Available Preliminary studies of schistosomiasis in Indonesia were made in the late 1930's and the early 1940's. The first human case of S. japonicum was discovered by Muller and Tesch from the Lindu valley of Central Sulawesi (Celebes. Early epidemiological studies prior to World War II demonstrated that, in addition to man, wild deer and domestic dogs served as reservoir hosts, "and subsequent microscopic examination of adult worms from these mammals confirmed them to be S. japonicum. Although extensive snail surveys were conducted at that time, the molluscan host was not found. The schistosomiasis problem in Lindu Valley virtually remained dormant until the 1970's. In the 1970's there was a resurgence of interest in the epidemiology of schistosomiasis in Indonesia. A new schistosomiasis area in the Napu valley was discovered. During this period, the intermediate host, Oncomelania hupensis was found in the Lake Lindu valley. This confirmed that the uisease situation in Indonesia was, in fact, a form of classical oriental schistosomiasis similar in its biology and transmission to that found in the Philippines, Japan, and China. The molluscan host of S. japonicum in the Lake Lindu Valley was subsequently described as a new species, O. h. iindoensis, and is most similar to O. h. quadrasi, the vector host in the Philippines. The disease occurs now only in two very isolated areas, the Lake Lindu valley and Napu valley in Central Sulawesi.
Li, C.-R.; Tang, L.-L.; Niu, H.-B.; Zhou, X.-N.; Liu, Z.-Y.; Ma, L.-L.; Zhou, Y.-S.
Schistosomiasis is a parasitic disease that menaces human health. In terms of impact this disease is second only to malaria as the most devastating parasitic disease. Oncomelania hupensis is the unique intermediate host of Schistosoma, and hence monitoring and controlling of the number of oncomelania is key to reduce the risk of schistosomiasis transmission. Remote sensing technology can real-timely access the large-scale environmental factors related to oncomelania breeding and reproduction, such as temperature, moisture, vegetation, soil, and rainfall, and can also provide the efficient information to determine the location, area, and spread tendency of oncomelania. Many studies show that the correlation coefficient between oncomelania densities and remote sensing environmental factors depends largely on suitable and high quality remote sensing data used in retrieve environmental factors. Research achievements on retrieving environmental factors (which are related to the living, multiplying and transmission of oncomelania) by multi-source remote data are shown firstly, including: (a) Vegetation information (e.g., Modified Soil-Adjusted Vegetation Index, Normalized Difference Moisture Index, Fractional Vegetation Cover) extracted from optical remote sensing data, such as Landsat TM, HJ-1A/HSI image; (b) Surface temperature retrieval from Thermal Infrared (TIR) and passive-microwave remote sensing data; (c) Water region, soil moisture, forest height retrieval from synthetic aperture radar data, such as Envisat SAR, DLR's ESAR image. Base on which, the requirements of environmental factor accuracy for schistosomiasis monitoring will be analyzed and summarized. Our work on applying remote sensing technique to schistosomiasis monitoring is then presented. The fuzzy information theory is employed to analyze the sensitivity and feasibility relation between oncomelania densities and environmental factors. Then a mechanism model of predicting oncomelania distribution and
Kallestrup, Per; Zinyama, Rutendo; Gomo, Exnevia
There is evidence from experimental models that the praziquantel-induced clearance of schistosomiasis is dependent on the host's immune response. Consequently, human immunodeficiency virus (HIV)-related immunodeficiency may impair the effect of praziquantel treatment.......There is evidence from experimental models that the praziquantel-induced clearance of schistosomiasis is dependent on the host's immune response. Consequently, human immunodeficiency virus (HIV)-related immunodeficiency may impair the effect of praziquantel treatment....
prevalence 43.3%), while none of those who use pipe borne and bore-hole water exclusively was infected (p < 0.05). Key words: urinary schistosomiasis, prevalence, water sources. Journal of Medical Laboratory Science Vol.12(2) 2003: 47 - 51 ...
Objective: To assess the current state of schistosomiasis (Schistosoma haematobium and Schistosoma mansoni) in Taïbong Sub Division, in Mayo-Kani Division, an epidemiological survey was conducted from September to November 2014 in four government primary schools, to determine the prevalence of these human ...
The following intestinal parasites were found in stools with various prevalence: Schistosoma mansoni 0.1% (95% CI: 0% - 0.3%) and Ancylostoma duodenale 0.1% (95% CI: 0% - 0.2%). The prevalence of urinary schistosomiasis in the Centre and Plateau Central regions had been greatly reduced from the previous level in ...
Abstract: A study on perceptions and practices related to schistosomiasis was conducted among adult people in Ukerewe. Island, in north-western Tanzania where ... Symptoms such as swollen abdomen were associated with witchcraft and taboos such as smelling, seeing or killing a python. Treatment-seeking practices ...
cost, and simplicity. However, the sensitivity of this method is low particularly in areas of low endemicity, and low- infection intensities (e.g. in young children), and may be affected by day to day .... Schistosomiasis were assessed using logistic regression. ..... Transactions of the Royal Society of Tropical. Medicine and ...
Human schistosomiasis, commonly called “bilharziasis” after a German pathologist, Theodor Bilharz (who first discovered the parasitic agent in Egypt in 1851) is caused by parasitic trematode of the genus, Schistosoma. There are at least 19 varieties of schistosomes, of which five are pathogenic parasites of man: S.
BACKGROUND: Intestinal schistosomiasis caused by Schistosoma mansoni(S. mansoni) infection is a widely distributed disease in several localities of Ethiopia. However, very limited information is available on the level of community's awareness about the disease. The aim of this study was to assess community's ...
This study on the prevalence of urinary schistosomiasis and concomitant urinary tract pathogens was carried out between August and December, 1998, among school children in Ibadan North Local Government Area. Terminal urine sample collected from only pupils in classes 3 to 6 for the study were analyzed accordingly ...
91 No. 7 July 2014. COMMUNITY PERCEPTIONS OF SCHISTOSOMIASIS TRANSMISSION, PREVALENCE AND CONTROL IN RELATION ..... yacinth. & hippo grass. W ater H yacinth. & ambatch trees. W ater H yacinth. & reeds. W ater H yacinth h/grass & reeds. H ippo grass. A mbatch tree. A mbatch tree &. R eeds. R eeds.
deployedto assess associated risk factors among infected children. Out of the examined children, ... health problem, and to a great extent children of 10-14 years age group were responsible in the transmission and ... Although several epidemiological studies for intestinal schistosomiasis due to S. mansoni infection were ...
A study on the prevalence of schistosomiasis infection was carried out among primary schools pupils in Awgu LGA, Enugu State, Nigeria. The primary schools include; Central Primary School Agbaogugu, Akegbi Primary School, Ogbaku Primary School, Ihe Primary School and Owelli-Court Primary School between ...
Schistosomiasis is a helminthic worm infection that affects 260 million people worldwide, 90% of whom live in sub-Saharan Africa. In Tanzania, where the research in this thesis was conducted, two species of schistosomes are highly endemic (Schistosoma haematobium and S. mansoni), with more than 50%
Introduction:A school based rapid survey was conducted th th from the 17 to the 19 of May 2011in Zambezi District of. Zambia to determine the prevalence and coinfection rate of malaria, hookworm and schistosomiasis in schoolchildren in other to inform decision maker. Methodology: The study design, sampling methods,.
Full Text Available Endemic in major parts of Africa and Middle East, Schistosoma haematobium is a common cause of recurrent urogenital infections and obstetric complications such as spontaneous abortions, ectopic pregnancies, and low birth weight babies. The involvement of fallopian tubes is not rare in endemic areas and may predispose to ectopic pregnancy and infertility. Indian subcontinent is a very lowrisk region for schistosoma infection. Tubal schistosomiasis is not exceptional in endemic zones, but is rarely found in India. The species most often isolated is S. haematobium. Contamination occurs via vascular anastomoses between the bladder and the genital organs. We report a case of tubal schistosomiasis presenting as ruptured ectopic pregnancy discovered on a surgical specimen after salpingectomy.
Kotzé, Sebastian Ranzi; Zinyama-Gutsire, Rutendo; Kallestrup, Per
BACKGROUND: Vitamin A has widespread effects on immune function and is therefore interesting in HIV-infection. Retinol-binding protein (RBP or RBP4) is a negative acute-phase protein and a marker of vitamin A status. Our aim was to investigate the association of RBP with HIV progression, infection...... with schistosomiasis, inflammatory cytokines, and mortality. METHODS: The study included 192 HIV-infected and 177 HIV-uninfected individuals from Mupfure in rural Zimbabwe. Of these, 208 were infected with Schistosoma haematobium, 27 with S. mansoni and 48 with both. Plasma RBP, HIV-RNA, CD4 cell count, haemoglobin......, cytokines, clinical staging (CDC category), self-reported level of function (Karnoffsky Performance Score, KPS) and schistosomiasis status were assessed at baseline. Participants were followed up for survival 3-4 years post-enrolment. RESULTS: RBP levels were lower in HIV-infected individuals(p
schistosomiasis, we are actually referring to three distinct diseases caused by three different species to helmninth parasites: Schistosoma mansoni, S...African dams in human terms, we need to consider the communities of people and animals that had to be resettled to make way for them: 75,000 people in the...the flies and mosquitoes that spread parasitic infections. Moved into new areas, people and their animals have been exposed to local disease-causing
Sallam, J A; Wright, S G
Schistosomiasis is a major public health problem in Yemen. In 1922 Schistosomiasis mansoni was first reported to be found in Yemeni patients. In 1951 the first population survey was carried out in Taiz and revealed the presence of Biomphalaria biossyi arabica where 35% of the snails were heavily infected with S. mansoni and in San'a no snails were infected. Although S. mansoni and S. hematobium infections have been found in most parts of Yemen Arab Republic (YAR) it seems that the disease is not a public health problem in some parts of the country such as Hodeidah, Al-Beidah, Mareb, and Al-Gouff. The source of S. mansoni and S. hematobium in Yemen was attributed to the continual migration of infected persons from Eritrea and other countries of East Africa to Yemen. The prevalence of infection is higher in rural than in urban areas. The complications of S. mansoni, notably portal hypertension, esophageal varices, and hematemesis have become a major clinical problem. The availability of Praziquantel as a safe and effective treatment makes case findings and treatment an important part of schistosomiasis control. Control of the disease also requires field studies followed by mollusciding, improvement of water supply and sanitation and, perhaps most importantly, health education.
Edward T. Chiyaka
Full Text Available Schistosomiasis infection is characterized by the presence of adult worms in the portal and mesenteric veins of humans as part of a complex migratory cycle initiated by cutaneous penetration of the cercariae shed by infected freshwater snails. The drug praziquantel is not always effective in the treatment against schistosomiasis at larvae stage. However, our simulations show that it is effective against mature worms and eggs. As a result, the study and understanding of immunological responses is key in understanding parasite dynamics. We therefore introduce quantitative interpretations of human immunological responses of the disease to formulate mathematical models for the within-host dynamics of schistosomiasis. We also use numerical simulations to demonstrate that it is the level of T cells that differentiates between either an effective immune response or some degree of infection. These cells are responsible for the differentiation and recruitment of eosinophils that are instrumental in clearing the parasite. From the model analysis, we conclude that control of infection is much attributed to the value of a function f, a measure of the average number of larvae penetrating a susceptible individual having hatched from an egg released by an infected individual. This agrees with evidence that there is a close association between the ecology, the distribution of infection and the disease.
Leucocyte migration- and bactericidal- indices were determined to establish the effect of sera from urinary schistosomiasis subjects on host defense mechanism. Both leucocyte migration and bacterial activity were diminished by sera from 66% of children with untreated urinary schistosomiasis subjects (uUSS), 25% of ...
Humans infected with Schistosoma parasite demonstrate substantial immune responses against both the ... Nigeria, urinary schistosomiasis is known to have. ~ existed from time immemorial and might have been .... larly elevated levels of IgG 1 , IgA and IgE in urinary schistosomiasis are associated with Th2 responses.
These parasites cause hepatosplenic and hepatointestinal schistosomiasis associated with significant morbidity and mortality especially in children and young people. We report a case of middle aged northern Nigerian farmer who had gastric schistosomiasis that mimicked an ulcerated gastric tumor at endoscopy with good ...
This paper examines the effects of the prevalence of urinary schistosomiasis infection on the socio-economic health of irrigation farmers in the rural districts of Kazaure Area, Northern Nigeria. It first reviews some general consideration of irrigation environment and schistosomiasis, its major associated health problem.
2 UNCLASSIFIED DAMDi7-95-C-5209 F/ G 6/15 UL 11 j j . 11_. W-I - - % (*J~f ~ HP OlIC FILE COPY *AD "Testing of Compounds for Efficacy Against...Liang, Y.S., 1974. Cultivation of Bulinus (5hy Q pis) g2.kous (Morelet) and BiQmphalaria pfeiffri pfeifferi (Krauss), snail hosts of schistosomiasis...Digenea). flacQ1. g " 11:225:280. 10. Sandt, D.G., Bruce, H.I. and Radke, M.G., 1965. A system for mass producing the snail Ausatra1Qbjiz Lbi.atus and
Preston, J. M.; Nelson, G. S.; Saeed, A. A.
Previous studies have shown that when cattle are exposed to cercariae of Schistosoma mansoni they develop considerable resistance to subsequent challenge with S. mattheei. The present study showed that when sheep are immunized with S. mansoni cercariae they too develop a marked resistance to subsequent challenge with S. mattheei. A small proportion of the immunizing cercariae reached maturity and a few viable S. mansoni eggs were found in the faeces of the sheep. The results of this experiment provide further evidence that heterologous immunity may be of significance in limiting the severity of schistosomiasis in both man and domestic animals in areas where animal and human schistosomes occur together. PMID:4540678
Moses J. Chimbari
Full Text Available Schistosoma haematobium and Schistosoma mansoni are prevalent in Zimbabwe to levels that make schistosomiasis a public health problem. Following three national surveys to map the disease prevalence, a national policy on control of schistosomiasis and soil transmitted helminths is being developed. This paper reviews the experiences that Zimbabwe has in the area of schistosomiasis control with a view to influence policy. A case study approach to highlight key experiences and outcomes was adopted. The benefits derived from intersectoral collaboration that led to the development of a model irrigation scheme that incorporates schistosomiasis control measures are highlighted. Similarly, the benefits of using plant molluscicides and fish and duck biological agents (Sargochromis codringtonii and Cairina moschata are highlighted. Emphasis was also placed on the importance of utilizing locally developed water and sanitation technologies and the critical human resource base in the area of schistosomiasis developed over years. After synthesis of the case studies presented, it was concluded that while there is a need to follow the WHO recommended guidelines for schistosomiasis control it is important to develop a control strategy that is informed by work already done in the country. The importance of having a policy and local guidelines for schistosomiasis control is emphasized.
Pamela Sabina Mbabazi
Full Text Available Urogenital schistosomiasis, caused by infection with Schistosoma haematobium, is widespread and causes substantial morbidity on the African continent. The infection has been suggested as an unrecognized risk factor for incident HIV infection. Current guidelines recommend preventive chemotherapy, using praziquantel as a public health tool, to avert morbidity due to schistosomiasis. In individuals of reproductive age, urogenital schistosomiasis remains highly prevalent and, likely, underdiagnosed. This comprehensive literature review was undertaken to examine the evidence for a cause-effect relationship between urogenital schistosomiasis and HIV/AIDS. The review aims to support discussions of urogenital schistosomiasis as a neglected yet urgent public health challenge.We conducted a systematic search of the literature including online databases, clinical guidelines, and current medical textbooks. We describe plausible local and systemic mechanisms by which Schistosoma haematobium infection could increase the risk of HIV acquisition in both women and men. We also detail the effects of S. haematobium infection on the progression and transmissibility of HIV in co-infected individuals. We briefly summarize available evidence on the immunomodulatory effects of chronic schistosomiasis and the implications this might have for populations at high risk of both schistosomiasis and HIV.Studies support the hypothesis that urogenital schistosomiasis in women and men constitutes a significant risk factor for HIV acquisition due both to local genital tract and global immunological effects. In those who become HIV-infected, schistosomal co-infection may accelerate HIV disease progression and facilitate viral transmission to sexual partners. Establishing effective prevention strategies using praziquantel, including better definition of treatment age, duration, and frequency of treatment for urogenital schistosomiasis, is an important public health priority. Our
Wang, Wei-Chun; Zhan, Ti; Zhu, Ying-Fu
To make various schistosomiasis epidemic maps based on Google Earth. The various elements for schistosomiasis epidemic maps were marked in the Google Earth platform by adding the place mark, path, polygon, overlay and so on. Various schistosomiasis epidemic maps were produced and saved, such as the schistosomiasis epidemic area map of the city, the map of Oncomelania hupensis snail distribution in the town, and the schematic map of snail environments. The schistosomiasis epidemic maps based on Google Earth are clear and visual. The production process is very simple and easy to learn. It is suitable for the use in the grass-root schistosomiasis control stations.
2, .... In each local government, school children were screened during school hours. However, pre-school children in the communities were screened in the house of community heads. ..... Few studies have dealt with urinary schistosomiasis.
Ivoire, from April to September. 2001 .... Those results indicated significant influence of irrigated rice growing on the transmission of urinary schistosomiasis in savannah areas. (Niakaramandougou). .... Burkina Faso, Benin, Cape Verde, Côte.
Sohn, I.G.; Kornicker, L.S.
An ostracod species of Cypretta is an effective predator in laboratory experiments on 1- to 3-day-old Biomphalaria glabrata, a vector snail of the blood fluke that causes the tropical and subtropical disease schistosomiasis.
Rashida M.R. Barakat
Full Text Available Schistosomiasis is a parasitic disease caused by blood flukes (Trematodes of the genus Schistosoma (S.. It is well documented that schistosomiasis haematobium was endemic in Ancient Egypt. Infection was diagnosed in mummies 3000, 4000 and 5000 years old. Scott was the first to describe the pattern of schistosomiasis infection in Egypt. Schistosomiasis haematobium was highly prevalent (60% both in the Nile Delta and Nile Valley South of Cairo in districts of perennial irrigation while it was low (6% in districts of basin irrigation. Schistosoma mansoni infected 60% of the population in the Northern and Eastern parts of the Nile Delta and only 6% in the Southern part. Neither S. mansoni cases nor its snail intermediate host were found in the Nile Valley South of Cairo. The building of the Aswan High Dam -which was completed in 1967 – did not cause any increase in schistosomiasis prevalence. In 1990, a study conducted in nine governorates of Egypt confirmed the change in the pattern of schistosomiasis transmission in the Delta. There was an overall reduction in S. mansoni prevalence while Schistosoma haematobium had continued to disappear. In Middle and Upper Egypt there was consistent reduction in the prevalence of S. haematobium except in Sohag, Qena, and Aswan governorates. However, foci of S. mansoni were detected in Giza, Fayoum, Menya and Assiut. All schistosomiasis control projects implemented in Egypt from 1953 to 1985 adopted the strategy of transmission control and were based mainly on snail control supplemented by anti-bilharzial chemotherapy. In 1997, the National Schistosomiasis Control Program (NSCP was launched in the Nile Delta. It adopted morbidity control strategy with Praziquantel mass treatment as the main component. In 1996, before the NSCP, 168 villages had S. mansoni prevalence >30%, 324 villages 20–30% and 654 villages 10–20%. By the end of 2010, in the whole country only 29 villages had prevalence >3% and none had
José Roberto Lambertucci
Full Text Available Acute schistosomiasis is a systemic hypersensitivity reaction against the migrating schistosomula and eggs. A variety of clinical manifestations appear during the migration of schistosomes in humans: cercarial dermatitis, fever, pneumonia, diarrhoea, hepatomegaly, splenomegaly, skin lesions, liver abscesses, brain tumours and myeloradiculopathy. Hypereosinophilia is common and aids diagnosis. The disease has been overlooked, misdiagnosed, underestimated and underreported in endemic areas, but risk groups are well known, including military recruits, some religious congregations, rural tourists and people practicing recreational water sports. Serology may help in diagnosis, but the finding of necrotic-exudative granulomata in a liver biopsy specimen is pathognomonic. Differentials include malaria, tuberculosis, typhoid fever, kala-azar, prolonged Salmonella bacteraemia, lymphoma, toxocariasis, liver abscesses and fever of undetermined origin. For symptomatic hospitalised patients, treatment with steroids and schistosomicides is recommended. Treatment is curative in those timely diagnosed.
Full Text Available This paper reports on the findings of a survey on OCI storage in people in Bahia, Brasil. In this survey 11 samples of adipose tissue were taken from people who underwent splenectomy for hepato splenic schistosomiasis. In these patients, total DDT averaged 10.66 ppm as compared to 4,83 ppm of total DDT found in presumably healthy people. The difference was statistically significant. It is considered that the increased DDT storage in patients with hepatosplenic schistosomiass may be the result of a reduced metabolzation of p,p'-DDT and reduced excretion of its metabolites. Another possíbility is the increased exposure to organochlorine nsectedes by hepatosplenc patients who frequently come from irrigation zones, where these compounds are more used in intensive cultivatíon.
Xue, Jing-bo; Zhang, Li-juan; Wang, Qiang; Lu, Yan-xin; Li, Shi-zhu
Schistosomiasis is closely related to environmental factors, the changes of environmental factors, such as vegetation, temperature, hydrology and soil, could impact the transmission of the disease. The environmental factors associated with schistosomiasis could be extracted by remote sensing technology quickly and precisely, and be applied to monitor the schistosomiasis transmission. The studies on high resolution remote sensing technology applied in the research of schistosomiasis are reviewed in this paper.
Uysal, H Kirkoyun; Akgul, O; Aliyev, E; Tunc, M H; Oner, Y A
Schistosomiasis is a chronic, parasitic disease and is endemic in some countries, primarily in Africa, Latin America and Asia. In some regions, Schistosoma haematobium is one of the principal causes of haematuria. In Turkey, due to the increasing amount of travel to and from endemic regions, the number of cases is also rising. We report a case of a 22-year-old Nigerian male who was admitted to our hospital with haematuria. Direct microbiological examination revealed S. haematobium eggs in his urine specimen. Schistosomiasis was diagnosed by pathology testing. Schistosomiasis has not been seen frequently in Turkey, and we therefore discuss the epidemiology, treatment options and clinical importance of S. haematobium. Copyright © 2013 Elsevier Ltd. All rights reserved.
Full Text Available Schistosomiasis is a neglected tropical disease of humans, and it is considered to be the second most devastating parasitic disease after malaria. Eggs produced by normally developed female worms are important in the transmission of the parasite, and they responsible for the pathogenesis of schistosomiasis. The tumor suppressor gene lethal giant larvae (lgl has an essential function in establishing apical-basal cell polarity, cell proliferation, differentiation, and tissue organization. In our earlier study, downregulation of the lgl gene induced a significant reduction in the egg hatching rate of Schistosoma japonicum (Sj eggs. In this study, the Sjlgl gene was used as a vaccine candidate against schistosomiasis, and vaccination achieved and maintained a stable reduction of the egg hatching rate, which is consistent with previous studies, in addition to reducing the worm burden and liver egg burden in some trials.
Eridan M Coutinho
Full Text Available In this paper, four different approaches attempting to reproduce the schistosomal liver fibrosis in undernourished mice are reported: shifting from a deficient to a balanced diet and vice-versa, repeated infections, influence of the genetic background, and immunological response. Infections were performed with 30 cercariae of Schistosoma mansoni and lasted at least four months. Undernourished mice were unable to reproduce the picture of "pipestem" fibrosis, except the C57 BL/10 inbred strain, four out of 21 mice developing the liver lesion. A link of this histological finding to the type of parasite strain can not be discarded at the moment. Repeated infections increased collagen deposition mainly in well nourished animals (seven out of 16 Swiss mice developed "pipestem"-like fibrosis. In undernourished infected Swiss mice the serum levels of soluble egg antigen specific antibodies IgG1, IgG2a, IgG2b, and IgG3 were two to four times lower than those detected for well nourished controls. The decreased humoral immune response coupled to the morphological, morphometric, and biochemical results reinforce the influence of the host nutritional status on the connective tissue changes of hepatic schistosomiasis.
John I. Bruce
Full Text Available Drug resistance associated with the treatment of human schistosomiasis appears to be an emerging problem requiring more attention from the scientific community than the subject currently receives. Drug-resistant strains of Schistosoma mansoni have been isolated by various investigators as a result of laboratory experimentation or from a combination of field and laboratory studies. Review of this data appears to indicate that the lack of susceptibility observed for some of the isolated strains cannot be ascribed solely to previous administration of antischistosome drugs and thus further studies are required to elucidate this phenomena. Strains of S. mansoni have now been identified from Brazil which are resistant to oxamniquine, hycanthone and niridazole; from Puerto Rico which are resistant to hycanthone and oxamniquine; and from Kenya which are resistant to niridazole and probably oxamniquine. Strains derived by in vitro selection and resistant to oxamniquine and possibly to oltipraz are also available. All of these strains are currently maintained in the laboratory in snails and mice, thus providing for the first time an opportunity for indepth comparative studies. Preliminary data indicates that S. haematobium strains resistant to metrifonate may be occurring in Kenya. This problem could poise great difficulty in the eventual development of antischistosomal agents. Biomphalaria glabrata from Puerto Rico and Brazil were found to be susceptible to drug-resistant S. mansoni from each country.
Amin, M. A.; Nelson, G. S.; Saoud, M. F. A.
Previous studies on heterologous immunity in mice have indicated that Schistosoma bovis and S. mattheei could be used to limit the severity of infection resulting from subsequent challenge by S. mansoni. These observations have now been extended to study the immunizing effect in rhesus monkeys of both S. mattheei and S. bovis. The bovine schistosomes were shown to be relatively non-pathogenic in rhesus monkeys. Immunization with 1000-2000 cercariae resulted in a marked reduction in the pathogenic effect of subsequent challenge with S. mansoni. This effect was demonstrated by a decrease in the worm load and tissue egg densities in 10 immunized monkeys as compared with 5 control animals. There was no correlation between fluorescent antibody titres and the intensity of infection or the degree of acquired immunity. There was a cross-reaction between S. mansoni and the bovine schistosomes. It is suggested that natural heterologous immunity (zooprophylaxis) may be of considerable epidemiological importance in determining the severity of schistosomiasis in man. PMID:4970323
Vercruysse, J; Gabriel, S
The present paper reviews the available literature on the development of immunity to animal Schistosoma infections. The majority of the studies on animal schistosomiasis were performed in cattle and pigs and only Schistosoma mattheei, S. bovis and S. japonicum received particular attention, mainly because of their recognized veterinary significance or zoonotic aspect. Although it is an accepted fact that acquired resistance to Schistosoma is of major importance in the regulation of infection intensity in the field, almost nothing is yet known of either the nature of the antigens or of the immune mechanisms involved. The recent studies on immunity development focus in particular on the occurrence of maternal to foetal transfer of immunological substances related to animal Schistosoma infections and possible effects of these transfers on the immunity development of the foetus/newborn. Since congenital infections for Schistosoma species other than S. japonicum are extremely rare, the most plausible route for foetal contact is the transplacental or postnatal transfer of immunological substances. Prenatal transfers of specific antibodies and antigens via placental lesions and postnatal transfers via the colostrum were observed in cattle and pigs, and subsequent modifications of the immune response of the newborn were observed. Placental lesions induced by Schistosoma eggs could allow other pathogens to cross the placenta.
Massoud, J.; Nelson, G. S.
Experiments were carried out in mice, cattle, and sheep to investigate the possibility that heterologous immune reactions may occur between the schistosomes prevalent in man and domestic animals in Iran. Immunization with Ornithobilharzia turkestanicum from cattle produced a considerable degree of immunity in mice against challenge with Schistosoma bovis, S. haematobium, and S. mansoni. The results of immunizing cattle with O. turkestanicum, S. bovis, and S. haematobium were even more striking; there was a reduction of 30-40% in the number of adult worms and a proportionally greater reduction in the tissue egg counts. Sheep developed a less marked immunity. Supplementary experiments on homologous immunity showed that mice developed a considerable degree of immunity against S. bovis. The results of the heterologous immunity experiments with S. haematobium and S. bovis are of particular interest as both parasites often occur in the same area and are often transmitted by the same snail host, man and cattle being exposed to the cercariae of both species simultaneously. The reciprocal immunity produced by these infections may be mutually beneficial in limiting the severity of schistosomiasis in man and domestic animals in the endemic areas. PMID:4540679
Zhong, Liu-Hua; Tao, Heng-Ye; Jiang, Jun
The comprehensive schistosomiasis prevention and control strategy which relied mainly on Oncomelania snail control, schistosomiasis detection and chemotherapy in residents and livestock was carried out in Runzhou District, 2004-2011. There were no acute schistosomiasis patients for 7 years and no acute schistosomiasis occurred in livestock for 8 years. A total of 107 331 person-times were examined by the serological test and the number of positive cases was 843 (0.8%), and there were 796 person-times who received chemotherapy from 2004 to 2011. There were no infected snails for 2 successive years. Runzhou District achieved the criteria of schistosomiasis endemic control in 2007 and the criteria of schistosomiasis transmission interrupted in 2011. The comprehensive schistosomiasis prevention and control strategy is very effective in Runzhou District.
Ravindran, R; Lakshmanan, B; Ravishankar, C; Subramanian, H
This short communication reports the prevalence of visceral schistosomiasis by worm counts from the mesentery of domestic ruminants of the hilly district of Wayanad, located in Kerala, one of the states in South India. We found 57.3, 50, and 4.7% of cattle, buffaloes and goats, respectively, had visceral schistosomiasis upon slaughter at a municipal slaughter house in Kalpetta. Our findings show that the prevalence of Schistosoma spindale infection is very high in Wayanad in comparison to previous reports from this and neighboring countries.
Celina Maria Modena
Full Text Available The analysis of the intergenerational process of disease/health representations constitutes a requisite for the construction of projects and health education interventions. The objective of this work is to describe the meaning attributed to schistosomiasis in the family context. Twenty-one residents of an endemic area were interviewed. The interviews were submitted to content analysis. The results demonstrated different representations of the disease by the children, parents and grandparents. This paper discusses the differences in these representations and its impact in schistosomiasis control programs.
Full Text Available The undisputed, worldwide success of chemotherapy notwithstanding, schistosomiasis continues to defy control efforts in as much rapid reinfection demands repeated treatment, sometimes as often as once a year. There is thus a need for a complementary tool with effect for the longer term, notably a vaccine. International efforts in this direction have been ongoing for several decades but, until the recombinant DNA techniques were introduced, antigen production remained an unsurmountable bottleneck. Although animal experiments have been highly productive and are still much needed, they probably do not reflect the human situation adequately and real progress can not be expected until more is known about human immune responses to schistosome infection. It is well-known that irradiated cercariae consistently produce high levels of protection in experimental animals but, for various reasons, this proof of principle cannot be directly exploited. Research has instead been focussed on the identification and testing of specific schistosome antigens. This work has been quite successful and is already at the stage where clinical trials are called for. Preliminary results from coordinated in vitro laboratory and field epidemiological studies regarding the protective potential of several antigens support the initiation of such trials. A series of meetings, organized earlier this year in Cairo, Egypt, reviewed recent progress, selecteded suitable vaccine candidates and made firm recommendations for future action including pledging support for large-scale production according to good manufacturing practice (GMP and Phase I trials. Scientists at the American Centers for Disease Control and Prevention (CDC have drawn up a detailed research plan. The major financial support will come from USAID, Cairo, which has established a scientific advisory group of Egyptian scientists and representatives from current and previous international donors such as WHO, NIAID, the
Takougang, Innocent; Meli, Jean; Fotso, Siméon; Angwafo, Fru; Kamajeu, Raoul; Ndumbe, Peter M
The present study was designed to assess the perceptions of hematuria, the most conspicuous sign of urinary schistosomiasis, in selected communities of the sudano-sahelian zone of Cameroon. Study questionnaires related to knowledge, beliefs and stigma associated with hematuria were administered to 964 pupils from 15 randomly selected schools. In order to ascertain children perceptions, we interviewed 143 adults living less than 2 kilometers from the target school. School children provided urine samples that were examined using the dip stick and sedimentation methods. Exposure to sun was the most reported cause of hematuria (53% adult and 62% children respondents), followed by drinking of dirty water (18% adults and 41% children). Only 15% of adult and 26% school children could relate hematuria to wading, a common means of exposure to urinary schistosomiasis. More than half of the school children stated that hematuria was a sign of disease (56%). Few pupils perceived hematuria to be a sign of strength (6%), while others related it to puberty (30%). Most pupils (80%) reported that hematuria was preventable while others (20% ) ascribed it to witchcraft. Pupils reported that hematuria could be cured in the hospital (65%), by the traditional healer (21%), or by reading Holy Scriptures (14%). Some respondents (35% of adult, and 40% of school children) stated that it was shameful to have blood in urine. Almost half of the adult respondents and 26% of the school children reported that hematuria was contagious. Boys and girls had similar levels of oviuria (OR=0.79 p>0.05), but boys were 4 times more likely to report hematuria (OR= 3.62, p<0.001). There was a poor understanding of the means of exposure, transmission and treatment of hematuria. Some aspects of the perceptions of hematuria reported herein corroborate with previous studies carried out in Cameroon, Niger, Ghana, Kenya and Tanzania. They should be considered, together with other socioeconomic and cultural
Sady, Hany; Al-Mekhlafi, Hesham M; Atroosh, Wahib M; Al-Delaimy, Ahmed K; Nasr, Nabil A; Dawaki, Salwa; Al-Areeqi, Mona A; Ithoi, Init; Abdulsalam, Awatif M; Chua, Kek Heng; Surin, Johari
Schistosomiasis is highly prevalent in Yemen, with an estimated 3 million cases, particularly among rural communities. This community-based study aims to evaluate the knowledge, attitude and practices (KAP) on schistosomiasis among rural communities in Yemen. A cross-sectional study was carried out among 250 households from ten rural districts in Yemen. Overall, 400 children were screened for urogenital and intestinal schistosomiasis. Moreover, parents were interviewed using a pre-tested questionnaire to collect information about the demographic and socioeconomic information and their KAP concerning schistosomiasis. A total of 127 (31.8%) children were found to be excreting schistosome eggs in either their urine or faeces (22.5% S. haematobium and 8.0% S. mansoni). Although 92.4% of the respondents had heard about schistosomiasis, 49.8%, 68.0% and 47.2% had knowledge concerning the transmission, signs and symptoms, and prevention, respectively. In addition, 77.1% considered schistosomiasis as harmful while 48.5% believed that schistosomiasis could be prevented, albeit their practices to prevent infections were still inadequate. Significant associations between the KAP and age, education, employment status and household monthly income were reported (P Yemen was inadequate, and that this could be a challenging obstacle to the elimination of schistosomiasis in these communities. Besides the current mass drug administration, school and community-based health education regarding schistosomiasis is imperative among these communities to significantly reduce the transmission and morbidity of schistosomiasis.
The importance of animals in human schistosomiasis in South Africa. ... following exposureto animal or bird bilharzia are considered. it is concluded that, as regards animal schistosomes, at present only S. mattheei and a hybrid of S. mattheei and S. haematobium pose a potential threat to human health in South Africa.
Soil transmitted helminth infections and schistosomiasis in school age children in sub-Saharan Africa: Efficacy of chemotherapeutic intervention since World Health ... for regular treatment of school children, development of alternative antihelminthic drugs and vaccines, environmental control measures and health education.
Objective: In order to determine the presence of bilharzia parasites in the populations, an epidemiological study on urinary and intestinal schistosomiasis was conducted from 09 September 2012 to 14 June 2013 in three villages namely: Badadji, Ouro-Marey and Kakala in Mayo-Louti Sub-Division, North Region Cameroon.
This review assesses the possible impacts of climate change on the temporal and spatial distribution of schistosomiasis-transmitting snails with special emphasis on aestivation, and discusses the effect of schistosome infection on aestivation ability. The impacts of parasite development on snails, as well as physiological ...
M.J. van der Werf (Marieke)
textabstractSchistosomiasis is one of the most prevalent parasitic infections and an important public health problem in many developing countries. The main early symptom if Schistosoma haematobium infection is hematuria, and S. mansoni infection causes bloody diarrhea. Current estimates of the
A survey was conducted to determine the prevalence and intensity of urinary schistosomiasis in six communities in Ihitte Uboma Local Government Area of Imo State, Nigeria, between February and July 2005. Centrifuge concentration technique was employed in the analysis of urine for the eggs of Schistosoma ...
A survey was conducted to determine the prevalence and intensity of urinary schistosomiasis in seven communities in Oguta Local Government Area of Imo State, Nigeria. The standard centrifugation method of analysis of urine for the examination of schistosome ova was employed. Of the 997 urine specimens examined in ...
Jul 2, 2011 ... snails (Biomphalaria pfeifferi and. Biomphalaria sudanica) are responsible for the transmission of S. mansoni in the country (6). The former is the most ..... G, VanLieshout L. Schistosomiasis mansoni in school attenders and non- attenders in Northwest Ethiopia. Ethiop J. Health Dev 2001; 15(2):117-23. 17.
Full Text Available Schistosomiasis is a parasitic zoonosis caused by small trematode worms called schistosomes, amongst which Schistosoma japonicum (S. japonicum is endemic in Asia. In order to understand the schistosome-induced changes in the host metabolism so as to facilitate early diagnosis of schistosomiasis, we systematically investigated the dynamic metabolic responses of mice biofluids and liver tissues to S. japonicum infection for five weeks using (1H NMR spectroscopy in conjunction with multivariate data analysis. We were able to detect schistosomiasis at the third week post-infection, which was one week earlier than "gold standard" methods. We found that S. japonicum infection caused significant elevation of urinary 3-ureidopropionate, a uracil catabolic product, and disturbance of lipid metabolism, stimulation of glycolysis, depression of tricarboxylic acid cycle and disruption of gut microbiota regulations. We further found that the changes of 3-ureidopropionate and overall metabolic changes in both urinary and plasma samples were closely correlated with the time-course of disease progression. Furthermore, such changes together with liver tissue metabonome were clearly associated with the worm-burdens. These findings provided more insightful understandings of host biological responses to the infection and demonstrated that metabonomic analysis is potentially useful for early detection of schistosomiasis and comprehension of the mechanistic aspects of disease progression.
Aim: This study was conducted in an attempt to establish the prevalence of urinary schistosomiasis in relation to epidemiological factors among children in Buruku and Katsina-Ala local government areas, Benue, Nigeria. Materials and Methods: Urine filtration technique using polycarbonate membrane filters was employed ...
Massara, Cristiano Lara; Amaral, Graciela Larissa; Caldeira, Roberta Lima; Drummond, Sandra Costa; Enk, Martin Johannes; Carvalho, Omar dos Santos
This paper discusses schistosomiasis transmission in São José da Serra, a village with a population of 500 in the county of Jaboticatubas, Minas Gerais State, Brazil. The area receives thousands of visitors a year for ecotourism. The study was motivated by a case of acute schistosomiasis involving a couple that spent the 2007 Carnival (Mardi Gras) holiday in the area. Stool tests from 268 local residents (53.6% of the population) showed that 35 (13%) were positive for the infection. A comparison with a previous survey (2005) in the same location showed an increase in the schistosomiasis-positive rate from 9.6% to 12.5%, among the 56 individuals who participated in both surveys. A malacological survey of 65 Biomphalaria glabrata snails showed one specimen (1.5%) eliminating cercariae. In a similar survey in 2005, no positive snail specimens were found. The study indicates that active schistosomiasis transmission is occurring in the area, and that integrated educational programs are needed for both the local community and tourists.
Schistosomiasis, a parasitic disease caused by the blood fluke Schistosoma sp. became a serious public health problem in Ghana after the Volta River was dammed in Akosombo in 1964. The formation of the Kpong head pond, about 25 km below the Akosombo dam, as a result of a second dam built at Kpong became an ...
The present study was designed to assess the perceptions of hematuria, the most conspicuous sign of urinary schistosomiasis, in selected communities of the sudano-sahelian zone of Cameroon. Study questionnaires related to knowledge, beliefs and stigma associated with hematuria were administered to 964 pupils from ...
The data indicates that there is a high prevalence of urinary schistosomiasis in the community and a poor knowledge of the disease and means of transmission. Health education is recommended along with provision of safe water and proper sanitation facilities for the community as a first step in eradication of the disease.
Results: During present studies, buffalos naturally infected with Schistosomiasis were treated with Veronia anthelmintica (Kaliziri), with dose 75 mg/kg, 150 mg/kg and 225 mg/kg body weight respectively, and their impact on various parameters like eggs reduction, milk production, weight gain and feed intake was noted.
A study of the dynamics of health-care seeking-behaviour of people living in communities endemic for schistosomiasis was carried out in Borgu and Shagamu Local Government areas of Niger State and Ewekoro, Odeda and Abeokuta North Local Government Areas of Ogun State, Nigeria. Questionnaires were ...
Hymenolepis nana and Enterobius vermicularis. Conclusions: The study confirmed that schistosomiasis and STH infections were endemic at the study sites, but also suggested that the prevalences had declined compared to earlier reports. There is need for more surveys to be carried out to assess the current distribution.
Introduction. Schistosomes (blood flukes) are digenetic trematodes of the super family Schistoso- matoidea. They cause the disease schistoso- miasis, which is commonly called bilharziasis. The parasites undergo part of their developmental phase into infective forms in water borne planorbid snails. Hence, schistosomiasis ...
The prevalence of urinary schistosomiasis in Ikpeshi, a rural community of Edo State, Nigeria showed that 195(65%) out of 300 volunteers harboured Schistosoma haematobium ova in their urine. Eosinophiluria was markedly significant > 5 eosinophilic leucocyturia/hpf and reported among 250 (83.3%) inhabitants. Of these ...
Purpose: To evaluate the safety, pharmacological effect and mechanism of action of an antifibrotic compound, safironil (SAF)/praziquantel (PZQ) combination on reversal of liver fibrogenesis in chronic murine Schistosomiasis mansoni. Methods: The antifibrotic effect of 0.5, 1 and 2 mg/ml of SAF was evaluated in vitro ...
Cristiane Rúbia Ferreira
Full Text Available Schistosomiasis is one of the most common parasitic diseases, stillconsidered of public health significance. Acute schistosomiasis is of difficultdiagnosis and therefore has been overlooked, misdiagnosed, underestimatedand underreported in endemic areas. The delay between the exposure tocontaminated water and the initial symptoms may explain this challengingdiagnosis. Acute schistosomiasis is frequently reported in non-immuneindividuals while reinfection cases occurring in endemic areas is scarcelydocumented. The later usually shows a benign course but fatal cases do exist.The authors report a case of a young female patient, in the late puerperium,with a three-month history of weight loss, intermittent fever, cough, thoracicand abdominal pain and increased abdominal girth. Physical examinationshowed a tachycardia, tachypnea and hypotension. Laboratory tests showeda mild anemia, eosinophilia, and a slightly elevation of liver enzymes. Thoraxand abdominal multidetector computed tomography evidenced a diffuseand bilateral pulmonary micronodules and peritoneal and intestinal wallthickening. The patient progressed rapidly to hepatic insufficiency, and deathafter respiratory insufficiency. An autopsy was performed and the findingswere compatible with acute Schistosomiasis in a patient previously exposedto Schistosoma mansoni.
Urinary schistosomiasis is of great public health importance in developing countries. It has adverse economic and health implications on residents living in endemic areas. Various factors including human behaviour are known to play key role in the transmission of the disease. The knowledge of the levels of risk of infection ...
Background: Schistosomes and geohelminths are highly prevalent causing serious health problem in the tropics. School children carry the heaviest burden of morbidity due to intestinal helminths and schistosomiasis infections. The aim of this study was to determine the prevalence and intensity of the major intestinal ...
Al Abaidani, Idris; Al-Abri, Seif; Shaban, Mahmoud; Ghugey, Satish L; Al Kathery, Salem; Al-Mashikhi, Khalid; Garba, Amadou; Gabrielli, Albis Francesco
Intestinal schistosomiasis due to Schistosoma mansoni was first reported in Oman in 1979. We describe the trend in parasitological and serological prevalence of human infection with S. mansoni in the endemic area over the period 1982-2014, and the compliance of data generated by the national monitoring and evaluation system with schistosomiasis elimination criteria set by the Ministry of Health of Oman. Parasitological and serological assessments were carried out on population (mainly children) living in the area at risk for schistosomiasis in Dhofar, the country's only endemic Governorate, for a period of over 30 years. Kato-Katz thick smear and Indirect Haemagglutination Assay were the techniques employed. Data indicate a progressive decline in prevalence of S. mansoni throughout the 1980s and the 1990s, a recrudescence in the early 2000s, and a more marked decrease following the implementation of six rounds of mass treatment with praziquantel from 2007 to 2013. Latest parasitological prevalence (2011) was 0%, while latest serological prevalence (2014) was 0.11%. Transmission of schistosomiasis has reached very low levels in Oman. Elimination criteria established by the Ministry of Health of Oman (parasitological prevalence ≤ 1% and serological prevalence ≤ 5%) have been met since 2008. Further investigations are required to assess whether interruption of transmission has been achieved in some or all foci, in view of the establishment of a formal verification process under the auspices of WHO.
However, unlike malaria and hookworm infections, little is known on the role of urinary schistosomiasis in iron deficiency anemia. The objective of this study was to assess the prevalence of iron deficiency anemia and the effect of iron supplementation on hemoglobin (Hb) and serum ferritin (SF) levels among school children ...
... Once weekly iron supplementation can decrease S haematobium reinfection after 6 months and should be incorporated into school based schistosomiasis control programs in highly endemic areas. Clinical trials.gov identifier: NCT 00276224, sponsored by DBL-Institute for Health Research and Development, Denmark.
Results: The overall infection rates of schistosomiasis mansoni, trichuriasis, ascariasis and hookworm infection were 73.7%, 41.5%, 37.2% and 28.4%, respectively. Other parasitic infections observed were caused by Hymenolepis nana (1.7%), Taenia species (1.4%), and Enterobius vermicularis (1.4%). Children in the age ...
Other more rare STH infections noted were Ascaris lumbricoides, Hymenolepis nana and Enterobius vermicularis. Conclusions: The study confirmed that schistosomiasis and STH infections were endemic at the study sites, but also suggested that the prevalences had declined compared to earlier reports. There is need for ...
humans. Although schistosomiasis is not found in the. United States, over 200 million people are infected worldwide (1). Schistosomes belong to the kingdom ..... Activities the communities include fishing, swimming, wash and bathing. Majority of these activities took place the shallower portion of the water bodies usua.
Background: Information on epidemiology of schistosomiasis in school age children and particularly non school attenders are scanty in northwestern Ethiopia. Objective: To assess the prevalence of Schistosoma mansoni in school attenders and non-attenders in Northwest Ethiopia. Methods: A parasitological survey was ...
Background: Schistosomiasis mansoni and soil-transmitted helminthiasis (STHs) are considerable medical and public health problems in Ethiopia. However, information is limited on the epidemiology of these infections in different localities even though it is needed to plan effective prevention and control measures.
ABSTRACT. Background: Schistosomes and geohelminths are highly prevalent causing serious health problem in the tropics. School children carry the heaviest burden of morbidity due to intestinal helminths and schistosomiasis infections. The aim of this study was to determine the prevalence and intensity of the major.
Table 2: Prevalence and intensity of intestinal schistosomiasis and ascariasis using Kato-Katz method in 8 elementary schools in Adwa Town, northern Ethiopia, 2007. School. No. Examined. Positive for. Male. Female. Total no. examined. S. mansoni. A. lumbricoides. No. (%) epg. No. (%). Epg. May Guagua. 28. 22. 50.
Salawu, Oyetunde T; Odaibo, Alexander B
To assess the epidemiology of urogenital schistosomiasis among pregnant women in rural communities of southwestern Nigeria. The present cross-sectional epidemiologic survey of urogenital schistosomiasis was conducted during 2010-2011 among pregnant women in Yewa North Local Government, Ogun State, Nigeria. The women were microscopically screened for infection with Schistosoma haematobium. Of 313 volunteer participants, 20.8% tested positive for S. haematobium infection. The prevalence of infection was highest (31.5%) among women aged 20-24years. The infection intensity did not differ significantly between age groups (t=1.848, P=0.71). Primigravidae and women in the first trimester of pregnancy had the highest intensity of infection with 33.1 and 27.7 eggs/10mL of urine, respectively. There was an association between disease prevalence and parasite intensity across the age groups (χ(2)=68.82, P=0.02). The prevalence of S. haematobium was not associated with age or pregnancy trimester (P=0.06), but associations existed between intensity of infection and gravidity (P=0.001). The prevalence of urogenital schistosomiasis among pregnant women in Nigeria was high, with younger women and primigravidae at the greatest risk. These data can be used to develop a schistosomiasis control program among pregnant women in the study area. Copyright © 2013 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.
Journal of Biotechnology. 7 (16), 2773-2776. Uneke, C. J.; Oyibo, P. G.; Ugwuoru, C.D.C.; Nwanokwai, A. P.;. Iloegbunam, R. O. (2007): Urinary Schistosomiasis Among School. Age Children In Ebonyi State, Nigeria. The Internet Journal of. Laboratory Medicine. 2(1):1. Clennon, J. A., King, C. H., Muchiri, E. M, Kariuki, H. C., ...
Available online at http://www.ajol.info/index.php/njbas/index. Nigerian Journal of Basic and Applied Science (September, 2012), 20(3): 189-194. ISSN 0794-5698. Studies on Urinary Schistosomiasis in Selected Villages around Gusau Dam Site, Zamfara State,. Nigeria. *1M.U Ladan, 1U. Abubakar, 1K. Abdullahi, 1M.
Adema, Coen M; Hillier, Ladeana W; Jones, Catherine S
Biomphalaria snails are instrumental in transmission of the human blood fluke Schistosoma mansoni. With the World Health Organization's goal to eliminate schistosomiasis as a global health problem by 2025, there is now renewed emphasis on snail control. Here, we characterize the genome of Biompha...
,. Nigeria, Togo (Cunin et al., 2000; Audibert and Mathonnat, 2001; Moné et al., 2010;. Wallet et al., 2016). Many parts of West. African States have been a constant in the prevalence of malaria and schistosomiasis after six years of practice rice.
Abiola Fatimah Adenowo
Full Text Available Schistosomiasis, a neglected tropical disease of poverty ranks second among the most widespread parasitic disease in various nations in sub-Saharan Africa. Neglected tropical diseases are causes of about 534,000 deaths annually in sub-Saharan Africa and an estimated 57 million disability-adjusted life-years are lost annually due to the neglected tropical diseases. The neglected tropical diseases exert great health, social and ﬁnancial burden on economies of households and governments. Schistosomiasis has profound negative effects on child development, outcome of pregnancy, and agricultural productivity, thus a key reason why the "bottom 500 million" inhabitants of sub-Saharan Africa continue to live in poverty. In 2008, 17.5 million people were treated globally for schistosomiasis, 11.7 million of those treated were from sub-Saharan Africa. This enervating disease has been successfully eradicated in Japan, as well as in Tunisia. Morocco and some Caribbean Island countries have made signiﬁcant progress on control and management of this disease. Brazil, China and Egypt are taking steps towards elimination of the disease, while most sub-Saharan countries are still groaning under the burden of the disease. Various factors are responsible for the continuous and persistent transmission of schistosomiasis in sub-Saharan Africa. These include climatic changes and global warming, proximity to water bodies, irrigation and dam construction as well as socio-economic factors such as occupational activities and poverty. The morbidity and mortality caused by this disease cannot be overemphasized. This review is an exposition of human schistosomiasis as it affects the inhabitants of various communities in sub-Sahara African countries. It is hoped this will bring a re-awakening towards efforts to combat this impoverishing disease in terms of vaccines development, alternative drug design, as well as new point-of-care diagnostics.
Adenowo, Abiola Fatimah; Oyinloye, Babatunji Emmanuel; Ogunyinka, Bolajoko Idiat; Kappo, Abidemi Paul
Schistosomiasis, a neglected tropical disease of poverty ranks second among the most widespread parasitic disease in various nations in sub-Saharan Africa. Neglected tropical diseases are causes of about 534,000 deaths annually in sub-Saharan Africa and an estimated 57 million disability-adjusted life-years are lost annually due to the neglected tropical diseases. The neglected tropical diseases exert great health, social and financial burden on economies of households and governments. Schistosomiasis has profound negative effects on child development, outcome of pregnancy, and agricultural productivity, thus a key reason why the "bottom 500 million" inhabitants of sub-Saharan Africa continue to live in poverty. In 2008, 17.5 million people were treated globally for schistosomiasis, 11.7 million of those treated were from sub-Saharan Africa. This enervating disease has been successfully eradicated in Japan, as well as in Tunisia. Morocco and some Caribbean Island countries have made significant progress on control and management of this disease. Brazil, China and Egypt are taking steps towards elimination of the disease, while most sub-Saharan countries are still groaning under the burden of the disease. Various factors are responsible for the continuous and persistent transmission of schistosomiasis in sub-Saharan Africa. These include climatic changes and global warming, proximity to water bodies, irrigation and dam construction as well as socio-economic factors such as occupational activities and poverty. The morbidity and mortality caused by this disease cannot be overemphasized. This review is an exposition of human schistosomiasis as it affects the inhabitants of various communities in sub-Sahara African countries. It is hoped this will bring a re-awakening towards efforts to combat this impoverishing disease in terms of vaccines development, alternative drug design, as well as new point-of-care diagnostics. Copyright © 2015 Elsevier Editora Ltda. All rights
Abiola Fatimah Adenowo
Full Text Available Schistosomiasis, a neglected tropical disease of poverty ranks second among the most widespread parasitic disease in various nations in sub-Saharan Africa. Neglected tropical diseases are causes of about 534,000 deaths annually in sub-Saharan Africa and an estimated 57 million disability-adjusted life-years are lost annually due to the neglected tropical diseases. The neglected tropical diseases exert great health, social and financial burden on economies of households and governments. Schistosomiasis has profound negative effects on child development, outcome of pregnancy, and agricultural productivity, thus a key reason why the “bottom 500 million” inhabitants of sub-Saharan Africa continue to live in poverty. In 2008, 17.5 million people were treated globally for schistosomiasis, 11.7 million of those treated were from sub-Saharan Africa. This enervating disease has been successfully eradicated in Japan, as well as in Tunisia. Morocco and some Caribbean Island countries have made significant progress on control and management of this disease. Brazil, China and Egypt are taking steps towards elimination of the disease, while most sub-Saharan countries are still groaning under the burden of the disease. Various factors are responsible for the continuous and persistent transmission of schistosomiasis in sub-Saharan Africa. These include climatic changes and global warming, proximity to water bodies, irrigation and dam construction as well as socio-economic factors such as occupational activities and poverty. The morbidity and mortality caused by this disease cannot be overemphasized. This review is an exposition of human schistosomiasis as it affects the inhabitants of various communities in sub-Sahara African countries. It is hoped this will bring a re-awakening towards efforts to combat this impoverishing disease in terms of vaccines development, alternative drug design, as well as new point-of-care diagnostics.
Ørnbjerg, Niels; Simonsen, P. E.; Furu, Peter
trained personnel at the local, district and central levels. Training of health personnel as well as motivation of the community are fundamental and essential elements in any schistosomiasis control programme. The training elements and approaches are discussed.......Recently acquired comprehensive knowledge concerning the epidemiology of schistosomiasis has provided the background for the establishment of schistosomiasis control strategies. However, the planning, implementation, and maintenance of such control programmes requires sufficient numbers of well...
Mao, Yuan-Hua; Li, Dong; Ning, An; Qiu, Ling; Xiong, Ji-Jie
To develop the information management system for advanced schistosomiasis chemotherapy and assistance in Jiangxi Province. Based on Access 2003, the system was programmed by Visual Basic 6.0 and packaged by Setup Factory 8.0. In the system, advanced schistosomiasis data were able to be input, printed, indexed, and statistically analyzed. The system could be operated and maintained easily and timely. The information management system for advanced schistosomiasis chemotherapy and assistance in Jiangxi Province is successfully developed.
Fu, Jun; Leng, Cheng-mei; Tang, Min; Yao, Wei-gang
To understand the status of schistosomiasis of staff in the Hydrology Bureau of Yangtze Water Resources Committee and the Oncomelania hupensis snail condition of their work areas in 2013, so as to provide the evidences for the schistosomiasis control in the industry. The physical examination data about schistosomiasis of the staff from 2006 to 2013 were collected and analyzed to understand the schistosomiasis prevalence condition of the staff and the changes of their liver parenchyma. Meanwhile, the snail status in the work areas was surveyed. There were 1,393 staff involved in the physical examinations of schistosomiasis in 2003, 197 of them were schistosomiasis patients, the prevalence rate was 14.14%, and no new acute schistosomiasis case occurred. The cases whose liver parenchyma were classified as Grade 0, I , II , III occupied 28.9%, 67.0%, 3.05% and 1.02%, respectively. A total of 24 work areas were involved in the snail survey, and 71 snails were captured. Among the whole snails captured, 39 were living snails, but no schistosome infected snails were found. The prevalence rate of schistosomiasis in staff of the Hydrology Bureau of Yangtze Water Resources Committee is relatively high, so the schistosomiasis surveillance as well as the snail survey and control still should be carried out consistently.
Malone, John; Bergquist, Robert; Rinaldi, Laura; Xiao-nong, Zhou
Geographic information system (GIS) and remote sensing (RS) from Earth-observing satellites offer opportunities for rapid assessment of areas endemic for vector-borne diseases including estimates of populations at risk and guidance to intervention strategies. This presentation deals with GIS and RS applications for the control of schistosomiasis in China and the Philippines. It includes large-scale risk mapping including identification of suitable habitats for Oncomelania hupensis, the intermediate host snail of Schistosoma japonicum. Predictions of infection risk are discussed with reference to ecological transformations and the potential impact of climate change and the potential for long-term temperature increases in the North as well as the impact on rivers, lakes and water resource developments. Potential integration of geospatial mapping and modeling in schistosomiasis surveillance and response systems in Asia within Global Earth Observation System of Systems (GEOSS) guidelines in the health societal benefit area is discussed.
Full Text Available Egg-induced lesions in the upper and the lower female reproductive tract are important complications of the infection with Schistosoma mansoni. The understanding of the pathophysiology and pathology of genital lesions is only rudimentary, simple and reliable diagnostic tools are not at hand, epidemiological data do not exist and how to treat best the women affected, is not known. In view of recent advances in the understanding of genital lesions induced by S. haematobium the existing literature is critically analysized and possible consequences of female genital schistosomiasis are outlined. We estimate that 6 to 27 % girls and women with intestinal schistosomiasis, at least temporarily, suffer from pathology induced by eggs sequestered somewhere in their genital organs. This is a mattern of concern and warrants more research into the epidemiology, pathology, diagnosis and therapy of this disease entity.
K. H. Odubamowo
Full Text Available Background. The incidence of tubal ectopic gestation caused by schistosomiasis induced tubal pathology is undocumented in this environment, which may be due to rarity of this pathology. Bilateral tubal gestation is common in patients that have undergone in vitro fertilization. We report a hitherto undocumented case of spontaneous bilateral ectopic gestation following tubal schistosomiasis. Case Report. Mrs. OB was a 32-year-old G4P3+0 (3 alive woman who complained of abdominal pain and bleeding per vaginam of 4 and 2 days’ duration respectively following 8 weeks of amenorrhea. A clinical impression of ruptured ectopic gestation was confirmed by ultrasound scanning. She had bilateral salpingectomy with histology of specimens showing bilateral ectopic gestation with Schistosoma haematobium induced salpingitis (findings of Schistosoma haematobium ova noted on slide. Conclusion. Schistosoma induced salpingitis is a rare but possible cause of bilateral tubal gestation.
Full Text Available Geographic information system (GIS and remote sensing (RS from Earth-observing satellites offer opportunities for rapid assessment of areas endemic for vector-borne diseases including estimates of populations at risk and guidance to intervention strategies. This presentation deals with GIS and RS applications for the control of schistosomiasis in China and the Philippines. It includes large-scale risk mapping including identification of suitable habitats for Oncomelania hupensis, the intermediate host snail of Schistosoma japonicum. Predictions of infection risk are discussed with reference to ecological transformations and the potential impact of climate change and the potential for long-term temperature increases in the North as well as the impact on rivers, lakes and water resource developments. Potential integration of geospatial mapping and modeling in schistosomiasis surveillance and response systems in Asia within Global Earth Observation System of Systems (GEOSS guidelines in the health societal benefit area is discussed.
Zilton A Andrade
Full Text Available Specific chemotherapy against schistosomiasis together with environmental changes occurring in endemic areas of Brazil are causing a revolution in the clinico-pathological presentation of the disease when comparing to date from 10 to 15 years ago. To update the subject, an inquire was made among the most experienced Brazilian investigators in this field. They agree that a decrease of about 50 to 70% in prevalence, and an even higher decrease in incidence are taking place in Brazil today. The prevalence of schistosome-infection has decreased in some areas and increased in other, with spreading sometimes occurring to peri-urban regions, indicating that schistosomiasis control depends on the application of multiple measures. General clinical and pathological manifestations related to hepatosplenic disease, such as ascites, gastric hemorrhages, big-spleen syndrome, cor pulmonale, glomerulopathy, etc. are also less severe nowadays than they used to be in the past
More females (30.8%) than males (24.1%) were infected in all the age groups and high rate of hematuria (56.6%) was observed among the infected subjects. Prevalence of vesical schistosomiasis was significantly higher (77.9%) among those in the age group 11-20 years than those of 41-50 years (p<0.05). The intensity of ...
Luiz Arthur Calheiros Leite
Full Text Available Schistosomiasis mansoni is a chronic liver disease, in which some patients (5-10% progress to the most severe form, hepatosplenic schistosomiasis. This form is associated with portal hypertension and splenomegaly, and often episodes of gastrointestinal bleeding, even with liver function preserved. Splenectomy is a validated procedure to reduce portal hypertension following digestive bleeding. Here, we evaluate beneficial effects of splenectomy on blood coagulation factors and liver function tests in hepatosplenic schistosomiasis mansoni compared to non-operated patients.Forty-five patients who had undergone splenectomy surgery were assessed by laboratory analyses and ultrasound examination and compared to a non-operated group (n = 55. Blood samples were obtained for liver function tests, platelet count and prothrombin time. Coagulation factors (II, VII, VIII, IX and X, protein C and antithrombin IIa, plasminogen activator inhibitor-1 were measured by routine photometric, chromogenic or enzyme-linked immunosorbent assays, while hyperfibrinolysis was defined by plasminogen activator inhibitor-1 levels. Both groups had similar age, gender and pattern of periportal fibrosis. Splenectomized patients showed significant reductions in portal vein diameter, alkaline phosphatase and bilirubin levels compared to non-operated patients, while for coagulation factors there were significant improvement in prothrombin, partial thromboplastin times and higher levels of factor VII, VIII, IX, X, protein C and plasminogen activator inhibitor-1.This study shows that the decrease of flow pressure in portal circulation after splenectomy restores the capacity of hepatocyte synthesis, especially on the factor VII and protein C levels, and these findings suggest that portal hypertension in patients with hepatosplenic schistosomiasis influences liver functioning and the blood coagulation status.
The species name of Schistosoma intercalatum, Fischer 1934 is linked to the shape and the size of his eggs, which are intermediate between those of S. haematobium and S. bovis. S. intercalatum is the instrument of an intestinal form of schistosomiasis looking like the form induced by S. mansoni but characterized by a low location of the lesions, mainly situated at the rectum and sigmoid level. The spreading area of S. intercalatum is bound to Central Africa. The foci are often urban and of a size limited to a town district. Bulinus forskalii is the intermediate host mostly involved in transmitting S. intercalatum lower Guinea strain, which is the strain found in the largest number of foci. B. crystallinus too transmits the parasite in the area of Gamba in Gabon. The Central Basin congolese strain of S. intercalatum is transmitted by Bulinus globosus. The houses where inhabitants are voiding eggs of S. intercalatum are just in front of the river bank or stream which are snails'breeding places. S. intercalatum is expending at the present time because of the development of built-up areas which are characterized by a disorganized town-planning. The disease is due to the high faecal pollution of the environment, causing a contamination of the urban hydrographic network which is the setting of schistosomiasis transmission. Although primely linked to the forest area, S. intercalatum is spreading with deforestation. Coming from the savannah area, S. haematobium is now invading the forest area, entering into competition with S. intercalatum. But since Bulinus acting as intermediate hosts of S. haematobium are more heliophilous than Bulinus transmitting S. intercalatum, urinary schistosomiasis has a tendency to supplant recto-sigmoidal schistosomiasis, especially in foci where hybridization between the two species of schistosomes is occurring.
Daniele Silva de Moraes Van-Lume
Full Text Available OBJECTIVE: To perform a systematic review of the prevalence of the HCV/ S. mansoni co-infection and associated factors in Schistosoma mansoni -infected populations. METHODS: The bibliographic search was carried out using the Medline, Lilacs, SciELO, Cochrane Library and Ibecs databases. The criteria for the studies' selection and the extraction data were based on systematic review methods. Forty five studies were found, with nine being excluded in a first screening. Thirteen articles were used for data extraction. RESULTS: The HCV infection rates in schistosomiasis populations range from 1% in Ethiopia to 50% in Egypt. Several studies had poorly defined methodologies, even in areas characterized by an association between hepatitis C and schistosomiasis, such as Brazil and Egypt, which meant conclusions were inconsistent. HCV infection rates in schistosomotic populations were heterogeneous and risk factors for acquiring the virus varied widely. CONCLUSIONS: Despite the limitations, this review may help to identify regions with higher rates of hepatitis C and schistosomiasis association. However, more studies are necessary for the development of public health policies on prevention and control of both diseases.
Full Text Available The present work analyzes the epidemiology of schistosomiasis in Brazil, its expansion, the attempts to control the disease, and the overall difficulties. The authors present the distribution of schistosomiasis intermediary hosts in Brazil, the migration routes of the human population, and disease distribution in highly and lowly endemic areas and isolated foci. They also analyze the controlling programs developed from 1977 to 2002, indicating the prevalence evolution and the reduction of disease morbi-mortality. In addition, the authors also evaluate controlling methods and conclude that: (a no isolated method is able to control schistosomiasis, and every controlling program should consider the need of a multidisciplinary application of existing methods; (b in long term, basic sanitation, potable water supply, as well as sanitary education, and community effective participation are important for infection control; (c in short term, specific treatment at endemic areas, associated with control of intermediary hosts at epidemiologically important foci, are extremely relevant for controlling disease morbidity, although not enough for interrupting infection transmission.
Zhang, Zhijie; Zhu, Rong; Ward, Michael P; Xu, Wanghong; Zhang, Lijuan; Guo, Jiagang; Zhao, Fei; Jiang, Qingwu
The World Bank Loan Project (WBLP) for controlling schistosomiasis in China was implemented during 1992-2001. Its short-term impact has been assessed from non-spatial perspective, but its long-term impact remains unclear and a spatial evaluation has not previously been conducted. Here we compared the spatial distribution of schistosomiasis risk using national datasets in the lake and marshland regions from 1999-2001 and 2007-2008 to evaluate the long-term impact of WBLP strategy on China's schistosomiasis burden. A hierarchical Poisson regression model was developed in a Bayesian framework with spatially correlated and uncorrelated heterogeneities at the county-level, modeled using a conditional autoregressive prior structure and a spatially unstructured Gaussian distribution, respectively. There were two important findings from this study. The WBLP strategy was found to have a good short-term impact on schistosomiasis control, but its long-term impact was not ideal. It has successfully reduced the morbidity of schistosomiasis to a low level, but can not contribute further to China's schistosomiasis control because of the current low endemic level. A second finding is that the WBLP strategy could not effectively compress the spatial distribution of schistosomiasis risk. To achieve further reductions in schistosomiasis-affected areas, and for sustainable control, focusing on the intermediate host snail should become the next step to interrupt schistosomiasis transmission within the two most affected regions surrounding the Dongting and Poyang Lakes. Furthermore, in the lower reaches of the Yangtze River, the WBLP's morbidity control strategy may need to continue for some time until snails in the upriver provinces have been well controlled. It is difficult to further reduce morbidity due to schistosomiasis using a chemotherapy-based control strategy in the lake and marshland regions of China because of the current low endemic levels of infection. The future control
Full Text Available BACKGROUND: The World Bank Loan Project (WBLP for controlling schistosomiasis in China was implemented during 1992-2001. Its short-term impact has been assessed from non-spatial perspective, but its long-term impact remains unclear and a spatial evaluation has not previously been conducted. Here we compared the spatial distribution of schistosomiasis risk using national datasets in the lake and marshland regions from 1999-2001 and 2007-2008 to evaluate the long-term impact of WBLP strategy on China's schistosomiasis burden. METHODOLOGY/PRINCIPAL FINDINGS: A hierarchical Poisson regression model was developed in a Bayesian framework with spatially correlated and uncorrelated heterogeneities at the county-level, modeled using a conditional autoregressive prior structure and a spatially unstructured Gaussian distribution, respectively. There were two important findings from this study. The WBLP strategy was found to have a good short-term impact on schistosomiasis control, but its long-term impact was not ideal. It has successfully reduced the morbidity of schistosomiasis to a low level, but can not contribute further to China's schistosomiasis control because of the current low endemic level. A second finding is that the WBLP strategy could not effectively compress the spatial distribution of schistosomiasis risk. To achieve further reductions in schistosomiasis-affected areas, and for sustainable control, focusing on the intermediate host snail should become the next step to interrupt schistosomiasis transmission within the two most affected regions surrounding the Dongting and Poyang Lakes. Furthermore, in the lower reaches of the Yangtze River, the WBLP's morbidity control strategy may need to continue for some time until snails in the upriver provinces have been well controlled. CONCLUSION: It is difficult to further reduce morbidity due to schistosomiasis using a chemotherapy-based control strategy in the lake and marshland regions of China
Utzinger, Jürg; N'goran, Eliézer K; Caffrey, Conor R; Keiser, Jennifer
Compared to malaria, tuberculosis and HIV/AIDS, schistosomiasis remains a truly neglected tropical disease. Schistosomiasis, perhaps more than any other disease, is entrenched in prevailing social-ecological systems, since transmission is governed by human behaviour (e.g. open defecation and patterns of unprotected surface water contacts) and ecological features (e.g. living in close proximity to suitable freshwater bodies in which intermediate host snails proliferate). Moreover, schistosomiasis is intimately linked with poverty and the disease has spread to previously non-endemic areas as a result of demographic, ecological and engineering transformations. Importantly though, thanks to increased advocacy there is growing awareness, financial and technical support to control and eventually eliminate schistosomiasis as a public health problem at local, regional and global scales. The purpose of this review is to highlight recent progress made in innovation, validation and application of new tools and strategies for research and integrated control of schistosomiasis. First, we explain that schistosomiasis is deeply embedded in social-ecological systems and explore linkages with poverty. We then summarize and challenge global statistics, risk maps and burden estimates of human schistosomiasis. Discovery and development research pertaining to novel diagnostics and drugs forms the centrepiece of our review. We discuss unresolved issues and emerging opportunities for integrated and sustainable control of schistosomiasis and conclude with a series of research needs. Copyright © 2010 Elsevier B.V. All rights reserved.
on what the community knows about the infection and socio-cultural factors that influence community's perception about the disease, to make the control of schistosomiasis more effective and sustainable in endemic areas (6-12). In Ethiopia, a number of epidemiological studies showed that intestinal schistosomiasis due to ...
Edungbola, L D
Laboratory tests were conducted to determine the prophylactic effectiveness of 4-chloro-3, 5-xylenol (Dettol) against mammalian schistosomiasis. The findings showed that this antiseptic was capable of protecting the albino mice against Mansonian schistosomiasis and of acting as an effective miracidicide, cercaricide and molluscicide.
Erikstrup, Christian; Kallestrup, Per; Zinyama-Gutsire, Rutendo B L
We previously reported that treatment for schistosomiasis in persons infected with human immunodeficiency virus 1 (HIV-1) attenuated HIV replication as measured by plasma HIV RNA. We investigated systemic inflammation as measured by plasma levels of soluble tumor necrosis factor-alpha receptor II...... (sTNF-rII), interleukin-8, (IL-8), and IL-10 during schistosomiasis and HIV co-infection and after schistosomiasis treatment. The cohort was composed of 378 persons who were or were not infected with HIV-1, Schistosoma haematobium, or S. mansoni. Schistosomiasis-infected persons were randomized...... to receive praziquantel (40 mg/kg) at baseline or at the three-month follow-up. sTNF-rII and IL-8 were positively associated with schistosomiasis intensity as measured by circulating anodic antigen (CAA), regardless of HIV status. Interleukin-10 was positively associated with CAA in HIV-negative participants...
Olorunlana, Adetayo; Jegede, Ayodele Samuel; Morenikeji, Olajumoke; Hassan, Adesola A; Nwuba, Roseangela I; Anumudu, Chiaka I; Salawu, Oyetunde T; Odaibo, Alexander B
Transmission of schistosomiasis is aided by human behaviour. Globally, about 800 million people are at risk of schistosomiasis infection. Data exist on biomedical understanding of the disease transmission; there is a dearth of information from the social science perspective. Hence, this study explored the social and cultural context of schistosomiasis transmission among Yewa People in Nigeria. Qualitative methods were employed with purposive sampling, using the key informant interviews and focus group discussions, among 57 participants aged 17 to 54 years. The data were content-analyzed. River water was the most reported source of water supply among others. Participants drew from the cultural milieu the use of river water for "drinking" and "swimming" as part of the continual transmission of schistosomiasis. Transmission of schistosomiasis may not be abated without behavioural change.
Akinbo Frederick Olusegun
Full Text Available Objectives: This study aimed to determine the prevalence of urinary schistosomiasis, and the effect of CD4+ T cell counts and demographics on its prevalence among HIV-positive patients in Benin City, Nigeria.Methods: Urine and blood samples were collected from 2000 HIV-positive subjects. A wet preparation of the urine deposit was examined microscopically to identify ova of Schistosoma haematobium. The blood specimens were analyzed using the flow cytometry for CD4 + T-lymphocyte count.Results: An overall prevalence rate of 0.3% was reported. Gender and CD4 count <200 cells/µL did not affect the prevalence of urinary schistosomiasis, while HIV patients that were single had significantly higher prevalence of urinary schistosomiasis (p=0.002.Conclusion: The prevalence of urinary schistosomiasis among HIV patients in Benin City is low. CD4+ count did not affect the prevalence of urinary schistosomiasis.
To discuss the prevention of schistosomiasis in tourism of lake region. The seasonal distribution of tourism activities and spatial distribution of scenic spots, as well as the coupling between space and temporal of Oncomelania snail distribution and the transmission time of schistosomiasis in Poyang Lake region were analyzed. The travel preference of schistosomiasis susceptible population was surveyed by questionnaires and interviews. There were couplings of space and temporal between tourism activities in Poyang Lake region and transmission time of schistosomiasis as well as space distribution of snails, respectively. The most popular tourism items were Shuishangrenjia (overwater household) and fishing folk culture with property of participation and experience. The suggestion is to establish health records of tourists, carry out health education of schistosomiasis, and enhance the management of tourism and activities of tourists.
Full Text Available AbstrakSchistosomiasis merupakan salah satu penyakit parasit terpenting dalam kesehatan masyarakat. Di Indonesiaschistosomiasis disebabkan oleh cacing Schistosoma japonicum dengan hospes perantara keong Oncomelaniahupensis lindoensis. Penyakit ini hanya ditemukan di Provinsi Sulawesi Tengah di dua kabupaten yaitu Kabupaten Posodan Sigi. Selama ini pengendalian yang dilakukan masih bersifat rutin yaitu pengobatan, survei fokus keong,pengumpulan tinja, dan pengadaan tool kit. Belum pernah dilakukan penelitian dari aspek kebijakan pemerintah daerahdalam pengendalian schistosomiasis. Penelitian ini secara umum bertujuan untuk memberikan opsi kebijakan bagipemerintah daerah dalam pengendalian schistosomiasis. Tujuan khusus yang ingin dicapai adalah menilai persepsistakeholder mengenai pengendalian schistosomiasis, menilai kebijakan yang selama ini dilakukan oleh pemerintahdaerah dalam pengendalian schistosomiasis dan merumuskan suatu opsi kebijakan. Metode penelitian yang dipakaiadalah studi kualitatif dengan wawancara mendalam kepada stakeholder di Kabupaten Poso, Kabupaten Sigi, danpemerintah daerah Provinsi Sulawesi Tengah. Penentuan sampel dilakukan secara purposive sampling dimana sampeladalah stakeholder yang berkompeten mengeluarkan kebijakan tentang pengendalian schistosomiasis. Data primerdikumpulkan dengan wawancara mendalam, sedangkan data sekunder diperoleh dengan mengumpulkan dokumendokumenyang terkait dengan kebijakan pengendalian schistosomiasis. Hasil wawancara mendalam menunjukkanbahwa pada umumnya semua stakeholder sudah tahu kalau schistosomiasis adalah penyakit spesifik lokal yang diIndonesia cuma ada di Provinsi Sulawesi Tengah, apa penyebabnya dan bagaimana cara pengendaliannya. Tindaklanjut dari surat keputusan yang sudah dikeluarkan oleh Gubernur Sulawesi Tengah yang membentuk tim terpadupengendalian schistosomiasis sampai sekarang belum ada gerakan. Satuan Kerja Perangkat Daerah (SKPD yangdiharapkan terlibat, belum tahu apa
Jia-Sheng, Wang; Jin-You, Lu; Feng-Yang, Min; Kong-Xian, Zhu
The spread of schistosomiasis seriously threaten the health of people and hinder the economic and social development in China. The water conservancy combined with schistosomiasis prevention and control effectively controlled the spread of schistosomiasis by controlling the spread of Oncomelania hupensis , the only intermediate host of Schistosoma japonicum . This paper reviews the evolution of the strategy of schistosomiasis prevention and control in China and points out the historical role of water conservancy combined with schistosomiasis prevention and control. Furthermore, this article analyzes the problems and challenges of water conservancy combined with schistosomiasis prevention and control in the new period. In response to the challenges, the new strategy of water conservancy combined with schistosomiasis prevention and control is put forward, including: developing the research of the new strategy of water conservancy combined with schistosomiasis prevention and control, enhancing the research of water conservancy technology combined with schistosomiasis prevention and control, improving the efficiency and applicability of water conservancy projects combined with schistosomiasis prevention and control, strengthening the guidance of water conservancy technology combined with schistosomiasis prevention and control, and perfecting the evaluation system.
Rashika A.F. El Ridi
Full Text Available Schistosomiasis is a debilitating disease affecting approximately 600 million people in 74 developing countries, with 800 million, mostly children at risk. To circumvent the threat of having praziquantel (PZQ as the only drug used for treatment, several PZQ derivatives were synthesized, and drugs destined for other parasites were used with success. A plethora of plant-derived oils and extracts were found to effectively kill juvenile and adult schistosomes, yet none was progressed to pre- and clinical studies except an oleo-gum resin extracted from the stem of Commiphora molmol, myrrh, which action was challenged in several trials. We have proposed an essential fatty acid, a component of our diet and cells, the polyunsaturated fatty acid arachidonic acid (ARA as a remedy for schistosomiasis, due to its ability to activate the parasite tegument-bound neutral sphingomyelinase, with subsequent hydrolysis of the apical lipid bilayer sphingomyelin molecules, allowing access of specific antibody molecules, and eventual worm attrition. This concept was convincingly supported using larval and adult Schistosoma mansoni and Schistosoma haematobium worms in in vitro experiments, and in vivo studies in inbred mice and outbred hamsters. Even if ARA proves to be an entirely effective and safe therapy for schistosomiasis, it will not prevent reinfection, and accordingly, the need for developing an effective vaccine remains an urgent priority. Our studies have supported the status of S. mansoni calpain, glutathione-S-transferase, aldolase, triose phosphate isomerase, glyceraldehyde 3-phosphate dehydrogenase, enolase, and 2-cys peroxiredoxin as vaccine candidates, as they are larval excreted-secreted products and, contrary to the surface membrane molecules, are entirely accessible to the host immune system effector elements. We have proposed that the use of these molecules, in conjunction with Th2 cytokines-inducing adjuvants for recruiting and activating
Full Text Available Schistosomiasis is a chronic, debilitating parasitic disease infecting more than 200 million people and is second only to malaria in terms of public health importance. Due to the lack of a vaccine, patient therapy is heavily reliant on chemotherapy with praziquantel as the World Health Organization-recommended drug, but concerns over drug resistance encourage the search for new drug leads.The efficacy of the vinyl sulfone cysteine protease inhibitor K11777 was tested in the murine model of schistosomiasis mansoni. Disease parameters measured were worm and egg burdens, and organ pathology including hepato- and splenomegaly, presence of parasite egg-induced granulomas in the liver, and levels of circulating alanine aminotransferase activity as a marker of hepatocellular function. K11777 (25 mg/kg twice daily [BID], administered intraperitoneally at the time of parasite migration through the skin and lungs (days 1-14 postinfection [p.i.], resulted in parasitologic cure (elimination of parasite eggs in five of seven cases and a resolution of other disease parameters. K11777 (50 mg/kg BID, administered at the commencement of egg-laying by mature parasites (days 30-37 p.i., reduced worm and egg burdens, and ameliorated organ pathology. Using protease class-specific substrates and active-site labeling, one molecular target of K11777 was identified as the gut-associated cathepsin B1 cysteine protease, although other cysteine protease targets are not excluded. In rodents, dogs, and primates, K11777 is nonmutagenic with satisfactory safety and pharmacokinetic profiles.The significant reduction in parasite burden and pathology by this vinyl sulfone cysteine protease inhibitor validates schistosome cysteine proteases as drug targets and offers the potential of a new direction for chemotherapy of human schistosomiasis.
Luciana Santos Cardoso
Full Text Available The Th2 immune response in chronic schistosomiasis is associated with the development of periportal fibrosis. However, little is known about the phenotype and activation status of T cells in the process. Objective. To evaluate the profile of T cells in schistosomiasis patients with periportal fibrosis. Methods. It was a cross-sectional study, conducted in the village of Agua Preta, Bahia, Brazil, which included 37 subjects with periportal fibrosis determined by ultrasound. Peripheral blood mononuclear cells were obtained by the Ficcol-hypaque gradient and the frequency of T cells expressing the surface markers CD28, CD69, CD25, and CTLA-4 was determined by flow cytometry. Results. The frequency of CD4+CD28+ T lymphocytes was higher in individuals with moderate to severe fibrosis compared to patients with incipient fibrosis. We did not observe any significant difference in the frequency of CD4+ T cells expressing CD69 among groups of individuals. There was also no significant difference in the frequency of CD8+ T cells expressing CD28 or CD69 among the studied groups. Individuals with moderate to severe fibrosis presented a lower frequency of CD8+ T cells, CD4+CD25high T cells, and CD4+CTLA-4+ T cells when compared to patients without fibrosis or incipient fibrosis. The frequency of CD4+CD25low cells did not differ between groups. Conclusion. The high frequency of activated T cells coinciding with a low frequency of putative Treg cells may account for the development of periportal fibrosis in human schistosomiasis.
Juçara C. Parra
Full Text Available Infection with Schistosoma mansoni induces humoral and T cell mediated responses and leads to delayed hipersensitivity that results in granulomatous inflamatory disease around the parasite eggs. Regulation of these responses resulting in a reduction in this anti-egg inflamatory disease is appsrently determined by idiotypic repertoires of the patient, associated with genetic background and multiple external factors. We have previously reported on idiotype/anti-idiotype-receptor transactions in clinical human schistosomiasis. These findings support a hypothesis that anti-SEA cross-reactive idiotypes develop in some patients during the course of a chronic infection and participate in regulation of anti-SEA cellular immune responses. We repport here on experiments wich extend those observations to the regulation of granulomatous hypersensitivity measured by an in vitro granuloma model. T cells from chronic intestinal schistosomiasis patients were stimulated in vitro with anti-SEA idiotypes and assayed in an autologous in vitro granuloma assay for modulation of granuloma formation. These anti-SEA idiotype reactive T cells were capable of regulating autologous in vitro granuloma formation. This regulatory activity, initiated with stimulatory anti-SEA idiotypic antibodies, was antigenically specific and was dependent on the present of intact (F(ab'2 immunoglobulin molecules. The ability to elicit this regulatory activity appears to be dose dependent and is more easily demonstrated in chronically infected intestinal patients or SEA sensitized individuals. These data support the hypothesis that anti-SEA cross reactive idiotypes are important in regulating granulomatous hypersensitivy in chronic intestinal schistosomiasis patients and these cross-reactive idiotypes appear to play a major role in cell-cell interactions which result in the regulation of anti-SEA cellular immune responses.
José Rodrigues Coura
Full Text Available The great hope for schistosomiasis treatment began with the development of oxamniquine and praziquantel. These drugs can be administered orally in a single dose and have a high curative power with minor side effects. In this study, we carried out a field experiment involving a population of 3,782 people. The population was examined at four localities in Minas Gerais within the valleys of the Doce and Jequitinhonha Rivers. In this cohort, there were 1,790 patients infected with Schistosoma mansoni (47.3% and we showed that only 1,403 (78.4% could be treated with oxamniquine in a single dose of 12.5-20 mg/kg orally. The other 387 (21.6% were not treated during the first stage because of contraindications (pregnancy or impeditive diseases, absences or refusals. It was observed that, on average, 8.8-17% of the infected patients continued to excrete S. mansoni eggs at the end of the 2nd month after treatment and 30-32% of the cohort was infected by the end of the 24th month. In one of the areas that we followed-up for a total of 30 years, the prevalence of the infection with S. mansoni fell from 60.8-19.3% and the hepatosplenic form of the disease dropped from 5.8-1.3%. We conclude that specific treatment of schistosomiasis reduces the prevalence of infection in the short-term and the morbidity due to schistosomiasis in medium to long-term time frames, but does not help to control disease transmission.
Islam, M. N.; Begum, N; Alam, M. Z.; M.A.A. Mamun
We assessed the prevalence and seasonal variations of intestinal schistosomiasis in association with age, sex, breed and rearing system of cattle and goats in different districts of Bangladesh. Fecal samples from 240 cattle and 146 goats were examined. Schistosoma eggs were found in 47.5% cattle and 43.84% goats. Two species of schistosomes were identified. No mixed infection was recorded. Prevalence of Schistosoma indicum was higher in cattle (42.5%) than in goats (34.25%) whereas goats (9.5...
Full Text Available Abstract Background Contrary to previous reports which indicated no transmission of schistosomiasis at altitude >1,400 m above sea level in Uganda, in this study it has been established that schistosomiasis transmission can take place at an altitude range of 1487–1682 m above sea level in western Uganda. Methods An epidemiological survey of intestinal schistosomiasis was carried out in school children staying around 13 high altitude crater lakes in Western Uganda. Stool samples were collected and then processed with the Kato-Katz technique using 42 mg templates. Thereafter schistosome eggs were counted under a microscope and eggs per gram (epg of stool calculated. A semi-structured questionnaire was used to obtain demographic data and information on risk factors. Results 36.7% of the pupils studied used crater lakes as the main source of domestic water and the crater lakes studied were at altitude ranging from 1487–1682 m above sea level. 84.6% of the crater lakes studied were infective with over 50% of the users infected. The overall prevalence of Schistosoma mansoni infection was 27.8% (103/370 with stool egg load ranging from 24–6048 per gram of stool. 84.3%( 312 had light infections (400 egg/gm of stool. Prevalence was highest in the age group 12–14 years (49.5% and geometric mean intensity was highest in the age group 9–11 years (238 epg. The prevalence and geometric mean intensity of infection among girls was lower (26%; 290 epg compared to that of boys (29.6%; 463 epg (t = 4.383, p Conclusion and recommendations The altitudinal threshold for S. mansoni transmission in Uganda has changed and use of crater water at an altitude higher than 1,400 m above sea level poses a risk of acquiring S. mansoni infection in western Uganda. However, further research is required to establish whether the observed altitudinal threshold change is as a result of climate change or other factors. It is also necessary to establish the impact this could
van Dijk, Karin; Starink, Markus V.; Bart, Aldert; Nijhuis, Erik W. P.; van der Wal, Allard C.; van Thiel, Pieter P. A. M.; de Vries, Henry J. C.; van Gool, Tom
A 28-year-old woman presented with extensive erythematous lesions on her back after visiting Malawi. Skin biopsies showed ova, which could belong to Schistosoma spp. Sequencing of the Schistosoma 28S rRNA gene, extracted and amplified from paraffin biopsies, identified DNA of Schistosoma haematobium. Cutaneous ectopic schistosomiasis can present with extensive lesions and should be considered in the differential diagnosis of skin lesions in returning travelers. Microscopy and serology are the classical methods to obtain a diagnosis. Alternatively, molecular methods can be a valuable new tool for diagnosis and species determination. PMID:20889899
Justin Komguep Nono
Full Text Available Interleukin-4 receptor (IL-4Rα is critical for the initiation of type-2 immune responses and implicated in the pathogenesis of experimental schistosomiasis. IL-4Rα mediated type-2 responses are critical for the control of pathology during acute schistosomiasis. However, type-2 responses tightly associate with fibrogranulomatous inflammation that drives host pathology during chronic schistosomiasis. To address such controversy on the role of IL-4Rα, we generated a novel inducible IL-4Rα-deficient mouse model that allows for temporal knockdown of il-4rα gene after oral administration of Tamoxifen. Interrupting IL-4Rα mediated signaling during the acute phase impaired the development of protective type-2 immune responses, leading to rapid weight loss and premature death, confirming a protective role of IL-4Rα during acute schistosomiasis. Conversely, IL-4Rα removal at the chronic phase of schistosomiasis ameliorated the pathological fibro-granulomatous pathology and reversed liver scarification without affecting the host fitness. This amelioration of the morbidity was accompanied by a reduced Th2 response and increased frequencies of FoxP3+ Tregs and CD1dhiCD5+ Bregs. Collectively, these data demonstrate that IL-4Rα mediated signaling has two opposing functions during experimental schistosomiasis depending on the stage of advancement of the disease and indicate that interrupting IL-4Rα mediated signaling is a viable therapeutic strategy to ameliorate liver fibroproliferative pathology in diseases like chronic schistosomiasis.
Xiong, Jiang-Qin; Xiong, Ping-Xiang; Ning, An; Xu, Li-Ping; Hu, Mei-Ying; Yang, De-Ping; Zu, Jing; Ai, You-Sheng; Zou, Jie-Xin; Zhou, Xian-Min; Xiong, Xiao-Liang; Yang, Min
To understand the gastroscopic and pathological characteristics of patients with miasis in Poyang Lake area, and to explore the relationship between schistosomiasis and pathological changes of gastric mucosa. Volunteers with or without schistosomiasis were recruited and divided into a case group and a control group. All the objects were examined by electronic gastroscopy and pathological examinations. Two hundred and fifty-three volunteers diagnosed with chronic or advanced schistosomiasis in the case group showed different degrees of gastric mucosal changes, including 7 cases with schistosomal eggs deposited beneath the gastric mucosa (with an incidence of 2.77%) , 33 cases with dysplastic hyperplasia and intestinal metaplasia (with an incidence of precancerous lesion of 13.04%), and 1 case with gastric cancer. While in the 200 volunteers without schistosomiasis in the control group, the results showed milder gastric mucosal changes, 33 cases were detected with dysplastic hyperplasia and intestinal metaplasia (with an incidence of 7.50%), and 1 case was diagnosed gastric cancer. The difference between the incidences of precancerous lesion in the two groups had no statistic significance (P > 0.05). The incidence and extent of gastric mucosal changes in schistosomiasis patients are higher and more serious than those in non-schistosomiasis patients, and gastrointestinal schistosomiasis is not related to gastric cancer.
Rassi, Christian; Kajungu, Dan; Martin, Sandrine; Arroz, Jorge; Tallant, Jamie; Zegers de Beyl, Celine; Counihan, Helen; Newell, James N; Phillips, Anna; Whitton, Jane; Muloliwa, Artur Manuel; Graham, Kirstie
Schistosomiasis is a parasitic disease which affects almost 300 million people worldwide each year. It is highly endemic in Mozambique. Prevention and control of schistosomiasis relies mainly on mass drug administration (MDA), as well as adoption of basic sanitation practices. Individual and community perceptions of schistosomiasis are likely to have a significant effect on prevention and control efforts. In order to establish a baseline to evaluate a community engagement intervention with a focus on schistosomiasis, a survey to determine knowledge, attitudes and practices relating to the disease was conducted. A representative cross-sectional household survey was carried out in four districts of Nampula province, Mozambique. Interviews were conducted in a total of 791 households, using a structured questionnaire. While awareness of schistosomiasis was high (91%), correct knowledge of how it is acquired (18%), transmitted (26%) and prevented (13%) was low among those who had heard of the disease. Misconceptions, such as the belief that schistosomiasis is transmitted through sexual contact (27%), were common. Only about a third of those who were aware of the disease stated that they practiced a protective behaviour and only a minority of those (39%) reported an effective behaviour. Despite several rounds of MDA for schistosomiasis in the recent past, only a small minority of households with children reported that at least one of them had received a drug to treat the disease (9%). Poor knowledge of the causes of schistosomiasis and how to prevent it, coupled with persisting misconceptions, continue to pose barriers to effective disease prevention and control. To achieve high levels of uptake of MDA and adoption of protective behaviours, it will be essential to engage individuals and communities, improving their understanding of the causes and symptoms of schistosomiasis, recommended prevention mechanisms and the rationale behind MDA.
Full Text Available This case report refers to a 47-year old patient with prostate cancer associated with schistosomiasis mansoni, who was submitted to radical prostatectomy. This is the third report published in the literature with respect to this association, and up to the present time it is still not known whether a cause and effect relationship exists between the two pathologies. The association between schistosomiasis and cancer has been well-documented in bladder cancer; however, there are no data yet proving the association of this disease with prostatic neoplasia. In this report, a third documented case of prostatic adenocarcinoma and schistosomiasis mansoni is described and a literature review is performed.
Genilde Gomes de Oliveira
Full Text Available Introduction Schistosomiasis is endemic in 74 countries and is considered a serious public health problem in some locations. Methods A transverse study was performed of 13 landless settlements in southern Sergipe from February to December 2009. The study included 822 settlers, of whom 601 underwent stool testing. Results The prevalence of schistosomiasis in landless workers was 4.3%. The population has a low education level, and basic sanitation services are not available to all residents. Conclusions The prevalence of schistosomiasis was low in the population and among different settlements, possibly because of different forms of water use by the settlers.
Luo, Zhi-Hong; Li, Sheng-Ming; Zhou, Xiao-Nong; Yi, Ping; Ren, Guang-Hui; Franziska, Bieri; Zhao, Zheng-Yuan; Hou, Xun-Ya; Ren, Mao-Yuan; Li, Yi-Yi; Dong, Ru-Lan; Zeng, Jin-Yuan; She, Shu-Ping
To clarify the role of socio-economy and management in the sustainable schistosomiasis-control in Taoyuan County, an endemic area in hilly region, Hunan Province, China. From 1996 to 2011, the data of socio-economy, the management of schistosomiasis control organizations, environment, and the changes in schistosomiasis prevalence were collected in Taoyuan County where schistosomiasis transmission had been controlled since 2008. A sampling survey of schistosomiasis prevalence of human and bovine was performed in 2011 to verify the current status of schistosomiasis transmission. All the data were analyzed statistically to evaluate the role of socio-economy and management in the sustainable schistosomiasis control. During the period from 1998 to 2012, the socio-economy including the residents' productive mode and daily life in Taoyuan County improved dramatically, but the recurrence risk of schistosomiasis endemic still existed due to the retuning of out-going workers and the migrating population. Moreover, the introduction of exotic species of plants and animals may increase the risk. The low running cost of schistosomiasis control organization as well as the efficient and adequate resource allocation in the county was in line with the national requirement to strengthen the rural grass-roots public health system. The harmonious development of socio-economy and the scientific and efficient health system in Taoyuan County are the key factors for the sustainable transmission control of schistosomiasis.
Blas, Bayani L; Rosales, Manuel I; Lipayon, Ignacio L; Yasuraoka, Kazuo; Matsuda, Hajime; Hayashi, Masataka
A descriptive study was carried on the schistosomiasis problem in the Philippines from the time the disease was discovered in 1906 to the latter part of the 1990 s. Some research findings were reviewed including the nature of the disease itself. Based on the thrust of the control program which is centered mainly on selective mass treatment and progressed to disease stratification and mass treatment using praziquantel, a downward trend in the prevalence of the disease was observed-from an average of 10.4% in 1981-1985 to 4.1% in 1996. Recommended prospective action, among others, include the development of strategies on environmental sanitation and snail control/eradication in the thrust of the schistosomiasis control program. Other policy related concerns should be formulated subject to the results of further research activities such as on (a) chemotherapy; (b) drug delivery schemes; (c) diagnosis; (d) search for a safe, economical and effective chemical(s) for vector control; and (e) prophylaxis and vaccine production for protection against infection for disease modulation or reduction of pathology.
Favero, Vivian; Frasca Candido, Renata Russo; De Marco Verissimo, Carolina; Jones, Malcolm K; St Pierre, Timothy G; Lindholz, Catieli Gobetti; Da Silva, Vinicius Duval; Morassutti, Alessandra Loureiro; Graeff-Teixeira, Carlos
A diagnostic test that is reliable, sensitive, and applicable in the field is extremely important in epidemiological surveys, during medical treatment for schistosomiasis, and for the control and elimination of schistosomiasis. The Helmintex (HTX) method is based on the use of magnetic beads to trap eggs in a magnetic field. This technique is highly sensitive, but the screening of fecal samples consumes lots of time, thus delaying the results, especially in field studies. The objective of this work was to determine the effects of incorporation of the detergent Tween-20 into the method in an attempt to decrease the final pellet volume produced by the HTX method as well as the use of ninhydrin to stain the Schistosoma mansoni eggs. We showed that these modifications reduced the final volume of the fecal sediment produced in the last step of the HTX method by up to 69% and decreased the screening time to an average of 10.1 min per sample. The use of Tween 20 and ninhydrin led to a high percentage of egg recovery (27.2%). The data obtained herein demonstrate that the addition of detergent and the use of ninhydrin to the HTX process can optimize the screening step and also improve egg recovery, thus justifying the insertion of these steps into the HTX method. Copyright © 2017 Elsevier Inc. All rights reserved.
Tomiotto-Pellissier, Fernanda; Miranda-Sapla, Milena Menegazzo; Machado, Laís Fernanda; Bortoleti, Bruna Taciane da Silva; Sahd, Claudia Stoeglehner; Chagas, Alan Ferreira; Assolini, João Paulo; Oliveira, Francisco José de Abreu; Pavanelli, Wander Rogério; Conchon-Costa, Ivete; Costa, Idessania Nazareth; Melanda, Francine Nesello
Schistosomiasis is a neglected disease that affects millions of people worldwide, recognized as the most important human helminth infection in terms of morbidity and mortality. The treatment of choice presents low bioavailability and water solubility, in addition to the induction of parasite resistance. In this context, researchers have been conducting studies seeking to develop new drugs to ensure safety, quality, and efficacy against this parasitosis. In this scenario, nanotechnology arises including the drug delivery systems in nanoscale: nanoemulsions, liposomes and nanoparticles. These drug delivery systems have been extensively applied for in vitro and in vivo studies against Schistosoma spp. with promising results. This review pointed out the most relevant development scenarios regarding the treatment of schistosomiasis as well as the application of nanotechnology as a vaccine, highlighting the use of nanotechnology as an alternative therapy for both the repositioning of drugs and the use of new pharmaceutical products, with promising results regarding the aforementioned disease. Copyright © 2017 Elsevier B.V. All rights reserved.
Ricardo J. P. S. Guimarães
Full Text Available Geographic Information Systems (GISs are composed of useful tools to map and to model the spatial distribution of events that have geographic importance as schistosomiasis. This paper is a review of the use the indicator kriging, implemented on the Georeferenced Information Processing System (SPRING to make inferences about the prevalence of schistosomiasis and the presence of the species of Biomphalaria, intermediate hosts of Schistosoma mansoni, in areas without this information, in the Minas Gerais State, Brazil. The results were two maps. The first one was a map of Biomphalaria species, and the second was a new map of estimated prevalence of schistosomiasis. The obtained results showed that the indicator kriging can be used to better allocate resources for study and control of schistosomiasis in areas with transmission or the possibility of disease transmission.
Tang, Hong-Ping; Huang, Yong-Jun; She, Guang-son; Xie, Yang; Gao, Yang
To evaluate the effect of comprehensive measures on the control of schistosomiasis in an aquaculture zone, so as to provide the evidence for formulating the schistosomiasis control strategy in special environments. From 2003 to 2012, the comprehensive control measures including individual prevention, detection and treatment of schistosomiasis patients, environmental modification, and health education were implemented in an aquaculture zone of Luyang Lake, Jiangdu District of Yangzhou City, Jiangsu Province. The changes in human morbidity of schistosomiasis and the status of Oncomelania snails were investigated annually. No acute infection of Schistosoma japonicum was detected for successive 10 years, and only 5 cases of chronic infection were found in the latest 5 years in the aquaculture zone. Since 2007, no snail habitats were found. The comprehensive control measures are effective.
Full Text Available Beberapa penyakit parasitik pada manusia yang disebabkan oleh cacing trematoda seperti schistomiasis, echinostomiasis, paragonimiasis, dan sebagai hospes perantara adalah oleh beberapa anggota famili keong air tawar. Schistosomiasis merupakan penyakit parasitik yang endemis di Indonesia, khususnya di Dataran Tinggi Napu, Lindu dan Bada, Sulawesi Tengah. Informasi mengenai genus keong yang ditemukan di daerah fokus keong perantara schistosomiasis diperlukan dalam menentukan potensi terjadinya penularan penyakit akibat cacing trematoda yang lain. Survei dilakukan di dalam kawasan Taman Nasional Lore Lindu, Sulawesi Tengah pada Bulan Juli 2013. Identifikasi keong dilakukan menggunakan kunci determinasi keong air tawar di Laboratorium Parasitologi, Balai Litbang P2B2 Donggala. Jenis keong yang ditemukan meliputi Oncomelania hupensis lindoensis, Melanoides sp., Helicorbis sp., Indoplanorbis sp. yang merupakan hospes perantara trematoda parasit. Berdasarkan hasil tersebut dapat dilihat bahwa selain berpotensi dalam penularan schistosomiasis daerah tersebut juga berpotensi untuk terjadinya penularan penyakit akibat cacing trematoda lain, seperti Echinostomiasis dan Paragonimiasis. Kata kunci: variasi, keong, schistosomiasis
Xu, J; Bergquist, R; Qian, Y-J; Wang, Q; Yu, Q; Peeling, R; Croft, S; Guo, J-G; Zhou, X-N
Schistosomiasis, a disease caused by a trematode, parasitic worm, is a worldwide public health problem. In spite of great progress with regard to morbidity control, even elimination of this infection in recent decades, there are still challenges to overcome in sub-Saharan Africa and endemic areas in Southeast Asia. Regarded as one of the most successful countries with respect to schistosomiasis control, The People's Republic of China has accumulated considerable experience and learnt important lessons in various local settings that could benefit schistosomiasis control in other endemic countries. Based on an analysis of conceived strengths, weaknesses, opportunities and threats (SWOT) of potential collaborative activities with regard to schistosomiasis in Africa and Asia, this article addresses the importance of collaborative efforts and explores the priorities that would be expected to facilitate the transfer of Chinese experience to low- and middle-income countries in Africa and Asia. Copyright © 2016 Elsevier Ltd. All rights reserved.
Kamel, Mahmoud Hamdy
The authors report on a case of schistosomiasis of the spinal cord in an individual returning to Ireland after a 25-year residence in Africa, where the infection affects approximately 200 million people.
Ndassa, A; Mimpfoundi, R; Gake, B; Paul Martin, M V; Poste, B
The Upper Benue valley is inhabited by human populations of mixed background and socio-economic status. The area is an old and intense focus of both urinary schistosomiasis (caused by Schistosoma haematobium) and intestinal schistosomiasis (caused by S. mansoni). Most of the local villages have stand-pipes that provide clean drinking water but bathing, laundry, dishwashing and swimming are largely confined to nearby, snail-infested rivers, streams, irrigation canals and pools. The results of interviews and a multivariate analysis indicated that, in this region of Cameroon, a subject's age, knowledge of schistosomiasis, ethnic group and intensity of water contact (with rivers, streams and pools) were all significantly associated with schistosome infection. Curiously, a high level of knowledge about schistosomiasis was positively associated with infection.
Wen-di, Zhou; Liang, Shi; Xue-Dan, Ke; Jie, Wang
To summarize the present development by analysis of projects in schistosomiasis funded by National Science Foundation of China (NSFC). Based on the ISIS database of NFSC, the projects in the studies of schistosomiasis from 2005 to 2016 were analyzed. The distributions of sponsored numbers, amounts, types, agencies, disciplines and changes in research topics by means of network profiles were described. During the study period, 198 projects were funded by NSFC totally with 76.05 million yuan in which the general and youth projects were main types. The main sponsored agencies were research institutes and medical colleges. The top three fields sponsored were medical pathogenic microbes and infection, veterinary and medical immunology. The funding on schistosomiasis researches has a downward trend, but studies are continuing in depth. In this situation, innovative and interdisciplinary researches need to be encouraged to promote the development of schistosomiasis.
Cardim, Luciana Lobato; Ferraudo, Antonio Sergio; Pacheco, Selma Turrioni Azevedo; Reis, Renato Barbosa; Silva, Marta Mariana Nascimento; Carneiro, Deborah Daniela M Trabuco; Bavia, Maria Emilia
The spread of schistosomiasis mansoni defies efforts by Brazil's Unified National Health System, thus demonstrating the need to reassess endemic control programs in the country. The aim of this study was to demarcate geographic areas at risk of schistosomiasis in Lauro de Freitas, Bahia State, Brazil, and to establish the epidemiological and socioeconomic profile of the disease in this municipality (county). Kernel density estimator exploratory analysis was used for visual identification of areas at risk. Kulldorff & Nagarwalla's spatial analysis was used to obtain statistically significant clusters and to measure risk. These technologies identified four risk areas for schistosomiasis. Clusters identified within the risk areas were characterized by lower socioeconomic conditions. Multiple correspondence analyses showed a distinct profile for positive patients in the primary cluster. The techniques employed here represent an important methodological acquisition for tracking and controlling schistosomiasis in Lauro de Freitas.
Sulahian, Annie; Garin, Yves Jean François; Izri, Arezki; Verret, Caroline; Delaunay, Pascal; van Gool, Tom; Derouin, Francis
We evaluated the performance of Western blot (WB) analysis using commercially available antigen strips and compared the results with those of indirect hemagglutination (IHA) and indirect immunofluorescence (IFAT) for the serodiagnosis of human schistosomiasis. The antigen preparation was a crude
Kommu Sudhakar; Sreenivasa Murthy, G. S.; Gaddam Rajeshwari
Aim: Bovine visceral schistosomiasis has been reported as an important disease entity as it affects animal health, productivity, causes economic losses due to liver condemnation, and produces a high morbidity. This study was conducted to standardize an easy, reliable dot-enzyme-linked immmunosorbent assay (ELISA) for the diagnosis of visceral schistosomiasis caused by Schistosoma spindale and to know the prevalence rate in and around Hyderabad. Materials and Methods: A dot-ELISA was stand...
Wang, Ying; Lu, Zhouqin; Tian, Lihong; Tan, Li; Shi, Yun; Nie, Shaofa; Liu, Li
Backgrounds/Objective Schistosomiasis is still a major public health problem in China, despite the fact that the government has implemented a series of strategies to prevent and control the spread of the parasitic disease. Advanced warning and reliable forecasting can help policymakers to adjust and implement strategies more effectively, which will lead to the control and elimination of schistosomiasis. Our aim is to explore the application of a hybrid forecasting model to track the trends of the prevalence of schistosomiasis in humans, which provides a methodological basis for predicting and detecting schistosomiasis infection in endemic areas. Methods A hybrid approach combining the autoregressive integrated moving average (ARIMA) model and the nonlinear autoregressive neural network (NARNN) model to forecast the prevalence of schistosomiasis in the future four years. Forecasting performance was compared between the hybrid ARIMA-NARNN model, and the single ARIMA or the single NARNN model. Results The modelling mean square error (MSE), mean absolute error (MAE) and mean absolute percentage error (MAPE) of the ARIMA-NARNN model was 0.1869×10−4, 0.0029, 0.0419 with a corresponding testing error of 0.9375×10−4, 0.0081, 0.9064, respectively. These error values generated with the hybrid model were all lower than those obtained from the single ARIMA or NARNN model. The forecasting values were 0.75%, 0.80%, 0.76% and 0.77% in the future four years, which demonstrated a no-downward trend. Conclusion The hybrid model has high quality prediction accuracy in the prevalence of schistosomiasis, which provides a methodological basis for future schistosomiasis monitoring and control strategies in the study area. It is worth attempting to utilize the hybrid detection scheme in other schistosomiasis-endemic areas including other infectious diseases. PMID:25119882
Nalugwa, A.; Olsen, Annette; Tukahebwa, M. E.
prevalence and intensity of infection were examined in 3058 children from 5 districts along Lake Victoria shoreline, eastern Uganda. For each child one stool sample was collected on three consecutive days. The Kato-Katz technique was used to prepare stool smears on slides for microscopic examination. Short...... for schistosomiasis takes preschool children into consideration and that health education on transmission of schistosomiasis is delivered to the endemic communities regularly....
Full Text Available Schistosomiasis, one of the most prevalent neglected tropical diseases, is a life-threatening public health problem in Yemen especially in rural communities. This cross-sectional study aims to determine the prevalence and associated risk factors of schistosomiasis among children in rural Yemen.Urine and faecal samples were collected from 400 children. Urine samples were examined using filtration technique for the presence of Schistosoma haematobium eggs while faecal samples were examined using formalin-ether concentration and Kato Katz techniques for the presence of S. mansoni. Demographic, socioeconomic and environmental information were collected via a validated questionnaire. Overall, 31.8% of the participants were found to be positive for schistosomiasis; 23.8% were infected with S. haematobium and 9.3% were infected with S. mansoni. Moreover, 39.5% of the participants were anaemic whereas 9.5% had hepatosplenomegaly. The prevalence of schistosomiasis was significantly higher among children aged >10 years compared to those aged ≤ 10 years (P<0.05. Multivariate analysis confirmed that presence of other infected family member (P<0.001, low household monthly income (P = 0.003, using unsafe sources for drinking water (P = 0.003, living nearby stream/spring (P = 0.006 and living nearby pool/pond (P = 0.002 were the key factors significantly associated with schistosomiasis among these children.This study reveals that schistosomiasis is still highly prevalent in Yemen. These findings support an urgent need to start an integrated, targeted and effective schistosomiasis control programme with a mission to move towards the elimination phase. Besides periodic drug distribution, health education and community mobilisation, provision of clean and safe drinking water, introduction of proper sanitation are imperative among these communities in order to curtail the transmission and morbidity caused by schistosomiasis. Screening and treating other infected
Zhang, Hui-juan; Guo, Jia-gang
Possible impact of ecological and social environmental changes due to the construction of the Three Gorges Dam on the transmission of schistosomiasis draws great attention of the health authority and publics. This article reviews the situation and progress of research on schistosomiasis transmission in reservoir area from three aspects: the possibility of snail spreading and breeding, imported infection sources and social behavioral factors of the people.
Tanabe, M; Okazaki, M; Okazaki, M; Kobayashi, S; Kaneko, N; Sekiguchi, T; Tateno, S; Motta, S R; Takeuchi, T
Sera from the patients (N = 10) with schistosomiasis mansoni of the hospital of Federal University of Pernambuco, the Schistosoma mansoni egg-positive (N = 51) and -negative (N = 452) inhabitants in Cabo City area, out-patients (N = 37) of the IMIP hospital and Japanese immigrants (N = 127) in Petrolina City area of northeast Brazil as well as Japanese healthy subjects (N = 30) were examined by serological tests including an enzyme-linked immunosorbent assay with antigens prepared from eggs (ELISA-egg) and adult worms (ELISA-adult). The ELISA with egg or adult antigen correctly identified 100% of the uninfected individuals lived in non-endemic area of schistosomiasis. Moreover, when examined cross-reactivity of our ELISA with sera isolated from 78 subjects infected with various intestinal parasitic infections, only one of these sera reacted with the egg and adult antigens. On the examination of 51 sera from the egg-positive subjects, the ELISA-egg revealed the highest sensitivity (98.0%), whereas a large number of false negative reactions of ELISA-adult, Ouchterlony method using adult antigen, circumoval precipitation and immediate intradermal skin test were observed. A low sensitivity of these serologic tests except for ELISA-egg appears to be primarily due to their inability to detect antibody in the sera from egg-positive infantiles. There was no positive correlation between the absorbance values of these two types of ELISA among the sera isolated from ELISA-positive subjects. Rather, by the reactivity of these sera to egg or adult antigen, they could be divided into two subgroups; one reacted more positively with egg antigen and the other with adult antigen. Moreover, it was confirmed that the sera from young subjects (under 20 years old) appear to be highly reactive to the egg antigen than did aged ones. These data suggest that the ELISA with egg antigen, but not with the adult antigen, appears to be useful for the serological survey of schistosomiasis mansoni
Zong-Liang, Feng; Sha-Sha, Li; Jiao, Hua; Lin, Chen; Zi-Song, Wu; Cong-Min, Xu; Yu-Hua, Lai
To evaluate the intervention effect of Yi-Han bilingual health education of schistosomiasis control. Baimiao Village in Daqing Town, Xichang City, where Yi Nationality inhabited, was chosen as a pilot to carry out Yi-Han bilingual health education of schistosomiasis control from 2012 to 2015. The villagers and students in the pilot area were investigated by questionnaires before and after the intervention to understand their awareness and correct behavior status on schistosomiasis control. After the intervention of Yi-Han bilingual health education of schistosomiasis control for 3 years, the awareness rate and the correct rate of behavior on schistosomiasis control of the villagers in the pilot area improved from 45.79% and 51.12% in 2012 to 97.80% and 98.78% in 2015. As for the students, the two rates mentioned above improved from 64.16% and 60.83% in 2012 to 100% and 98.89% in 2015 respectively, and all the differences between the rates before and after the intervention were statistically significant (all P bilingual health education of schistosomiasis control can obviously improve the knowledge awareness rates and the correct rates of behavior of the residents and students in the gathering area of Yi Nationality.
Zhang, Ke; Liu, Ning; Hou, Kai; Hou, Ning; Gong, Yun-hua; Zhang, Qiu-ping; Ye, Jia-ming; Wang, Biao; Sun, Ji-ji
To evaluate the effectiveness of integrated schistosomiasis control strategy in marshlands of Qixia District from 2004 to 2013. The endemic situation and integrated control data of schistosomiasis in Qixia District from 2004 to 2013 were collected, and the morbidity and Oncomelania hupensis snail status before and after the implementa- tion of integrated schistosomiasis control strategy were compared. Following 10-year integrated schistosomiasis control, the human schistosome infection rate gradually decreased in Qixia District, and no infection was detected since 2007. A gradual reduction was observed in the infection rate of domestic animals, and all bovine was eliminated from the regions along the Yangtze River since 2006. In addition, the snail area and the density of living snails in 2013 reduced by 42.25% and 82.56% as compared to those in 2004, and no infected snails were found since 2009. In 2010, the district achieved schistoso- miasis transmission control. The integrated schistosomiasis control strategy is effective to accelerate schistoso- miasis control process and achieve the criteria of schistosomiasis transmission control rapidly.
Li, Zhongwu; Nie, Xiaodong; Zhang, Yan; Huang, Jinquan; Huang, Bin; Zeng, Guangming
Schistosomiasis is a severe public health problem in the Dongting Lake region, and its distribution, prevalence, and intensity of infection are particularly sensitive to environmental changes. In this study, the human and bovine schistosomiasis variations in the Dongting Lake region were studied from 1996 to 2010, and the relationships between schistosomiasis and water level were examined. Furthermore, based on these results, the potential effects of the Three Gorges Dam (TGD) on schistosomiasis were investigated. Results showed an increase in human schistosomiasis and in the scope of seriously affected regions, along with a decrease in bovine schistosomiasis. Human schistosomiasis was negatively correlated with water level during wet season (from May to October), particularly the average water level in October. This finding indicated that the decreasing water level may be highly related to the increasing of human schistosomiasis in the Dongting Lake region. Based on this result and the variation of schistosomiasis before and after the construction and operation of TGD, the impoundment of the Three Gorges reservoir is believed to decrease the water level and increase the contact between people and schistosomiasis. Therefore, the TGD, which is operated by regulating water and scheduling water operations, is not good for the control of human schistosomiasis in the Dongting Lake region. Although the extent of the influence of the TGD on schistosomiasis remains unclear, the influence of the TGD on preventing and controlling schistosomiasis should not be ignored.
Imadeldin Elamin Aradaib
Full Text Available Six calves were immunized with schistosomula of Schistosoma bovis irradiated at 3 or 20 Kilorad (Krad and three calves were kept as controls. Twenty four weeks post immunization, three calves (one from the 20 Krad and two from the 3 Krad group were challenged with normal cercaria of S. bovis. The immune response was monitored by agar gel immunodiffusion (AGID and the Enzyme Linked Immunosorbent Assay (ELISA using adult worm antigen. Using AGID, precipitin lines were observed only with sera from challenged animals. Using ELISA, the immune response of the vaccinated calves was first detected by 2-3 weeks, peaking by 6-8 weeks post vaccination. The immune response of the three challenged calves was elevated by 2 weeks post challenge, peaking at 8-10 weeks post challenge and remained high throughout the experimental period. This study suggests that ELISA could be used for diagnosis of bovine schistosomiasis.
Paula Carolina Valenca Silva
Full Text Available Introduction This study evaluates the factors associated with the development of severe periportal fibrosis in patients with Schistosoma mansoni. Methods A cross-sectional study was conducted from April to December 2012 involving 178 patients infected with S. mansoni who were treated in the Hospital das Clínicas of Pernambuco, Brazil. Information regarding risk factors was obtained using a questionnaire. Based on the patients' epidemiological history, clinical examination, and upper abdomen ultrasound evaluation, patients were divided into 2 groups: 137 with evidence of severe periportal fibrosis and 41 patients without fibrosis or with mild or moderate periportal fibrosis. Univariate and multivariate analyses were conducted using EpiInfo software version 3.5.5. Results Illiterate individuals (30.1% and patients who had more frequent contact with contaminated water in towns in the Zona da Mata of Pernambuco (33.2% were at greater risk for severe periportal fibrosis. Based on multivariate analysis, it was determined that an education level of up to 11 years of study and specific prior treatment for schistosomiasis were preventive factors for severe periportal fibrosis. Conclusions The prevailing sites of the severe forms of periportal fibrosis are still within the Zona da Mata of Pernambuco, although there has been an expansion to urban areas and the state coast. Specific treatment and an increased level of education were identified as protective factors, indicating the need for implementing social, sanitary, and health education interventions aimed at schistosomiasis to combat the risk factors for this major public health problem.
Posey, Drew L; Blackburn, Brian G; Weinberg, Michelle; Flagg, Elaine W; Ortega, Luis; Wilson, Marianna; Secor, W Evan; Sanders-Lewis, Kolby; Won, Kimberly; Maguire, James H
Schistosomiasis and strongyloidiasis cause substantial morbidity and mortality among hundreds of millions of infected persons worldwide. In the United States, these infections are most commonly found among international travelers, immigrants, and refugees from areas of endemicity. Refugees resettled to the United States since 2000 include >3800 "Lost Boys and Girls" of Sudan and 8000 Somali Bantu. Many Lost Boys and Girls of Sudan reported chronic abdominal pain only since arrival, and some received diagnoses of schistosomiasis or strongyloidiasis. We assessed seroprevalence of these infections among these refugees and hypothesized an association between infection and abdominal pain. We offered a survey assessing chronic abdominal pain and serologic testing for schistosomiasis and strongyloidiasis to all 800 attendees of a Lost Boys and Girls of Sudan reunion in the United States. Serologic testing was performed on preimmigration specimens obtained from 100 United States-bound Somali Bantu refugees. Of the 462 Sudanese refugees (58%) tested, 44% and 46% were seropositive for schistosomiasis (primarily due to Schistosoma mansoni) and strongyloidiasis, respectively; 24% of those who tested positive for schistosomiasis had S. mansoni antigenemia. Forty-six percent reported chronic abdominal pain, which was not associated with either infection. Among 100 Somali Bantu, 73% and 23% tested seropositive for schistosomiasis (primarily due to Schistosoma haematobium) and strongyloidiasis, respectively. The high seroprevalence of schistosomiasis and strongyloidiasis among Sudanese Lost Boys and Girls and Somali Bantu refugees supports presumptive treatment for these refugees. Current refugee resettlement policies inadequately address these diseases; our data support consideration of predeparture presumptive therapy for all refugees from areas of endemicity.
Al-Waleedi, Ali A; El-Nimr, Nessrin A; Hasab, Ali A; Bassiouny, Hassan K; Al-Shibani, Latifa A
Schistosomiasis is one of the most important public health problems in Yemen. The prevalence of urinary schistosomiasis varies considerably across different parts of Yemen and was estimated to be 10% among schoolchildren in Sana'a. Praziquantel (PZQ) is highly effective against all five major human species of schistosomes. The aim of the present work was to estimate the prevalence of urinary schistosomiasis, describe the risk factors associated with its endemicity, and implement and assess a chemotherapeutic intervention using PZQ in a village in Yemen. The sample included 696 schoolchildren from a village in Abyan Governorate. During the baseline school survey, personal, sociodemographic, and environmental data, and data on practices in relation to water contact were collected from each study participant using a predesigned structured questionnaire. Urine samples from each participant were examined for macrohematuria and the presence of Schistosoma haematobium eggs. The chemotherapeutic intervention was assessed 3 and 6 months after the treatment and certain indicators were calculated. The prevalence of S. haematobium was 18.1%. The main significant risk factors were male sex; proximity of houses to water ponds; and using pond water for swimming, agricultural activities, and for bathing in houses. PZQ treatment reduced the prevalence of infection and decreased the prevalence of high-intensity infection. Survival analysis showed that the probability of residual infection also dropped after the treatment intervention. Male sex and using pond water for various activities were the main significant risk factors associated with urinary schistosomiasis. PZQ is still a cornerstone drug in reducing or eliminating morbidity associated with schistosomiasis infection. Health education programs tailored for the community are required for the control and prevention of urinary schistosomiasis. To address schoolchildren, school curricula should include lessons about urinary
Savioli, Lorenzo; Albonico, Marco; Colley, Daniel G; Correa-Oliveira, Rodrigo; Fenwick, Alan; Green, Will; Kabatereine, Narcis; Kabore, Achille; Katz, Naftale; Klohe, Katharina; LoVerde, Philip T; Rollinson, David; Stothard, J Russell; Tchuem Tchuenté, Louis-Albert; Waltz, Johannes; Zhou, Xiao-Nong
Schistosomiasis, one of the 17 neglected tropical diseases listed by the World Health Organization, presents a substantial public health and economic burden. Of the 261 million people requiring preventive chemotherapy for schistosomiasis in 2013, 92% of them lived in sub-Saharan Africa and only 12.7% received preventive chemotherapy. Moreover, in 2010, the WHO reported that schistosomiasis mortality could be as high as 280 000 per year in Africa alone.In May 2012 delegates to the sixty-fifth World Health Assembly adopted resolution WHA65.21 that called for the elimination of schistosomiasis, and foresees the regular treatment of at least 75% of school age children in at-risk areas. The resolution urged member states to intensify schistosomiasis control programmes and to initiate elimination campaigns where possible.Despite this, in June 2015, schistosomiasis was indicated to have the lowest level of preventive chemotherapy implementation in the spectrum of neglected tropical diseases. It was also highlighted as the disease most lacking in progress. This is perhaps unsurprising, given that it was also the only NTD with access to drug donations but without a coalition of stakeholders that collaborates to boost commitment and implementation.As a consequence, and to ensure that the WHO NTDs Roadmap Targets of 2012 and World Health Assembly Resolution WHA65.21 are met, the Global Schistosomiasis Alliance (GSA) has been set up. Diverse and representative, the GSA aims to be a partnership of endemic countries, academic and research institutions, international development agencies and foundations, international organizations, non-governmental development organizations, private sector companies and advocacy and resource mobilisation partners. Ultimately, the GSA calls for a partnership to work for the benefit of endemic countries by addressing health inequity and rural poverty.
Qian, Yi-Li; Wang, Wei; Hong, Qing-Biao; Liang, You-Sheng
To evaluate the outcomes of implementation of integrated schistosomiasis control strategy with emphasis on infectious source control using a bibliometric method. The literature pertaining to integrated schistosomiasis control strategy with emphasis on infectious source control was retrieved from CNKI, Wanfangdata, VIP, PubMed, Web of Science, BIOSIS and Google Scholar, and a bibliometric analysis of literature captured was performed. During the period from January 1, 2004 through September 30, 2014, a total of 94 publications regarding integrated schistosomiasis control strategy with emphasis on infectious source control were captured, including 78 Chinese articles (82.98%) and 16 English papers (17.02%). The Chinese literature was published in 21 national journals, and Chinese Journal of Schistosomiasis Control had the largest number of publications, consisting of 37.23% of total publications; 16 English papers were published in 12 international journals, and PLoS Neglected Tropical Diseases had the largest number of publications (3 publications). There were 37 affiliations publishing these 94 articles, and National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention (16 publications), Anhui Institute of Schistosomiasis Control (12 publications) and Hunan Institute of Schistosomiasis Control (9 publications) ranked top three affiliations in number of publications. A total of 157 persons were co-authored in these 94 publications, and Wang, Zhou and Zhang ranked top 3 authors in number of publications. The integrated schistosomiasis control strategy with emphasis on infectious source control has been widely implemented in China, and the achievements obtained from the implementation of this strategy should be summarized and transmitted internationally.
De-Rong, Hang; Yi-Xin, Huang; Yao-Bao, Liu; Xu, Zhang; Yi-Qing, Xie; Wei-Gang, Yin; Kai, Tang; Lian-Heng, Zhang; Dao-Kuan, Sun
To understand the schistosomiasis control knowledge, attitude, and practice (KAP), and influencing factors of behaviors among residents in Jiangsu Province, so as to provide the evidence for making effective health education and health promotion models. The probability proportionate to size sampling (PPS) and multi-stage sampling methods were adopted to sample the research objects. A questionnaire survey of schistosomiasis control KAP was conducted in the residents of 16 to 69 years old in schistosomiasis endemic areas of Jiangsu Province, and the results were statistically analyzed. The total awareness rate of the participants was 95.98% for schistosomiasis control knowledge. The correct rates of attitude and practice were 89.06% and 77.43%, respectively. The awareness/correct rates of knowledge, attitude and practice reduced in turns significantly ( χ 2 =1 282.96, P education level increasing, their practice correct rate rose, and the participants with the college degree or above had a higher correct rate compared to illeterate ones ( OR = 6.411, 95% CI : 4.896-8.395). The practice correct rate of the fisher-men and boatmen was only 5.1% of the rate of the farmers ( OR = 0.051, 95% CI : 0.029-0.091). The total awareness rate of basic knowledge of schistosomiasis prevention and control in the residents of Jiangsu Province has reached the requirements in the "National Schistosomiasis Control Long-term Planning Outline (2004-2015)", but the correct rate of behaviors is low. The education level, occupation and residential areas affect the health behaviors of schistosomiasis prevention and control. Therefore, it is necessary to carry out targeted health promotion activities to promote the formation of healthy lifestyle and behaviors.
Erikstrup, C.; Kallestrup, P.; Zinyama-Gutsire, R.B.
We previously reported that treatment for schistosomiasis in persons infected with human immunodeficiency virus 1 (HIV-1) attenuated HIV replication as measured by plasma HIV RNA. We investigated systemic inflammation as measured by plasma levels of soluble tumor necrosis factor-alpha receptor II...
Gu, Yong; Li, Da-Ming; Jiang, Jian; Ho, Chun; Tang, Chuan-Xing; Liu, Ke-Gang
To understand the status of schistosomiasis knowledge and behavior and analyze the regional difference of population in Mianzhu City. Nine towns were divided into 3 groups, and each group had 3 towns. In Group I , there were 5 or more than 5 advanced schistosomiasis patients each town; in Group II , there were 1-4 advanced patients each town; in Group III, there was no advanced patient. A total of 2 743 residents were investigated with questionnaire in all the 9 towns. The overall awareness rate of schistosomiasis control knowledge was 88.12%, and the awareness rates of schistosomiasis control knowledge were 94.55%, 88.21% and 81.10% in Group I , Group II and Group III respectively. The total formation rate of correct behavior was 68.10%, and the formation rates of correct behavior were 73.18%, 67.05% and 63.65% in Group I , Group II and Group III respectively. The awareness rates of schistosome transmission were 95.99%, 89.48% and 79.67%; the awareness rates of Oncomelania snails were 87.67%, 82.54% and 73.92%; the awareness rates of schistosomiasis harm were 95.68%, 93.99% and 80.88%; the rates of residents who thought that schistosomiasis patients did not affect others were 9.97%, 12.83% and 15.58%; the rates of residents who did not know the information of the snails should report to which department were 7.91%, 11.33%, 15.69%; the rates of residents who often had wild bowels were 6.17%, 8.79% and 11.38%; the rates of residents who often washed their hands and feet in ditches and ponds were 58.68%, 58.27%, 61.22%; the rates of residents who would not accept the schistosomiasis checks were 5.86%, 5.66%, 11.49% in Group I , Group II and Group III respectively. As a whole, the population of Mianzhu City has positive behaviors to schistosomiasis control. We should still enhance the schistosomiasis control education and interventions according to the characteristics of the different townships.
Song, Langui; Wu, Xiaoying; Zhang, Beibei; Liu, Jiahua; Ning, An; Wu, Zhongdao
The prevalence and intensity of schistosomiasis has dropped dramatically in China due to an effective integrated control program. However, advanced schistosomiasis is becoming a key challenge on the road to elimination. The aims of this study were to compare the disease condition between advanced cases under the general assistance program (GAP) and free treatment program (FTP) and to determine whether the FTP should be popularized to provide an objective reference for policymakers in China's advanced schistosomiasis control program. One hundred and ninety-four patients with schistosomiasis japonica who were enrolled in the GAP or FTP participated in this study. Little significant difference was observed in the potential confounders, including general characteristics, comorbidities, and lifestyle, indicating a similar effect on the pathology of liver damage caused by schistosome infection. There was no apparent difference in the incidence of common clinical symptoms. Furthermore, no significant difference was observed in the ultrasound findings, implying that the GAP and FTP groups shared a similar degree of liver lesion. With the exception of the abnormal rates of aspartate aminotransferase (AST), alkaline phosphatase (ALP), and hyaluronic acid (HA), the other serological indicators were comparable between the groups. Overall, the FTP is not a better option for controlling advanced schistosomiasis in China. It is important to reveal the precise mechanism underlying the pathogenesis of advanced schistosomiasis so that specific approaches to treating and preventing the development of advanced schistosomiasis can be developed and schistosomiasis can be eliminated in China.
Zilton A. Andrade
Full Text Available A model of acute schistosomiasis of the mouse was used to observe whether curative treatment would be followed by an enhancement of the hepatic and splenic lesions, as a consequence of the massive destruction of worms and eggs within the portal system. Mice infected with 50 cercariae of Schistosoma mansoni were treated with both oxamniquine and praziquantel on the 50th day of infection and submitted to a sequential histologic examination from the 2nd to the 45th day after treatment. Although severe focal lesions due to dead and disintegranting worms were present in the livers of the treated animals, no aggravation of the general changes (reative hepatitis and splenitis, or periovular granulomas was seen in comparison with a control non-treated group. Of 50 animals treated during the acute phase of schistosomiasis only one died espontaneously, while 16 ou of 30 infected controls died before the end of the experiment. The present investigation indicates that curative treatment during the acute phase of schistosomiasis does not enhance previous lesions at first and results in progressive disappearance of the lesions starting six days following chemotherapy.Foi utilizado um modelo de esquistossomose aguda do camundongo para testar se o tratamentop curativo da parasitose nesta fase poderia produzir uma exacerbação das lesões hepáticas e esplênicas, em virtude da destruição maciça de vermes e ovos nointerior do sistema porta. Camundongos infectados com 50 cercárias do Schistosoma mansoni foram tratados no 50º dia da infecção por uma combinação de oxamniquine e praziquantel e submetidos a exames histopatológicos seqüenciados desde o 2º até o 45º dia após o tratamento. Muito embora tenham sido encontrados lesões focais intensas causadas por vermes mortos no interior do fígado, não foi encontrada qualquer evidência de agravamento das lesões gerais (hepatite reacional e esplenite, ou nos granulomas periovulares quando se fez
Wang, Wei; Liang, You-Sheng; Hong, Qing-Biao; Dai, Jian-Rong
Schistosomiasis is a major disease of public health importance in humans occurring in 76 countries of the tropics and sub-tropics. In China, schistosomiasis japonica is one of the highest priorities in communicable disease control defined by the central government. Since 1970s, the habitats of Biomphalaria straminea, an intermediate host of Schistosoma mansoni in South America, have been identified in Hong Kong Special Administrative Region and Shenzhen city, Guangdong province of China. With the sharp growth in the China-aided projects in Africa and labor services export to Africa, a gradual rise in the cases infected with S. haematobium or S. mansoni is reported in those returning from Africa to China. The existence of intermediate snail hosts and import of infectious source of schistosomiasis results in concern about the transmission of African schistosomiasis in mainland China in the context of global climate change. This paper evaluates the risk of transmission of African schistosomiasis in China, and proposes countermeasures and research priorities to tackle the risk.
N'Diaye, Monique; Dioukhane, Elhadji M; Ndao, Babacar; Diedhiou, Kemo; Diawara, Lamine; Talla, Idrissa; Vernet, Charlotte; Bessin, François; Barbier, Dominique; Dewavrin, Patrick; Klotz, Francis; Georges, Pierre
Schistosomiasis is the second most significant parasitic disease in children in several African countries. For this purpose, the "Programme National de Lutte contre les Bilharzioses" (PNLB) was developed in partnership with the World Health Organization (WHO) to control this disease in Senegal. However, geographic isolation of Bedik ethnic groups challenged implementation of the key elements of the schistosomiasis program in eastern Senegal, and therefore, a hospital was established in Ninefescha to improve access to health care as well as laboratory support for this population. The program we have implemented from 2008 in partnership with the PNLB/WHO involved campaigns to 1) evaluate schistosomiasis prevalence in children of 53 villages around Ninefescha hospital, 2) perform a mass drug administration following the protocol established by the PNLB in school-aged children, 3) monitor annual prevalence, 4) implement health education campaigns, and 5) oversee the building of latrines. This campaign led to a drop in schistosomiasis prevalence but highlighted that sustainable schistosomiasis control by praziquantel treatment, awareness of the use of latrines, and inhabitants' voluntary commitment to the program are crucial to improve Schistosoma elimination. Moreover, this study revealed that preschool-aged children, for whom praziquantel was not recommended until 2014 in Senegal, constituted a significant reservoir for the parasite. © The American Society of Tropical Medicine and Hygiene.
Cronin, Thomas; Sheppard, James; de Wildt, Gilles
Schistosomiasis is a chronic and debilitating parasitic disease acquired through contact with infested freshwater. An essential component of its control is passive case finding, which, in order to be effective, requires a detailed understanding of health-seeking behaviour. This study aimed to systematically review evidence on health-seeking behaviour for schistosomiasis, in order to determine factors influencing use or non-use of modern health services for the infection. Quantitative, qualitative and mixed method studies reporting on factors related to seeking treatment from modern health services for schistosomiasis were obtained, combining electronic and hand searching. Data extraction and quality assessment of the included articles were performed, with all studies qualitatively analysed using thematic synthesis. A total of 19 studies were included in the review. Six themes were identified from the analysis: biomedical knowledge on schistosomiasis, perceptions of modern treatment and health services, financial considerations of treatment, perceptions on the symptoms, stigma of the infection, and physical location and community. These findings were consistent across studies of different design, setting and quality. Many of the themes identified echo existing literature on health-seeking behaviour. The synthesis also highlighted the role of stigma, and aspects of the physical location and community that may affect treatment-seeking for schistosomiasis. Health education programmes that intend to improve the utilisation of modern health services for the infection need to acknowledge the multiple determinants influencing their use. Future research should move beyond describing health-seeking behaviour to identifying the factors that underlay such behaviour. PMID:24839538
Rose E. Donohue
Full Text Available Schistosomiasis is a parasitic disease endemic to Tanzania and other countries of the global south, which is currently being addressed through preventive chemotherapy campaigns. However, there is growing recognition that chemotherapy strategies will need to be supplemented to sustainably control and eventually eliminate the disease. There remains a need to understand the factors contributing to continued transmission in order to ensure the effective configuration and implementation of supplemented programs. We conducted a cross-sectional questionnaire, to evaluate the biosocial determinants facilitating the persistence of schistosomiasis, among 1704 Tanzanian schoolchildren residing in two districts undergoing a preventive chemotherapeutic program: Rufiji and Mkuranga. A meta-analysis was carried out to select the diagnostic questions that provided a likelihood for predicting infection status. We found that self-reported schistosomiasis continues to persist among the schoolchildren, despite multiple rounds of drug administration.Using mixed effects logistic regression modeling, we found biosocial factors, including gender, socio-economic status, and water, sanitation, and hygiene (WASH-related variables, were associated with this continued schistosomiasis presence. These findings highlight the significant role that social factors may play in the persistence of disease transmission despite multiple treatments, and support the need not only for including integrated technical measures, such as WASH, but also addressing issues of poverty and gender when designing effective and sustainable schistosomiasis control programs.
McManus, Donald P; Gray, Darren J; Li, Yuesheng; Feng, Zheng; Williams, Gail M; Stewart, Donald; Rey-Ladino, Jose; Ross, Allen G
The potential impact of the Three Gorges Dam (TGD) on schistosomiasis transmission in China has invoked considerable global concern. The TGD will result in changes in the water level and silt deposition downstream, favoring the reproduction of Oncomelania snails. Combined with blockages of the Yangtze River's tributaries, these changes will increase the schistosomiasis transmission season within the marshlands along the middle and lower reaches of the Yangtze River. The changing schistosome transmission dynamics necessitate a comprehensive strategy to control schistosomiasis. This review discusses aspects of the epidemiology and transmission of Schistosoma japonicum in China and considers the pathology, clinical outcomes, diagnosis, treatment, immunobiology, and genetics of schistosomiasis japonica together with an overview of current progress in vaccine development, all of which will have an impact on future control efforts. The use of synchronous praziquantel (PZQ) chemotherapy for humans and domestic animals is only temporarily effective, as schistosome reinfection occurs rapidly. Drug delivery requires a substantial infrastructure to regularly cover all parts of an area of endemicity. This makes chemotherapy expensive and, as compliance is often low, a less than satisfactory control option. There is increasing disquiet about the possibility that PZQ-resistant schistosomes will develop. Consequently, as mathematical modeling predicts, vaccine strategies represent an essential component in the future control of schistosomiasis in China. With the inclusion of focal mollusciciding, improvements in sanitation, and health education into the control scenario, China's target of reducing the level of schistosome infection to less than 1% by 2015 may be achievable.
Monica L Richardson
Full Text Available Over 112 million people worldwide are infected with Schistosoma haematobium, one of the most prevalent schistosome species affecting humans. Female genital schistosomiasis (FGS occurs when S. haematobium eggs are deposited into the female reproductive tract by adult worms, which can lead to pelvic pain, vaginal bleeding, genital disfigurement and infertility. Recent evidence suggests co-infection with S. haematobium increases the risks of contracting sexually transmitted diseases such as HIV. The associated mechanisms remain unclear due to the lack of a tractable animal model. We sought to create a mouse model conducive to the study of immune modulation and genitourinary changes that occur with FGS.To model FGS in mice, we injected S. haematobium eggs into the posterior vaginal walls of 30 female BALB/c mice. A control group of 20 female BALB/c mice were injected with uninfected LVG hamster tissue extract. Histology, flow cytometry and serum cytokine levels were assessed at 2, 4, 6, and 8 weeks post egg injection. Voiding studies were performed at 1 week post egg injection.Vaginal wall injection with S. haematobium eggs resulted in synchronous vaginal granuloma development within 2 weeks post-egg injection that persisted for at least 6 additional weeks. Flow cytometric analysis of vaginal granulomata revealed infiltration by CD4+ T cells with variable expression of the HIV co-receptors CXCR4 and CCR5. Granulomata also contained CD11b+F4/80+ cells (macrophages and eosinophils as well as CXCR4+MerTK+ macrophages. Strikingly, vaginal wall-injected mice featured significant urinary frequency despite the posterior vagina being anatomically distant from the bladder. This may represent a previously unrecognized overactive bladder response to deposition of schistosome eggs in the vagina.We have established a new mouse model that could potentially enable novel studies of genital schistosomiasis in females. Ongoing studies will further explore the
Full Text Available Among millions of people who suffer from schistosomiasis in China, adolescents are at increased risk to be infected. However, there is a lack of theory-guided behavioral prevention intervention programs to protect these adolescents. This study attempted to apply the Protection Motivation Theory (PMT in predicting intentions to engage in protective behaviors against schistosomiasis infection.The participants were selected using the stratified cluster sampling method. Survey data were collected using anonymous self-reported questionnaire. The advanced structural equation modeling (SEM method was utilized to assess the complex relationship among schistosomiasis knowledge, previous risk exposure and protective measures in predicting intentions to engage in protective behavior through the PMT constructs.Approximately 70% of participants reported they were always aware of schistosomiasis before exposure to water with endemic schistosomiasis, 6% of the participants reported frequency of weekly or monthly prior exposure to snail-conditioned water. 74% of participants reported having always engaged in protective behaviors in the past three months. Approximately 7% were unlikely or very unlikely to avoid contact with snail-conditioned water, and to use protective behaviors before exposure. Results from SEM analysis indicated that both schistosomiasis knowledge and prior exposure to schistosomiasis were indirectly related to behavior intentions through intrinsic rewards and self-efficacy; prior protective behaviors were indirectly related to behavior intentions through severity, intrinsic rewards and self-efficacy, while awareness had an indirect relationship with behavior intentions through self-efficacy. Among the seven PMT constructs, severity, intrinsic rewards and self-efficacy were significantly associated with behavior intentions.The PMT can be used to predict the intention to engage in protective behaviors against schistosomiasis. Schistosomiasis
Xiao, Han; Li, Shiyue; Chen, Xinguang; Yu, Bin; Gao, Mengting; Yan, Hong; Okafor, Chukwuemeka N
Among millions of people who suffer from schistosomiasis in China, adolescents are at increased risk to be infected. However, there is a lack of theory-guided behavioral prevention intervention programs to protect these adolescents. This study attempted to apply the Protection Motivation Theory (PMT) in predicting intentions to engage in protective behaviors against schistosomiasis infection. The participants were selected using the stratified cluster sampling method. Survey data were collected using anonymous self-reported questionnaire. The advanced structural equation modeling (SEM) method was utilized to assess the complex relationship among schistosomiasis knowledge, previous risk exposure and protective measures in predicting intentions to engage in protective behavior through the PMT constructs. Approximately 70% of participants reported they were always aware of schistosomiasis before exposure to water with endemic schistosomiasis, 6% of the participants reported frequency of weekly or monthly prior exposure to snail-conditioned water. 74% of participants reported having always engaged in protective behaviors in the past three months. Approximately 7% were unlikely or very unlikely to avoid contact with snail-conditioned water, and to use protective behaviors before exposure. Results from SEM analysis indicated that both schistosomiasis knowledge and prior exposure to schistosomiasis were indirectly related to behavior intentions through intrinsic rewards and self-efficacy; prior protective behaviors were indirectly related to behavior intentions through severity, intrinsic rewards and self-efficacy, while awareness had an indirect relationship with behavior intentions through self-efficacy. Among the seven PMT constructs, severity, intrinsic rewards and self-efficacy were significantly associated with behavior intentions. The PMT can be used to predict the intention to engage in protective behaviors against schistosomiasis. Schistosomiasis intervention
Zhou, Xiao-Nong; Li, Shi-Zhu
Based on theoretic management and quality control of the project, this paper summarizes the 3 major management modes in the national schistosomiasis control programme of China, and the health system management mechanisms under the guidance of national legislation, national programme and national standard and regulation. It is revealed that scientific assessment and assurance of the quality of each control programme is one of the highlighted concerns in the management mode of schistosomiasis control in China after a case study on mollusciciding project. Therefore, it is recommended that the actions, including management of every step in the project management of schistosomiasis control, formulation of operation procedure for each control programme and standardization of the working flow for professional staff, are not only a prerequistite to achievment-based evaluation, but also the key to ensure the quality of every control intervention and present the actual control effect.
Bassiouny, H K; Hasab, A A; El-Nimr, N A; Al-Shibani, L A; Al-Waleedi, A A
Schistosomiasis ranks second to malaria in terms of socioeconomic and public health importance in Yemen. This study assessed the validity of a morbidity questionnaire and urine reagent strips as a rapid tool for screening schoolchildren for urinary schistosomiasis as compared with the presence of eggs in urine as the gold-standard parasitological diagnosis. The study examined urine samples and interviewed 696 children (mean age 12.5 years) attending a primary-preparatory school in south Yemen. Urinary schistosomiasis was confirmed in 126 (18.1%) children. Diagnostic performance was poor for 2 items in the morbidity questionnaire (self-reported history of previous infection and self-reported history of antischistosomal treatment). However, self-reported dysuria, self-reported haematuria in the questionnaire and microhaematuria by reagent strips (alone or with macrohaematuria) revealed good diagnostic performance. The results indicated that reagent strips are a valid method for detection of microhaematuria for identifying individuals and communities infected with Schistosoma haematobium.
Beltrame, Anna; Buonfrate, Dora; Gobbi, Federico; Angheben, Andrea; Marchese, Valentina; Monteiro, Geraldo Badona; Bisoffi, Zeno
The prevalence of schistosomiasis among recent refugees from sub-Saharan Africa in Italy is unknown. This is a retrospective review of African immigrants screened at Centre for Tropical Diseases of Negrar from March 2014 to February 2016. Of the 373 immigrants tested, 34% were positive at least at one schistosomiasis test. The proportion of positive ELISA serology was 103/373 (27.6%). At microscopy, infected subjects were 65/373 (17.4%), (51% Schistosoma haematobium, 38% Schistosoma mansoni, 11% both). CCA antigen for S. mansoni was positive in 47/373 individuals (12.6%). We found a particularly high positivity rate in subjects from Mali (72.1%) and Ivory Coast (48%). This "hidden epidemic" of schistosomiasis cannot be longer neglected, considering the risk of severe complications, and the effective and inexpensive treatment available.
Lin, Changwei; Li, Xiaorong; Guo, Yihang; Hu, Gui; Zhang, Yi; Yang, Kaiyan; Gan, Yi; Zhou, Jianyu; Lv, Lv; Gao, Kai; Du, Juan
Both mucinous cystadenoma of the appendix and intestinal schistosomiasis are rare lesions. We report a rare case of simultaneous giant mucinous cystadenoma of the appendix and intestinal schistosomiasis. A 64-year-old man from China presented with a one-year history of pain in the right lower quadrant of the abdomen. There were no other pertinent historical findings, other than schistosomiasis. Imaging showed a large, tubular, mesenteric cystic structure extending downwards from the inferior wall of the cecum. Right hemicolectomy was performed for the appendiceal tumor. The final pathological diagnosis was mucinous cystadenoma with calcified Schistosome eggs within the mucosa and submucosa of the appendix, small intestine, colon, and lymph nodes. We deduced that the pathogenesis of appendiceal mucinous cystadenoma in our case was Schistosome eggs causing luminal obstruction, finally resulting in intraluminal accumulation of mucoid material. Postoperatively, the patient recovered well.
Stensgaard, Anna-Sofie; Kristensen, Thomas K.; Jørgensen, Aslak
the distribution of human schistosomiasis and biogeographical patterns of freshwater snail and mammal species richness in Uganda. We found that the association between estimated snail richness and human infection was best described by a negative correlation in non-spatial bi- and multivariate logistic mixed effect...... models. However, this association lost significance after the inclusion of a spatial component in a full geostatistical model, highlighting the importance of accounting for spatial correlation to obtain more precise parameter estimates. Furthermore, we found no significant relationships between mammal...... richness and schistosomiasis risk. We discuss the limitations of the data and methods used to test the decoy hypothesis for schistosomiasis, and highlight key future research directions that can facilitate more powerful tests of the decoy effect in snail-borne infections, at geographical scales...
Saarnak, Christopher; Braae, Uffe Christian; Mukaratirwa, S.
considered, on national scale, to be co-endemic with schistosomiasis. The co-endemicity dataset was then combined with modelled data on population density for 2015 derived from the WorldPop database. We used the open source GIS software QGIS and GRASS to overlay the two datasets and identified the number......). However, the drug used for this, praziquantel, has been reported to cause dramatic side effects among people suffering from neurocysticercosis. Both diseases are presumed to be widely distributed on the continent, but the co-endemicity is unclear. We carried out a meta-analysis of the literature of T......This study investigates the number of people in Sub-Saharan Africa living in areas where two neglected tropical diseases, cysticercosis and schistosomiasis, are co-endemic. The World Health Organisation is aiming for elimination of schistosomiasis by 2020 through mass drug administration (MDA...
Sokolow, Susanne H.; Wood, Chelsea L.; Jones, Isabel J.; Lafferty, Kevin D.; Kuris, Armand; Hsieh, Michael H.; De Leo, Giulio A.
Control strategies to reduce human schistosomiasis have evolved from ‘snail picking’ campaigns, a century ago, to modern wide-scale human treatment campaigns, or preventive chemotherapy. Unfortunately, despite the rise in preventive chemotherapy campaigns, just as many people suffer from schistosomiasis today as they did 50 years ago. Snail control can complement preventive chemotherapy by reducing the risk of transmission from snails to humans. Here, we present ideas for modernizing and scaling up snail control, including spatiotemporal targeting, environmental diagnostics, better molluscicides, new technologies (e.g., gene drive), and ‘outside the box’ strategies such as natural enemies, traps, and repellants. We conclude that, to achieve the World Health Assembly’s stated goal to eliminate schistosomiasis, it is time to give snail control another look.
Ciddio, Manuela; Gatto, Marino, E-mail: firstname.lastname@example.org; Casagrandi, Renato, E-mail: email@example.com [Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Via Ponzio 34/5, 20133 Milano (Italy); Mari, Lorenzo [Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Via Ponzio 34/5, 20133 Milano (Italy); Laboratory of Ecohydrology, ECHO/IIE/ENAC, École Polytechnique Fédérale de Lausanne, Station 2, 1015 Lausanne (Switzerland); Rinaldo, Andrea [Laboratory of Ecohydrology, ECHO/IIE/ENAC, École Polytechnique Fédérale de Lausanne, Station 2, 1015 Lausanne (Switzerland); Dipartimento di Ingegneria Civile, Edile ed Ambientale, Università di Padova, Via Loredan 20, 35131 Padova (Italy)
Schistosomiasis is one of the most widespread public health problems in the world. In this work, we introduce an eco-epidemiological model for its transmission and dynamics with the purpose of explaining both intra- and inter-annual fluctuations of disease severity and prevalence. The model takes the form of a system of nonlinear differential equations that incorporate biological complexity associated with schistosome's life cycle, including a prepatent period in snails (i.e., the time between initial infection and onset of infectiousness). Nonlinear analysis is used to explore the parametric conditions that produce different temporal patterns (stationary, endemic, periodic, and chaotic). For the time-invariant model, we identify a transcritical and a Hopf bifurcation in the space of the human and snail infection parameters. The first corresponds to the occurrence of an endemic equilibrium, while the latter marks the transition to interannual periodic oscillations. We then investigate a more realistic time-varying model in which fertility of the intermediate host population is assumed to seasonally vary. We show that seasonality can give rise to a cascade of period-doubling bifurcations leading to chaos for larger, though realistic, values of the amplitude of the seasonal variation of fertility.
Oliveira Ana Luna de
Full Text Available In order to evaluate Callithrix jacchus as an animal model for mansoni schistosomiasis, a group of 10 male animals were once percutaneously exposed to 250 cercariae of the Schistosoma mansoni SLM (São Lourenço da Mata strain. Animals were periodically bled for measuring serum level of enzymes and proteins and for blood cell counting. When comparing pre-infection to post-infection values, a significant increase was found for alkaline phosphatase at 15 to 120 days p.i., differential counts of eosinophil at 45 and 60 days, and total protein and global eosinophil counts at 120 days. No Schistosoma mansoni eggs were found in stools. Adult worms of small size were recovered from five animals. At day 120, the number of Schistosoma mansoni eggs/g of tissue was 0-289.7 (liver, 0-30.1 (large intestine and 0-171.4 (small intestine. These findings lead us to classify Callithrix jacchus as a non-permissive host to the SLM strain of Schistosoma mansoni.
Full Text Available The activity of lovastatin associated with oxamniquine or praziquantel against schistosomiasis mansoni was evaluated in mice infected with Schistosoma mansoni. Forty days after infection, mice were treated with lovastatin, 400 mg/kg for five consecutive days by oral route, and on the last day of this sequence with 50 mg/kg oxamniquine or with 200 mg/kg praziquantel, both by oral route, single dose. Fifteen days later, the animals were perfused in parallel with an untreated control group. Studies were carried out in vitro, using lovastatin in culture medium containing S. mansoni worms proceeding from experimentally infected mice. In the in vivo trials, the association of lovastatin with oxamniquine or praziquantel did not show any additive action, but there were oogram changes when lovastatin was associated with oxamniquine. In vitro lovastatin was able to interrupt the maturation of S. mansoni eggs, which remained at the 1st or 2nd stages, depending on the dose used. The total number of morphologically dead eggs found in culture of worms exposed to 2 µg/ml or 4 µg/ml concentrations of lovastatin was significantly higher than the number of viable eggs. Using the probe Hoescht 33258 it was observed that 70% of the eggs considered morphologically viable in the treated groups (against 16% in the control group were labeled, indicating that the majority of the viable eggs had membrane permeability increased due to lovastatin action.
Laís Bastos da Fonseca
Full Text Available Schistosomiasis is a parasitic disease that, according to the World Health Organization, constitutes a major public health problem associated with severe morbidity, mostly children in preschool age. The administration of drugs in children always constitutes a difficult task, especially when formulations are not developed specifically for pediatric use, when high doses of drug are required and the drug has a bitter taste, as in the case of praziquantel. Polymer nanoparticles are promising systems for development of encapsulated drugs with low water solubility and bitter taste, due to the good physical and chemical stability, adequate biocompatibility and simple manufacturing processes. Moreover, they can enhance the bioavailabili-ty and reduce variability of treatment among patients. Poly (methyl methacrylate doped with praziquantel was produced through a miniemulsion polymerization pro-cess to compose a pediatric pharmaceutical suspension. Nanoparticles were cha-racterized in terms of physico-chemical properties, toxicological properties and biological activity in mice, being concluded that obtained results were satisfactory. The results were encapsulation rate around 90%, absence of chemical interaction drug - polymer and the presence of biological activity. A collaborative approach was used for this development, involving national partnerships and independent funding mechanisms, a powerful pathway for development of drugs for neglected diseases.
Tzanetou, Konstantina; Astriti, Myrto; Delis, Vassilios; Moustakas, George; Choreftaki, Theodosia; Papaliodi, Eugenia; Sarri, Katerina; Adamis, George
A case is presented of intestinal schistosomiasis due to both Schistosoma intercalatum and Schistosoma mansoni in a 30-year-old man from Senegal with discussion of diagnostic approach, species identification and determination of the effect of treatment. The patient was admitted to hospital for investigation of renal failure, arterial hypertension and hypereosinophilia. Repeated stool examinations for ova and parasites were negative. Ultrasonography (US) and computed tomography (CT) of the abdomen showed no abnormalities. US of the urinary tract showed kidneys of borderline size with increased echogenicity. Cystoscopy and histopathological examination of bladder biopsy specimens were normal. Flexible colonoscopy revealed numerous nodular lesions in the rectosigmoid region and a few similar lesions in the transverse colon, the histopathological examination of which showed deposition of Schistosoma ova with granuloma formation. Examination of multiple crush biopsy specimens from the rectosigmoid region revealed numerous granulomas formed around Schistosoma eggs which had a terminal spine and were identified as S. intercalatum (longer than Schistosoma haematobium and with a slightly curved terminal spine) and a very few S. mansoni eggs. Crush biopsies from the lesions in the transverse colon showed only S. mansoni eggs. In conclusion, the examination of multiple crush biopsy specimens is a very sensitive and specific technique for species identification of Schistosoma, especially in mixed infections, and for defining the location and extent of the granulomas evoked by each species. Copyright 2010 Elsevier Ltd. All rights reserved.
Gardenia Braz Figueiredo Carvalho
Full Text Available The development of a more sensitive diagnostic test for schistosomiasis is needed to overcome the limitations of the use of stool examination in low endemic areas. Using parasite antigens in enzyme linked immunosorbent assay is a promising strategy, however a more rational selection of parasite antigens is necessary. In this study we performed in silico analysis of the Schistosoma mansoni genome, using SchistoDB database and bioinformatic tools for screening immunogenic antigens. Based on evidence of expression in all parasite life stage within the definitive host, extracellular or plasmatic membrane localization, low similarity to human and other helminthic proteins and presence of predicted B cell epitopes, six candidates were selected: a glycosylphosphatidylinositol-anchored 200 kDa protein, two putative cytochrome oxidase subunits, two expressed proteins and one hypothetical protein. The recognition in unidimensional and bidimensional Western blot of protein with similar molecular weight and isoelectric point to the selected antigens by sera from S. mansoni infected mice indicate a good correlation between these two approaches in selecting immunogenic proteins.
Jamille Souza Fernandes
Full Text Available A major issue with Schistosoma mansoni infection is the development of periportal fibrosis, which is predominantly caused by the host immune response to egg antigens. Experimental studies have pointed to the participation of monocytes in the pathogenesis of liver fibrosis. The aim of this study was to characterize the subsets of monocytes in individuals with different degrees of periportal fibrosis secondary to schistosomiasis. Monocytes were classified into classical (CD14++CD16−, intermediate (CD14++CD16+, and nonclassical (CD14+CD16++. The expressions of monocyte markers and cytokines were assessed using flow cytometry. The frequency of classical monocytes was higher than the other subsets. The expression of HLA-DR, IL-6, TNF-α, and TGF-β was higher in monocytes from individuals with moderate to severe fibrosis as compared to other groups. Although no differences were observed in receptors expression (IL-4R and IL-10R between groups of patients, the expression of IL-12 was lower in monocytes from individuals with moderate to severe fibrosis, suggesting a protective role of this cytokine in the development of fibrosis. Our data support the hypothesis that the three different monocyte populations participate in the immunopathogenesis of periportal fibrosis, since they express high levels of proinflammatory and profibrotic cytokines and low levels of regulatory markers.
Walz, Yvonne; Wegmann, Martin; Dech, Stefan; Vounatsou, Penelope; Poda, Jean-Noël; N'Goran, Eliézer K; Utzinger, Jürg; Raso, Giovanna
Schistosomiasis is the most widespread water-based disease in sub-Saharan Africa. Transmission is governed by the spatial distribution of specific freshwater snails that act as intermediate hosts and human water contact patterns. Remote sensing data have been utilized for spatially explicit risk profiling of schistosomiasis. We investigated the potential of remote sensing to characterize habitat conditions of parasite and intermediate host snails and discuss the relevance for public health. We employed high-resolution remote sensing data, environmental field measurements, and ecological data to model environmental suitability for schistosomiasis-related parasite and snail species. The model was developed for Burkina Faso using a habitat suitability index (HSI). The plausibility of remote sensing habitat variables was validated using field measurements. The established model was transferred to different ecological settings in Côte d'Ivoire and validated against readily available survey data from school-aged children. Environmental suitability for schistosomiasis transmission was spatially delineated and quantified by seven habitat variables derived from remote sensing data. The strengths and weaknesses highlighted by the plausibility analysis showed that temporal dynamic water and vegetation measures were particularly useful to model parasite and snail habitat suitability, whereas the measurement of water surface temperature and topographic variables did not perform appropriately. The transferability of the model showed significant relations between the HSI and infection prevalence in study sites of Côte d'Ivoire. A predictive map of environmental suitability for schistosomiasis transmission can support measures to gain and sustain control. This is particularly relevant as emphasis is shifting from morbidity control to interrupting transmission. Further validation of our mechanistic model needs to be complemented by field data of parasite- and snail
Full Text Available Schistosomiasis is the most widespread water-based disease in sub-Saharan Africa. Transmission is governed by the spatial distribution of specific freshwater snails that act as intermediate hosts and human water contact patterns. Remote sensing data have been utilized for spatially explicit risk profiling of schistosomiasis. We investigated the potential of remote sensing to characterize habitat conditions of parasite and intermediate host snails and discuss the relevance for public health.We employed high-resolution remote sensing data, environmental field measurements, and ecological data to model environmental suitability for schistosomiasis-related parasite and snail species. The model was developed for Burkina Faso using a habitat suitability index (HSI. The plausibility of remote sensing habitat variables was validated using field measurements. The established model was transferred to different ecological settings in Côte d'Ivoire and validated against readily available survey data from school-aged children.Environmental suitability for schistosomiasis transmission was spatially delineated and quantified by seven habitat variables derived from remote sensing data. The strengths and weaknesses highlighted by the plausibility analysis showed that temporal dynamic water and vegetation measures were particularly useful to model parasite and snail habitat suitability, whereas the measurement of water surface temperature and topographic variables did not perform appropriately. The transferability of the model showed significant relations between the HSI and infection prevalence in study sites of Côte d'Ivoire.A predictive map of environmental suitability for schistosomiasis transmission can support measures to gain and sustain control. This is particularly relevant as emphasis is shifting from morbidity control to interrupting transmission. Further validation of our mechanistic model needs to be complemented by field data of parasite- and
El-Shahawy I. S.
Full Text Available Schistosomiasis is a major cause of morbidity and mortality and has been estimated to infect over 200 million people. Diagnosis of schistosomiasis by detection of specific antibodies is likely to be more sensitive than the traditional method of diagnosis by detection of eggs in stool or urine. Therefore the present study was the first attempt to highlight the seroepidemiology of schistosomiasis among the general population of Najran City, southern of Saudi Arabia, as well as to achieve the performance of the diagnostic tests used. A total of 180 participants attending King Khaled hospital in Najran Province, Saudi Arabia, over a one year period, from September 2013 to September 2014 were screened for the presence of Schistosoma antibody in their blood serum using an indirect hemagglutination assay (IHA. Specific immunoglobulin (Ig G antibody was evaluated using an enzyme-linked immunosorbent assay (ELISA. Out of the 180 samples of sera tested using IHA, 32 (20 % were found to be positive with a titer ranging from 1:160 to 1:1280, while 42(23.2 % revealed Schistosoma IgG. A positive relationship was found between the seroprevalence of schistosomiasis and age of tested participants, especially in the age group of 20-40 years old. Additionally, prevalence of infection was more in males (36 % than females (7.5 %, and showed statistical significance (P < 0.001. Similarly, there was significant association between the presence of Schistosoma antibodies and the nationality of residence, and education of participants (P < 0.05. The current investigation reveals an alarmingly high prevalence of schistosomiasis among participants in Najran, southern region of Saudi Arabia and this supports an urgent need to re-evaluate the current control measures and implement an integrated, targeted and effective schistosomiasis control measures.
Full Text Available The objective of the present study was to perform a spectral analysis of the electrical activity of the left colon of patients with hepatosplenic schistosomiasis. Thirty patients were studied, divided into 2 groups: group A was composed of 14 patients (9 males and 5 females with hepatosplenic schistosomiasis and group B was composed of 16 female patients without schistosomiasis mansoni. Three pairs of electrodes were implanted in the left colon at the moment of the surgical treatment. The signals of the electric activity of the colon were captured after postoperative recovery from the ileus and fed into a computer by means of a DATAQ data collection system which identified and captured frequencies between 0.02 and 10 Hz. Data were recorded, stored and analyzed using the WINDAQ 200 software. For electrical analysis, the average voltage of the electrical wave in the three electrodes of all patients, expressed as millivolts (mV, was considered, together with the maximum and minimum values, the root mean square (RMS, the skewness, and the results of the fast Fourier transforms. The average RMS of the schistosomiasis mansoni patients was 284.007 mV. During a long period of contraction, the RMS increased in a statistically significant manner from 127.455 mV during a resting period to 748.959 mV in patients with schistosomiasis mansoni. We conclude that there were no statistically significant differences in RMS values between patients with schistosomiasis mansoni and patients without the disease during the rest period or during a long period of contraction.
Raymond T. Damian
Full Text Available Baboons develop a syndrome, including eosinophilia and transient fever, after infection with carcariae of Schistosoma mansoni that is consistent with the human syndrome of acute schistosomiasis. Radiotelemetry can be used to follow the course of fever in infected baboons. Individual variations in intensity of disease were noted in baboons. These symptoms and signs were more closely linked to the onset of oviposition by the newly matured worms than they were to the presence of migrating schistosoma or maturing worms. The baboon is concluded to be a suitable and useful model for human acute schistosomiasis mansoni.
The rising costs of chemotherapy and synthetic molluscides have led to an increasing interest in plants which are lethal to the intermediate host of schistosomiasis (bilharzia). Over one thousand species have been tested but only a few have been phytochemically examined. Approximately fifty molluscicidal compounds have so far been isolated from plants, including saponins, terpenoids, flavonoids, naphthoquinones and tannins. The saponins from Phytolacca dodecandra are the most active and have been successfully employed in field tests. The latest results in this area and the problems involved in the use of plants and natural products for the control of schistosomiasis are discussed here.
Full Text Available BACKGROUND: The Chinese government lists advanced schistosomiasis as a leading healthcare priority due to its serious health and economic impacts, yet it has not been included in the estimates of schistosomiasis burden in the Global Burden of Disease (GBD study. Therefore, the quality of life and disability weight (DW for the advanced cases of schistosomiasis japonica have to be taken into account in the re-estimation of burden of disease due to schistosomiasis. METHODOLOGY/PRINCIPAL FINDINGS: A patient-based quality-of-life evaluation was performed for advanced schistosomiasis japonica. Suspected or officially registered advanced cases in a Schistosoma japonicum-hyperendemic county of the People's Republic of China (P.R. China were screened using a short questionnaire and physical examination. Disability and morbidity were assessed in confirmed cases, using the European quality of life questionnaire with an additional cognitive dimension (known as the "EQ-5D plus", ultrasonography, and laboratory testing. The age-specific DW of advanced schistosomiasis japonica was estimated based on patients' self-rated health scores on the visual analogue scale of the questionnaire. The relationships between health status, morbidity and DW were explored using multivariate regression models. Of 506 candidates, 215 cases were confirmed as advanced schistosomiasis japonica and evaluated. Most of the patients reported impairments in at least one health dimension, such as pain or discomfort (90.7%, usual activities (87.9%, and anxiety or depression (80.9%. The overall DW was 0.447, and age-specific DWs ranged from 0.378 among individuals aged 30-44 years to 0.510 among the elderly aged ≥ 60 years. DWs are positively associated with loss of work capacity, psychological abnormality, ascites, and active hepatitis B virus, while splenectomy and high albumin were protective factors for quality of life. CONCLUSIONS/SIGNIFICANCE: These patient-preference disability
Ekpo, Uwem F.; Hürlimann, Eveline; Schur, Nadine
Schistosomiasis prevalence data for Nigeria were extracted from peer-reviewed journals and reports, geo-referenced and collated in a nationwide geographical information system database for the generation of point prevalence maps. This exercise revealed that the disease is endemic in 35 of the cou......Schistosomiasis prevalence data for Nigeria were extracted from peer-reviewed journals and reports, geo-referenced and collated in a nationwide geographical information system database for the generation of point prevalence maps. This exercise revealed that the disease is endemic in 35...
Ernest Tambo, Jia Tei-Wu, Xiao Ning, Wei Hu, Zhou Xiao-Nong
Full Text Available Objective: Evidence-based and innovative approaches aiming to reduce or eliminate the local and global burden of schistosomiasis are urgently needed. Local elimination has proved difficult and requires vigorous political and financial commitment for prolonged long-term benefits. Yet, available literature provides limited evidence on the impact and effectiveness of different local and national schistosomiasis programs and community interventions models. Integrated schistosomiasis control interventions models in P.R. China have provided hopes that elimination can be achievable goal both endemic areas in China and African countries, where most vulnerable children population lives. Methods: The paper overviewed to what extent and impact of various implemented models and programs, and provides an understanding of the robustness of schistosomiasis control towards elimination interventions in endemic communities in P.R. China and African countries. Results: It provides vital evidence to galvanize governments and global stakeholders in upholding cost-effective interventions models and research innovations in guiding sustainable decision-making policies and priorities towards achieving global schistosomiasis elimination in China and Africa. Conclusion: Successful Chinese lessons learnt and experiences from varied schistosomiasis models integration and policies practice holds immense promise when transfer and apply within an integrated trans-disciplinary and intersectorial sectors schistosomiasis approaches in ending schistosomiasis endemicity and epidemics episodes in both P.R. China and African countries. Furthermore ensuring community engagement and participation, health education and resilience towards community projects ownership are essential in sustained national schistosomiasis elimination programmes and eventual eradication benefits. J Microbiol Infect Dis 2017; 7(2: 104-118
Rodrigo Martins Brandão
Full Text Available Strongyloides stercoralis hyperinfection syndrome is classically associated with impaired host response and implies in an overburden of larvae in its usual cycle. It has been recognized as a severe and potentially fatal condition in immunocompromised individuals, especially those using oral corticosteroids. Infection with Schistosoma mansoni not only increases the susceptibility to HIV infection, but also promotes progression to disease. The association of the most severe forms of strongyloidiasis and AIDS is scarcely described, even more when S. mansoni is also associated. The authors describe a case of a 34-year-old previously healthy male, admitted to the emergency department with a history of hematemesis associated with dyspnea, hemoptysis, and fever. He referred homosexual relations for 6 years. Physical examination showed an ill-looking patient, and was remarkable for tachycardia, tachypnea, diaphoresis, and pulse oximetry of 70% in room air. Lungs examination revealed the presence of rales in the left base. Chest radiography showed a diffuse and bilateral reticulo-nodular pattern. HIV serology was positive. Empirical antimicrobial therapy and corticosteroids were initiated. On the third day of hospitalization, petechiae appeared over the periumbilical area, but no further investigation was undertaken because the patient died soon after. The autopsy findings were compatible with S. stercoralis disseminated infection, a hepatic intestinal chronic form of schistosomiasis, and septic shock as the primary cause of death. The authors call attention to this infrequent association.
Ochodo, Eleanor A; Gopalakrishna, Gowri; Spek, Bea; Reitsma, Johannes B; van Lieshout, Lisette; Polman, Katja; Lamberton, Poppy; Bossuyt, Patrick M M; Leeflang, Mariska M G
BACKGROUND: Point-of-care (POC) tests for diagnosing schistosomiasis include tests based on circulating antigen detection and urine reagent strip tests. If they had sufficient diagnostic accuracy they could replace conventional microscopy as they provide a quicker answer and are easier to use.
Dam, van G.J.; Wichers, J.H.; Falcao Ferreira, T.M.; Ghati, D.; Amerongen, van A.; Deelder, A.M.
A newly developed reagent strip assay for the diagnosis of schistosomiasis based on parasite antigen detection in urine of infected individuals was evaluated. The test uses the principle of lateral flow through a nitrocellulose strip of the sample mixed with a colloidal carbon conjugate of a
Sotillo, Javier; Doolan, Denise; Loukas, Alex
Schistosomiasis is a neglected tropical disease affecting hundreds of millions of people worldwide. Recent advances in the field of proteomics and the development of new and highly sensitive mass spectrometers and quantitative techniques have provided new tools for advancing the molecular biology, cell biology, diagnosis and vaccine development for public health threats such as schistosomiasis. Areas covered: In this review we describe the latest advances in research that utilizes proteomics-based tools to address some of the key challenges to developing effective interventions against schistosomiasis. We also provide information about the potential of extracellular vesicles to advance the fight against this devastating disease. Expert commentary: Different proteins are already being tested as vaccines against schistosomiasis with promising results. The re-analysis of the Schistosoma spp. proteomes using new and more sensitive mass spectrometers as well as better separation approaches will help identify more vaccine targets in a rational and informed manner. In addition, the recent development of new proteome microarrays will facilitate characterisation of novel markers of infection as well as new vaccine and diagnostic candidate antigens.
Belkisyolé Alarcón de Noya
Full Text Available Schistosomiasis low transmission areas as Venezuela, can be defined as those where the vector exists, the prevalence of active cases is under 25%, individuals with mild intensity of infection predominate and are mostly asymptomatic. These areas are the consequence of effective control programs, however, "silent" epidemiological places are difficult to trace, avoiding the opportune diagnosis and treatment of infected persons. Clinic and abdominal ultrasound have not shown to discriminate infected from uninfected persons in areas where besides Schistosoma mansoni, intestinal parasites are the rule. Under these conditions, serology remains as a very valuable diagnostic tool, since it gives a closer approximation to the true prevalence. In this sense, circumoval precipitin test, ELISA-SEA with sodium metaperiodate, and alkaline phosphatase immunoassay joined to coprology allow the identification of the "schistosomiasis cases". In relation to public health, schistosomiasis has been underestimated by the sanitary authorities and the investment on its control is being transferred to other diseases of major social and political relevance neglecting sanitary efforts and allowing growth of snail population. Some strategies of diagnosis and control should be done before schistosomiasis reemergence occurs in low transmission areas.
Noriode, Rukeme M; Idowu, Emmanuel T; Otubanjo, Olubunmi A; Mafe, Margaret A
Urinary schistosomiasis is endemic in many rural communities of Nigeria and school aged children are mostly affected. A cross-sectional study was carried out to assess the prevalence and intensity of urinary schistosomiasis infection among 251 school aged children in two communities of Ovia South West LGA of Edo State, Nigeria, as well as their knowledge on the control/elimination measures. Urine samples were collected and examined by microscopy using filtration technique. In addition, a questionnaire survey was conducted among school-aged children and health care providers, probing their knowledge, attitude and practices on on-going control activities. The prevalence of urinary schistosomiasis among the school-aged children was 65.3%. The prevalence was generally higher among females (68.8%) and children in the age groups 10-14 (69.9%). The intensity of infection ranged from 1 to 5044 (mean=449.8) eggs/10ml of urine with a higher proportion having heavy infections (76.8%, P<0.05). Water contact was attested by 123 (49.0%) of the children; of these 123, 74 (60.1%) were infected. The children's knowledge on urinary schistosomiasis was deficient. The high prevalences reported in these communities require integrated approach to control which essentially should incorporate the provision of safe water supply and sanitary facilities, and health education in addition to the annual mass praziquantel distribution, to reduce transmission. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.
Appleton, C.C.; Ellery, W.N.; Byskov, Jens
A well documented epidemic of human intestinal schistosomiasis caused by Schistosoma mansoni occurred at Maun in the seasonal part of the Okavango Delta, Botswana, building from very few cases in the 1950s and early 1960s to a peak prevalence of >80% in the 1980s. A retrospective analysis...
Schur, Nadine; Hürlimann, Eveline; Garba, Amadou
Schistosomiasis is a water-based disease that is believed to affect over 200 million people with an estimated 97% of the infections concentrated in Africa. However, these statistics are largely based on population re-adjusted data originally published by Utroska and colleagues more than 20 years ...
Full Text Available The immune system protects the organism from foreign invaders and foreign substances and is involved in physiological functions that range from tissue repair to neurocognition. However, an excessive or dysregulated immune response can cause immunopathology and disease. A 39-year-old man was affected by severe hepatosplenic schistosomiasis mansoni and by amyotrophic lateral sclerosis. One question that arose was, whether there was a relation between the parasitic and the neurodegenerative disease. IL-17, a proinflammatory cytokine, is produced mainly by T helper-17 CD4 cells, a recently discovered new lineage of effector CD4 T cells. Experimental mouse models of schistosomiasis have shown that IL-17 is a key player in the immunopathology of schistosomiasis. There are also reports that suggest that IL-17 might have an important role in the pathogenesis of amyotrophic lateral sclerosis. It is hypothesized that the factors that might have led to increased IL-17 in the hepatosplenic schistosomiasis mansoni might also have contributed to the development of amyotrophic lateral sclerosis in the described patient. A multitude of environmental factors, including infections, xenobiotic substances, intestinal microbiota, and vitamin D deficiency, that are able to induce a proinflammatory immune response polarization, might favor the development of amyotrophic lateral sclerosis in predisposed individuals.
The work presented in this thesis is an investigation of the immune responses induced by chronic schistosomiasis in Gabonese schoolchildren. By investigating concurrently various aspects of the immune response, including innate, adaptive and regulatory responses, we are able to gain a more in-depth
Holtfreter, Martha Charlotte; Neubauer, Heinrich; Groten, Tanja; El-Adawy, Hosny; Pastuschek, Jana; Richter, Joachim; Häussinger, Dieter; Pletz, Mathias Wilhelm; Schleenvoigt, Benjamin Thomas
Schistosomiasis in pregnancy may cause low birth weight, prematurity and stillbirth of the offspring. The placenta of pregnant women might be involved when schistosome ova are trapped in placental tissue. Standard histopathological methods only allow the examination of a limited amount of placental tissue and are therefore not sufficiently sensitive. Thus, placental schistosomiasis remains underdiagnosed and its role in contributing to schistosomiasis-associated pregnancy outcomes remains unclear. Here we investigated an advanced maceration method in order to recover a maximum number of schistosome ova from the placenta. We examined the effect of different potassium hydroxide (KOH) concentrations and different tissue fixatives with respect to maceration success and egg morphology. Placental tissue was kept either in 0.9% saline, 5% formalin or 70% ethanol and was macerated together with Schistosoma mansoni infested mouse livers and KOH 4% or 10%, respectively. We found that placenta maceration using 4% KOH at 37°C for 24 h was the most effective method: placental tissue was completely digested, egg morphology was well preserved and alkaline concentration was the lowest. Ethanol proved to be the best fixative for this method. Here we propose an improved maceration technique in terms of sensitivity, safety and required skills, which may enable its wider use also in endemic areas. This technique may contribute to clarifying the role of placental involvement in pregnant women with schistosomiasis.
CARVALHO Omar S.
Full Text Available This study was conducted to assess the presence of schistosomiasis mansoni in the "Noroeste de Minas" mesoregion, an area considered non-endemic. A malacologic survey and parasitologic stool examinations were undertaken in 13 municipalities of the mesoregion. A sample of 3,283 primary school students was submitted to fecal examination by the Kato-Katz method. A total of 3,627 planorbids was collected and examined. The molluscs were identified as Biomphalaria straminea in seven municipalities (Unaí, Bonfinópolis de Minas, Paracatu, João Pinheiro, Vazante, Lagamar and Lagoa Grande and as Biomphalaria peregrina in one (Presidente Olegário. All planorbids were negative for Schistosoma mansoni. Four students were diagnosed with schistosomiasis in the municipalities of Buritis, Formoso, Paracatu and Unaí, but none of these cases was considered autochthonous. The data obtained indicate that the "Noroeste de Minas" mesoregion continues to be non-endemic for schistosomiasis mansoni, although the presence of intermediate hosts associated with parasitized individuals emphasizes the need for epidemiological surveillance of schistosomiasis in this mesoregion.
Grimes, Jack E T; Croll, David; Harrison, Wendy E; Utzinger, Jürg; Freeman, Matthew C; Templeton, Michael R
Schistosomiasis is a disease caused by infection with blood flukes of the genus Schistosoma. Transmission of, and exposure to, the parasite result from faecal or urinary contamination of freshwater containing intermediate host snails, and dermal contact with the same water. The World Health Assembly resolution 65.21 from May 2012 urges member states to eliminate schistosomiasis through preventive chemotherapy (i.e. periodic large-scale administration of the antischistosomal drug praziquantel to school-aged children and other high-risk groups), provision of water, sanitation and hygiene (WASH) and snail control. However, control measures focus almost exclusively on preventive chemotherapy, while only few studies made an attempt to determine the impact of upgraded access to safe water, adequate sanitation and good hygiene on schistosome transmission. We recently completed a systematic review and meta-analysis pertaining to WASH and schistosomiasis and found that people with safe water and adequate sanitation have significantly lower odds of a Schistosoma infection. Importantly though, the transmission of schistosomiasis is deeply entrenched in social-ecological systems, and hence is governed by setting-specific cultural and environmental factors that determine human behaviour and snail populations. Here, we provide a comprehensive review of the literature, which explores the transmission routes of schistosomes, particularly focussing on how these might be disrupted with WASH-related technologies and human behaviour. Additionally, future research directions in this area are highlighted.
Monde, C.; Syampungani, S.; Brink, van den P.J.
A number of human disease prevalences are supported by host-parasite-environment interactions. One such disease is schistosomiasis. Schistosoma parasites are transmitted between the snail intermediate hosts and mammalian definitive hosts in an aquatic environment. This host-environment link
Bustinduy, Amaya L; Luzinda, Kenneth; Mpoya, Simon; Gothard, Philip; Stone, Neil; Wright, Stephen; Stothard, J Russell
An association between late-stage hepatosplenic schistosomiasis and endomyocardial fibrosis (EMF) has been suggested but not proven. We present the case of a 12-year-old Ugandan boy with striking comorbidities, including advanced periportal fibrosis caused by Schistosoma mansoni infection and right ventricular EMF, and discuss the possible correlation between both diseases. © The American Society of Tropical Medicine and Hygiene.
Erikstrup, Christian; Kallestrup, Per; Zinyama-Gutsire, Rutendo B L
We previously reported that treatment for schistosomiasis in persons infected with human immunodeficiency virus 1 (HIV-1) attenuated HIV replication as measured by plasma HIV RNA. We investigated systemic inflammation as measured by plasma levels of soluble tumor necrosis factor-alpha receptor II...
Ying, Zhao-yu; Tan, Xiao-dong; Gao, Xu-dong; Ni, Zi-ling; Liu, Bei
To assess the impact of the "Oriental Star shipwreck event" on the risk of schistosomiasis transmission in Jianli County, Hubei Province, so as to provide the evidence for formulating appropriate measures of schistosomiasis prevention and control. Based on the field observation and investigation, the data of the on-the-spot rescue and the historical endemic situation of schistosomiasis in Jianli County were collected and analyzed. Meanwhile, the focus group discussion and risk matrix were conducted to assess the risk of schistosome infection of the rescuers. Over 10 000 rescuers participated in the search operation, including the armed police forces, local people, reservists and so on. The armed police forces were the major components, which accounted for 39%. Jianli country was schistosomiasis endemic area with a high infection level in history, but the endemic situation had been mitigated significantly after years of positive prevention and treatment; the schistosome infection rate of population was 0.44% in 2014 and the Oncomelania hupensis snail area was only 6.6 hm2 around the rescue areas in the upstream and downstream. In addition, the snail density was not high, and no infected snails had been found for 11 years. The risk of schistosome infection was in the medium level. Though there exists the schistosome infection risk in the water area where the accident happened, the probability of occurrence is not high. In order to prevent the outbreak and endemic of schistosomiasis, the protection measures and health education to the rescuers as well as snail control and monitoring, and early-warning should be strengthened.
Zhang, Yun; Feng, Xi-guang; Wu, Ming-shou; Xiong, Meng-tao; Shen, Mei-fen; Sun, Jia-yu
To evaluate the effect of comprehensive schistosomiasis control project in Yunnan Province after its implementation for ten years, so as to provide the evidence for formulating the future prevention and control strategy. The data of the schistosomiasis comprehensive control project and the endemic situation were collected and analyzed to evaluate the control effect of the project in Yunnan Province from 2004 to 2013. After the comprehensive control project implementation for ten years, the Oncomelania hupensis snail area in Yunnan Province decreased from 4,364.79 hm2 in 2004 to 1,528.50 hm2 in 2013, with a reduction rate of 64.98%, and the occurrence rate of frames with snails and the density of living snails decreased from 4.71% and 0.26 snails/0.1 m2 in 2004 to 1.35% and 0.04 snails/0.1 m2 in 2013, with the reduction rates of 71.34% and 84.62%, respectively. The schistosome infected snails were found only in 2011 and 2013 since 2008. In 2013, the infection rates of human (0.0021%) and cattle (0.0209%) decreased by 99.84% and 99.44%, respectively, compared to those in 2004, and no acute schistosome infection cases were found since 2008. The 212 villages with relatively serious endemic situation (Type One, Type Two and Type Three) all declined to the slight endemic villages (Type Four and Type Five), therefore, they reached the criteria of schistosomiasis transmission controlled or interrupted. The awareness rates of schistosomiasis control among villagers and students in endemic areas were above 90% and 98%, respectively. The effect of the comprehensive schistosomiasis control project is significant in Yunnan Province, but the task to consolidate and enlarge the control results still remains a challenge.
James J Cody
Full Text Available Schistosomiasis remains a health burden in many parts of the world. The complex life cycle of Schistosoma parasites and the economic and societal conditions present in endemic areas make the prospect of eradication unlikely in the foreseeable future. Continued and vigorous research efforts must therefore be directed at this disease, particularly since only a single World Health Organization (WHO-approved drug is available for treatment. The National Institutes of Health (NIH-National Institute of Allergy and Infectious Diseases (NIAID Schistosomiasis Resource Center (SRC at the Biomedical Research Institute provides investigators with the critical raw materials needed to carry out this important research. The SRC makes available, free of charge (including international shipping costs, not only infected host organisms but also a wide array of molecular reagents derived from all life stages of each of the three main human schistosome parasites. As the field of schistosomiasis research rapidly advances, it is likely to become increasingly reliant on omics, transgenics, epigenetics, and microbiome-related research approaches. The SRC has and will continue to monitor and contribute to advances in the field in order to support these research efforts with an expanding array of molecular reagents. In addition to providing investigators with source materials, the SRC has expanded its educational mission by offering a molecular techniques training course and has recently organized an international schistosomiasis-focused meeting. This review provides an overview of the materials and services that are available at the SRC for schistosomiasis researchers, with a focus on updates that have occurred since the original overview in 2008.
Full Text Available Schistosomiasis is one of the neglected tropical diseases targeted for elimination in Uganda through the Mass Drug Administration (MDA programme. Praziquantel has been distributed using community resource persons in fixed sites and house-to-house visits; however the uptake is still below target coverage. In 2011/2012 MDA exercise, uptake stood at 50% yet WHO target coverage is 75% at community level. We assessed the uptake of MDA and the associated factors in Koome Islands, Central Uganda.In March 2013, we conducted a mixed methods cross sectional study in 15 randomly selected villages. We interviewed a total of 615 respondents aged 18 years and above using semi structured questionnaires and five key informants were also purposively selected. Univariate and multivariate analysis was done. MDA uptake was defined as self reported swallowing of praziquantel during the last (2012 MDA campaign. We conducted key informant interviews with Ministry of Health, district health personnel and community health workers.Self reported uptake of praziquantel was 44.7% (275/615, 95% confidence interval (CI 40.8-48.7%. Of the 275 community members who said they had swallowed praziquantel, 142 (51.6% reported that they had developed side effects. Uptake of MDA was more likely if the respondent was knowledgeable about schistosomiasis transmission and prevention (adjusted odds ratio [AOR] 1.85, 95% CI 1.22-2.81 and reported to have received health education from the health personnel (AOR 5.95, 95% CI 3.67-9.65. Service delivery challenges such as drug shortages and community health worker attrition also influenced MDA in Koome Islands.Uptake of MDA for schistosomiasis control in Koome was sub optimal. Lack of knowledge about schistosomiasis transmission and prevention, inadequate health education and drug shortages are some of the major factors associated with low uptake. These could be addressed through routine health education and systematic drug supply for the
Xu, Rui; Feng, Jintao; Hong, Yang; Lv, Chao; Zhao, Dengyun; Lin, Jiaojiao; Lu, Ke; Li, Hao; Liu, Jinming; Cao, Xiaodan; Wang, Tao; Zai, Jinli; Wang, Zhaozhe; Jia, Bingguang; Han, Qian; Zhu, Chuangang
Schistosomiasis remains a major public health concern in China and an epidemiological survey has revealed that schistosome-infected bovines and goats are the main transmission sources for the disease. Therefore, development of a sensitive technique for the diagnosis of schistosomiasis in domestic animals is necessary. A novel colloidal gold immunochromatography assay (GICA) strip was developed for detecting Schistosoma japonicum in domestic animals. The colloidal gold was conjugated with recombinant streptococcal protein G (rSPG). As the test and control lines, the schistosome soluble egg antigen and rSPG, respectively, were blotted on nitrocellulose membrane. The lowest detectable serum dilution was 1∶640 for schistosome-infected buffaloes. The cross-reaction rate of GICA was 14.29% with Paramphistomum sp. in buffaloes, 16.67% with Haemonchus sp. in goats, and 33.33% with Orientobilharzia sp. in goats. These results were slightly lower and similar to those obtained through ELISA. Moreover, the strips for detecting S. japonicum in mice, rabbits, buffaloes, and goats showed high sensitivity (100.00%, 100.00%, 100.00%, and 100.00%, respectively) and specificity (100.00%, 100.00%, 94.23%, and 88.64%, respectively). And the sensitivity or specificity of the GICA strips did not present any significant differences after storage for 12 months at room temperature. When compared with ELISA, the GICA strips exhibited similar sensitivity and specificity in the diagnosis of schistosomiasis in mice, rabbits, buffaloes, and goats. Besides, only 5 μl of serum are required for the test and the detection can be completed within 5 min. This study is the first to develop a GICA strip using gold-rSPG conjugate for the diagnosing of schistosomiasis in domestic animals, and preliminary results showed that the developed strip may be suitable for large-scale screening of schistosomiasis in endemic areas.
Luiz Arthur Calheiros Leite
Full Text Available BACKGROUND Schistosomiasis is a tropical disease. Patients who develop hepatosplenic schistosomiasis have clinical findings including periportal fibrosis, portal hypertension, cytopenia, splenomegaly and gastrointestinal hemorrhage. OBJECTIVE The aim of this study was to analyze the hemostatic and hematologic findings of patients with schistosomiasis and correlate these to the size of the spleen. METHODS Fifty-five adults with hepatosplenic schistosomiasis and 30 healthy subjects were selected through a history of contact with contaminated water, physical examination and ultrasound characteristics such as periportal fibrosis and splenomegaly in the Gastroenterology Service of the Universidade Federal de Pernambuco. Blood samples were collected to determine liver function, blood counts, prothrombin (international normalized ratio, partial thromboplastin time and fibrinogen and D-Dimer levels using the Pentra 120 hematological analyzer (HORIBA/ABX, Density Plus (test photo-optical Trinity Biotech, Ireland and COBAS analyzer 6000 (Roche. Furthermore, the longitudinal size of the spleen was measured by ultrasound (Acuson X analyzer 150, Siemens. The Student t-test, the Fisher test and Pearson's correlation were used to analyze the results with statistical significance being set for a p-value < 0.05. RESULTS The mean age was higher for the Study Group than for the Control Group (54 ± 13.9 vs. 38 ± 12.7 years. The average longitudinal diameter of the spleen was 16.9 cm (Range: 12.3-26.3 cm. Anemia is a common finding in patients with schistosomiasis (36.3%. The mean platelet and leukocyte counts of patients were lower than for the Control Group (p-value < 0.001. Moreover, the international normalized ratio (1.42 vs. 1.04, partial thromboplastin time (37.9 vs. 30.5 seconds and D-Dimer concentration (393 vs. 86.5 ng/mL were higher for the Study Group compared to the Control Group. CONCLUSION This study suggests that hematological and hemostatic
Full Text Available The Centre de Recherche sur les Méningites et les Schistosomes (CERMES is a research institute depending on the Organisation de Coordination et de Coopération pour la lutte contre les Grandes Endémies - a West African Organization for Public Health - devoted to the studies on schistosomiasis and meningitis. The staff includes 32 persons with 11 scientists and one financial officer. The activities of the CERMES involving schistosomiasis concern three research units: (a ecology of human and animal schistosomiasis transmission; the CERMES defined the different patterns of schistosomiasis transmission in Niger (involving African dry savana; in this field, we have shown, (i the existence of important variability in conditions of transmission of S. haematobium and, (ii natural hybridization between parasitic species of the ruminants (S. bovis and S. curassoni and genetic interaction between human and animal parasites; (b definition of morbidity indicators usable for rapid assessment methods, for appraisal of the severity of the disease and for the evaluation of the efficiency of control methods; we have established the correlation between ultrasonographic data and some cheap and simple field indicators; (c immune response and protective immunity induced by recombinant glutathion S-transferase (Sm28, Sb28 and Sh28 in homologous and heterologous animal models including goats, sheep and non human primates (Erythrocebus patas. In Niger, we participate in all control programs against schistosomiasis to define control strategies, to supervise operations and to participate in their evaluation with external experts. International collaborations constitute a frame including four laboratories in Africa and six laboratories in developed countries (Europe and USA
Horacio Manuel Santana Teles
Full Text Available The purpose of our study in the municipality of Bananal, state of São Paulo, Brazil, was to stop the transmission of schistosomiasis mansoni. Particular emphasis was given to such items as the active surveillance and eventual treatment of hosts, mapping parasite foci, and increasing the extent of basic sanitation in the municipality. Now, our records indicate that the eradication of schistosomiasis in the municipality of Bananal is attainable. However, as the vector Biomphalaria tenagophila can still be found in some water bodies within this municipality, it remains included in the area where schistosomiasis is endemic, which calls for very strict measures to avoid the human cases of schistososomiasis. The expansion of the coverage of the basic sanitation network and treatment of Schistosoma mansoni cases diagnosed during periodic surveys are part of the plans to eradicate schistosomiasis in Bananal.
Han Xiao; Shiyue Li; Xinguang Chen; Bin Yu; Mengting Gao; Hong Yan; Chukwuemeka N Okafor
Background Among millions of people who suffer from schistosomiasis in China, adolescents are at increased risk to be infected. However, there is a lack of theory-guided behavioral prevention intervention programs to protect these adolescents. This study attempted to apply the Protection Motivation Theory (PMT) in predicting intentions to engage in protective behaviors against schistosomiasis infection. Methods The participants were selected using the stratified cluster sampling method. Surve...
Al Nagdy, Sohair A. [سهير علي النجدي; Saoud, M. F. A.; Morcos, N. Y. S.
Schistosomiasis is mostly widespread in communities suffering from protein energy malnutrition. The development of an animal model for each condition is required for better understanding of changes in certain biochemical indices in pure schistosomiasis or pure energy malnutrition or both. Measurements of some enzymes as well as trace elements have been found to be valuable as diagnostic and prognostic indicators for tissue destruction. Accordingly, the present investigation reports measuremen...
Zhang, Jing; Li, Zhao-jun; Qiu, Ling; Li, Dong; Chen, Jun-jiang; Xie, Hua; Liu, Yue-min; Hu, Fei; Yuan, Min; Lin, Dan-dan
To design and develop new types of health education materials which are suitable for fishermen and boatmen in endemic areas of marshland and lake regions, and to observe their application effects. A total of 292 adult fishmen and boatmen who lived in Houshan Village, Yugan County, the schistosomiasis endemic area of Poyang Lake Region, were selected randomly and investigated by questionnaires to understand the status of their knowledge, attitudes, practices on schistosomiasis control as well as the channels for getting information on schistosomiasis control and the materials that they were willing to accept. Then the information and materials suitable for the target population were developed together by the researchers and the volunteers of the villagers through focus group discussions, personal interviews and the Delphi method. A series of participatory health education materials of schistosomiasis control targeted to the fishmen and boatmen were developed, including 2 live posters, 2 picture puzzles, 2 short opusculums and one song about schistosomiasis control. The field application showed that 98.97%, 84.38%, 78.35% and 80.93% of the participants considered those materials had scientificity, intelligibility, interestingness and practicability, respectively. The participatory health education materials of schistosomiasis control is suitable for fishmen and boatmen, which can be used for reference by other endemic areas in marshland and lake regions.
Liu, Han-cheng; Zhong, Chen-hui; Liao, Si-qi; He, Hui
To investigate the current situation of management of institutions of schistosomiasis prevention and control in Hubei Province, so as to explore the probable competency building standards for these institutions at the county and township levels. By using a combination of quantitative and qualitative methods, the institutions of schistosomiasis prevention and control at county and township levels were investigated for the institutional setup, staffing and fulfillment functions since the reform of 2004. Among 63 schistosomiasis endemic counties (cities, districts) of Hubei Province, there were 26 independent schistosomiasis control institutions (41.27%), there were 24 institutions which were incorporated into CDC (38.10%), and there were no institutions in 13 counties (20.63%). Among 518 endemic towns, there were 299 institutions (57.72%). The total staffing size were 1 932, but there were 1 586 (82.09%) people actually working in the post, and therefore there were 346 (17.91%) empty positions. The average rates of carrying out the six functions were 91.48%-71.19%, but only 19.23% of the institutions participated in the comprehensive schistosomiasis control management project and its effect assessment. According to the management model for schistosomiasis control institutions under the current institutional mechanisms, we need a rigorous industry standard to constrain, guide and standardize the management and capacity-building of the institutions in different historical periods.
Zhu, Huai-Min; Xiang, Shuo; Yang, Kun; Wu, Xiao-Hua; Zhou, Xiao-Nong
Large-scale hydroprojects have a propensity for incurring schistosomiasis epidemics by altering the environments of their vicinities. As the construction of the Three Gorges Dam, one of the world's largest hydroprojects to date, draws near its conclusion, an assessment of the dam's capacity in causing schistosomiasis becomes more urgent and pressing. This article reviews recent investigations into the possible effects of the dam on schistosomiasis in the Three Gorges region and areas along the Yangtze downstream from the dam. Data used in this article were extracted from peer-reviewed papers found in PubMed, Chinese Journal of Parasitology and Parasitic Diseases, and Chinese Journal of Schistosomiasis Control. Results indicate that the Three Gorges Dam is capable of inducing a wide variety of environmental and ecological changes both within the Three Gorges region and in downstream areas. These changes, however, carry ambivalent implications for the reproduction of Oncomelania snails and the spreading of schistosome infections. Furthermore, major changes in the demographics and agricultural practices of the Three Gorges and downstream Yangtze areas caused by the dam could also exert significant influence on the transmission of schistosomiasis in these regions. Major conclusions of this review include the need for further ecological simulations of the Three Gorges Dam and the need for deploying monitoring and intervention systems to provide successful prophylaxis of the Three Gorges Dam-associated schistosomiasis emergence.
Donald P McManus
Full Text Available Schistosomiasis is a chronic and debilitating parasitic disease that has often been neglected because it is a disease of poverty, affecting poor rural communities in the developing world. This is not the case in the People's Republic of China (PRC, where the disease, caused by Schistosoma japonicum, has long captured the attention of the Chinese authorities who have, over the past 50-60 years, undertaken remarkably successful control programs that have substantially reduced the schistosomiasis disease burden. The Dongting Lake region in Hunan province is one of the major schistosome-endemic areas in the PRC due to its vast marshland habitats for the Oncomelania snail intermediate hosts of S. japonicum. Along with social, demographic, and other environmental factors, the recent completion and closure of the Three Gorges dam will most likely increase the range of these snail habitats, with the potential for re-emergence of schistosomiasis and increased transmission in Hunan and other schistosome-endemic provinces being a particular concern. In this paper, we review the history and the current status of schistosomiasis control in the Dongting Lake region. We explore the epidemiological factors contributing to S. japonicum transmission there, and summarise some of the key research findings from studies undertaken on schistosomiasis in Hunan province over the past 10 years. The impact of this research on current and future approaches for sustainable integrated control of schistosomiasis in this and other endemic areas in the PRC is emphasised.
Faria, Andreia Vasconcelos; Cerqueira, Elza Maria Figueiras Pedreira de; Reis, Fabiano; Menezes Neto, Jose Ribeiro; Zanardi, Veronica de Araujo [Universidade Estadual de Campinas, SP (Brazil). Faculdade de Ciencias Medicas. Dept. de Radiologia]. E-mail: firstname.lastname@example.org; Pirani, Clodoaldo; Damasceno, Benito Pereira [Universidade Estadual de Campinas, SP (Brazil). Faculdade de Ciencias Medicas. Dept. de Neurologia
We report four cases of patients with schistosomiasis in the central nervous system and describe and correlate the radiologic findings with clinical manifestations. In one patient, cerebral involvement presented as a pseudotumoral lesion confirmed by autopsy. Three other patients had schistosomiasis in the spinal cord characterized by an intramedullary mass and radicular and leptomeningeal enhancement after administration of gadolinium. Our findings show the importance of considering schistosomiasis in the differential diagnosis of intramedullary or cerebral lesions in patients of endemic areas of schistosomiasis. (author)
Full Text Available Seventy patients with hepatosplenic schistosomiasis were treated with oxamniquine. The patients lived iti an endemic area and were evaluated 6, 18 and 24 months after treatment, during which time transmission in the area was interrupted. After treatment, clinical improvement occurred in 49 (70% of the patients, as seen by reduction in visceromegaly and reversion of liver nodules. Reversion of hepatosplenic disease occurred in 28 (40% patients and in liver nodularity in 26 (47.3%patients after 24 months. Reversion of hepatosplenic disease was seen in 12 (21% patients and liver nodules disappeared in 4 (8.5% as early as 6 months after treatment. In general, hepatosplenomegaly reverses earlier than liver nodularity. Itis notable that reversion of hepatosplenic disease occurred in many individuals with a history ofprevious treatment and also in some with advanced age. In four cases this clinical form of the disease had existed for 20 years. Therefore, there must exist factors other than age and duration of the condition which determine the reversibility of this clinical form. Ourresults reinforce the concept that, in patients with hepatosplenic disease without esophageal hemorrhages, specific treatment shouldpreceed surgical intervention even in those with a history of previous treatment. At least 18 months should be allowed for the ejfects of treatment to be manifest.Foram tratados com oxamniquine 70 esquistossomóticos, com a forma hepatosplênica. Os pacientes permaneceram na área endêmica e foram avaliados clinicamente antes, 6, 18, e 24 meses após o tratamento. Durante este período a transmissão foi interrompida na área. Após o tratamento específico ocorreu melhora clínica em 49(70% pacientes, traduzida por diminuição nas visceromegalias e reversão do fígado nodular. Houve reversão da forma hepatosplênica em 28(40% e do fígado nodular em 26(47.3% após 24 meses. A reversão da forma hepatosplênica já havia ocorrido após seis
Braae, Uffe Christian; Saarnak, Christopher; Mukaratirwa, Samson
BACKGROUND: This study aimed to map the distribution of Taenia solium taeniosis/cysticercosis and the co-distribution with schistosomiasis in Africa. These two major neglected tropical diseases are presumed to be widely distributed in Africa, but currently the level of co-distribution is unclear...... to combine the epidemiological data on the apparent prevalence with external information on test characteristics to estimate informed district-level prevalence of taeniosis and porcine cysticercosis. Districts with T. solium taeniosis/cysticercosis presence were cross-referenced with the Global Neglected...... countries identified from OIE reports. All 31 countries were considered, on national scale, to have co-distribution with schistosomiasis. Presence of both parasites was confirmed in 124 districts in 17 countries. The informed prevalence of taeniosis and porcine cysticercosis were estimated for 14 and 41...
Nyakundi, Ruth K; Nyamongo, Onkoba; Maamun, Jeneby
models. To examine this interaction, we conducted a randomized controlled study using the baboon (Papio anubis) to analyze the effect of chronic schistosomiasis on severe malaria. Two groups of baboons (n = 8 each) and a schistosomiasis control group (n = 3) were infected with 500 Schistosoma mansoni...... malaria. A total of 81% of baboons exposed to chronic S. mansoni infection with or without praziquantel treatment survived malaria, compared to only 25% of animals infected with P. knowlesi only (P = 0.01). Schistosome-infected animals also had significantly lower parasite burdens (P = 0.004) than...... the baboons in the P. knowlesi-only group and were protected from severe anemia. Coinfection was associated with increased spontaneous production of interleukin-6 (IL-6), suggesting an enhanced innate immune response, whereas animals infected with P. knowlesi alone failed to develop mitogen-driven tumor...
Verônica Santos Barbosa
Full Text Available Abstract: INTRODUCTION : The expansion of schistosomiasis to previously unaffected areas is being monitored by identifying new cases and georeferencing outbreaks of vector snails. METHODS : In 2014, the Laboratório de Esquistossomose began an epidemiological survey in Serrambi and registered 2,574 people living there. RESULTS : Of these subjects, 1,414 (54.9% underwent feces examination and 63 (4.5% were diagnosed with Schistosoma mansoni infection. At this locality, seven breeding sites each were identified for Biomphalaria straminea and Biomphalaria glabrata. At two sites, B. glabrata were shedding cercariae. CONCLUSIONS : Implementing preventive measures is necessary to avoid the establishment of schistosomiasis in yet another tourist locality, Pernambuco.
Katz, N; Peixoto, S V
The number of carriers of Schistosoma mansoni infection in Brazil was estimated based on the results of parasitological examinations of feces carried out by the Fundação Nacional de Saúde (FNS - National Health Foundation) in 1996 and 1997, as well as population data from 18 states collected by the Instituto Brasileiro de Geografia e Estatística (IBGE - Brazilian Institute of Geography and Statistics). This information allowed the number of carriers of schistosomiasis mansoni to be estimated at 7.1 million in 1996 and 6. 3 million in 1997. These figures may not reflect the true situation since the population sample used was not originally selected for this purpose. The absence of precise data indicates the need for an adequate national survey of the prevalence of schistosomiasis, which continues to be an important endemic parasitic disease, justifying greater efforts for its control in Brazil.
Hesham R. El-Seedi
Full Text Available Bioassay-guided isolation using an in vitro assay testing for anti- schistosomiasis yielded a novel triterpene saponin, asparagalin A, from the n-butanol extract of the roots of Asparagus stipularis Forssk., Asparagaceae. The structure was elucidated by spectroscopic analysis and chemical transformations. Administration of asparagalin A resulted in a retardation of worm growth and locomotion at the first day and showed a significant activity of egg-laying suppression at 200 µg/mL concentration.
Full Text Available Aim: Bovine visceral schistosomiasis has been reported as an important disease entity as it affects animal health, productivity, causes economic losses due to liver condemnation, and produces a high morbidity. This study was conducted to standardize an easy, reliable dot-enzyme-linked immmunosorbent assay (ELISA for the diagnosis of visceral schistosomiasis caused by Schistosoma spindale and to know the prevalence rate in and around Hyderabad. Materials and Methods: A dot-ELISA was standardized in the laboratory using whole worm antigen (WWA and excretory-secretory antigen (ESA of S. spindale. The standardized test was used for the diagnosis of bovine visceral schistosomiasis at field level. The sensitivity and specificity of the test was compared with counter current immunoelectrophoresis. In total, 288 sera (125 cattle and 163 buffalo were screened by dot-ELISA. Results: The dot-ELISA detected 32.63% of infection (94/288 using WWA and 40.62% of infection (117/288 using ESA. In cattle, the prevalence rate was 32.80% (41/125 using WWA and 40.80% (51/125 of infection. Similarly, in buffaloes, the prevalence rate was 32.51% (53/163 using WWA and 40.49% (66/163 of infection using ESA. The overall sensitivity of dot-ELISA was 76.74% and 80.48% with WWA and ESA, respectively, and specificity was 73.3% and 78.57% in WWA and ESA, respectively. Conclusion: As ante-mortem diagnosis of visceral schistosomiasis is difficult in subclinical conditions, dot-ELISA can be used as a reliable immunodiagnostic test for diagnosis at field level.
Sudhakar, Kommu; Murthy, G S Sreenivasa; Rajeshwari, Gaddam
Bovine visceral schistosomiasis has been reported as an important disease entity as it affects animal health, productivity, causes economic losses due to liver condemnation, and produces a high morbidity. This study was conducted to standardize an easy, reliable dot-enzyme-linked immmunosorbent assay (ELISA) for the diagnosis of visceral schistosomiasis caused by Schistosoma spindale and to know the prevalence rate in and around Hyderabad. A dot-ELISA was standardized in the laboratory using whole worm antigen (WWA) and excretory-secretory antigen (ESA) of S. spindale. The standardized test was used for the diagnosis of bovine visceral schistosomiasis at field level. The sensitivity and specificity of the test was compared with counter current immunoelectrophoresis. In total, 288 sera (125 cattle and 163 buffalo) were screened by dot-ELISA. The dot-ELISA detected 32.63% of infection (94/288) using WWA and 40.62% of infection (117/288) using ESA. In cattle, the prevalence rate was 32.80% (41/125) using WWA and 40.80% (51/125) of infection. Similarly, in buffaloes, the prevalence rate was 32.51% (53/163) using WWA and 40.49% (66/163) of infection using ESA. The overall sensitivity of dot-ELISA was 76.74% and 80.48% with WWA and ESA, respectively, and specificity was 73.3% and 78.57% in WWA and ESA, respectively. As ante-mortem diagnosis of visceral schistosomiasis is difficult in subclinical conditions, dot-ELISA can be used as a reliable immunodiagnostic test for diagnosis at field level.
Richard E Sanya
Full Text Available Praziquantel-based mass treatment is the main approach to controlling schistosomiasis mansoni in endemic areas. Interventions such as provision and use of safe water, minimising contact with infested water, disposal of stool in latrines and snail control provide key avenues to break the transmission cycle and can sustain the benefits of mass treatment in the long term. Efforts are also being made to develop a schistosomiasis vaccine which, if effective, might reduce the incidence of re-infection after treatment. However, any interventions deployed need to be acceptable to, and sustainable by, the target communities.In this qualitative study, we investigated the perceptions of six Lake Victoria island communities of Koome, Uganda, about interventions to control Schistosoma mansoni infection and their willingness to participate in Schistosoma vaccine trials. Thirty-two in-depth interviews, 12 key informant interviews and 10 focus group discussions were conducted. Data were analysed using a thematic content approach.Intestinal schistosomiasis was not regarded as a serious health problem because a mass treatment programme is in place. However, the communities lack safe water sources and latrines. Mass treatment with praziquantel, safe water supplies and use of toilets were deemed the most acceptable interventions by the participants. The communities are willing to participate in Schistosoma vaccine trials.Knowledge of a community's perception about interventions to control schistosomiasis can be valuable to policy makers and programme implementers intending to set up interventions co-managed by the community members. In this study, the views of the Lake Victoria island communities of Koome are presented. This study also provides data to guide further work on alternative interventions such as Schistosoma vaccine trials in these communities.
Full Text Available Urogenital schistosomiasis, chronic infection by Schistosoma haematobium, affects 112 million people worldwide. S. haematobium worm oviposition in the bladder wall leads to granulomatous inflammation, fibrosis, and egg expulsion into the urine. Despite the global impact of urogenital schistosomiasis, basic understanding of the associated pathologic mechanisms has been incomplete due to the lack of suitable animal models. We leveraged our recently developed mouse model of urogenital schistosomiasis to perform the first-ever profiling of the early molecular events that occur in the bladder in response to the introduction of S. haematobium eggs. Microarray analysis of bladders revealed rapid, differential transcription of large numbers of genes, peaking three weeks post-egg administration. Many differentially transcribed genes were related to the canonical Type 2 anti-schistosomal immune response, as reflected by the development of egg-based bladder granulomata. Numerous collagen and metalloproteinase genes were differentially transcribed over time, revealing complex remodeling and fibrosis of the bladder that was confirmed by Masson's Trichrome staining. Multiple genes implicated in carcinogenesis pathways, including vascular endothelial growth factor-, oncogene-, and mammary tumor-related genes, were differentially transcribed in egg-injected bladders. Surprisingly, junctional adhesion molecule, claudin and uroplakin genes, key components for maintaining the urothelial barrier, were globally suppressed after bladder exposure to eggs. This occurred in the setting of urothelial hyperplasia and egg shedding in urine. Thus, S. haematobium egg expulsion is associated with intricate modulation of the urothelial barrier on the cellular and molecular level. Taken together, our findings have important implications for understanding host-parasite interactions and carcinogenesis in urogenital schistosomiasis, and may provide clues for novel therapeutic
Full Text Available Abstract Background Schistosomiasis japonica (schistosomiasis is a zoonosis that can seriously affect human health. At present, the immunodiagnostic assays for schistosomiasis detection are time-consuming and require well-trained personnel and special instruments, which can limit their use in the field. Thus, there is a pressing need for a simple and rapid immunoassay to screen patients on a large scale. In this study, we developed a novel rapid dipstick with latex immunochromatographic assay (DLIA to detect anti-Schisaosoma japonicum antibodies in human serum. Results Using latex microspheres as a color probe, DLIA was established to test standard positive and negative sera, in comparison with the classical enzyme-linked immunosorbent assay (ELISA. The sensitivity and specificity of DLIA were 95.10% (97/102 and 94.91% (261/275, respectively. The cross-reaction rates with clonorchiosis, intestinal nematodes, Angiostrongylus cantonensis and paragonimiasis were 0, 0, 0 and 42.11% respectively. All the results showed no significant difference to the ELISA. In field tests, 333 human serum samples from an endemic area were tested with DLIA, and compared with ELISA and Kato-Katz method. There was no significant difference between DLIA and ELISA on positive and negative rates of detection; however, significant differences existed between DLIA and Kato-Katz method, and between ELISA and Kato-Katz method. The kappa value between DLIA and ELISA was 0.90. Conclusions This is the first study in which DLIA was used to detect anti-Schistosoma japonicum antibody. The results show that DLIA is a simple, rapid, convenient, sensitive and specific assay for the diagnosis of schistosomiasis and is therefore very suitable for large-scale field applications and clinical detection.
Full Text Available Schistosomiasis is the third most devastating tropical disease worldwide caused by blood flukes of the genus Schistosoma. This parasitic disease is due to immunologic reactions to Schistosoma eggs trapped in tissues. Egg-released antigens stimulate tissue-destructive inflammatory and granulomatous reactions, involving different immune cell populations, including T cells and granulocytes. Granulomas lead to collagen fibers deposition and fibrosis, resulting in organ damage. Praziquantel (PZQ is the drug of choice for treating all species of schistosomes. However, PZQ kills only adult Schistosoma worms, not immature stages. The inability of PZQ to abort early infection or prevent re-infection, and the lack of prophylactic effect prompt the need for novel drugs and strategies for the prevention of schistosomiasis.Using in vitro and in vivo approaches, we have found that the alkylphospholipid analog edelfosine kills schistosomula, and displays anti-inflammatory activity. The combined treatment of PZQ and edelfosine during a few days before and after cercariae infection in a schistosomiasis mouse model, simulating a prophylactic treatment, led to seven major effects: a killing of Schistosoma parasites at early and late development stages; b reduction of hepatomegaly; c granuloma size reduction; d down-regulation of Th1, Th2 and Th17 responses at late post-infection times, thus inhibiting granuloma formation; e upregulation of IL-10 at early post-infection times, thus potentiating anti-inflammatory actions; f down-regulation of IL-10 at late post-infection times, thus favoring resistance to re-infection; g reduction in the number of blood granulocytes in late post-infection times as compared to infected untreated animals.Taken together, these data suggest that the combined treatment of PZQ and edelfosine promotes a high decrease in granuloma formation, as well as in the cellular immune response that underlies granuloma development, with changes in the
Verônica Santos Barbosa
Full Text Available INTRODUCTION: The prevalence and intensity of geohelminth infections and schistosomiasis remain high in the rural areas of Zona da Mata, Pernambuco (ZMP, Brazil, where these parasites still represent a significant public health problem. The present study aimed to spatially assess the occurrences of schistosomiasis and geohelminthiasis in the ZMP. METHODS: The ZMP has a population of 1,132,544 inhabitants, formed by 43 municipalities. An ecological study was conducted, using secondary data relating to positive human cases and parasite loads of schistosomiasis and positive human cases of geohelminthiasis that were worked up in Excel 2007. We used the coordinates of the municipal headquarters to represent the cities which served as the unit of analysis of this study. The Kernel estimator was used to spatially analyze the data and identify distribution patterns and case densities, with analysis done in ArcGIS software. RESULTS: Spatial analysis from the Kernel intensity estimator made it possible to construct density maps showing that the northern ZMP was the region with the greatest number of children infected with parasites and the populations most intensely infected by Schistosoma mansoni. In relation to geohelminths, there was higher spatial distribution of cases of Ascaris lumbricoides and Trichuris trichiura in the southern ZMP, and greater occurrence of hookworms in the northern/central ZMP. CONCLUSIONS: Despite several surveys and studies showing occurrences of schistosomiasis and geohelminthiasis in the ZMP, no preventive measures that are known to have been effective in decreasing these health hazards have yet been implemented in the endemic area.
Sokolow, Susanne H; Jones, Isabel J; Jocque, Merlijn; La, Diana; Cords, Olivia; Knight, Anika; Lund, Andrea; Wood, Chelsea L; Lafferty, Kevin D; Hoover, Christopher M; Collender, Phillip A; Remais, Justin V; Lopez-Carr, David; Fisk, Jonathan; Kuris, Armand M; De Leo, Giulio A
Dams have long been associated with elevated burdens of human schistosomiasis, but how dams increase disease is not always clear, in part because dams have many ecological and socio-economic effects. A recent hypothesis argues that dams block reproduction of the migratory river prawns that eat the snail hosts of schistosomiasis. In the Senegal River Basin, there is evidence that prawn populations declined and schistosomiasis increased after completion of the Diama Dam. Restoring prawns to a water-access site upstream of the dam reduced snail density and reinfection rates in people. However, whether a similar cascade of effects (from dams to prawns to snails to human schistosomiasis) occurs elsewhere is unknown. Here, we examine large dams worldwide and identify where their catchments intersect with endemic schistosomiasis and the historical habitat ranges of large, migratory Macrobrachium spp. prawns. River prawn habitats are widespread, and we estimate that 277-385 million people live within schistosomiasis-endemic regions where river prawns are or were present (out of the 800 million people who are at risk of schistosomiasis). Using a published repository of schistosomiasis studies in sub-Saharan Africa, we compared infection before and after the construction of 14 large dams for people living in: (i) upstream catchments within historical habitats of native prawns, (ii) comparable undammed watersheds, and (iii) dammed catchments beyond the historical reach of migratory prawns. Damming was followed by greater increases in schistosomiasis within prawn habitats than outside prawn habitats. We estimate that one third to one half of the global population-at-risk of schistosomiasis could benefit from restoration of native prawns. Because dams block prawn migrations, our results suggest that prawn extirpation contributes to the sharp increase of schistosomiasis after damming, and points to prawn restoration as an ecological solution for reducing human disease
Sokolow, S. H.; Jones, I. J.; La, D.; Cords, O.; Knight, A.; Lund, A.; Wood, C. L.; Lafferty, K. D.; Kuris, A. M.; Hoover, C.; Collender, P. A.; Remais, J.; Lopez-Carr, D.; De Leo, G.
Dams have long been associated with elevated burdens of human schistosomiasis, but how dams increase disease is not always clear, in part because dams have many ecological and socioeconomic effects. A recent hypothesis argues that dams block reproduction of the migratory river prawns that eat the snail hosts of schistosomiasis. In the Senegal River Basin, there is evidence that prawn populations declined and schistosomiasis increased after completion of the Diama Dam. Restoring prawns to a water-access site upstream of the dam reduced snail density and reinfection rates in people. However, whether a similar cascade of effects (from dams to prawns to snails to human schistosomiasis) occurs elsewhere is unknown. Here, we examine large dams worldwide and identify where their catchments intersect with endemic schistosomiasis and the historical habitat ranges of large, migratory Macrobrachium spp. prawns. River prawn habitats are widespread, and we estimate that 277 to 385 million people live within schistosomiasis-endemic regions where river prawns are or were present (out of the 800 million people who are at risk of schistosomiasis). Using a published repository of schistosomiasis studies in sub-Saharan Africa, we compared infection before and after the construction of 14 large dams for people living in: (1) upstream catchments within historical habitats of native prawns, (2) comparable undammed watersheds, and (3) dammed catchments beyond the historical reach of migratory prawns. Damming was followed by greater increases in schistosomiasis within prawn habitats than outside prawn habitats. We estimate that one third to one half of the global population-at-risk of schistosomiasis could benefit from restoring native prawns. Because dams block prawn migrations, our results suggest that prawn extirpation contributes to the sharp increase of schistosomiasis after damming, and points to prawn restoration as an ecological solution for reducing human disease.
Sokolow, Susanne H.; Jones, Isabel J.; Jocque, Merlijn M. T.; La, Diana; Cords, Olivia; Knight, Anika; Lund, Andrea; Wood, Chelsea L.; Lafferty, Kevin D.; Hoover, Christopher M.; Collender, Phillip A.; Remais, Justin V.; Lopez-Carr, David; Fisk, Jonathan; Kuris, Armand M.; De Leo, Giulio A.
Dams have long been associated with elevated burdens of human schistosomiasis, but how dams increase disease is not always clear, in part because dams have many ecological and socio-economic effects. A recent hypothesis argues that dams block reproduction of the migratory river prawns that eat the snail hosts of schistosomiasis. In the Senegal River Basin, there is evidence that prawn populations declined and schistosomiasis increased after completion of the Diama Dam. Restoring prawns to a water-access site upstream of the dam reduced snail density and reinfection rates in people. However, whether a similar cascade of effects (from dams to prawns to snails to human schistosomiasis) occurs elsewhere is unknown. Here, we examine large dams worldwide and identify where their catchments intersect with endemic schistosomiasis and the historical habitat ranges of large, migratory Macrobrachium spp. prawns. River prawn habitats are widespread, and we estimate that 277–385 million people live within schistosomiasis-endemic regions where river prawns are or were present (out of the 800 million people who are at risk of schistosomiasis). Using a published repository of schistosomiasis studies in sub-Saharan Africa, we compared infection before and after the construction of 14 large dams for people living in: (i) upstream catchments within historical habitats of native prawns, (ii) comparable undammed watersheds, and (iii) dammed catchments beyond the historical reach of migratory prawns. Damming was followed by greater increases in schistosomiasis within prawn habitats than outside prawn habitats. We estimate that one third to one half of the global population-at-risk of schistosomiasis could benefit from restoration of native prawns. Because dams block prawn migrations, our results suggest that prawn extirpation contributes to the sharp increase of schistosomiasis after damming, and points to prawn restoration as an ecological solution for reducing human disease.
Mary H Hodges
Full Text Available BACKGROUND: A national mapping of Schistosoma haematobium was conducted in Sierra Leone before the mass drug administration (MDA with praziquantel. Together with the separate mapping of S. mansoni and soil-transmitted helminths, the national control programme was able to plan the MDA strategies according to the World Health Organization guidelines for preventive chemotherapy for these diseases. METHODOLOGY/PRINCIPAL FINDINGS: A total of 52 sites/schools were selected according to prior knowledge of S. haematobium endemicity taking into account a good spatial coverage within each district, and a total of 2293 children aged 9-14 years were examined. Spatial analysis showed that S. haematobium is heterogeneously distributed in the country with significant spatial clustering in the central and eastern regions of the country, most prevalent in Bo (24.6% and 8.79 eggs/10 ml, Koinadugu (20.4% and 3.53 eggs/10 ml and Kono (25.3% and 7.91 eggs/10 ml districts. By combining this map with the previously reported maps on intestinal schistosomiasis using a simple probabilistic model, the combined schistosomiasis prevalence map highlights the presence of high-risk communities in an extensive area in the northeastern half of the country. By further combining the hookworm prevalence map, the at-risk population of school-age children requiring integrated schistosomiasis/soil-transmitted helminth treatment regimens according to the coendemicity was estimated. CONCLUSIONS/SIGNIFICANCE: The first comprehensive national mapping of urogenital schistosomiasis in Sierra Leone was conducted. Using a new method for calculating the combined prevalence of schistosomiasis using estimates from two separate surveys, we provided a robust coendemicity mapping for overall urogenital and intestinal schistosomiasis. We also produced a coendemicity map of schistosomiasis and hookworm. These coendemicity maps can be used to guide the decision making for MDA strategies in combination
Full Text Available On the Zanzibar islands, United Republic of Tanzania, elimination of urogenital schistosomiasis is strived for in the coming years. This qualitative study aimed to better understand community knowledge, perceptions, and practices associated with schistosomiasis among school-aged children on Unguja and Pemba islands, in order to inform the development of behavior change interventions contributing to eliminate urogenital schistosomiasis.In 2011, we conducted 35 children's discussion groups, 41 in-depth interviews with parents and teachers, and 5 focus group discussions with community members in Zanzibar. Using a modified-grounded theory approach, we transcribed and coded the narrative data followed by thematic analysis of the emergent themes.Urogenital schistosomiasis is a common experience among children in Zanzibar and typically considered a boys' disease. Children engage in multiple high-risk behaviors for acquiring schistosomiasis because of poor knowledge on disease transmission, lack of understanding on severity of disease-associated consequences, and lack of alternative options for water related activities of daily living and recreational play. Local primary school teachers had little to no training about the disease and no teaching tools or materials for students.Conducting activities in open natural freshwater contaminated by S. haematobium larvae compromises the health of school-aged children in Zanzibar. The perception of urogenital schistosomiasis as a minor illness rather than a serious threat to a child's well-being contributes to the spread of disease. Understanding community perceptions of disease along with the barriers and facilitators to risk reduction behaviors among children can inform health promotion activities, campaigns, and programs for the prevention, control, and elimination of urogenital schistosomiasis in Zanzibar.
Pan, Jie; Liu, Ling; Yan, Yi-hua; Shao, Zhi-wei; Li, Qin; Zhou, Rui-hong
To evaluate the effect of health education path on advanced schistosomiasis patients with splenomegaly in perioperative period. A total of 60 advanced schistosomiasis patients with splenomegaly in perioperative period were randomly divided into an observation group and a control group (30 cases each group). The patients in the observation group were intervened by the nursing and health education from admission to discharge according to the standardized process of health education path, while those in the control group were implemented with the conventional health education. Then the satisfaction of nursing work, hospital stays, hospitalization expenses and mastery of health knowledge of the patients in the two groups were investigated and the results were compared. The satisfaction rates of nursing work of patients in the observation group and the control group were 90% and 60%, respectively, the difference between them was statistically significant (χ2 = 7.57, P education path can promote the rehabilitation of advanced schistosomiasis patients with splenomegaly, and increase the satisfaction as well as improve the mastery of the health knowledge of the patients. Meanwhile, it also can cut down the hospital stays and save the hospitalization expenses.
Kitange, H M; Swai, A B; McLarty, D G; Alberti, K G
A study of the prevalence of schistosomiasis was carried out in 253 school children in Melela, Tanzania, one year after a single dose of praziquantel, 40 mg/kg body weight. The cure rate was 90.4%. However the new incidence estimate was 21.2% in children who were initially negative. The use of reagent strips in urine tests for the detection of urinary schistosomiasis was also evaluated. The presence of blood in the urine was highly sensitive (> 96%) and specific (87%). The sensitivity of proteinuria was less, but it was highly specific (94%). This study shows that chemotherapy will have to be combined with other measures to achieve lasting benefits and raises the question as to how often the population should be treated. It also confirms the value of urine test strips as an indirect diagnostic test for urinary schistosomiasis in an endemic area. Further follow-up is necessary to make useful predictions concerning incidence and reinfection rates in the community. This will also help in deciding how often chemotherapy should be given to the population.
Schistosomiasis is one of the most important parasitic diseases in the world, especially in endemic areas of developing countries. This situation has prompted parasitologist to attempt intensive researches on immune mechanisms, especially those of reinfection immunity associated with eliminating challenge infection. The current knowledge of reinfection immunity against Schistosoma spp. infection was therefore reviewed briefly and discussed with special reference to our data on protective immune responses induced by radiation-attenuated cercarial infection. A recently developed technique of compressed organ autoradiography (COA) has contributed to assessing parasite attrition in immune animals following challenge infection. Our study using COA has demonstrated that major attrition of schistosomula from challenge infection occurs in the skin of CBA/Ca mice vaccinated with 20 Krad gamma radiation-attenuated cercariae of S. mansoni, while in both lungs and liver of similarly vaccinated guinea pig model. Furthermore, gamma-irradiation to cercariae affected their migration potential and surface-antigen profiles. The immunizing stimuli of gamma radiation-attenuated cercariae profoundly affected the expression of responsiveness in vaccinated animals. The change in antigenic profiles and migration potential of those vaccinating population was discussed in relation to the kinetics of reinfection immunity induced in vaccinated amimal models. These works might provide a base line data to develop a practical vaccine for schistosomiasis using defined antigens. It must be emphasized that these vaccines could serve as a practical prophylactic measure for schistosomiasis in the endemic areas, even if the vaccines fail to induce sterilizing immunity. (author). 141 refs.
Silveira-Lemos, Denise; Fernandes Costa-Silva, Matheus; Cardoso de Oliveira Silveira, Amanda; Azevedo Batista, Mauricio; Alves Oliveira-Fraga, Lúcia; Soares Silveira, Alda Maria; Barbosa Alvarez, Maria Carolina; Martins-Filho, Olindo Assis; Gazzinelli, Giovanni; Corrêa-Oliveira, Rodrigo; Teixeira-Carvalho, Andréa
Acute schistosomiasis is associated with a primary exposure and is more commonly seen in nonimmune individuals traveling through endemic regions. In this study, we have focused on the cytokine profile of T lymphocytes evaluated in circulating leukocytes of acute Schistosomiasis mansoni-infected patients (ACT group) before and after praziquantel treatment (ACT-TR group). Our data demonstrated increased values of total leukocytes, eosinophils, and monocytes in both groups. Interestingly, we have observed that patients treated with praziquantel showed increased values of lymphocytes as compared with noninfected group (NI) or ACT groups. Furthermore, a decrease of neutrophils in ACT-TR was observed when compared to ACT group. Analyses of short-term in vitro whole blood stimulation demonstrated that, regardless of the presence of soluble Schistosoma mansoni eggs antigen (SEA), increased synthesis of IFN-γ and IL-4 by T-cells was observed in the ACT group. Analyses of cytokine profile in CD8 T cells demonstrated higher percentage of IFN-γ and IL-4 cells in both ACT and ACT-TR groups apart from increased percentage of IL-10 cells only in the ACT group. This study is the first one to point out the relevance of CD8 T lymphocytes in the immune response induced during the acute phase of schistosomiasis. PMID:23401741
Full Text Available Severe hepatosplenic injury of mansonian schistosomiasis is caused by Th2 mediated granulomatous response against parasite eggs entrapped within the periportal tissue. Subsequent fibrotic scarring and deformation/sclerosing of intrahepatic portal veins lead to portal hypertension, ascites, and oesophageal varices. The murine model of Schistosoma mansoni (S. mansoni infection is suitable to establish the severe hepatosplenic injury of disease within a reasonable time scale for the development of novel antifibrotic or anti-infective strategies against S. mansoni infection. The drawback of the murine model is that the material prepared for complex analysis of egg burden, granuloma size, hepatic inflammation, and fibrosis is limited due to small amounts of liver tissue and blood samples. The objective of our study was the implementation of a macroscopic scoring system for mice livers to determine infection-related organ alterations of S. mansoni infection. In addition, an in vitro biosensor system based on the detection of hepatocellular injury in HepG2/C3A cells following incubation with serum of moderately (50 S. mansoni cercariae and heavily (100 S. mansoni cercariae infected mice affirmed the value of our scoring system. Therefore, our score represents a valuable tool in experimental schistosomiasis to assess severity of hepatosplenic schistosomiasis and reduce animal numbers by saving precious tissue samples.
Mari, Lorenzo; Gatto, Marino; Ciddio, Manuela; Dia, Elhadji D; Sokolow, Susanne H; De Leo, Giulio A; Casagrandi, Renato
Schistosomiasis is a parasitic infection that is widespread in sub-Saharan Africa, where it represents a major health problem. We study the drivers of its geographical distribution in Senegal via a spatially explicit network model accounting for epidemiological dynamics driven by local socioeconomic and environmental conditions, and human mobility. The model is parameterized by tapping several available geodatabases and a large dataset of mobile phone traces. It reliably reproduces the observed spatial patterns of regional schistosomiasis prevalence throughout the country, provided that spatial heterogeneity and human mobility are suitably accounted for. Specifically, a fine-grained description of the socioeconomic and environmental heterogeneities involved in local disease transmission is crucial to capturing the spatial variability of disease prevalence, while the inclusion of human mobility significantly improves the explanatory power of the model. Concerning human movement, we find that moderate mobility may reduce disease prevalence, whereas either high or low mobility may result in increased prevalence of infection. The effects of control strategies based on exposure and contamination reduction via improved access to safe water or educational campaigns are also analyzed. To our knowledge, this represents the first application of an integrative schistosomiasis transmission model at a whole-country scale.
Full Text Available BACKGROUND: Despite significant, steady progress in schistosomiasis control in the People's Republic of China over the past 50 years, available data suggest that the disease has re-emerged with several outbreaks of acute infections in the early new century. In response, a new integrated strategy was introduced. METHODS: This retrospective study was conducted between Jan 2005 and Dec 2012, to explore the effectiveness of a new integrated control strategy that was implemented by the national control program since 2004. RESULTS: A total of 1,047 acute cases were recorded between 2005 and 2012, with an annual reduction in prevalence of 97.7%. The proportion of imported cases of schistosomiasis was higher in 2011 and 2012. Nine clusters of acute infections were detected by spatio-temporal analysis between June and November, indicating that the high risk areas located in the lake and marshland regions. CONCLUSION: This study shows that the new integrated strategy has played a key role in reducing the morbidity of schistosomiasis in the People's Republic of China.
Hua, Ming-gui; Jin, Hua-zhong; Liu, Jian-hua; Duan, Hong-mei; Xu, Xin-mini
To investigate the schistosomiasis epidemic situation changes after its transmission interrupted in Lufeng County in 1986, so as to provide the evidence for formulating the interventions for schistosomiasis elimination. The surveillance of Oncomelania hupensis snail was performed by the systematic sampling, environmental sampling and special environmental comprehensive survey methods. The surveillance of human population was carried out by the sero logical screening method, and the positives were re-examined with the stool hatching method. The surveillance of livestock was performed by the plastic cup of pipe jacking hatching method. The living snails were detected in Lufeng County from 1987 to 2007 except in 1988 and 1994. The two import buffalo infected with schistosomes were detected in 2001 and ni local infected livestock were found. Since 2004, the comprehensive measures, including the social control strategy and surviv al snail elimination, were carried out, and no snails were detected and no schistosome infected persons or livestock were found for 7 consecutive years since 2008. The achievement of schistosomiasis transmission interrupted ha been consolidated in Lufeng County, but most of the historical snail environments have not been modified and there are stil snail breeding conditions. Therefore, we should continue to carry out the snail surveillance.
Full Text Available Schistosomiasis is the second-most widespread tropical parasitic disease after malaria. Various research strategies and treatment programs for achieving the objective of eradicating schistosomiasis within a decade have been recommended and supported by the World Health Organization. One of these approaches is based on the control of snail vectors in endemic areas. Previous field studies have shown that competitor or predator introduction can reduce snail numbers, but no systematic investigation has ever been conducted to identify snail microbial pathogens and evaluate their molluscicidal effects.In populations of Biomphalaria glabrata snails experiencing high mortalities, white nodules were visible on snail bodies. Infectious agents were isolated from such nodules. Only one type of bacteria, identified as a new species of Paenibacillus named Candidatus Paenibacillus glabratella, was found, and was shown to be closely related to P. alvei through 16S and Rpob DNA analysis. Histopathological examination showed extensive bacterial infiltration leading to overall tissue disorganization. Exposure of healthy snails to Paenibacillus-infected snails caused massive mortality. Moreover, eggs laid by infected snails were also infected, decreasing hatching but without apparent effects on spawning. Embryonic lethality was correlated with the presence of pathogenic bacteria in eggs.This is the first account of a novel Paenibacillus strain, Ca. Paenibacillus glabratella, as a snail microbial pathogen. Since this strain affects both adult and embryonic stages and causes significant mortality, it may hold promise as a biocontrol agent to limit schistosomiasis transmission in the field.
Boelee, Eline; Laamrani, Hammou
Summary Akka oasis, in the province of Tata, southern Morocco, is one of the oldest foci of urinary schistosomiasis in Morocco where transmission is still taking place. We report the results of two studies: a cross-sectional snail survey investigated the distribution of Bulinus truncatus in relation to habitat factors in the Akka traditional irrigation system. The presence of aquatic vegetation, especially Potamogeton sp. was identified as a key factor determining snail occurrence and abundance in canals, impoundments and isolated small puddles and streamlets in the Akka riverbed. In a participatory rapid appraisal, the community identified snail control as a way to reduce transmission of schistosomiasis. Without any further outside incentives, the local irrigation committee implemented repeated cleaning and vegetation removal in canals. A longitudinal study evaluated the effect of these measures on populations of B. truncatus. Snail and egg mass densities showed significant reductions after repeated vegetation clearing in the study sites. The participatory approach led to low-cost, environment-friendly schistosomiasis control measures that were effective and sustainable.
Greer, G J; Anuar, H
Using ELISA and COPT diagnostic tests, serological evidence of Malaysian schistosomiasis was discovered among Orang Asli populations from three areas in Peninsular Malaysia. Serum samples collected in 1975 indicated an ELISA-positive prevalence of 25% and a COPT prevalence of 11% from Pos Iskandar, Pahang and an ELISA prevalence of 13% and a COPT of 4% from Bukit Lanjan, Selangor. Resurveys at these site in 1982-1984 showed a continued presence of serological positive individuals but prevalence rates were markedly lower: 7% and 1% for ELISA and 4% and 2% for COPT at Pos Iskandar and Bukit Lanjan respectively. Snail hosts were not found at either site. The source of infection for persons living in these lowland areas remains unknown. In a third area, Kuala Tahan, Pahang, located in the foothills of the central mountain range, foci of transmission have been found near to Orang Asli settlements. The serological prevalence rate among Negrito Orang Asli in that study area was 9% for ELISA and 4% for COPT. Thirty-three of 36 COPT-positive sera produced vacuolated bleb precipates and in 31 these were the only reactions seen. The high percentage of positives producing only these precipates suggests that among Orang Asli schistosomiasis patients such reactions are not an indication of recently acquired infection as has been reported for schistosomiasis patients in the Philippines.
Okeke, Ogochukwu Caroline; Ubachukwu, Patience Obiageli
In view of the massive rural-to-urban migration in Nigeria, investigations on transmission of urinary schistosomiasis were carried out in urban and semi-urban communities in Nike Lake area of Enugu State, Nigeria. Urine samples of school children were tested for micro-haematuria using reagent strips followed by microscopic examination for Schistosoma haematobium eggs. Water contact sites were also identified and sampled for snails. The overall prevalence of S. haematobium eggs in school children was 4.64%. The mean intensity of infection was 1.14 ± 0.41 eggs/10ml urine. Males had insignificantly higher prevalence and intensity of S. haematobium infection than females. The youngest age group (4-7 years) had no infection. The prevalence of micro-haematuria (6.2%) was higher than that of microscopy, and this correlated positively with prevalence (r = 0.65, P < 0.01) and intensity (r = 0.50, P < 0.01) of the infection. Potential intermediate host of human shistosome collected were: Bulinus globosus, B. senegalensis and Biomphalaria pfeifferi. However, only B. globosus shed cercariae of S. haematobium, with a snail infection rate of 0.73%. Transmission was in the dry season coinciding with the drying of wells. The results revealed that urinary schistosomiasis is prevalent, and that B. globosus and not B. truncatus as previously reported is the main intermediate host of urinary schistosomiasis in this part of Enugu State.
Ramzi A Alsallaq
Full Text Available Mass drug administration (MDA of praziquantel has been the intervention of choice against schistosomiasis but with limited success in interrupting the transmission. The development of anti-Schistosoma vaccines is underway. Our objective is to quantify the population-level impact of anti-Schistosoma vaccines when administered alone and in combination with mass drug administration (MDA and determine factors in vaccine design and public health implementation that optimize vaccination role in schistosomiasis control and elimination.We developed a deterministic compartmental model simulation of schistosomiasis transmission in a high-risk Kenyan community, including stratification by age, parasite burden, and vaccination status. The modeled schistosomiasis vaccines differed in terms of vaccine duration of protection (durability and three biological efficacies. These are vaccine susceptibility effect (SE of reducing person's susceptibility to Schistosoma acquisition, vaccine mortality effect (ME of reducing established worm burden and vaccine fecundity effect (FE of reducing egg release by mature worms. We quantified the population-level impact of vaccination over two decades under diverse vaccination schemes (childhood vs. mass campaigns, with different age-targeting scenarios, different risk settings, and with combined intervention with MDA. We also assessed the sensitivity of our predictions to uncertainties in model parameters. Over two decades, our base case vaccine with 80% SE, FE, and ME efficacies, 10 years' durability, provided by mass vaccination every 10 years, reduced host prevalence, mean intensity, incidence, and patent snail prevalence to 31%, 20 eggs/10-ml sample/person, 0.87 worm/person-year, and 0.74%, from endemic-state values of 71%, 152, 3.3, and 0.98%, respectively. Lower impact was found when coverage did not encompass all potential contaminators, and childhood-only vaccination schemes showed delayed and lower impact. In lower
Boissier, Jérôme; Grech-Angelini, Sébastien; Webster, Bonnie L; Allienne, Jean-François; Huyse, Tine; Mas-Coma, Santiago; Toulza, Eve; Barré-Cardi, Hélène; Rollinson, David; Kincaid-Smith, Julien; Oleaga, Ana; Galinier, Richard; Foata, Joséphine; Rognon, Anne; Berry, Antoine; Mouahid, Gabriel; Henneron, Rémy; Moné, Hélène; Noel, Harold; Mitta, Guillaume
Schistosomiasis is a snail-borne parasitic disease endemic in several tropical and subtropical countries. However, in the summer of 2013, an unexpected outbreak of urogenital schistosomiasis occurred in Corsica, with more than 120 local people or tourists infected. We used a multidisciplinary approach to investigate the epidemiology of urogenital schistosomiasis in Corsica, aiming to elucidate the origin of the outbreak. We did parasitological and malacological surveys at nine potential sites of infection. With the snails found, we carried out snail-parasite compatibility experiments by exposing snails to schistosome larvae recovered from the urine of a locally infected Corsican patient. Genetic analysis of both mitochondrial (cox1) and nuclear (internal transcribed spacer) DNA data from the Schistosoma eggs or miracidia recovered from the infected patients was conducted to elucidate the epidemiology of this outbreak. We identified two main infection foci along the Cavu River, with many Bulinus truncatus snails found in both locations. Of the 3544 snails recovered across all sites, none were naturally infected, but laboratory-based experimental infections confirmed their compatibility with the schistosomes isolated from patients. Molecular characterisation of 73 eggs or miracidia isolated from 12 patients showed infection with Schistosoma haematobium, S haematobium-Schistosoma bovis hybrids, and S bovis. Further sequence data analysis also showed that the Corsican schistosomes were closely related to those from Senegal in west Africa. The freshwater swimming pools of the Cavu River harbour many B truncatus snails, which are capable of transmitting S haematobium-group schistosomes. Our molecular data suggest that the parasites were imported into Corsica by individuals infected in west Africa, specifically Senegal. Hybridisation between S haematobium and the cattle schistosome S bovis had a putative role in this outbreak, showing how easily and rapidly urogenital
Alsallaq, Ramzi A; Gurarie, David; Ndeffo Mbah, Martial; Galvani, Alison; King, Charles
Mass drug administration (MDA) of praziquantel has been the intervention of choice against schistosomiasis but with limited success in interrupting the transmission. The development of anti-Schistosoma vaccines is underway. Our objective is to quantify the population-level impact of anti-Schistosoma vaccines when administered alone and in combination with mass drug administration (MDA) and determine factors in vaccine design and public health implementation that optimize vaccination role in schistosomiasis control and elimination. We developed a deterministic compartmental model simulation of schistosomiasis transmission in a high-risk Kenyan community, including stratification by age, parasite burden, and vaccination status. The modeled schistosomiasis vaccines differed in terms of vaccine duration of protection (durability) and three biological efficacies. These are vaccine susceptibility effect (SE) of reducing person's susceptibility to Schistosoma acquisition, vaccine mortality effect (ME) of reducing established worm burden and vaccine fecundity effect (FE) of reducing egg release by mature worms. We quantified the population-level impact of vaccination over two decades under diverse vaccination schemes (childhood vs. mass campaigns), with different age-targeting scenarios, different risk settings, and with combined intervention with MDA. We also assessed the sensitivity of our predictions to uncertainties in model parameters. Over two decades, our base case vaccine with 80% SE, FE, and ME efficacies, 10 years' durability, provided by mass vaccination every 10 years, reduced host prevalence, mean intensity, incidence, and patent snail prevalence to 31%, 20 eggs/10-ml sample/person, 0.87 worm/person-year, and 0.74%, from endemic-state values of 71%, 152, 3.3, and 0.98%, respectively. Lower impact was found when coverage did not encompass all potential contaminators, and childhood-only vaccination schemes showed delayed and lower impact. In lower prevalence
Le, Aiping; Zhang, Lunli; Liu, Wei; Li, Xiaopeng; Ren, Jianwei; Ning, An
A structural equation model was used for verification with chronic schistosomiasis to investigate the coagulation-anticoagulation system imbalance and to deduce the mechanism of D-dimer (D-D) level elevation in patients with advanced schistosome hepatic disease. We detected the plasma levels of tissue-type fiber plasminogen activator (tPA), urokinase type plasminogen activator (uPA), plasmin-antiplasmin complex (PAP), plasminogen (PLG), antithrombin (AT), plasminogen activator inhibitor 1 (PAI1), D-D, factor VIII: C (FVIII:C), antithrombin-III (AT-III), PLG, protein S (PS), and protein C (PC) in the healthy people as control (69), patients with chronic schistosomiasis (150) or advanced chronic schistosomiasis (90). FVIII, PAP, D-D, tPA, and uPA plasma levels were significantly higher in the chronic group than in the control group and were also significantly higher in the advanced group. However, AT-III, PC, PS, AT, PLG, and PAI1 plasma levels in the advanced and chronic groups were significantly lower than those in the control group. With progression of disease in patients with schistosomiasis japonica, a hypercoagulable state is induced by the coagulation-anticoagulation imbalance, eventually leading to patients with high levels of D-D. Furthermore, we established a structural equation model path of a "chronic schistosomiasis disease stage-(coagulation-anticoagulation-fibrinolysis)-D-D." By using analysis of moment structures (AMOS), it was shown that the chronic schistosomiasis stage was positively related to factor VIII and had negative correlation with AT-III; a good positive correlation with PAP, tPA, and uPA; and a good negative correlation with PLG and PAI1. In addition, our results show that the path coefficient of anticoagulation-fibrinolysis system to the chronic stage of schistosomiasis or D-D levels was significantly higher than that of the coagulation system. In conclusion, the coagulation and fibrinolysis imbalance in patients with chronic
Braae, Uffe Christian; Magnussen, Pascal; Harrison, Wendy
Taenia solium is found throughout sub-Saharan Africa and co-endemic with schistosomiasis in many regions. Taenia solium leads to taeniosis and neurocysticercosis - the leading cause of preventable epilepsy globally. This study aimed to assess the effects of the National Schistosomiasis Control...
Umar, A S; Parakoyi, D B
Children are known to be the major reservior of urinary schistosomiasis in endemic communities. This study was conducted to assess the prevalence and intensity of urinary schistosomiasis among school children living along the Bakalori dam. The study was a cross sectional assessment using a pre-tested standardised structured questionnaire interviews. A total of 240 pupils were recruited through a multistage sampling technique. Urine samples from the pupils were examined for the presence of ova of schistosoma haematobium. A total of 125(52.1%) of respondents were 11-12 years old with a mean age of 11.7 +/- 1.4 years. The prevalence of urinary schistosomiasis among school children was found to be 42.1%. The highest age and sex specific prevalence rate was recorded among the 13-14 years age group for both males (43.1%) and females (50.0%). The age, sex, level of school attainment, occupation of respondents' father/guardian and source of water for domestic use were found to have a significant statistical association with the risk of being infected (P<0.05). It is concluded that the prevalence and intensity of urinary schistosomiasis is high. To reverse the situation requires mass chemotherapy, community mobilisation and provision of portable water. Key words: schistosomiasis, prevalence, intensity, school children, dams.
Ajakaye, Oluwaremilekun G; Adedeji, Oluwatola I; Ajayi, Paul O
Schistosomiasis is a parasitic disease and its distribution, in space and time, can be influenced by environmental factors such as rivers, elevation, slope, land surface temperature, land use/cover and rainfall. The aim of this study is to identify the areas with suitable conditions for schistosomiasis transmission on the basis of physical and environmental factors derived from satellite imagery and spatial analysis for Akure North Local Government Area (LGA) of Ondo State. Nigeria. This was done through methodology multicriteria evaluation (MCE) using Saaty's analytical hierarchy process (AHP). AHP is a multi-criteria decision method that uses hierarchical structures to represent a problem and makes decisions based on priority scales. In this research AHP was used to obtain the mapping weight or importance of each individual schistosomiasis risk factor. For the purpose of identifying areas of schistosomiasis risk, this study focused on temperature, drainage, elevation, rainfall, slope and land use/land cover as the factors controlling schistosomiasis incidence in the study area. It is by reclassifying and overlaying these factors that areas vulnerable to schistosomiasis were identified. The weighted overlay analysis was done after each factor was given the appropriate weight derived through the analytical hierarchical process. The prevalence of urinary schistosomiasis in the study area was also determined by parasitological analysis of urine samples collected through random sampling. The results showed varying risk of schistosomiasis with a larger portion of the area (82%) falling under the high and very high risk category. The study also showed that one community (Oba Ile) had the lowest risk of schistosomiasis while the risk increased in the four remaining communities (Iju, Igoba, Ita Ogbolu and Ogbese). The predictions made by the model correlated strongly with observations from field study. The high risk zones corresponded to known endemic communities. This
David Z. Munisi
Full Text Available Abstract Background Globally school-age children, adolescents and young adults bear the highest burden of schistosomiasis. When developing a specific intervention to improve community’s knowledge, attitudes, and practices (KAPs, existing KAPs must be taken into account. Therefore, this study was designed to determine schoolchildren’s KAPs on schistosomiasis in the study area. Methods A cross-sectional study was conducted in Busanga and Kibuyi villages involving 513 schoolchildren. A pre-tested questionnaire was used to collect socio-demographic data and to assess KAP on schistosomiasis among primary schoolchildren in the study area. Results Of the 488 interviewed children, 391 (80.12% reported to have heard of schistosomiasis, with the majority 289 (73.91% citing school as the source of this knowledge. Swimming in the lake, worms, witchcraft, and mosquitoes were mentioned to be the cause for intestinal schistosomiasis. Fishing in the lake, drinking unboiled lake water, walking bare footed, and shaking hands were reported to be practices that may lead to contracting schistosomiasis. Only 156 (39.90% of the study respondents reported to know the signs of intestinal schistosomiasis. Avoiding swimming in the lake, drinking unboiled water and eating unwashed fruits were mentioned as preventive measures. Nearly 85% (412 reported understanding that there was a disease known as schistosomiasis; additionally, 419 (85.86% considered schistosomiasis as a dangerous disease and 418 (85.66% believed that schistosomiasis was treatable. Fishermen and schoolchildren were reported to be groups most at risk of schistosomiasis infection. Visiting the lake (for swimming and other gatherings was a common practice among study participants 471 (96.52%.Nearly 93% (451 of participants mentioned using lake water for domestic chores, and, although 407 (84.61% reported to own a toilet at home, only 229 (55.31% reported to always use a toilet for sanitation purposes
Sun, Le-Ping; Tian, Zeng-Xi; Yang, Kun; Hong, Qing-Biao; Gao, Yang; Gao, Yuan; Zhang, Lian-Heng; Yang, Guo-Jing; Min, Jie; Ge, Jun; Wu, Hong-Hui; Huang, Yi-Xin; Liang, You-Sheng
To evaluate the effect of comprehensive control for schistosomiasis in key areas of Jiangsu Province. The basic data and the data of implementation of comprehensive control measures were collected from the key areas of Jiangsu Province, including 30 townships, 87 marshlands and 78 anchor points. A field survey was carried out to investigate the Oncomelania snail status by using the systematic sampling method and schistosomiasis morbidity in humans and animals in the 12 key counties (districts). The changes of snail status and morbidity of humans and animals were statistically analyzed in key counties (districts) where comprehensive control measures was implemented, and the effects of schistosomiasis control before and after the implementation of the comprehensive control were compared. From 2008 to 2010, a total of 84 100 harmless latrines were constructed, 339 600 persons were examined, 2.6938 million people received health education, 112 000 protective creams and 798 000 publicity materials were allocated, 9 085 domestic animals were reared in pens, 11 800 domestic animals were examined, 130 high-risk cattle were eliminated in 30 key townships of 12 countries (districts), Jiangsu Province. A total of 19 640.78 hm2 were controlled with molluscicides, 798 warning tablets were placed, 116.07 hm2 of farmlands were ploughed up and planted, 306.80 hm2 were dug for fish culture, and 506.74 hm2 were planted with trees for snail control in 87 high-risk marshlands. A total of 118.83 million Yuan were invested into the water resources development projects, 39.82 km-long rivers were dredged, 70.04 km-long bank were concreted, 30 culvert gates were re-constructed, and 22 snail sedimentation tanks were built. In the 78 anchor points, 95 harmless public toilets were built, 3 192 stool container were allocated, 28 700 boatmen were examined, 71 600 protective creams and 53 200 publicity materials were allocated, and 46 600 persons received health education. Following the
Full Text Available Background: Schistosomiasis is a debilitating disease, infects millions of people in tropical and subtropical regions. This study assessed the situation of the urinary schistosomiasis among schoolchildren of the Alsaial Alsagair village, Sudan.Methods: A cross-sectional survey was carried out in 2016, in the Alsaial Alsagair village, and 385 samples of urine were collected and processed using the centrifugation/sedimentation technique.Results: The overall prevalence and intensity of the disease among the pupils studied were 1.82% and 40.1 eggs/10ml urine, respectively. The prevalence of infection among male pupils was 3.1%, and for females was 0.52%, while the intensity among males was 42.3 eggs/10ml and for females was 27 eggs/10ml urine. No significant difference in the disease prevalence between the 7-10 yr age group and the 11-14 yr age group was found, while the over 14 yr age group was found to be free from infection. However, a considerably higher intensity of the parasite was found among the 7-10 yr age group compared to the other age group infected. A high prevalence and intensity of infection was observed among pupils who were active in swimming and working in the fields. Most of the pupils interviewed were found to be unaware of the disease and the prevalence and intensity of the infection was found to be higher among the group who were aware of the disease.Conclusion: Findings show the need for an integrated control program against urinary schistosomiasis including the treatment of all infected children and the implementation of a health education program.
Perez-Saez, Javier; Bertuzzo, Enrico; Frohelich, Jean-Marc; Mande, Theophile; Ceperley, Natalie; Sou, Mariam; Yacouba, Hamma; Maiga, Hamadou; Sokolow, Susanne; De Leo, Giulio; Casagrandi, Renato; Gatto, Marino; Mari, Lorenzo; Rinaldo, Andrea
We study the spatial geography of schistosomiasis in the african context of Burkina Faso by means of a spatially explicit model of disease dynamics and spread. The relevance of our work lies in its ability to describe quantitatively a geographic stratification of the disease burden capable of reproducing important spatial differences, and drivers/controls of disease spread. Among the latters, we consider specifically the development and management of water resources which have been singled out empirically as an important risk factor for schistosomiasis. The model includes remotely acquired and objectively manipulated information on the distributions of population, infrastructure, elevation and climatic drivers. It also includes a general description of human mobility and addresses a first-order characterization of the ecology of the intermediate host of the parasite causing the disease based on maximum entropy learning of relevant environmenal covariates. Spatial patterns of the disease were analyzed about their disease-free equilibrium by proper extraction and mapping of suitable eigenvectors of the Jacobian matrix subsuming all stability properties of the system. Human mobility was found to be a primary control of both pathogen invasion success and of the overall distribution of disease burden. The effects of water resources development were studied by accounting for the (prior and posterior) average distances of human settlements from water bodies that may serve as suitable habitats to the intermediate host of the parasite. Water developments, in combination with human mobility, were quantitatively related to disease spread into regions previously nearly disease-free and to large-scale empirical incidence patterns. We concluded that while the model still needs refinements based on field and epidemiological evidence, the framework proposed provides a powerful tool for large-scale, long-term public health planning and management of schistosomiasis.
Gong, Zheng; Luo, Qi-Zhi; Lin, Lin [Department of Immunology, College of Basic Medical Sciences, Central South University, Changsha, Hunan Province (China); Su, Yu-Ping; Peng, Hai-Bo [Central Blood Bank in Yueyang, Yueyang, Hunan Province (China); Du, Kun; Yu, Ping [Department of Immunology, College of Basic Medical Sciences, Central South University, Changsha, Hunan Province (China); Wang, Shi-Ping [Key Laboratory of Schistosomiasis in Hunan, Department of Parasitology, College of Basic Medical Sciences, Central South University, Changsha, Hunan Province (China)
Major histocompatibility complex class I chain-related A (MICA) is a highly polymorphic gene located within the MHC class I region of the human genome. Expressed as a cell surface glycoprotein, MICA modulates immune surveillance by binding to its cognate receptor on natural killer cells, NKG2D, and its genetic polymorphisms have been recently associated with susceptibility to some infectious diseases. We determined whether MICA polymorphisms were associated with the high rate of Schistosoma parasitic worm infection or severity of disease outcome in the Dongting Lake region of Hunan Province, China. Polymerase chain reaction-sequence specific priming (PCR-SSP) and sequencing-based typing (SBT) were applied for high-resolution allele typing of schistosomiasis cases (N = 103, age range = 36.2-80.5 years, 64 males and 39 females) and healthy controls (N = 141, age range = 28.6-73.3 years, 73 males and 68 females). Fourteen MICA alleles and five short-tandem repeat (STR) alleles were identified among the two populations. Three (MICA*012:01/02, MICA*017 and MICA*027) showed a higher frequency in healthy controls than in schistosomiasis patients, but the difference was not significantly correlated with susceptibility to S. japonicum infection (Pc > 0.05). In contrast, higher MICA*A5 allele frequency was significantly correlated with advanced liver fibrosis (Pc < 0.05). Furthermore, the distribution profile of MICA alleles in this Hunan Han population was significantly different from those published for Korean, Thai, American-Caucasian, and Afro-American populations (P < 0.01), but similar to other Han populations within China (P > 0.05). This study provides the initial evidence that MICA genetic polymorphisms may underlie the severity of liver fibrosis occurring in schistosomiasis patients from the Dongting Lake region.
Mak Tippi K
Full Text Available Abstract The economy of China continues to boom and so have its biomedical research and related publishing activities. Several so-called neglected tropical diseases that are most common in the developing world are still rampant or even emerging in some parts of China. The purpose of this article is to document the significant research potential from the Chinese biomedical bibliographic databases. The research contributions from China in the epidemiology and control of schistosomiasis provide an excellent illustration. We searched two widely used databases, namely China National Knowledge Infrastructure (CNKI and VIP Information (VIP. Employing the keyword "Schistosoma" ( and covering the period 1990–2006, we obtained 10,244 hits in the CNKI database and 5,975 in VIP. We examined 10 Chinese biomedical journals that published the highest number of original research articles on schistosomiasis for issues including languages and open access. Although most of the journals are published in Chinese, English abstracts are usually available. Open access to full articles was available in China Tropical Medicine in 2005/2006 and is granted by the Chinese Journal of Parasitology and Parasitic Diseases since 2003; none of the other journals examined offered open access. We reviewed (i the discovery and development of antischistosomal drugs, (ii the progress made with molluscicides and (iii environmental management for schistosomiasis control in China over the past 20 years. In conclusion, significant research is published in the Chinese literature, which is relevant for local control measures and global scientific knowledge. Open access should be encouraged and language barriers removed so the wealth of Chinese research can be more fully appreciated by the scientific community.
Josué de Moraes
Full Text Available BACKGROUND: Schistosomiasis is a major endemic disease that affects hundreds of millions worldwide. Since the treatment and control of this parasitic disease rely on a single drug, praziquantel, it is imperative that new effective drugs are developed. Here, we report that phytol, a diterpene alcohol from chlorophyll widely used as a food additive and in medicinal fields, possesses promising antischistosomal properties in vitro and in a mouse model of schistosomiasis mansoni. METHODS AND FINDINGS: In vitro, phytol reduced the motor activity of worms, caused their death and confocal laser scanning microscopy analysis showed extensive tegumental alterations in a concentration-dependent manner (50 to 100 µg/mL. Additionally, phytol at sublethal doses (25 µg/mL reduced the number of Schistosoma mansoni eggs. In vivo, a single dose of phytol (40 mg/kg administered orally to mice infected with adult S. mansoni resulted in total and female worm burden reductions of 51.2% and 70.3%, respectively. Moreover, phytol reduced the number of eggs in faeces (76.6% and the frequency of immature eggs (oogram pattern was significantly reduced. The oogram also showed increases in the proportion of dead eggs. Confocal microcopy studies revealed tegumental damage in adult S. mansoni recovered from mice, especially in female worms. CONCLUSIONS: The significant reduction in parasite burden by this chlorophyll molecule validates phytol as a promising drug and offers the potential of a new direction for chemotherapy of human schistosomiasis. Phytol is a common food additive and nonmutagenic, with satisfactory safety. Thus, phytol has potential as a safe and cost-effective addition to antischistosomal therapy.
Soliman, Nema Ali; Keshk, Walaa Arafa; Shoheib, Zeinab Salah; Ashour, Dalia Salah; Shamloula, Maha Moustafa
Schistosomiasis is a parasitic disease causing chronic ill health in humans with a serious consequences for socio-economic development in tropical and subtropical regions. There is also evidence linking Schistosoma mansoni to colonic carcinoma occurrence. The aim of this study was to evaluate some inflammatory and oxidative stress biomarkers, as well as L-fucose as linkers between intestinal schistosomiasis and colonic dysplasia development in mice. This study was conducted upon 80 mice that were divided the control group (10 non infected mice) and infected group which was subdivided into 7 sub-groups (10 mice each) according to the time of sacrifaction in the post infection (p.i.) period, 10 mice being sacrificed every two weeks from 6 weeks p.i. to 18 weeks p.i. Tumor necrosis factor alpha (TNF-α), inducible nitric oxide synthase (iNOS), and pentraxin 3 (PTX3) levels were estimated by immunoassay. The L-fucose level, and thioredoxin reductase (TrxR) and lactate dehydrogenase (LDH) activities were also evaluated in colonic tissue. The current study revealed statistically significant elevation in the studied biochemical markers especially at 16 and 18 weeks p.i. The results were confirmed by histopathological examination that revealed atypical architectural and cytological changes in the form of epithelial surface serration and nuclear hyper-chromatizia at 14, 16 and 18 weeks p.i. inflammation, oxidative stress and L-fucose together may form an important link between Schistosomal mansoni infection and colonic dysplasia and they can be new tools for prediction of colonic dysplasia development in experimental schistosomiasis.
Full Text Available Six hundred million people are at risk of infection by Schistosoma mansoni. MHC haplotypes have been reported to segregate with susceptibility to schistosomiasis in murine models. In humans, a major gene related to susceptibility/resistance to infection by S. mansoni (SM1 and displaying the mean fecal egg count as phenotype was detected by segregation analysis. This gene displayed a codominant mode of inheritance with an estimated frequency of 0.20-0.25 for the deleterious allele and accounted for more than 50% of the variance of infection levels. To determine if the SM1 gene segregates with the human MHC chromosomal region, we performed a linkage study by the lod score method. We typed for HLA-A, B, C, DR and DQ antigens in 11 informative families from an endemic area for schistosomiasis in Bahia, Brazil, by the microlymphocytotoxicity technique. HLA-DR typing by the polymerase chain reaction with sequence-specific primers (PCR-SSP and HLA-DQ were confirmed by PCR-sequence-specific oligonucleotide probes (PCR-SSOP. The lod scores for the different q values obtained clearly indicate that there is no physical linkage between HLA and SM1 genes. Thus, susceptibility or resistance to schistosomiasis, as defined by mean fecal egg count, is not primarily dependent on the host's HLA profile. However, if the HLA molecule plays an important role in specific immune responses to S. mansoni, this may involve the development of the different clinical aspects of the disease such as granuloma formation and development of hepatosplenomegaly.
de Moraes, Josué; de Oliveira, Rosimeire N.; Costa, Jéssica P.; Junior, Antonio L. G.; de Sousa, Damião P.; Freitas, Rivelilson M.; Allegretti, Silmara M.; Pinto, Pedro L. S.
Background Schistosomiasis is a major endemic disease that affects hundreds of millions worldwide. Since the treatment and control of this parasitic disease rely on a single drug, praziquantel, it is imperative that new effective drugs are developed. Here, we report that phytol, a diterpene alcohol from chlorophyll widely used as a food additive and in medicinal fields, possesses promising antischistosomal properties in vitro and in a mouse model of schistosomiasis mansoni. Methods and findings In vitro, phytol reduced the motor activity of worms, caused their death and confocal laser scanning microscopy analysis showed extensive tegumental alterations in a concentration-dependent manner (50 to 100 µg/mL). Additionally, phytol at sublethal doses (25 µg/mL) reduced the number of Schistosoma mansoni eggs. In vivo, a single dose of phytol (40 mg/kg) administered orally to mice infected with adult S. mansoni resulted in total and female worm burden reductions of 51.2% and 70.3%, respectively. Moreover, phytol reduced the number of eggs in faeces (76.6%) and the frequency of immature eggs (oogram pattern) was significantly reduced. The oogram also showed increases in the proportion of dead eggs. Confocal microcopy studies revealed tegumental damage in adult S. mansoni recovered from mice, especially in female worms. Conclusions The significant reduction in parasite burden by this chlorophyll molecule validates phytol as a promising drug and offers the potential of a new direction for chemotherapy of human schistosomiasis. Phytol is a common food additive and nonmutagenic, with satisfactory safety. Thus, phytol has potential as a safe and cost-effective addition to antischistosomal therapy. PMID:24392173
Maha M Eissa
Full Text Available Miltefosine (MFS is an alkylphosphocholine used for the local treatment of cutaneous metastases of breast cancer and oral therapy of visceral leishmaniasis. Recently, the drug was reported in in vitro and preclinical studies to exert significant activity against different developmental stages of schistosomiasis mansoni, a widespread chronic neglected tropical disease (NTD. This justified MFS repurposing as a potential antischistosomal drug. However, five consecutive daily 20 mg/kg doses were needed for the treatment of schistosomiasis mansoni in mice. The present study aims at enhancing MFS efficacy to allow for a single 20mg/kg oral dose therapy using a nanotechnological approach based on lipid nanocapsules (LNCs as oral nanovectors. MFS was incorporated in LNCs both as membrane-active structural alkylphospholipid component and active antischistosomal agent. MFS-LNC formulations showed high entrapment efficiency (EE%, good colloidal properties, sustained release pattern and physical stability. Further, LNCs generally decreased MFS-induced erythrocyte hemolytic activity used as surrogate indicator of membrane activity. While MFS-free LNCs exerted no antischistosomal effect, statistically significant enhancement was observed with all MFS-LNC formulations. A maximum effect was achieved with MFS-LNCs incorporating CTAB as positive charge imparting agent or oleic acid as membrane permeabilizer. Reduction of worm load, ameliorated liver pathology and extensive damage of the worm tegument provided evidence for formulation-related efficacy enhancement. Non-compartmental analysis of pharmacokinetic data obtained in rats indicated independence of antischistosomal activity on systemic drug exposure, suggesting possible gut uptake of the stable LNCs and targeting of the fluke tegument which was verified by SEM. The study findings put forward MFS-LNCs as unique oral nanovectors combining the bioactivity of MFS and biopharmaceutical advantages of LNCs
Eissa, Maha M; El-Moslemany, Riham M; Ramadan, Alyaa A; Amer, Eglal I; El-Azzouni, Mervat Z; El-Khordagui, Labiba K
Miltefosine (MFS) is an alkylphosphocholine used for the local treatment of cutaneous metastases of breast cancer and oral therapy of visceral leishmaniasis. Recently, the drug was reported in in vitro and preclinical studies to exert significant activity against different developmental stages of schistosomiasis mansoni, a widespread chronic neglected tropical disease (NTD). This justified MFS repurposing as a potential antischistosomal drug. However, five consecutive daily 20 mg/kg doses were needed for the treatment of schistosomiasis mansoni in mice. The present study aims at enhancing MFS efficacy to allow for a single 20mg/kg oral dose therapy using a nanotechnological approach based on lipid nanocapsules (LNCs) as oral nanovectors. MFS was incorporated in LNCs both as membrane-active structural alkylphospholipid component and active antischistosomal agent. MFS-LNC formulations showed high entrapment efficiency (EE%), good colloidal properties, sustained release pattern and physical stability. Further, LNCs generally decreased MFS-induced erythrocyte hemolytic activity used as surrogate indicator of membrane activity. While MFS-free LNCs exerted no antischistosomal effect, statistically significant enhancement was observed with all MFS-LNC formulations. A maximum effect was achieved with MFS-LNCs incorporating CTAB as positive charge imparting agent or oleic acid as membrane permeabilizer. Reduction of worm load, ameliorated liver pathology and extensive damage of the worm tegument provided evidence for formulation-related efficacy enhancement. Non-compartmental analysis of pharmacokinetic data obtained in rats indicated independence of antischistosomal activity on systemic drug exposure, suggesting possible gut uptake of the stable LNCs and targeting of the fluke tegument which was verified by SEM. The study findings put forward MFS-LNCs as unique oral nanovectors combining the bioactivity of MFS and biopharmaceutical advantages of LNCs, allowing targeting
Ogochukwu Caroline Okeke
Full Text Available Background: In view of the massive rural-to-urban migration in Nigeria, investigations on transmission of urinary schistosomiasis were carried out in urban and semi-urban communities in Nike Lake area of Enugu State, Nigeria.Methods: Urine samples of school children were tested for micro-haematuria using reagent strips followed by microscopic examination for Schistosoma haematobium eggs. Water contact sites were also identified and sampled for snails.Results: The overall prevalence of S. haematobium eggs in school children was 4.64%. The mean intensity of infection was 1.14 + 0.41 eggs/10ml urine. Males had insignificantly higher prevalence and intensity of S. haematobium infection than females. The youngest age group (4-7 years had no infection. The prevalence of micro-haematuria (6.2% was higher than that of microscopy, and this correlated positively with prevalence (r=0.65, P < 0.01 and intensity (r=0.50, P < 0.01 of the infection. Potential intermediate host of human shistosome collected were: Bulinus globosus, B. senegalensis and Biomphalaria pfeifferi. However, only B. globosus shed cercariae of S. haematobium, with a snail infection rate of 0.73%. Transmission was in the dry season coinciding with the drying of wells.Conclusion: The results revealed that urinary schistosomiasis is prevalent, and that B. globosus and not B. truncatus as previously reported is the main intermediate host of urinary schistosomiasis in this part of Enugu State
Furu, Peter; Chimbari, Moses; Makuratirwa, Samson
influence on the epidemiology of malaria and schistosomiasis in Gwanda District, Zimbabwe. Knowledge of these factors is crucial as they may be important confounders in the interpretation of the possible effects of climate change and variability on the two diseases. A detailed inventory and mapping...... of institutional factors was done with a view to analyse their role in past and present transmission patterns and manifestations in vulnerable population groups. Methods included stakeholder analyses, policy framework analyses, systems analyses and key-informant interviews targeting the sectors of health...
Muhumuza, Simon; Olsen, Annette; Nuwaha, Fred
Despite attempts to control intestinal schistosomiasis through school-based mass drug administration (MDA) with praziquantel using school teachers in Uganda, less than 30% of the school children take the treatment in some areas. The aim of the study was to understand why the uptake of praziquantel...... among school children is low and to suggest strategies for improved uptake. This was a cross-sectional qualitative study in which 24 focus group discussions and 15 key informant interviews were conducted 2 months after MDA. The focus group discussions were held with school children in twelve primary...
Full Text Available Abstract Background Schistosomiasis and soil-transmitted helminthiasis (STHs are target neglected tropical diseases (NTDs of preventive chemotherapy, but the control and elimination of these diseases have been impeded due to resource constraints. Few reports have described study protocol to draw on when conducting a nationwide survey. We present a detailed methodological description of the integrated mapping of schistosomiasis and STHs on the basis of our experiences, hoping that this protocol can be applied to future surveys in similar settings. In addition to determining the ecological zones requiring mass drug administration interventions, we aim to provide precise estimates of the prevalence of these diseases. Methods A school–based cross-sectional design will be applied for the nationwide survey across Sudan. The survey is designed to cover all districts in every state. We have divided each district into 3 different ecological zones depending on proximity to bodies of water. We will employ a probability-proportional-to-size sampling method for schools and systematic sampling for student selection to provide adequate data regarding the prevalence for schistosomiasis and STHs in Sudan at the state level. A total of 108,660 students will be selected from 1811 schools across Sudan. After the survey is completed, 391 ecological zones will be mapped out. To carry out the survey, 655 staff members were recruited. The feces and urine samples are microscopically examined by the Kato-Katz method and the sediment smears for helminth eggs respectively. For quality control, a minimum of 10% of the slides will be rechecked by the federal supervisors in each state and also 5% of the smears are validated again within one day by independent supervisors. Discussion This nationwide mapping is expected to generate important epidemiological information and indicators about schistosomiasis and STHs that will be useful for monitoring and evaluating the control
Luiz Arthur Calheiros Leite
Full Text Available BACKGROUND: Schistosomiasis mansoni is an endemic parasitic disease and a public health problem in Northeast Brazil. In some patients, hepatic abnormalities lead to periportal fibrosis and result in the most severe clinical form, hepatosplenic schistosomiasis. This study aimed to evaluate whether abnormal blood coagulation and liver function tests in patients with hepatosplenic schistosomiasis (n = 55 correlate with the severity of their periportal fibrosis. METHODOLOGY/PRINCIPAL FINDINGS: Blood samples were used for liver function tests, hemogram and prothrombin time (International Normalized Ratio, INR. The blood coagulation factors (II, VII, VIII, IX and X, protein C and antithrombin IIa (ATIIa, plasminogen activator inhibitor 1 (PAI-1 and D-dimer were measured by photometry or enzyme linked immunosorbent assay. Hyperfibrinolysis was defined on the basis of PAI-1 levels and a D-dimer concentration greater than a standard cut-off of 483 ng/mL. Standard liver function tests were all abnormal in the patient group compared to healthy controls (n = 29, including raised serum transaminases (p<0.001 and lower levels of albumin (p = 0.0156. Platelet counts were 50% lower in patients, while for coagulation factors there was a 40% increase in the INR (p<0.001 and reduced levels of Factor VII and protein C in patients compared to the controls (both p<0.001. Additionally, patients with more advanced fibrosis (n = 38 had lower levels of protein C compared to those with only central fibrosis (p = 0.0124. The concentration of plasma PAI-1 in patients was one-third that of the control group (p<0.001, and D-dimer levels 2.2 times higher (p<0.001 with 13 of the 55 patients having levels above the cut-off. CONCLUSION/SIGNIFICANCE: This study confirms that hemostatic abnormalities are associated with reduced liver function and increased liver fibrosis. Of note was the finding that a quarter of patients with hepatosplenic schistosomiasis and
Favre, Tereza C; Pereira, Ana P B; Galvão, Aline F; Zani, Luciana C; Barbosa, Constança S; Pieri, Otávio S
Since its beginning in 1999, the Schistosomiasis Control Program within the Unified Health System (PCE-SUS) has registered a cumulative coverage of just 20% of the population from the Rainforest Zone of Pernambuco (ZMP), northeast Brazil. This jeopardizes the accomplishment of the minimum goal of the Fifty-Fourth World Health Assembly, resolution WHA54.19, of providing treatment for schistosomiasis and soil-transmitted helminthiases (STH) to 75% of school-aged children at risk, which requires attending at least 166,000 residents in the 7-14 age range by year 2010 in that important endemic area. In the present study, secondary demographic and parasitological data from a representative municipality of the ZMP are analyzed to provide evidence that the current, community-based approach to control schistosomiasis and STH is unlikely to attain the WHA-54.19 minimum goal and to suggest that school-based control actions are also needed. Data available on the PCE-SUS activities related to diagnosis and treatment of the population from the study municipality were obtained from the State Secretary of Health of Pernambuco (SES/PE) for 2002-2006, complemented by the Municipal Secretary of Health (SMS) for 2003-2004. Data from a school-based stool survey carried out by the Schistosomiasis Reference Service of the Oswaldo Cruz Foundation (SRE/Fiocruz) in 2004 were used to provide information on infection status variation among school-aged children (7-14 years). According to the SES, from 2004 to 2006, only 2,977 (19.5%) of the estimated 15,288 residents of all ages were examined, of which 396 (13.3%) were positive for Schistosoma mansoni. Among these, only 180 (45.5%) were treated. According to the SMS, of the 1,766 examined in the 2003-2004 population stool survey 570 (32.3%) were children aged 7-14 years. One year later, the SRE/Fiocruz school survey revealed that the infection status among those children remained unchanged at 14%-15% prevalence. By 2006, the school
Full Text Available With the aim of exploring the usefulness of spatial analysis in the formulation of a strategy for schistosomiasis japonica control in different environmental settings, a population-based database was established in Dangtu county, China. This database, containing the human prevalence of schistosomiasis at the village level from 2001 to 2004, was analyzed by directional trend analysis supported with ArcGIS 9.0 to select the optimum predictive approach. Based on the approach selected, different strata of prevalence were classified and the spatial distribution of human infection with Schistosoma japonicum was estimated. The second-order ordinary kriging approach of spatial analysis was found to be optimal for prediction of human prevalence of S. japonicum infection. The mean prediction error was close to 0 and the root-mean-square standardised error was close to 1. Starting with the different environmental settings for each stratum of transmission, four areas were classified according to human prevalence, and different strategies to control transmission of schistosomiasis were put forward. We conclude that the approach to use spatial analysis as a tool to predict the spatial distribution of human prevalence of S. japonicum infection improves the formulation of strategies for schistosomiasis control in different environmental settings at the county level.
Xianyi, Chen; Liying, Wang; Jiming, Cai; Xiaonong, Zhou; Jiang, Zheng; Jiagang, Guo; Xiaohua, Wu; Engels, D; Minggang, Chen
China has been carrying out large-scale schistosomiasis control since the mid-1950s, but in the early 1990s, schistosomiasis was still endemic in eight provinces. A World Bank Loan Project enabled further significant progress to be made during the period 1992-2001. The control strategy was focused on the large-scale use of chemotherapy -- primarily to reinforce morbidity control -- while at the same time acting on transmission with the ultimate goal of interrupting it. Chemotherapy was complemented by health education, chemical control of snails and environmental modification where appropriate. A final evaluation in 2002 showed that infection rates in humans and livestock had decreased by 55% and 50%, respectively. The number of acute infections and of individuals with advanced disease had also significantly decreased. Although snail infection rates continued to fluctuate at a low level, the densities of infected snails had decreased by more than 75% in all endemic areas. The original objectives of the China World Bank Loan Project for schistosomiasis control had all been met. One province, Zhejiang, had already fulfilled the criteria for elimination of schistosomiasis by 1995. The project was therefore a success and has provided China with a sound basis for further control.
Wang, Shuqi; Hu, Wei
Schistosomiasis, caused by dioecious flatworms in the genus Schistosoma, is torturing people from many developing countries nowadays and frequently leads to severe morbidity and mortality of the patients. Praziquantel based chemotherapy and morbidity control for this disease adopted currently necessitate viable and efficient diagnostic technologies. Fortunately, those “-omics” researches, which rely on high-throughput experimental technologies to produce massive amounts of informative data, have substantially contributed to the exploitation and innovation of diagnostic tools of schistosomiasis. In its first section, this review provides a concise conclusion on the progresses pertaining to schistosomal “-omics” researches to date, followed by a comprehensive section on the diagnostic methods of schistosomiasis, especially those innovative ones based on the detection of antibodies, antigens, nucleic acids, and metabolites with a focus on those achievements inspired by “-omics” researches. Finally, suggestions about the design of future diagnostic tools of schistosomiasis are proposed, in order to better harness those data produced by “-omics” studies. PMID:25018752
Swartz, Scott J; De Leo, Giulio A; Wood, Chelsea L; Sokolow, Susanne H
Schistosomiasis - a parasitic disease that affects over 200 million people across the globe - is primarily transmitted between human definitive hosts and snail intermediate hosts. To reduce schistosomiasis transmission, some have advocated disrupting the schistosome life cycle through biological control of snails, achieved by boosting the abundance of snails' natural predators. But little is known about the effect of parasitic infection on predator-prey interactions, especially in the case of schistosomiasis. Here, we present the results of laboratory experiments performed on Bulinus truncatus and Biomphalaria glabrata snails to investigate: (i) rates of predation on schistosome-infected versus uninfected snails by a sympatric native river prawn, Macrobrachium vollenhovenii, and (ii) differences in snail behavior (including movement, refuge-seeking and anti-predator behavior) between infected and uninfected snails. In predation trials, prawns showed a preference for consuming snails infected with schistosome larvae. In behavioral trials, infected snails moved less quickly and less often than uninfected snails, and were less likely to avoid predation by exiting the water or hiding under substrate. Although the mechanism by which the parasite alters snail behavior remains unknown, these results provide insight into the effects of parasitic infection on predator-prey dynamics and suggest that boosting natural rates of predation on snails may be a useful strategy for reducing transmission in schistosomiasis hotspots. © 2015. Published by The Company of Biologists Ltd.
Mar 3, 2012 ... Objective: to provide baseline epidemiological data (prevalence, intensity of infection and Knowledge) on urinary Schistosomiasis in a new focus behind mount cameroon. Design: longitudinal Study. Setting: Eight (8) primary Schools in munyenge health district, fako division, South west cameroon.
S. Sow (Seydou)
textabstractSchistosomiasis (bilharzia) is one of the major parasitic diseases in the world, ranking second only to malaria in terms of its socio-economic and public health importance in tropical and subtropical areas (WHO, 1985; WHO, 2002). At least 200 million people are infected and 600 million
Full Text Available We reviewed the early literature and maps of the occurrence of urogenital schistosomiasis (bilharzia in the Eastern Cape, South Africa from the 1860s until its decline from about 1900 and reappearance in 2002. Although this decline in transmission has received little attention to date, clinical descriptions of the disease over this period indicate that infection was common, probably patchy, although sometimes with severe morbidity. The long period of quiescence between 1900 and 2002 is thought to be as a result of several factors, but primarily because of the impact of the area’s cold winters and drought-prone climate on the survival and reproduction of both the snail intermediate host Bulinus africanus and the intramolluscan stages of the parasite. The concept of an outbreak area is invoked to describe the occurrence of intense urogenital schistosomiasis transmission in localised areas for relatively short periods of up to 35 years in this the southernmost part of its range in Africa, a suboptimal environment for transmission.
Schneider, C R; Kitikoon, V; Sornmani, S; Thirachantra, S
Of 103 water buffalo (Bubalus bubalis) examined on Khong Island by means of the M.I.F.C. and hatching techniques, none were passing eggs resimbling those of the Mekong schistosome. One buffalo calf was infected with Orientobilharzia harinasutai and another with Schistosoma spindale; this is the first time these parasites have been reported from Laos. Since the buffalo that were examined had constant and year-round access to a part of the Mekong River that has been shown to be a site of heavy transmission of schistosomiasis to humans and dogs, it was considered that the buffalo would have acquired the infection with the human Mekong schistosome if this were possible. In the absence of buffalo necropsies, and since no eggs of the Mekong schistosome were detected in the stools of these animals, we assumed that they had either not become infected with this parasite or, if they had, that the infections did not produce eggs in the faeces which were detectable by the methods employed. On the basis of our examinations, it would not seem that domestic water buffalo are involved as reservoirs in the epidemiology of human schistosomiasis on Khong Island.
Suellen D'Arc dos Santos Oliveira
Full Text Available Schistosomiasis, classified by the World Health Organization as a neglected tropical disease, is an intravascular parasitic disease associated to a chronic inflammatory state. Evidence implicating inflammation in vascular dysfunction continues to mount, which, broadly defined, reflects a failure in the control of intracellular Ca2+ and consequently, vascular contraction. Therefore, we measured aorta contraction induced by 5-hydroxytryptamine (5-HT and endothelin-1 (ET-1, two important regulators of vascular contraction. Isometric aortic contractions were determined in control and Schistosoma mansoni-infected mice. In the infected animals, 5-HT induced a 50% higher contraction in relation to controls and we also observed an increased contraction in response to Ca2+ mobilisation from sarcoplasmic reticulum. Nevertheless, Rho kinase inhibition reduced the contraction in response to 5-HT equally in both groups, discarding an increase of the contractile machinery sensitivity to Ca2+. Furthermore, no alteration was observed for contractions induced by ET-1 in both groups. Our data suggest that an immune-vascular interaction occurs in schistosomiasis, altering vascular contraction outside the mesenteric portal system. More importantly, it affects distinct intracellular signalling involved in aorta contraction, in this case increasing 5-HT receptor signalling.
Full Text Available "nCentral nervous system involvement arising from schistosomiasis is uncommon. It may be produced most frequently by Schistosoma japonicum infection, but reports of S. mansoni presenting as an intracerebral mass lesion are particularly rare. The authors describe the case of a 35-year-old woman with a 3-month history of partial epileptic seizures and headaches. She immigrated to Egypt 4 years ago and had worked in Iraq for 2 years after the immigration. The patient's general physical and neurological examinations were unremarkable. Magnetic resonance (MR imaging revealed an enhancing lesion with surrounding edema and mild mass effect in the left frontal lobe. A stereotactic brain biopsy demonstrated intraparenchymal granulomas surrounding S. mansoni eggs. S. mansoni was identified by stool examination. Prednisone (1 mg/kg per day for 1 week, with gradual withdrawal during the following 3 weeks and praziquantel (2 doses at 20 mg/kg per day therapy was initiated. The patient's symptoms resolved following medical treatment and the follow-up MR imaging yielded normal findings. This case is the rare imported case of cerebral schistosomiasis in China and the neuroschistosomiasis should be considered as the patient lived in a region in which this disease is endemic.
Full Text Available In spite of various control measures and eradication methods that have been in progress, schistosomiasis still prevails as one of the most prevalent debilitating parasitic diseases, typically affecting the poor and the underprivileged that are predominantly concentrated in sub-Saharan Africa. The parasitic schistosome blood fluke responsible for causing the disease completes its complex developmental cycle in two hosts: humans and freshwater snails, where they physically undergo gross modifications to endure the different conditions associated with each host. Just like any other organism, the worm possesses mechanisms that help them respond to environmental insults. It has been hypothesized that a special class of proteins known as Universal Stress Proteins (USPs are up-regulated during sudden environmental changes, thus assisting the worm to tolerate the unfavourable conditions associated with its developmental cycle. The position of praziquantel as the drug of choice against all schistosome infections has been deemed vulnerable due to mounting concerns over drug pressure and so the need for alternative treatment is now a matter of urgency. Therefore, this review seeks to explore the associations and possible roles of USPs in schistosomiasis as well as the functioning of these proteins in the schistosomulae stage in order to develop new therapeutic interventions against this disease.
Liao, Xian-chao; Huang, Wen-hui; Wu, Guang-cui
To understand the changes of epidemic situation of schistosomiasis in Shashi District, Jingzhou City. From 2005 to 2010, each year, from April to May, thestatus of Oncomelania snails were investigate by using the systematic sampling approach; in October, the inhabitants aged over 6 years were screened by indirect hemagglutination assay (IHA) and the positive persons received the etiological examination (Kato-Katz technique). All the farm cattle in pens were examined by using the plastic cup jacking hatching method. The data of control measures, and the nature and society data were collected annually. All the data were analyzed systematically. From 2005-2010, the positive rate of blood tests was from 16.47% to 26.84%, assuming an ascend trend; the positive rate of stool examinations was from 2.13% to 4.44%, assuming a downward trend; the infection rate of cattle was from 1.56% to 18.00%, assuming a downward trend in volatility. The area with snails, the appearance rate of frames with living snails, and the average density of living snails assumed ascend trends. The prevalence of schistosomiasis presents a downward trend in volatility, and the snail status assumes a ascend trend. Therefore, the prevention and control measures still should be strengthened.
Muhumuza, Simon; Olsen, Annette; Katahoire, Anne
BACKGROUND: Sustaining high uptake of praziquantel is key for long-term control of schistosomiasis. During mass treatment in 2013, we randomized 12 primary schools into two groups; one group received education messages for schistosomiasis prevention for two months prior to mass treatment, while...... the other, in addition to the education messages, received a pre-treatment snack shortly before mass treatment. The uptake of praziquantel in the snack schools was 94 % compared to 79 % in the non-snack schools. During mass treatment in 2014, no snack was provided. We compared the uptake of praziquantel......, the difference in the geometric mean intensity of S. mansoni infection in both the snack and non-snack schools was not statistically significant; 38.3 eggs per gram of stool (epg) and 145.7 epg (p = 0.197) and 78.4 epg and 322.5 epg (p = 0.120), respectively. CONCLUSION: Our results show that in absence of food...
David J. Wyler
Full Text Available Morbidity in schistosomiasis mansoni occurs primaryly as a result of the complications of hepatic fibrosis. Yet, the pathogenesis of schistosomal hepatic fibrosis is poorly understood. The fact that hepatic egg granuloma is the hallmark of this infection suggests a potential role for granulomatous inflamation in hepatic fibrogenesis. Our studies in a murine schistosomiasis model indicate that hepatic granuloma cells secrete a variety of fibrogenic cytokines that may initiate the scarring process. Among these cytokines, we identified a novel protein that we designated fibroplast stimulating factor-1 (FsF-1. FsF-1 is a lymphokine that can stimulate fibroplast growth and matrix synthesis. A notable feature of hepatic fibrosis in this model is that production of FsF-1 and other granuloma-derived fibrogenic cytokines is down-regulated in chronic infection, an event that may be under immunological control. The spontaneous reduction of FsF-1 secretion presumably accounts for reduced scar formation late in infection of mice. In the context of relevant clinical studies, our findings engender the hypothesis that Symmer's fibrosis may develop in a small suppopulation of individuals as a result of immunogenetically-determined dysregulation of fibrogenic cytokine production.
Schall, V T
Some municipalities in Brazil have been requesting orientation for the implementation of health education programs related to the control of schistosomiasis. This demand was based on experiences in the development of health education researches, strategies and materials for school-age children, involving the communities and secretaries of health and education. Motivated by this request and the recently implemented plan of health services (Unified Health System-Sistema Unico de Saúde-SUS) that gives autonomy to the municipalities to utilize health resources and services in Brazil, this paper presents an interactive perspective of planning health education research and programs. The purpose of this perspective is to stimulate a reflection on the needs and actions of institutions and people involved in health education research and/or programs to obtain sustainability, commitment and effectiveness--not only in the control of schistosomiasis, but also in the improvement of environmental conditions, quality of life and personal health. This perspective comprises interaction among three levels related to health education programs: the decision level, the executive level and the beneficiary level. The needs and lines of action at each of these levels are discussed, as well as the ways in which they can interact with each other. This proposal may lead to useful interactive ways of planing, organizing, executing and evaluating health education research and/or program, not only towards the prevention and control of the disease at stake, but also to promote health in general.
Virgínia T Schall
Full Text Available Some municipalities in Brazil have been requesting orientation for the implementation of health education programs related to the control of schistosomiasis. This demand was based on experiences in the development of health education researches, strategies and materials for school-age children, involving the communities and secretaries of health and education. Motivated by this request and the recently implemented plan of health services (Unified Health System - Sistema Único de Saúde - SUS that gives autonomy to the municipalities to utilize health resources and services in Brazil, this paper presents an interactive perspective of planning health education research and programs. The purpose of this perspective is to stimulate a reflection on the needs and actions of institutions and people involved in health education research and/or programs to obtain sustainability, commitment and effectiveness - not only in the control of schistosomiasis, but also in the improvement of environmental conditions, quality of life and personal health. This perspective comprises interaction among three levels related to health education programs: the decision level, the executive level and the beneficiary level. The needs and lines of action at each of these levels are discussed, as well as the ways in which they can interact with each other. This proposal may lead to useful interactive ways of planing, organizing, executing and evaluating health education research and/or program, not only towards the prevention and control of the disease at stake, but also to promote health in general.
Savioli, L; Albonico, M; Engels, D; Montresor, A
In the last two decades important progress has been made in the understanding the epidemiology and the disease burden of schistosomiasis and soil-transmitted nematodes infection. In addition, practical tools for disease control have been developed and a strategy for the prevention and control of morbidy of schistosomaisis and soil-transmitted nematodes infection has been endorsed by the World Health Organization. This paper presents the recent progress in the prevention and control of these infections: the estimates of chronic and subtle morbidity in high risk groups and the evidence that these chronic and severe sequelae of infections can be reversed by appropriate treatment; the use of anthelminthic drugs during pregnancy and lactation; the relevance to control morbidity due to these infections also in pre-school children; the efficacy of anthelminthic drugs and the possible threat of drug resistance; price, quality and accessibility of treatment by delivering drugs through the school system and ways of reaching also non-enrolled school-age children. Finally, the strategy, targets and recommendations of the World Health Organization for the control of schistosomiasis and soil-transmitted nematodes infection are described.
Ndekha, Addmore; Hansen, Ebba Holme; Mølgaard, Per; Woelk, Godfrey; Furu, Peter
A schistosomiasis control project was undertaken from 1994 to 1998 in Guruve District, Zimbabwe, based on the active involvement of local communities in the growing and application of the molluscicidal plant Phytolacca dodecandra as a supplement to other control measures such as chemotherapy and health education. The berries of P. dodecandra are highly molluscicidal to the intermediate host snails of schistosomiasis and is rapidly degradable in water. It was observed that plant care fluctuated during the study period. Only a few households participated in snail control activities, although 97% of respondents in a baseline survey had stated a willingness to take part. This invoked an investigation to explore the reality from a user perspective. Focus group discussions, semi-structured interviews and observations were used to solicit information. In spite of a cultural inclination for collective work, many reasons for low-level involvement emerged, inter alia the low perceived value of the project, demands for tangible benefits, inaccessible fields and weak leadership. This study shows that community participation is a complex process upon which a multiplicity of social and cultural determinants have an impact. If community participation is to become successful in development programmes it ought to be viewed as a mutual learning process where obstacles are identified and discussed and solutions shared among community members and project staff.
Sayed, Fatma Galal; Alsalahy, Mohammed; Abd-el-Kader, Mohammed Sayed; Abdalla, Osama Hussein; Ahmed, Samar S
Schistosomiasis is a public health problem in Egypt. To detect the prevalence of schistosomiasis in Qena Governorate, 1601 urine and stool samples of patients attending Qena General Hospital were examined of whom 1601 patients had urinary symptoms and 893 patients had dysentery and bloody stool. Sheets were filled out on each patient. Also, a total of 7590 Bulinus truncatus and Biomphalaria alexandrina snails were collected from water bodies in Qena Governorate. The overall prevalence of S. haematobium was 13.9%; with maximum among 6-18 year-old age group and higher in males than in females. Risk factors for S. haematobium infection were this age group; particularly males. However, males swim and play in water bodies and women wash cloths and utensils there, and children swimming or playing in canals. The S. haematobium peak of infection was in winter correlated with the highest prevalence in Dandara City, Qena City, Awlad-Amr and El Hijarat. S. mansoni were negative in the examined individuals. The infective rate among snails was 1.82% in B. truncatus and 0.0% among B. alexandrina and M. tuberculata.
Matthew F. Rose
Full Text Available Schistosomiasis is the second most socioeconomically devastating parasitic disease worldwide, affecting over 240 million people in 77 countries on 5 continents and killing 300,000 people annually in sub-Saharan Africa alone. Neuroschistosomiasis is caused by granuloma formation around eggs that lodge in the CNS, with Schistosoma mansoni and Schistosoma haematobium usually affecting the spinal cord and Schistosoma japonicum causing most reported cerebral disease. We report a case of a previously healthy 25-year-old woman native to the United States who presented with a single generalized tonic–clonic seizure without other neurologic symptoms four years after spending a semester in Ghana where she went swimming once in a river. Brain MRI showed areas of signal abnormality and mottled nodular linear enhancement in the left temporal and right posterior temporal/parietal lobes and right cerebellum without mass effect. A biopsy of the left temporal lesion showed prominent granulomas with dense mixed inflammatory infiltrates composed of eosinophils, plasma cells, and lymphocytes surrounding refractile egg shells containing characteristic embryonal cells and von Lichtenberg's envelope and displaying the pathognomonic spine shape of S. mansoni. Serum ELISA and antibody immunoblots confirmed exposure to S. mansoni. In summary, we describe the atypical combination of cerebral schistosomiasis due to S. mansoni, after a prolonged interval of four years, from a single known exposure.
Liu, Yang; Zhong, Bo; Wu, Zi-Song; Liang, Song; Qiu, Dong-Chuan; Ma, Xiao
Schistosomiasis remains a major public health concern in China. Since 2004, an integrated strategy was developed to control the transmission of Schistosoma japonicum in China. However, the long-term effectiveness of this integrated strategy for the interruption of schistosomiasis transmission remains unknown in the mountainous and hilly regions of China until now. This longitudinal study aims to evaluate the effectiveness of the integrated strategy on transmission interruption of schistosomiasis in Sichuan Province from 2005 through 2014. The data regarding replacement of bovines with machines, improved sanitation, access to clean water, construction of public toilets and household latrines, snail control, chemotherapy, and health education were captured from the annual report of the schistosomiasis control programmes in Sichuan Province from 2005 to 2014, and S. japonicum infection in humans, bovines and snails were estimated to evaluate the effectiveness of the integrated strategy. During the 10-year period from 2005 through 2014, a total of 536 568 machines were used to replace bovines, and 3 284 333 household lavatories and 15 523 public latrines were built. Tap water was supplied to 19 116 344 residents living in the endemic villages. A total of 230 098 hm 2 snail habitats were given molluscicide treatment, and 357 233 hm 2 snail habitats received environmental improvements. There were 7 268 138 humans and 840 845 bovines given praziquantel chemotherapy. During the 10-year study period, information, education and communication (IEC) materials were provided to village officers, teachers and schoolchildren. The 10-year implementation of the integrated strategy resulted in a great reduction in S. japonicum infection in humans, bovines and snails. Since 2007, no acute infection was detected, and no schistosomiasis cases or infected bovines were identified since 2012. In addition, the snail habitats reduced by 62.39% in 2014 as compared to that in 2005, and no S
Full Text Available Abstract Background Schistosomiasis is a parasitic infection that continues to be a major public health problem in many developing countries being responsible for an estimated burden of at least 1.4 million disability-adjusted life years (DALYs in Africa alone. Importantly, morbidity due to schistosomiasis has been greatly reduced in some parts of the world, including Zanzibar. The Zanzibar government is now committed to eliminate urogenital schistosomiasis. Over the next 3–5 years, the whole at-risk population will be administered praziquantel (40 mg/kg biannually. Additionally, snail control and behaviour change interventions will be implemented in selected communities and the outcomes and impact measured in a randomized intervention trial. Methods/Design In this 5-year research study, on both Unguja and Pemba islands, urogenital schistosomiasis will be assessed in 45 communities with urine filtration and reagent strips in 4,500 schoolchildren aged 9–12 years annually, and in 4,500 first-year schoolchildren and 2,250 adults in years 1 and 5. Additionally, from first-year schoolchildren, a finger-prick blood sample will be collected and examined for Schistosoma haematobium infection biomarkers. Changes in prevalence and infection intensity will be assessed annually. Among the 45 communities, 15 were randomized for biannual snail control with niclosamide, in concordance with preventive chemotherapy campaigns. The reduction of Bulinus globosus snail populations and S. haematobium-infected snails will be investigated. In 15 other communities, interventions triggering behaviour change have been designed and will be implemented in collaboration with the community. A change in knowledge, attitudes and practices will be assessed annually through focus group discussions and in-depth interviews with schoolchildren, teachers, parents and community leaders. In all 45 communities, changes in the health system, water and sanitation infrastructure will
Knopp, Stefanie; Mohammed, Khalfan A; Ali, Said M; Khamis, I Simba; Ame, Shaali M; Albonico, Marco; Gouvras, Anouk; Fenwick, Alan; Savioli, Lorenzo; Colley, Daniel G; Utzinger, Jürg; Person, Bobbie; Rollinson, David
Schistosomiasis is a parasitic infection that continues to be a major public health problem in many developing countries being responsible for an estimated burden of at least 1.4 million disability-adjusted life years (DALYs) in Africa alone. Importantly, morbidity due to schistosomiasis has been greatly reduced in some parts of the world, including Zanzibar. The Zanzibar government is now committed to eliminate urogenital schistosomiasis. Over the next 3-5 years, the whole at-risk population will be administered praziquantel (40 mg/kg) biannually. Additionally, snail control and behaviour change interventions will be implemented in selected communities and the outcomes and impact measured in a randomized intervention trial. In this 5-year research study, on both Unguja and Pemba islands, urogenital schistosomiasis will be assessed in 45 communities with urine filtration and reagent strips in 4,500 schoolchildren aged 9-12 years annually, and in 4,500 first-year schoolchildren and 2,250 adults in years 1 and 5. Additionally, from first-year schoolchildren, a finger-prick blood sample will be collected and examined for Schistosoma haematobium infection biomarkers. Changes in prevalence and infection intensity will be assessed annually. Among the 45 communities, 15 were randomized for biannual snail control with niclosamide, in concordance with preventive chemotherapy campaigns. The reduction of Bulinus globosus snail populations and S. haematobium-infected snails will be investigated. In 15 other communities, interventions triggering behaviour change have been designed and will be implemented in collaboration with the community. A change in knowledge, attitudes and practices will be assessed annually through focus group discussions and in-depth interviews with schoolchildren, teachers, parents and community leaders. In all 45 communities, changes in the health system, water and sanitation infrastructure will be annually tracked by standardized questionnaire
Brouwer Kimberly C
Full Text Available Abstract Background Helminth infection rates in grade three children are used as proxy indicators of community infection status and to guide treatment strategies in endemic areas. However knowledge, attitudes and practices (KAP of this target age group (8-10 years in relation to schistosomiasis, soil transmitted helminthiasis (STHs and malaria is not known at a time when integrated plasmodium - helminth control strategies are being advocated. This study sought to assess KAP of grade 3 children in relation to schistosomiasis, STHs and malaria in order to establish an effective school based health education for disease transmission control. Methods Grade 3 children (n = 172 attending four randomly selected primary schools (one in rural and 3 in the commercial farming areas in Zimbabwe were interviewed using a pre-tested interviewer administered questionnaire. The urine filtration technique was used to determine S. haematobium infection status. Infection with S. mansoni and STHs was determined using a combination of results from the Kato Katz and formol ether concentration techniques. P. falciparum was diagnosed by examination of Giemsa stained thick blood smears. Results It was observed that 32.0%, 19.2% and 4.1% of the respondents had correct knowledge about the causes of schistosomiasis, malaria and STHs, respectively, whilst 22.1%, 19.2% and 5.8% knew correct measures to control schistosomiasis, malaria and STHs. Sixty-two percent and 44.8% did not use soap to wash hands after toilet and before eating food respectively, whilst 33.1% never wore shoes. There were no functional water points and soap for hand washing after toilet at all schools. There was a high prevalence distribution of all parasites investigated in this study at Msapa primary school - S. haematobium (77.8%, S. mansoni (33.3% hookworms (29.6% and P. falciparum (48.1%. Reports that participant had suffered from schistosomiasis and malaria before were significant predictors of
Ferreira, Rita de Cassia dos Santos; Montenegro, Silvia Maria Lucena; Domingues, Ana Lucia Coutinho; Bandeira, Angela Pontes; Silveira, Carlos Antonio da Mota; Leite, Luiz Arthur Calheiros; Pereira, Clara de Almeida; Fernandes, Izolda Moura; Mertens, Alessandra Brainer; Almeida, Milena Oliveira
It is suggested that interleukin (IL)-13 and transforming growth factor (TGF)-beta play a role in the pulmonary vascular changes found in animal models of schistosomiasis. The aim of this study was to assess and compare the serum levels of total TGF-beta and IL-13 of patients with schistosomiasis with pulmonary arterial hypertension (PAH) and patients with schistosomiasis without PAH. 34 patients from the schistosomiasis outpatient clinic of the Hospital das Clinicas, Recife, Pernambuco, Brazil, without PAH assessed by echocardiography and 34 patients from the Reference Centre of Pulmonary Hypertension of Pronto Socorro Cardiológico de Pernambuco, Recife, Brazil with PAH, confirmed by right heart catheterization, were enrolled on the study. Both groups presented with schistosomal periportal fibrosis after abdominal ultrasound. Serum levels of TGF-beta1 and IL-13 were determined by ELISA. Student t test to independent samples, Mann-Whitney test to nonparametric variables, Pearson correlation test for correlation analyses and Fisher Chi-squared test to compare categorical analyses were used. The median value of TGF-beta1 was significantly higher in patients with PAH (22496.9 pg/ml, interquartile range [IR] 15936.7 - 32087.8) than in patients without PAH (13629.9 pg/ml, IR: 10192.2- 22193.8) (p = 0.006). There was no difference in the median value of IL-13 in the group with Sch-PAH compared to patients without Sch-PAH (p > 0.05). Our results suggest that TGF-beta possibly plays a role in the pathogenesis of schistosomiasis-associated PAH.
Full Text Available Schistosomiasis remains a public health major problem and little is known in many areas, mainly in Sub-Saharan Africa.To assess the burden and risk factors of schistosomiasis and intestinal parasitic helminthes in the children of Cubal, Angola, and to compare different diagnostic approaches for urinary schistosomiasis under field conditions.A cross-sectional study was conducted. Urine and faeces samples of school children were microscopically studied. A random sample of children was obtained from an alphabetically arranged list of children, taking one of two children. Urine dipstick, colorimetric test and macrohaematuria were considered as indirect diagnostic methods and compared to direct urine examination. Possible risk factors for the infection were sex, age, distance to the river and previous treatment with praziquantel; the assessment was performed using Chi-square test.A total of 785 (61.18% children showed S. haematobium eggs in urine; children living within 500 meters from the river had a higher odds for infection: Odds ratio 1.97 (1.45-2.7 CI 95%; urine dipstick showed sensitivity of 96% and specificity of 61.3%, with a positive predictive value; colorimetric test showed sensitivity of 52.5%, specificity of 74.6% and a positive predictive value of 77%. Proteinuria was present in 653 (51.1% children, being more frequent in children with S. haematobium in urine (75.2%; 32 of 191 stool samples (16% showed the presence of other intestinal parasites and 8 (4% for S. haematobium.Prevalence of urinary schistosomiasis in our study area is much higher than the national average, considering it as a high-risk community. Proximity to a source of water was a risk factor for the infection. Indirect tests, as urine dipstick and colorimetric test, were useful tools for diagnosis, due to ease of use and low cost. Proteinuria was a common finding, probably showing an early structural damage due to schistosomiasis in this group of children.
Full Text Available Abstract Background Acute schistosomiasis constitutes a rare but serious condition in individuals experiencing their first prepatent Schistosoma infection. To circumvent costly and time-consuming diagnostics, an early and rapid diagnosis is required. So far, classic diagnostic tools such as parasite microscopy or serology lack considerable sensitivity at this early stage of Schistosoma infection. To validate the use of a blood based real-time polymerase chain reaction (PCR test for the detection of Schistosoma DNA in patients with acute schistosomiasis who acquired their infection in various endemic regions we conducted a European-wide prospective study in 11 centres specialized in travel medicine and tropical medicine. Methods Patients with a history of recent travelling to schistosomiasis endemic regions and freshwater contacts, an episode of fever (body temperature ≥38.5°C and an absolute or relative eosinophil count of ≥700/μl or 10%, were eligible for participation. PCR testing with DNA extracted from serum was compared with results from serology and microscopy. Results Of the 38 patients with acute schistosomiasis included into the study, PCR detected Schistosoma DNA in 35 patients at initial presentation (sensitivity 92%. In contrast, sensitivity of serology (enzyme immunoassay and/or immunofluorescence assay or parasite microscopy was only 70% and 24%, respectively. Conclusion For the early diagnosis of acute schistosomiasis, real-time PCR for the detection of schistosoma DNA in serum is more sensitive than classic diagnostic tools such as serology or microscopy, irrespective of the region of infection. Generalization of the results to all Schistosoma species may be difficult as in the study presented here only eggs of S. mansoni were detected by microscopy. A minimum amount of two millilitre of serum is required for sufficient diagnostic accuracy.
Ejike, Cynthia Uchechukwu; Oluwole, Akinola Stephen; Mogaji, Hammed Oladeji; Adeniran, Adebiyi Abdulhakeem; Alabi, Oladimeji Michael; Ekpo, Uwem Friday
Schistosomiasis remains a public health problem in many regions of the world, including Nigeria. Current control strategy involves mass drug administration with praziquantel to the endemic population. To complement and sustain on-going preventive chemotherapy, we developed a health educational game named Schisto and Ladders™ and tested its potential for the control of schistosomiasis among schoolchildren living in Imala-Odo, a highly endemic community near Abeokuta, Nigeria. One hundred school children were randomly selected and divided into intervention and control groups through balloting. Their knowledge, attitudes and practices (KAP) concerning schistosomiasis transmission, control and prevention were assessed using structured questionnaires. Schisto and Ladders™ game were given to the intervention group and the popular Snake and Ladders™ game to the control group. Both games were played for 2 months under the supervision of their class teachers. A post-KAP assessment was carried out in both groups, including focus group discussions (FGDs) to investigate knowledge and the impact of the games. Knowledge about urinary schistosomiasis and its transmission significantly improved (P = 0.000) in the intervention group (68.0%) compared to the control group (8.0%). FGDs showed that the frequency of visits to dam water also significantly reduced (P = 0.048) in the intervention group (18.0%) compared to the control group (40.0%). There was a significant increase in knowledge regarding risk behaviours, prevention and control of schistosomiasis among the intervention group, but no new knowledge gained in the control group. This study demonstrates the potential of the health education game Schisto and Ladders™ for teaching basic health education and promoting behavioural changes among schoolchildren in endemic communities.
Sonder Gerard J
Full Text Available Abstract Background This study prospectively assessed the occurrence of clinical and subclinical schistosomiasis, strongyloidiasis, filariasis, and toxocariasis, and the screening value of eosinophilia in adult short-term travelers to helminth-endemic countries. Methods Visitors of a pre-travel health advice centre donated blood samples for serology and blood cell count before and after travel. Samples were tested for eosinophilia, and for antibodies against schistosomiasis, strongyloidiasis, filariasis, and toxocariasis. Previous infection was defined as seropositivity in pre- and post-travel samples. Recent infection was defined as a seroconversion. Symptoms of parasitic disease were recorded in a structured diary. Results Previous infection was found in 112 of 1207 subjects: schistosomiasis in 2.7%, strongyloidiasis in 2.4%, filariasis in 3.4%, and toxocariasis in 1.8%. Recent schistosomiasis was found in 0.51% of susceptible subjects at risk, strongyloidiasis in 0.25%, filariasis in 0.09%, and toxocariasis in 0.08%. The incidence rate per 1000 person-months was 6.4, 3.2, 1.1, and 1.1, respectively. Recent infections were largely contracted in Asia. The positive predictive value of eosinophilia for diagnosis was 15% for previous infection and 0% for recent infection. None of the symptoms studied had any positive predictive value. Conclusion The chance of infection with schistosomiasis, strongyloidiasis, filariasis, and toxocariasis during one short-term journey to an endemic area is low. However, previous stay leads to a cumulative risk of infection. Testing for eosinophilia appeared to be of no value in routine screening of asymptomatic travelers for the four helminthic infections. Findings need to be replicated in larger prospective studies.
Profiling Nonrecipients of Mass Drug Administration for Schistosomiasis and Hookworm Infections : A Comprehensive Analysis of Praziquantel and Albendazole Coverage in Community-Directed Treatment in Uganda
Chami, Goylette F.; Kontoleon, Andreas A.; Bulte, Erwin|info:eu-repo/dai/nl/141315245; Fenwick, Alan; Kabatereine, Narcis B.; Tukahebwa, Edridah M.; Dunne, David W.
Background. Repeated mass drug administration (MDA) with preventive chemotherapies is the mainstay of morbidity control for schistosomiasis and soil-transmitted helminths, yet the World Health Organization recently reported that less than one-third of individuals who required preventive
Wang, Xiaoli; Wang, Wei; Wang, Peng
Schistosomiasis is a neglected tropical parasitic disease of great public health significance worldwide. Currently, mass drug administration with praziquantel remains the major strategy for global schistosomiasis control programs. Since 2005, an integrated strategy with emphasis on infectious source control was implemented for the control of schistosomiasis japonica, a major public health concern in China, and pilot studies have demonstrated that such a strategy is effective to reduce the prevalence of Schistosoma japonicum infection in both humans and bovines. However, there is little knowledge on the long-term effectiveness of this integrated strategy for controlling schistosomiasis japonica. The aim of this study was to evaluate the long-term effectiveness of the integrated strategy for schistosomiasis control following the 10-year implementation, based on the data from the national schistosomiasis control program released by the Ministry of Health, People's Republic of China. In 2014, there were 5 counties in which the transmission of schistosomiasis japonica had not been interrupted, which reduced by 95.2% as compared to that in 2005 (105 counties). The number of schistosomiasis patients and acute cases reduced by 85.5 and 99.7% in 2014 (115,614 cases and 2 cases) as compared to that in 2005 (798,762 cases and 564 cases), and the number of bovines and S. japonicum-infected bovines reduced by 47.9 and 98% in 2014 (919,579 bovines and 666 infected bovines) as compared to that in 2005 (1,764,472 bovines and 33,736 infected bovines), respectively. During the 10-year implementation of the integrated strategy, however, there was a minor fluctuation in the area of Oncomelania hupensis snail habitats, and there was only a 5.6% reduction in the area of snail habitats in 2014 relative to in 2005. The results of the current study demonstrate that the 10-year implementation of the integrated strategy with emphasis on infectious source has greatly reduced schistosomiasis
Full Text Available Access to health care is a major requirement in improving health and fostering socioeconomic development. In the People's Republic of China (P.R. China, considerable changes have occurred in the social, economic, and health systems with a shift from a centrally planned to a socialist market economy. This brought about great benefits and new challenges, particularly for vertical disease control programs, including schistosomiasis. We explored systemic barriers in access to equitable and effective control of schistosomiasis.Between August 2002 and February 2003, 66 interviews with staff from anti-schistosomiasis control stations and six focus group discussions with health personnel were conducted in the Dongting Lake area, Hunan Province. Additionally, 79 patients with advanced schistosomiasis japonica were interviewed. The health access livelihood framework was utilized to examine availability, accessibility, affordability, adequacy, and acceptability of schistosomiasis-related health care.We found sufficient availability of infrastructure and human resources at most control stations. Many patients with advanced schistosomiasis resided in non-endemic or moderately endemic areas, however, with poor accessibility to disease-specific knowledge and specialized health services. Moreover, none of the patients interviewed had any form of health insurance, resulting in high out-of-pocket expenditure or unaffordable care. Reports on the adequacy and acceptability of care were mixed.There is a need to strengthen health awareness and schistosomiasis surveillance in post-transmission control settings, as well as to reduce diagnostic and treatment costs. Further studies are needed to gain a multi-layered, in-depth understanding of remaining barriers, so that the ultimate goal of schistosomiasis elimination in P.R. China can be reached.
Moné, Hélène; Holtfreter, Martha C; Allienne, Jean-François; Mintsa-Nguéma, Rodrigue; Ibikounlé, Moudachirou; Boissier, Jérôme; Berry, Antoine; Mitta, Guillaume; Richter, Joachim; Mouahid, Gabriel
This study concerns the first urinary schistosomiasis case observed in Corsica (France, Europe) occurring in a 12-year-old German boy. The aim was to identify the relationship between this Schistosoma haematobium infection and other schistosomes of the Schistosoma group with terminal-spined ova. Morphological and molecular analyses were conducted on the ova. The results showed that the schistosome responsible for the emergence of schistosomiasis in Corsica was due to S. haematobium introgressed by genes from S. bovis.
Background: Schistosomiasis, accounted among the neglected tropical diseases (NTDs), represents a major public health problem, particularly in Africa, where more than 95% of all the cases of the world are currently concentrated. The health consequences of Schistosoma infection are considerable. Apart from the known long-term complications of a chronic infection (e.g. portal hypertension, kidney failure, bladder cancer and sterility), schistosomiasis is a debilitating disease leading to anaemi...
Sousa-Figueiredo, José C; Basáñez, María-Gloria; Khamis, I Simba; Garba, Amadou; Rollinson, David; Stothard, J Russell
Urinary schistosomiasis is responsible for a variety of debilitating conditions; foremost perhaps are urinary tract pathologies (UTPs). Although portable ultrasonography can be used to detect UTPs visually, there is still a need for rapid morbidity assessment (henceforth referred to as RaMA) tools that can be deployed in the field during implementation, monitoring and evaluation of control programmes. We therefore aimed to determine associations between excreted urine-albumin, as measured using a HemoCue photometer, and UTPs, as detected by ultrasonography, in children and adults from an urinary schistosomiasis endemic area in Zanzibar. In a survey of 140 school-children of both sexes (aged 9 to 15 yr) and 47 adult males (> or =16 yr) on the island of Unguja, the prevalence of egg-patent urinary schistosomiasis was 36.4% (CI(95) 28.5-45.0%) and 46.8% (CI(95) 32.1-61.9%) (P = 0.14), and that of UTPs was 39.4% (CI(95) 31.0-48.3%) and 64.4% (CI(95) 48.8-78.1%) (P = 0.006), respectively. In school-children, raised urine-albumin concentrations (>40 mg/L) were associated, albeit non-significantly, with prevalence of infection (OR = 3.1, P = 0.070), but more specifically and significantly with the prevalence of micro-haematuria (OR = 76.7, Palbumin excretion was associated with UTPs, particularly lesions of the bladder wall (OR = 8.4, P = 0.013). Albuminuria showed promising diagnostic performance, especially in school-aged children with sensitivity of 63.3% and specificity of 83.1% at detecting lower UTPs, i.e. bladder-wall lesions (ultrasonography as 'gold standard'). This study indicates that albuminuria assays could be used as a RaMA tool for monitoring UTP prevalence during control programmes, as well as a tool for selecting those with more chronic bladder-wall lesions without resorting to ultrasonography.
José C Sousa-Figueiredo
Full Text Available Urinary schistosomiasis is responsible for a variety of debilitating conditions; foremost perhaps are urinary tract pathologies (UTPs. Although portable ultrasonography can be used to detect UTPs visually, there is still a need for rapid morbidity assessment (henceforth referred to as RaMA tools that can be deployed in the field during implementation, monitoring and evaluation of control programmes. We therefore aimed to determine associations between excreted urine-albumin, as measured using a HemoCue photometer, and UTPs, as detected by ultrasonography, in children and adults from an urinary schistosomiasis endemic area in Zanzibar.In a survey of 140 school-children of both sexes (aged 9 to 15 yr and 47 adult males (> or =16 yr on the island of Unguja, the prevalence of egg-patent urinary schistosomiasis was 36.4% (CI(95 28.5-45.0% and 46.8% (CI(95 32.1-61.9% (P = 0.14, and that of UTPs was 39.4% (CI(95 31.0-48.3% and 64.4% (CI(95 48.8-78.1% (P = 0.006, respectively. In school-children, raised urine-albumin concentrations (>40 mg/L were associated, albeit non-significantly, with prevalence of infection (OR = 3.1, P = 0.070, but more specifically and significantly with the prevalence of micro-haematuria (OR = 76.7, P<0.0001. In adults, elevated urine-albumin excretion was associated with UTPs, particularly lesions of the bladder wall (OR = 8.4, P = 0.013. Albuminuria showed promising diagnostic performance, especially in school-aged children with sensitivity of 63.3% and specificity of 83.1% at detecting lower UTPs, i.e. bladder-wall lesions (ultrasonography as 'gold standard'.This study indicates that albuminuria assays could be used as a RaMA tool for monitoring UTP prevalence during control programmes, as well as a tool for selecting those with more chronic bladder-wall lesions without resorting to ultrasonography.
Full Text Available Andreas N Mbah,1,2 Ousman Mahmud,1 Omotayo R Awofolu,2 Raphael D Isokpehi11Center for Bioinformatics and Computational Biology, Department of Biology, Jackson State University, Jackson, MS, USA; 2Department of Environmental Sciences, College of Agriculture and Environmental Sciences, University of South Africa, Pretoria, South AfricaBackground: Human schistosomiasis is a freshwater snail-transmitted disease caused by parasitic flatworms of the Schistosoma genus. Schistosoma haematobium, Schistosoma mansoni, and Schistosoma japonicum are the three major species infecting humans. These parasites undergo a complex developmental life cycle, in which they encounter a plethora of environmental signals. The presence of genes encoding the universal stress protein (USP domain in the genomes of Schistosoma spp. suggests these flatworms are equipped to respond to unfavorable conditions. Though data on gene expression is available for USP genes, their biochemical and environmental regulation are incompletely understood. The identification of additional regulatory molecules for Schistosoma. USPs, which may be present in the human, snail, or water environments, could also be useful for schistosomiasis interventions.Methods: We developed a protocol that includes a visual analytics stage to facilitate integration, visualization, and decision making, from the results of sequence analyses and data collection on a set of 13 USPs from S. mansoni and S. japonicum.Results: Multiple sequence alignment identified conserved sites that could be key residues regulating the function of USPs of the Schistosoma spp. Based on the consistency and completeness of sequence annotation, we prioritized for further research the gene for a 184-amino-acid-long USP that is present in the genomes of the three human-infecting Schistosoma spp. Calcium, zinc, and magnesium ions were predicted to interact with the protein product of the gene.Conclusion: Given that the initial effects of
Lee, Young-Ha; Jeong, Hoo Gn; Kong, Woo Hyun; Lee, Soon-Hyung; Cho, Han-Ik; Nam, Hae-Sung; Ismail, Hassan Ahmed Hassan Ahmed; Alla, Gibril Nouman Abd; Oh, Chung Hyeon; Hong, Sung-Tae
Purpose Schistosomiasis remains a major public health concern in Sudan, particularly Schistosoma haematobium infection. This study presents the disease-reduction outcomes of an integrated control program for schistosomiasis in Al Jabalain locality of White Nile State, Sudan from 2009 through 2011. Methods The total population of the project sites was 482,902, and the major target group for intervention among them was 78,615 primary school students. For the cross-sectional study of the prevalence, urine and stool specimens were examined using the urine sedimentation method and the Kato cellophane thick smear method, respectively. To assess the impacts of health education for students and a drinking water supply facility at Al Hidaib village, questionnaire survey was done. Results The overall prevalence for S. haematobium and S. mansoni at baseline was 28.5% and 0.4%, respectively. At follow-up survey after 6–9 months post-treatment, the prevalence of S. haematobium infection was reduced to 13.5% (95% CI = 0.331–0.462). A higher reduction in prevalence was observed among girls, those with moderately infected status (around 20%), and residents in rural areas, than among boys, those with high prevalence (>40%), and residents in urban areas. After health education, increased awareness about schistosomiasis was checked by questionnaire survey. Also, a drinking water facility was constructed at Al Hidaib village, where infection rate was reduced more compared to that in a neighboring village within the same unit. However, we found no significant change in the prevalence of S. mansoni infection between baseline and follow-up survey (95% CI = 0.933–6.891). Conclusions At the end of the project, the prevalence of S. haematobium infection was reduced by more than 50% in comparison with the baseline rate. Approximately 200,000 subjects had received either praziquantel therapy, health education, or supply of clean water. To consolidate the achievements of this
Sousa-Figueiredo, José C.; Basáñez, María-Gloria; Khamis, I. Simba; Garba, Amadou; Rollinson, David; Stothard, J. Russell
Background Urinary schistosomiasis is responsible for a variety of debilitating conditions; foremost perhaps are urinary tract pathologies (UTPs). Although portable ultrasonography can be used to detect UTPs visually, there is still a need for rapid morbidity assessment (henceforth referred to as RaMA) tools that can be deployed in the field during implementation, monitoring and evaluation of control programmes. We therefore aimed to determine associations between excreted urine-albumin, as measured using a HemoCue photometer, and UTPs, as detected by ultrasonography, in children and adults from an urinary schistosomiasis endemic area in Zanzibar. Methodology/Principal Findings In a survey of 140 school-children of both sexes (aged 9 to 15 yr) and 47 adult males (≥16 yr) on the island of Unguja, the prevalence of egg-patent urinary schistosomiasis was 36.4% (CI95 28.5–45.0%) and 46.8% (CI95 32.1–61.9%) (P = 0.14), and that of UTPs was 39.4% (CI95 31.0–48.3%) and 64.4% (CI95 48.8–78.1%) (P = 0.006), respectively. In school-children, raised urine-albumin concentrations (>40 mg/L) were associated, albeit non-significantly, with prevalence of infection (OR = 3.1, P = 0.070), but more specifically and significantly with the prevalence of micro-haematuria (OR = 76.7, P<0.0001). In adults, elevated urine-albumin excretion was associated with UTPs, particularly lesions of the bladder wall (OR = 8.4, P = 0.013). Albuminuria showed promising diagnostic performance, especially in school-aged children with sensitivity of 63.3% and specificity of 83.1% at detecting lower UTPs, i.e. bladder-wall lesions (ultrasonography as ‘gold standard’). Conclusion/Significance This study indicates that albuminuria assays could be used as a RaMA tool for monitoring UTP prevalence during control programmes, as well as a tool for selecting those with more chronic bladder-wall lesions without resorting to ultrasonography. PMID:19806223
Cao, Z-G; Zhao, Y-E; Lee Willingham, A; Wang, T-P
Schistosomiasis japonica, an endemic, zoonotic tropical parasitic disease caused by Schistosoma japonicum, remains an important public health concern in The People's Republic of China. Unlike other species of Schistosoma, over 40 species of wild and domestic animals can act as reservoir hosts of S. japonicum, which increases the difficulty for the control of this tropical disease. It is widely recognized that domestic animals, particularly water buffaloes and cattle, play an important role in the transmission of S. japonicum. Hence, since the 1950s when The People's Republic of China commenced fight against the disease, the control of animal schistosomiasis has been carried out almost synchronously with that of human schistosomiasis, such that great strides have been made over the past six decades. In this chapter, we review the history and current status of schistosomiasis control in domestic animals in The People's Republic of China. We thoroughly analyse the prevalence of domestic animal schistosomiasis at different stages of schistosomiasis control and the role of different species of domestic animals in transmission of the disease, summarize the control strategies and assess their effectiveness. Furthermore, the challenges ahead are discussed and recommendations for future direction are provided. Copyright © 2016 Elsevier Ltd. All rights reserved.
Cao, Zhi-guo; Wang, Tian-ping; Wu, Wei-duo; Zhang, Shi-qing; Lv, Da-bing; Fang, Guo-ren; Zhao, Feng; Ling, Xian-sheng; Sha, Jian-jun; Wang, Feng-feng; Zhu, Lei
To investigate the possibility of spread of snails and transmission of schistosomiasis japonica due to the construction of water transfer project from Yangtze River to Huaihe River. In order to understand the current endemic situation of schistosomiasis in the project area, the distribution of snails was surveyed by routine methods, level of anti-schistosome antibody in human sera was detected by indirect haemagglutination test (IHA), and the prevalence of schistosomiasis in cattle was detected by egg hatching method. The snail survival and reproduction were observed in Chaohu Lake area(experimental area) and a control area for one year. Snail density was high in two starting points, from where the water in Yangtze River will be directed to Huaihe River. In counties of Wuwei and Hexian, through which the project will be built, the positive rate of anti-schistosome antibody in residents was 22.11% (168/760) and 18.59% (37/199), schistosomiasis prevalence in cattle was 2.42% (9/371) and 0.2% (2/997), respectively. Schistosomiasis was also endemic in Juchao District of Chaohu City. Snails respectively from grassland and hilly area were collected and put in Chaohu Lake for breed and newborn snails were found one year later. During the egg-laying season, the survival rate of snails from grassland in 2 experiment areas and a control area was 11.3%-16.7%, 3.0%-20.8% and 4.7%-14.7% respectively (chi2 = 0.093, 0.760, P > 0.05; chi2 = 0.647, 0, P > 0.05), and that of snails from hilly area was 24.1%-44.4%, 37.8%-67.3% and 86.3%-93.1% respectively (chi2 = 9.575, 5.302, P < 0.05; chi2 = 56.863, 36.218, P < 0.05). There was no significant difference between the experimental area and the control area on the number of eggs in the ovaries of the same type female snails. The one-year observation reveals that the construction of the project might result in spread of snails and transmission of schistosomiasis japonica in the relevant areas.
Mouchet, F; Vera, C; Bremond, P; Devidas, A; Sellin, B
In two villages of the Aïr (Republic of Niger) the authors have found a Schistosoma haematobium overall prevalence of 24.1% at Timia and 43.5% at El Meki. At El Meki, the distribution of prevalences by age group accords to that which is usually found. The maximum is found in the 5-14 years age group and highest in men than in women. At Timia, the prevalence among young pupils is low, this seems to be due to the application of sanitary education measures. At El Meki, Bulinus truncatus rohlfsi, present in a permanent pool ("guelta") is the intermediate host of schistosomes. The role of this snail in the transmission of urinary schistosomiasis at Timia has not been demonstrated. The role of Bulinus senegalensis, found in both villages has yet to be proved.
Stecher, Chalotte Willemann; Kallestrup, Per; Kjetland, Eyrun Floerecke
and acquisition, and treatment could be a neglected chance of HIV prevention. This review summarizes current knowledge on epidemiology, clinical manifestations, diagnosis and treatment of MGS as a hypothesized risk factor for HIV transmission. Future research areas of global interest are suggested. METHODS: Pub...... association between MGS and HIV are urgently needed. Furthermore, field diagnostic tools should be developed and future mass treatment programs should include adults to reduce morbidity and prevent HIV acquisition. SYSTEMATIC REVIEW REGISTRATION NUMBER: CRD42015016252.......OBJECTIVES: Male genital schistosomiasis (MGS) is a neglected manifestation of Schistosoma haematobium infection with ignored implications on reproductive health and a differential diagnosis to sexually transmitted infections in endemic regions. MGS may have associations with HIV transmission...
Eridan M. Coutinho
Full Text Available Body, liver and spleen weights; histopathology of the liver, spleen and intestines; hepatic and serum soluble proteins changes were the parameters studied in undernourished Swiss albino mice experimentally infected with S. mansoni. Non-infected deficient animab had lower liver/body weight and spleen/body weight ratios as compared to the controls (22.60% casein group. Infected mice showed higher values regardless the type of diet. Undernourished infected subgroup showed a persistent exudative periovular reaction in the liver. Soluble hepatic proteins content and serum protein fractions appeared to be lower in the deficient infected mice. A significant difference was detected in the gammaglobulin fraction between infected and non-infected animals fed the control diet with higher values for the former. Our data suggest that the effects of malnutrition, per se, are sometimes more detrimental to the host than those due to Manson 's schistosomiasis.
Full Text Available Interactions between two species that result in reduced growth rates for both and extinction of one of the species are generally considered cases of asymmetric interspecific competition. Exploitative or interference competition is the usual mechanism invoked. Here we describe another mechanism producing the same result, named apparent competition through facilitation (ACF, observed between Melanoides tuberculata and Biomphalaria glabrata populations. The superior competitor actually gives some benefit to the other species, whose population becomes unstable with progressively increasing oscillations, leading to extinction. A model of ACF using difference equations suggests initial dynamics distinct from traditional interspecific competition. The dynamics of two freshwater snails in the field and in laboratory experiments suggest ACF, and these relations should be considered in studies of schistosomiasis control. ACF could occur in natural populations, but might have gone undetected because the final result is similar to traditional interspecific competition.
Holmen, Sigve Dhondup; Kleppa, Elisabeth; Lillebø, Kristine
Schistosoma haematobium causes female genital schistosomiasis (FGS), which is a poverty-related disease in sub-Saharan Africa. Furthermore, it is co-endemic with human immunodeficiency virus (HIV), and biopsies from genital lesions may expose the individual to increased risk of HIV infection....... However, microscopy of urine and hematuria are nonspecific and insensitive predictors of FGS and gynecological investigation requires extensive training. Safe and affordable diagnostic methods are needed. We explore a novel method of diagnosing FGS using computer color analysis of colposcopic images....... In a cross-sectional study on young women in an endemic area, we found strong associations between the output from the computer color analysis and both clinical diagnosis (odds ratio [OR] = 5.97, P
Muniz-Junqueira Maria Imaculada
Full Text Available We investigated the influence of Salmonella typhimurium load and specific antibodies on phagocytosis in schistosomiasis. Macrophages from Schistosoma mansoni-infected mice showed depressed capacity to increase the phagocytosis in the presence of a high bacterial load, due to a reduced involvement of these cells in phagocytosis and to a deficient ability to increase the number of phagocytosed bacteria. Normal and Salmonella-infected mice increased their phagocytic capacity when exposed to a high bacterial load. Antibody to Salmonella increased the phagocytic capacity of macrophages from Schistosoma-infected mice due to an increase in the number of bacteria phagocytosed but caused no modification in the number of macrophages engaged in phagocytosis. Our data indicate that macrophages from Schistosoma-infected mice work close to their functional limit, since no increase in phagocytosis was observed after increasing the bacterial load. Specific antibodies can improve their phagocytic capacity and, therefore, could help clearing concurrent infection.
Maria José Conceição
Full Text Available The study had the objective to evaluate the benefits of surgical indication for portal hypertension in schistosomiasis patients followed from 1985 to 2001. Schistosoma mansoni eggs were confirmed by at least six stool examinations or rectal biopsy. Clinical examination, abdominal ultrasonography, and digestive endoscopy confirmed the diagnosis of esophageal varices. A hundred and two patients, 61.3% male (14-53 years old were studied. Digestive hemorrhage, hypersplenism, left hypochondrial pain, abdominal discomfort, and hypogonadism were, in a decreasing order, the major signs and symptoms determining surgical indication. Among the surgical techniques employed, either splenectomy associated to splenorenal anastomosis or azigoportal desvascularization, esophageal gastric descompression and esophageal sclerosis were used. Follow-up of patients revealed that, independent on the technique utilized, a 9.9% of death occurred, caused mainly by digestive hemorrhage due to the persistence of post-treatment varices. The authors emphasize the benefits of elective surgical indication allowing a normal active life.
Saarnak, Christopher; Braae, Uffe Christian; Magnussen, Pascal
countries were identified. The co-endemicity dataset was then combined with modelled data on population density for 2015 derived from the WorldPop database (http://www.worldpop.org). We used the open source GIS software QGIS and GRASS to overlay the two datasets and identified the number of people living......The World Health Organisation (WHO) is aiming for elimination of schistosomiasis by 2020 through mass drug administration (MDA). However, the drug used for this, praziquantel, has been reported to cause dramatic side effects, even death, among people suffering from neurocysticercosis (NCC). Both...... diseases are presumed to be widely distributed on the continent, but the co-endemicity is unclear. We carried out a literature study of T. solium taeniosis/ cysticercosis in humans and porcine cysticercosis in pigs. Only epidemiological/clinical studies were included, qualitative questionnaire based...
Ciddio, Manuela; Mari, Lorenzo; Sokolow, Susanne H.; De Leo, Giulio A.; Casagrandi, Renato; Gatto, Marino
Schistosomiasis is a parasitic, water-related disease that is prevalent in tropical and subtropical areas of the world, causing severe and chronic consequences especially among children. Here we study the spatial spread of this disease within a network of connected villages in the endemic region of the Lower Basin of the Senegal River, in Senegal. The analysis is performed by means of a spatially explicit metapopulation model that couples local-scale eco-epidemiological dynamics with spatial mechanisms related to human mobility (estimated from anonymized mobile phone records), snail dispersal and hydrological transport of schistosome larvae along the main water bodies of the region. Results show that the model produces epidemiological patterns consistent with field observations, and point out the key role of spatial connectivity on the spread of the disease. These findings underline the importance of considering different transport pathways in order to elaborate disease control strategies that can be effective within a network of connected populations.
Tereza C Favre
Full Text Available BACKGROUND: Since its beginning in 1999, the Schistosomiasis Control Program within the Unified Health System (PCE-SUS has registered a cumulative coverage of just 20% of the population from the Rainforest Zone of Pernambuco (ZMP, northeast Brazil. This jeopardizes the accomplishment of the minimum goal of the Fifty-Fourth World Health Assembly, resolution WHA54.19, of providing treatment for schistosomiasis and soil-transmitted helminthiases (STH to 75% of school-aged children at risk, which requires attending at least 166,000 residents in the 7-14 age range by year 2010 in that important endemic area. In the present study, secondary demographic and parasitological data from a representative municipality of the ZMP are analyzed to provide evidence that the current, community-based approach to control schistosomiasis and STH is unlikely to attain the WHA-54.19 minimum goal and to suggest that school-based control actions are also needed. METHODOLOGY/PRINCIPAL FINDINGS: Data available on the PCE-SUS activities related to diagnosis and treatment of the population from the study municipality were obtained from the State Secretary of Health of Pernambuco (SES/PE for 2002-2006, complemented by the Municipal Secretary of Health (SMS for 2003-2004. Data from a school-based stool survey carried out by the Schistosomiasis Reference Service of the Oswaldo Cruz Foundation (SRE/Fiocruz in 2004 were used to provide information on infection status variation among school-aged children (7-14 years. According to the SES, from 2004 to 2006, only 2,977 (19.5% of the estimated 15,288 residents of all ages were examined, of which 396 (13.3% were positive for Schistosoma mansoni. Among these, only 180 (45.5% were treated. According to the SMS, of the 1,766 examined in the 2003-2004 population stool survey 570 (32.3% were children aged 7-14 years. One year later, the SRE/Fiocruz school survey revealed that the infection status among those children remained unchanged
Full Text Available INTRODUCTION: Schistosomiasis (bilharzia, one of the most relevant parasitoses of humans, is confirmed by microscopic detection of eggs in stool, urine, or organ biopsies. The sensitivity of these procedures is variable due to fluctuation of egg shedding. Serological tests on the other hand do not distinguish between active and past disease. In patients with acute disease (Katayama syndrome, both serology and direct detection may produce false negative results. To overcome these obstacles, we developed a novel diagnostic strategy, following the rationale that Schistosoma DNA may be liberated as a result of parasite turnover and reach the blood. Cell-free parasite DNA (CFPD was detected in plasma by PCR. METHODOLOGY/PRINCIPAL FINDINGS: Real-time PCR with internal control was developed and optimized for detection of CFPD in human plasma. Distribution was studied in a mouse model for Schistosoma replication and elimination, as well as in human patients seen before and after treatment. CFPD was detectable in mouse plasma, and its concentration correlated with the course of anti-Schistosoma treatment. Humans with chronic disease and eggs in stool or urine (n = 14 showed a 100% rate of CFPD detection. CFPD was also detected in all (n = 8 patients with Katayama syndrome. Patients in whom no viable eggs could be detected and who had been treated for schistomiasis in the past (n = 30 showed lower detection rates (33.3% and significantly lower CFPD concentrations. The duration from treatment to total elimination of CFPD from plasma was projected to exceed one year. CONCLUSIONS/SIGNIFICANCE: PCR for detection of CFPD in human plasma may provide a new laboratory tool for diagnosing schistosomiasis in all phases of clinical disease, including the capacity to rule out Katayama syndrome and active disease. Further studies are needed to confirm the clinical usefulness of CFPD quantification in therapy monitoring.
Kedma de Magalhães Lima
Full Text Available INTRODUCTION : Bacterial translocation is the invasion of indigenous intestinal bacteria through the gut mucosa to normally sterile tissues and internal organs. Schistosomiasis may cause alterations in the immune system and damage to the intestines, portal system and mesenteric lymph nodes. This study investigated bacterial translocation and alterations in the intestinal microbiota and mucosa in schistosomiasis and splenectomized mice. METHODS : Forty female 35-day-old Swiss Webster mice were divided into the following four groups with 10 animals each: schistosomotic (ESF, splenectomized schistosomotic (ESEF, splenectomized (EF and control (CF. Infection was achieved by introduction of 50 Schistosoma mansoni (SLM cercariae through the skin. At 125 days after birth, half of the parasitized and unparasitized mice were subjected to splenectomy. Body weights were recorded for one week after splenectomy; then, the mice were euthanized to study bacterial translocation, microbiota composition and intestinal morphometry. RESULTS : We observed significant reductions in the weight increases in the EF, ESF and ESEF groups. There were increases of at least 1,000 CFU of intestinal microbiota bacteria in these groups compared with the CF. The EF, ESF and ESEF mice showed decreases in the heights and areas of villi and the total villus areas (perimeter. We observed frequent co-infections with various bacterial genera. CONCLUSIONS : The ESEF mice showed a higher degree of sepsis. This finding may be associated with a reduction in the immune response associated with the absence of the spleen and a reduction in nutritional absorption strengthened by both of these factors (Schistosoma infection and splenectomy.
Mark S Pearson
Full Text Available The large extracellular loop of the Schistosoma mansoni tetraspanin, Sm-TSP-2, when fused to a thioredoxin partner and formulated with Freund's adjuvants, has been shown to be an efficacious vaccine against murine schistosomiasis. Moreover, Sm-TSP-2 is uniquely recognised by IgG(1 and IgG(3 from putatively resistant individuals resident in S. mansoni endemic areas in Brazil. In the present study, we expressed Sm-TSP-2 at high yield and in soluble form in E. coli without the need for a solubility enhancing fusion partner. We also expressed in E. coli a chimera called Sm-TSP-2/5B, which consisted of Sm-TSP-2 fused to the immunogenic 5B region of the hookworm aspartic protease and vaccine antigen, Na-APR-1. Sm-TSP-2 formulated with alum/CpG showed significant reductions in adult worm and liver egg burdens in two separate murine schistosomiasis challenge studies. Sm-TSP-2/5B afforded significantly greater protection than Sm-TSP-2 alone when both antigens were formulated with alum/CpG. The enhanced protection obtained with the chimeric fusion protein was associated with increased production of anti-Sm-TSP-2 antibodies and IL-4, IL-10 and IFN-γ from spleen cells of vaccinated animals. Sera from 666 individuals from Brazil who were infected with S. mansoni were screened for potentially deleterious IgE responses to Sm-TSP-2. Anti-Sm-TSP-2 IgE to this protein was not detected (also shown previously for Na-APR-1, suggesting that the chimeric antigen Sm-TSP-2/5B could be used to safely and effectively vaccinate people in areas where schistosomes and hookworms are endemic.
Bezerra, A.S.; D' Ippolito, G.; Caldana, R.P.; Cecin, A.O.; Ahmed, M.; Szejnfeld, J. [Dept. of Diagnostic Imaging, Federal Univ. of Sao Paulo, Sao Paulo (Brazil)
Purpose: To evaluate the hepatosplenic manifestations and the portal venous system in patients with chronic infection by Schistosoma mansoni. Material and Methods: A cross-sectional observational study was performed in 28 patients with chronic hepatosplenic schistosomiasis submitted to magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA) of the abdomen. Images were interpreted independently by two radiologists to determine the reproducibility of image interpretation and who evaluated the presence of morphological alterations in the liver and spleen, such as hepatosplenomegaly, hepatic fissure widening, periportal fibrosis, and the presence of siderotic nodules. Interobserver and intra-observer agreement were measured with the kappa and intraclass correlation tests. Evaluation of venous collateral pathways and portal and splenic veins was done in consensus by both examiners. Results: Observers identified enlargement of the left lobe (78.5-92.8%) and caudate-to-right-lobe ratio (78.5-92.8%), irregularity of hepatic contours (89.2-96.4%), fissure widening (89.2-100%), and splenic siderotic nodules (84.2%). Splenomegaly, heterogeneity of hepatic parenchyma, peripheral hepatic vessels, and periportal fibrosis were observed in 100% of patients. MRI findings presented almost perfect interobserver (kappa 0.65-1) and intra-observer (kappa = 0.73-1 for observer 1, and kappa = 0.65-1 for observer 2) agreement for the variables analyzed. MRA showed the presence of collateral pathways in the majority of patients (71.4%) along with widening of portal and splenic veins. Conclusion: Using MRI, hepatosplenic alterations in schistosomiasis are characterized by heterogeneity of hepatic parenchyma, presence of peripheral perihepatic vessels, periportal fibrosis, splenomegaly, siderotic nodules, and the presence of venous collateral pathways.
Braga, Bruno Perocco; Costa Junior, Leodante Batista da [Hospital da Baleia, Belo Horizonte, MG (BRazil). Servico de Neurocirurgia; Lambertucci, Jose Roberto [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Faculdade de Medicina. Servico de Doencas Infecciosas e Parasitarias
A 15-year-old boy was admitted to hospital with a history of headache, dizziness, vomiting and double vision that started two weeks before. His parents denied any previous disease. During clinical examination he presented diplopia on lateral gaze to the left and horizontal nystagmus. No major neurological dysfunction was detected. He was well built, mentally responsive and perceptive. Laboratory findings revealed a leukocyte count of 10,000/mL, a normal red blood cell count and no eosinophilia. The magnetic resonance images (MRI) of the brain showed a left cerebellar lesion with mass effect compressing the surrounding tissues. Contrast-enhanced images showed a mass like structure and punctate nodules (Figures A and B: axial and coronal contrast-enhanced T1-weighted MR images showed the nodular - yellow arrows - enhancement pattern of a left cerebellar intraxial lesion). The lesion extended to the vermis and brachium pons and compressed the medulla. There was no hydrocephalus. He was taken to the operating room with the presumptive diagnosis of a neuroglial tumor, and submitted to a lateral suboccipital craniectomy. A brown, brittle tumoral mass without a clearly defined margin with the cerebellar tissue was removed. Microscopic examination revealed schistosomal granulomas in the productive phase in the cerebellum (Figure C). After surgery, treatment with praziquantel (50 mg/kg/dia, single dose) and prednisone (1 mg/kg/day) was offered and the patient improved quickly. Thirty days later he was seen again at the outpatient clinic: he was asymptomatic and with no neurological impairment. This is the eighth case of cerebellar involvement in schistosomiasis mansoni and the second report of a tumoral form of cerebellar schistosomiasis documented by magnetic resonance images. (author)
Webbe, G; el Hak, S
Continuing epidemiological evaluation of schistosomiasis intervention measures applied in Middle and Upper Egypt since 1985 indicate that a large measure of control of Schistosoma haematobium has been achieved in relation to both prevalence and intensity of the infection and incidence of new infections. Transmission control has, however, been inadequate in many areas, since numerous re-infections occurred in treated schoolchildren. Variable compliance rates in the chemotherapy delivery system were probably, in part, an important contributory factor, and short-comings of the selective and/or focal mollusciciding strategy were also probably responsible for many new cases and re-infections. Chemotherapy delivery has now been improved following the introduction of single dose treatments with praziquantel and it is expected that there will be an increased demand for treatment following the introduction of a new information-education-communication campaign. In communities with geometric mean egg-output of less than 50 per 10 ml of urine, acceptable control of the potential for development of schistosomal disease can be expected. It is concluded, therefore, that the future maintenance control strategy in this project area may call for more frequent chemotherapy treatments in identified foci of high prevalence and intensity, with complementary focal mollusciciding and/or targeted treatment of schoolchildren, in order to prevent the serious consequences of infection. In 1988 the annual cost of schistosomiasis control measures per person throughout the project area (2 million irrigated feddans (c .800,000 hectares] containing 12 million people) was 0.5 Egyptian pounds (LE) (US$ 0.20), representing 5.2% of the annual expenditure per person in Egypt (LE 9.6) for all health services.
Full Text Available Although a disease of great antiquity, scientific studies of schistosomiasis began only 150 years ago. The complete life-cycle was not described until just before the First World War, making it possible at last to plan proper community control programmes. Inadequate tools prevented their effective implementation until well after the Second World War when new tools became available, thanks to the newly formed World Health Organization. Molluscicides spearheaded control programmes until the late 1970s but were then replaced by the newly developed, safe drugs still used today. Whatever the method used, the initial goal of eradication was, in the light of experience and cost, gradually replaced by less ambitious targets; first to stop transmission and then to reduce morbidity. The most successful programmes combined several methods to minimise reinfection after chemotherapy. Comparisons between different programmes are difficult without using appropriate, standardised diagnostic techniques and the correct epidemiological measurements. Some examples will be presented, mainly from our studies on Schistosoma mansoni in Kenya. Drug resistance on a scale comparable with malaria has not occurred in schistosomiasis but the likely withdrawal of all drugs except praziquantel leaves its control extremely vulnerable to this potential problem. An effective, affordable vaccine for use in endemic countries is unlikely to be ready for at least 5 years, and developing strategies for its use could take a further decade or more, judging from experience with drugs and molluscicides. In the interim, by analogy with malaria, the most cost-effective approach would the use of drugs combined with other methods to stop transmission, including molluscicides. The cost of molluscicides needs to be reduced and fears allayed about their supposedly adverse ecological effects.
Jack E T Grimes
Full Text Available Access to "safe" water and "adequate" sanitation are emphasized as important measures for schistosomiasis control. Indeed, the schistosomes' lifecycles suggest that their transmission may be reduced through safe water and adequate sanitation. However, the evidence has not previously been compiled in a systematic review.We carried out a systematic review and meta-analysis of studies reporting schistosome infection rates in people who do or do not have access to safe water and adequate sanitation. PubMed, Web of Science, Embase, and the Cochrane Library were searched from inception to 31 December 2013, without restrictions on year of publication or language. Studies' titles and abstracts were screened by two independent assessors. Papers deemed of interest were read in full and appropriate studies included in the meta-analysis. Publication bias was assessed through the visual inspection of funnel plots and through Egger's test. Heterogeneity of datasets within the meta-analysis was quantified using Higgins' I2.Safe water supplies were associated with significantly lower odds of schistosomiasis (odds ratio (OR = 0.53, 95% confidence interval (CI: 0.47-0.61. Adequate sanitation was associated with lower odds of Schistosoma mansoni, (OR = 0.59, 95% CI: 0.47-0.73 and Schistosoma haematobium (OR = 0.69, 95% CI: 0.57-0.84. Included studies were mainly cross-sectional and quality was largely poor.Our systematic review and meta-analysis suggests that increasing access to safe water and adequate sanitation are important measures to reduce the odds of schistosome infection. However, most of the studies were observational and quality was poor. Hence, there is a pressing need for adequately powered cluster randomized trials comparing schistosome infection risk with access to safe water and adequate sanitation, more studies which rigorously define water and sanitation, and new research on the relationships between water, sanitation, hygiene, human
Full Text Available Oncomelania hupensis is the sole intermediate host snail of Schistosoma japonicum in China. Snail control by molluscicide remains one of the most effective measures of schistosomiasis japonica control. A 50% wettable powder of niclosamide ethanolamine salt (WPN is widely used for snail control in China. However, WPN is costly and toxic to fish. A novel molluscicide named LDS, the salt of quinoid-2′, 5-dichloro-4′-nitrosalicylanilide from niclosamide, has been developed. To evaluate the effects of large-scale field application of LDS on field snail control, tests were conducted in 15 counties of Hubei Province, China. Active adult snails, were immersed in 0.2, 0.4, and 0.6 g/m3 of 10% LDS, 1.0 g/m3 of 50% WPN was used as the molluscicide control, and then the mortality rates of snails were investigated after 1, 2, and 3 days. In addition, four active concentrations of 10% LDS (0.4, 0.6, 0.8 and 1.0 g/m2 were applied by spraying and powdering in the field. 1.0 g/m2 of 50% WPN was used as the molluscicide control, and then the mortality rates of snails were observed after 1, 3, and 7 days. The results indicated that 0.4 g/m3 LDS applied by the immersion or 0.6 g/m2 LDS applied by spraying and powdering achieved the same molluscicidal effect as that of WPN, regardless of exposure time. By using different methods, the snail mortality rates in the molluscicide groups were related to exposure time and concentration, respectively. LDS costs less than WPN; thus, LDS is suitable and applicable for use as a molluscicide in schistosomiasis japonica epidemic areas.
Grimes, Jack E T; Croll, David; Harrison, Wendy E; Utzinger, Jürg; Freeman, Matthew C; Templeton, Michael R
Access to "safe" water and "adequate" sanitation are emphasized as important measures for schistosomiasis control. Indeed, the schistosomes' lifecycles suggest that their transmission may be reduced through safe water and adequate sanitation. However, the evidence has not previously been compiled in a systematic review. We carried out a systematic review and meta-analysis of studies reporting schistosome infection rates in people who do or do not have access to safe water and adequate sanitation. PubMed, Web of Science, Embase, and the Cochrane Library were searched from inception to 31 December 2013, without restrictions on year of publication or language. Studies' titles and abstracts were screened by two independent assessors. Papers deemed of interest were read in full and appropriate studies included in the meta-analysis. Publication bias was assessed through the visual inspection of funnel plots and through Egger's test. Heterogeneity of datasets within the meta-analysis was quantified using Higgins' I2. Safe water supplies were associated with significantly lower odds of schistosomiasis (odds ratio (OR) = 0.53, 95% confidence interval (CI): 0.47-0.61). Adequate sanitation was associated with lower odds of Schistosoma mansoni, (OR = 0.59, 95% CI: 0.47-0.73) and Schistosoma haematobium (OR = 0.69, 95% CI: 0.57-0.84). Included studies were mainly cross-sectional and quality was largely poor. Our systematic review and meta-analysis suggests that increasing access to safe water and adequate sanitation are important measures to reduce the odds of schistosome infection. However, most of the studies were observational and quality was poor. Hence, there is a pressing need for adequately powered cluster randomized trials comparing schistosome infection risk with access to safe water and adequate sanitation, more studies which rigorously define water and sanitation, and new research on the relationships between water, sanitation, hygiene, human behavior
Leonardo, Lydia R; Rivera, Pilarita; Saniel, Ofelia; Villacorte, Elena; Crisostomo, Bobby; Hernandez, Leda; Baquilod, Mario; Erce, Edgardo; Martinez, Ruth; Velayudhan, Raman
The first two phases of a national prevalence survey of schistosomiasis in The Philippines were completed in Mindanao in 2005 and the Visayas in the first quarter of 2007. The design was a stratified two-step systematic cluster sampling, with two Kato-Katz thick smears examined from each participant. In Mindanao, a total of 22 provinces spread in six regions were covered by the survey with five barangays (equivalent to a village) per province for a total of 110 barangays. The response rate was 70.9% with a total of 21,390 individuals examined. The province of Maguindanao, a known endemic area for schistosomiasis japonica, failed to take part in the survey. In the Visayas, 10 out of 11 provinces, spread out in three regions, participated in the survey. There were 6321 respondents for an overall participation rate of 32.2%. Mindanao showed a wider coverage of the disease than the Visayas (60% versus 45%). By region, Caraga or Region 13 ranked first in Mindanao and Region 8 in the Visayas. By province, Agusan del Sur is first on the list, followed by Northern Samar and then Eastern Samar. Overall, the prevalence rate among males is higher than that of females suggesting the occupational hazard of farming and fishing among the males. The higher exposure among farmers and fishermen is also borne out by the age distribution of the disease. Prevalence remains consistently high among the adults compared with the younger age groups. The survey also covered other helminth infections that can be detected in a stool survey, notably soil-transmitted helminthes and food-borne trematodes.
Siqueira, Liliane Maria Vidal; Couto, Flavia Fernanda Bubula; Taboada, Diana; Oliveira, Áureo Almeida de; Carneiro, Nidia Francisca de Figueiredo; Oliveira, Edward; Coelho, Paulo Marcos Zech; Katz, Naftale
Schistosomiasis, caused by Schistosoma mansoni, is a public health concern in Brazil. However, the most popular diagnostic method, the Kato-Katz technique, exhibits low sensitivity in low-endemicity areas. We aimed to compare the performance of an immunological assay, the point-of-care circulating cathodic antigen (POC-CCA®) test, with that of two parasitological techniques in a low-endemicity population. Our study included 141 individuals living in Estreito de Miralta, Minas Gerais, Brazil. Fecal samples were obtained from all participants and analyzed for schistosomiasis using two parasitological techniques: the Kato-Katz technique and the saline gradient technique. Additionally, POC-CCA® strips were utilized for testing urine samples. The results obtained by the different techniques were compared. Analysis of two or 24 slides using the Kato-Katz technique resulted in a positivity rate of 10.6% (15/141) or 19.1% (27/141), respectively. The saline gradient technique yielded a positivity rate of 17.0% (24/141). The prevalence according to both parasitological techniques was 24.1% (34/141). The POC-CCA® test yielded a positivity rate of 22.7% (32/141); however, the positivity rate was merely 2.1% if trace results were considered negative. The agreements observed between POC-CCA® and the parasitological techniques were good (Kappa indexes > 0.64). The POC-CCA® test was more sensitive than the two-slide Kato-Katz technique (p < 0.05) in detecting cases of S. mansoni infection when trace results were considered positive. These findings reinforce the importance of using multiple diagnostic techniques in low-endemicity areas for effective control of disease.
Larkin, Bridget M; Smith, Patrick M; Ponichtera, Holly E; Shainheit, Mara G; Rutitzky, Laura I; Stadecker, Miguel J
Schistosomiasis is a major tropical disease caused by trematode helminths in which the host mounts a pathogenic immune response against tissue-trapped parasite eggs. The immunopathology consists of egg antigen-specific CD4 T cell-mediated granulomatous inflammation that varies greatly in magnitude in humans and among mouse strains in an experimental model. New evidence, covered in this review, intimately ties the development of severe pathology to IL-17-producing CD4 T helper (Th17) cells, a finding that adds a new dimension to the traditional CD4 Th1 vs. Th2 cell paradigm. Most examined mouse strains, in fact, develop severe immunopathology with substantial Th17 as well as Th1 and Th2 cell responses; a solely Th2-polarized response is an exception that is only observed in low-pathology strains such as the C57BL/6. The ability to mount pathogenic Th17 cell responses is genetically determined and depends on the production of IL-23 and IL-1β by antigen presenting cells following recognition of egg antigens; analyses of several F2 progenies of (high × low)-pathology strain crosses demonstrated that quantitative trait loci governing IL-17 levels and disease severity vary substantially from cross to cross. Low pathology is dominant, which may explain the low incidence of severe disease in humans; however, coinfection with intestinal nematodes can also dampen pathogenic Th17 cell responses by promoting regulatory mechanisms such as those afforded by alternatively activated macrophages and T regulatory cells. A better understanding of the pathways conducive to severe forms of schistosomiasis and their regulation should lead to interventions similar to those presently used to manage other immune-mediated diseases.
Pearson, Mark S; Pickering, Darren A; McSorley, Henry J; Bethony, Jeffrey M; Tribolet, Leon; Dougall, Annette M; Hotez, Peter J; Loukas, Alex
The large extracellular loop of the Schistosoma mansoni tetraspanin, Sm-TSP-2, when fused to a thioredoxin partner and formulated with Freund's adjuvants, has been shown to be an efficacious vaccine against murine schistosomiasis. Moreover, Sm-TSP-2 is uniquely recognised by IgG(1) and IgG(3) from putatively resistant individuals resident in S. mansoni endemic areas in Brazil. In the present study, we expressed Sm-TSP-2 at high yield and in soluble form in E. coli without the need for a solubility enhancing fusion partner. We also expressed in E. coli a chimera called Sm-TSP-2/5B, which consisted of Sm-TSP-2 fused to the immunogenic 5B region of the hookworm aspartic protease and vaccine antigen, Na-APR-1. Sm-TSP-2 formulated with alum/CpG showed significant reductions in adult worm and liver egg burdens in two separate murine schistosomiasis challenge studies. Sm-TSP-2/5B afforded significantly greater protection than Sm-TSP-2 alone when both antigens were formulated with alum/CpG. The enhanced protection obtained with the chimeric fusion protein was associated with increased production of anti-Sm-TSP-2 antibodies and IL-4, IL-10 and IFN-γ from spleen cells of vaccinated animals. Sera from 666 individuals from Brazil who were infected with S. mansoni were screened for potentially deleterious IgE responses to Sm-TSP-2. Anti-Sm-TSP-2 IgE to this protein was not detected (also shown previously for Na-APR-1), suggesting that the chimeric antigen Sm-TSP-2/5B could be used to safely and effectively vaccinate people in areas where schistosomes and hookworms are endemic.
Full Text Available The effects of schistosomiasis on microsomal enzymes were studied on post-infection day 90 when accumulated damage and fibrosis are most intense but granulomatous reaction around the eggs harbored in the liver is smaller than during the earlier phases. Swiss Webster (SW and DBA/2 mice of either sex (N = 12 per sex per group were infected with 100 Schistosoma mansoni cercariae on postnatal day 10 and killed on post-infection day 90. Cytochrome P-450 (CYP concentration and alkoxyresorufin-O-dealkylases (EROD, MROD, BROD, and PROD, p-nitrophenol-hydroxylase (PNPH, coumarin-7-hydroxylase (COH, and UDP-glucuronosyltransferase (UGT activities were measured in hepatic microsomes. Age-matched mice of the same sex and strain were used as controls. In S. mansoni-infected mice, CYP1A- and 2B-mediated activities (control = 100% were reduced in SW (EROD: male (M 36%, female (F 38%; MROD: M 38%, F 39%; BROD: M 46%, F 19%; PROD: M 50%, F 28% and DBA/2 mice (EROD: M 64%, F 58%; MROD: M 60%; BROD: F 49%; PROD: M 73% while PNPH (CYP2E1 was decreased in SW (M 31%, F 38% but not in DBA/2 mice. COH did not differ between infected and control DBA/2 and UGT, a phase-2 enzyme, was not altered by infection. In conclusion, chronic S. mansoni infection reduced total CYP content and all CYP-mediated activities evaluated in SW mice, including those catalyzed by CYP2E1 (PNPH, CYP1A (EROD, MROD and 2B (BROD, PROD. In DBA/2 mice, however, CYP2A5- and 2E1-mediated activities remained unchanged while total CYP content and activities mediated by other CYP isoforms were depressed during chronic schistosomiasis.
Lu, Yan; Xu, Bin; Ju, Chuan; Mo, Xiaojin; Chen, Shenbo; Feng, Zheng; Wang, Xiaoning; Hu, Wei
Schistosomiasis is a chronic disease caused by trematode flatworms of the genus Schistosoma. The disease remains a serious public health problem in endemic countries and affects at least 207 million people worldwide. A definite diagnosis of the disease plays a key role in the control of schistosomiasis. The detection of schistosome circulating antigens (CAs) is an effective approach to discriminate between previous exposure and current infection. Different methods have been investigated for detecting the CAs. However, the components of the schistosome CAs remain unclear. In this study, we analyzed the CAs in sera of patients infected with Schistosoma japonicum. The parasites were collected from the infected rabbits for preparing the adult worm antigen (AWA). The hyline hens were immunized subcutaneously with AWA to produce anti-AWA IgY. The IgY was purified by water-dilution and ammonium sulfate precipitation method and identified by ELISA and Western blotting. After purification and characterization, IgY was immobilized onto the resin as a capture antibody. The circulating antigens were immune-precipitated from patients' serum samples by direct immunoprecipitation. The precipitated proteins were separated by one-dimensional electrophoresis and analyzed by LC-MS/MS. Firstly, the IgY against AWA was produced from the eggs of immunized hens by AWA, which gave a titer of 1:12800. The purified IgY was used as the capture antibody to enrich the CAs in sera of S. japonicum infected patients through immunoprecipitation. The CAs were determined by LC-MS/MS. There were four proteins, including protein BUD31 homolog, ribonuclease, SJCHGC06971 protein and SJCHGC04754 protein, which were identified among the CAs. We developed a novel method based on IgY for identification and profiling CAs in sera of S. japonicum infected patients. Four new CAs were identified and have potential value for further development of an antigen assay.
Full Text Available Abstract Background Schistosomiasis is a chronic disease caused by trematode flatworms of the genus Schistosoma. The disease remains a serious public health problem in endemic countries and affects at least 207 million people worldwide. A definite diagnosis of the disease plays a key role in the control of schistosomiasis. The detection of schistosome circulating antigens (CAs is an effective approach to discriminate between previous exposure and current infection. Different methods have been investigated for detecting the CAs. However, the components of the schistosome CAs remain unclear. In this study, we analyzed the CAs in sera of patients infected with Schistosoma japonicum. Methods The parasites were collected from the infected rabbits for preparing the adult worm antigen (AWA. The hyline hens were immunized subcutaneously with AWA to produce anti-AWA IgY. The IgY was purified by water-dilution and ammonium sulfate precipitation method and identified by ELISA and Western blotting. After purification and characterization, IgY was immobilized onto the resin as a capture antibody. The circulating antigens were immune-precipitated from patients′ serum samples by direct immunoprecipitation. The precipitated proteins were separated by one-dimensional electrophoresis and analyzed by LC-MS/MS. Results Firstly, the IgY against AWA was produced from the eggs of immunized hens by AWA, which gave a titer of 1:12800. The purified IgY was used as the capture antibody to enrich the CAs in sera of S. japonicum infected patients through immunoprecipitation. The CAs were determined by LC-MS/MS. There were four proteins, including protein BUD31 homolog, ribonuclease, SJCHGC06971 protein and SJCHGC04754 protein, which were identified among the CAs. Conclusions We developed a novel method based on IgY for identification and profiling CAs in sera of S. japonicum infected patients. Four new CAs were identified and have potential value for further development
Daniel Santos Oliveira
Full Text Available Introduction Our objective was to evaluate the influence of rainfall regime on the population dynamics of Biomphalaria in a potential urban focus of schistosomiasis in Aracaju, Brazil, during 2009-2010. Methods Snails were collected monthly and were counted, measured and identified; the level of infection and fecal contamination at the sampling sites was determined; rainfall data were obtained. Results High levels of fecal contamination were observed, and the abundance of Biomphalaria glabrata increased during the rainy and post-rainy seasons. The snails' size was variable, and infected snails were identified independently of rainfall. Conclusions These results provide evidence of anthropogenic and climate interference in an urban focus of schistosomiasis in the Aracaju metropolitan area.
Full Text Available Abstract Background Schistosomiasis remains a major public health problem in Kenya. Inadequate knowledge, attitudes and practices (KAP on causative factors are some of the critical factors for the increased prevalence. The study assessed KAP on the control and prevention of schistosomiasis infection in Mwea division, Kirinyaga County-Kenya. Four hundred and sixty five house-hold heads were enrolled in this study by use of simple random sampling technique. Methods The study employed an analytical descriptive cross sectional design utilizing both quantitative and qualitative data collection methods. A pretested structured questionnaire, Focus Group Discusions (FGDs and Key Informant Interviews (KII guides were used for data collection. Descriptive statistics and Chi square tests and Fisher’s exact tests were computed where applicable. Data from the FGDs and KIIs were analyzed using NUID.IST NUIRO.6 software. Results Significant associations between knowledge and demographic factors i.e. age (p = 0.011, education level (p = 0.046, were reported. Handwashing after visiting the toilet (p = 0.001, having a toilet facility at home (p = 0.014; raring animals at home (p = 0.031, households being affected by floods (p = 0.005 and frequency of visits to the paddies (p = 0.037 had a significant association with respondents practices and schistosomiasis infection. Further significance was reported on households being affected by floods during the rainy season (p < 0.001, sources of water in a household (p < 0.047 and having a temporary water body in the area (p = 0.024 with increase in schistosomiasis infection. Results revealed that respondents practices were not significantly associated with gender (p = 0.060, marital status (p = 0.71, wearing of protective gear (p = 0.142 and working on the paddies (p = 0.144. Conclusions This study reveals that knowledge about the cause, transmission, symptoms and
Paula Carolina Valença Silva
Full Text Available INTRODUCTION : We hypothesized higher mannose-binding lectin level and classic factors (i.e., age, sex, alcohol consumption, exposure, and specific treatment are associated with the severity of periportal fibrosis in schistosomiasis. METHODS : This cross-sectional study involved 79 patients infected with Schistosoma mansoni with severe or mild/moderate periportal fibrosis. Serum concentrations of mannose-binding lectin were obtained by enzyme-linked immunosorbent assay (ELISA. RESULTS: Higher serum level of mannose-binding lectin was significantly associated with advanced periportal fibrosis. CONCLUSIONS: Mannose-binding lectin may contribute to liver pathology in schistosomiasis and may represent a risk factor for advanced periportal fibrosis in the Brazilian population studied.
Suellen D’arc Santos Oliveira
Full Text Available Schistosomiasis is a chronic inflammatory disease whose macrophages are involved in immunopathology modulation. Although P2X7 receptor signaling plays an important role in inflammatory responses mediated by macrophages, no reports have examined the role of P2X7 receptors in macrophage function during schistosomiasis. Thus, we evaluated P2X7 receptor function in peritoneal macrophages during schistosomiasis using an ATP-induced permeabilization assay and measurements of the intracellular Ca2+ concentration. ATP treatment induced significantly less permeabilization in macrophages from S. mansoni-infected mice than in control cells from uninfected animals. Furthermore, P2X7-mediated increases in intracellular Ca2+ levels were also reduced in macrophages from infected mice. TGF-β1 levels were increased in the peritoneal cavity of infected animals, and pretreatment of control macrophages with TGF-β1 reduced ATP-induced permeabilization, mimicking the effect of S. mansoni infection. Western blot and qRT-PCR data showed no difference in P2X7 protein and mRNA between uninfected, infected, and TGF-β1-treated groups. However, immunofluorescence analysis revealed reduced cell surface localization of P2X7 receptors in macrophages from infected and TGF-β1-treated mice compared to controls. Therefore, our data suggest that schistosomiasis reduces peritoneal macrophage P2X7 receptor signaling. This effect is likely due to the fact that infected mice have increased levels of TGF-β1, which reduces P2X7 receptor cell surface expression.
Pedersen, Ulrik Bo; Karagiannis-Voules, Dimitrios-Alexios; Midzi, Nicholas
Temperature, precipitation and humidity are known to be important factors for the development of schistosome parasites as well as their intermediate snail hosts. Climate therefore plays an important role in determining the geographical distribution of schistosomiasis and it is expected that clima...... for Zimbabwe from 1981 and the period preceding a survey and control campaign in 2010 parallels a shift towards a drier and warmer climate. However, a statistically significant relationship between climate change and the change in prevalence could not be established....
Suellen D S Oliveira
Full Text Available BACKGROUND AND AIMS: Schistosomiasis is an intravascular parasitic disease associated with inflammation. Endothelial cells control leukocyte transmigration and vascular permeability being modulated by pro-inflammatory mediators. Recent data have shown that endothelial cells primed in vivo in the course of a disease keep the information in culture. Herein, we evaluated the impact of schistosomiasis on endothelial cell-regulated events in vivo and in vitro. METHODOLOGY AND PRINCIPAL FINDINGS: The experimental groups consisted of Schistosoma mansoni-infected and age-matched control mice. In vivo infection caused a marked influx of leukocytes and an increased protein leakage in the peritoneal cavity, characterizing an inflamed vascular and cellular profile. In vitro leukocyte-mesenteric endothelial cell adhesion was higher in cultured cells from infected mice as compared to controls, either in the basal condition or after treatment with the pro-inflammatory cytokine tumor necrosis factor (TNF. Nitric oxide (NO donation reduced leukocyte adhesion to endothelial cells from control and infected groups; however, in the later group the effect was more pronounced, probably due to a reduced NO production. Inhibition of control endothelial NO synthase (eNOS increased leukocyte adhesion to a level similar to the one observed in the infected group. Besides, the adhesion of control leukocytes to endothelial cells from infected animals is similar to the result of infected animals, confirming that schistosomiasis alters endothelial cells function. Furthermore, NO production as well as the expression of eNOS were reduced in cultured endothelial cells from infected animals. On the other hand, the expression of its repressor protein, namely caveolin-1, was similar in both control and infected groups. CONCLUSION/SIGNIFICANCE: Schistosomiasis increases vascular permeability and endothelial cell-leukocyte interaction in vivo and in vitro. These effects are partially
Ana Lúcia P Hanemann
Full Text Available The aim of this study is to investigate renal markers and the biomarker MCP-1 in patients with schistosomiasis mansoni. This is a cross-sectional study with 85 patients aged 5 to 48 years, with a confirmed diagnosis of schistosomiasis mansoni through the Kato-Katz method. The patients were divided in three groups: control (G-I; infected by S. mansoni before treatment (G-II and infected by S. mansoni after treatment (G-III. Renal function was evaluated by tubular and glomerular biomarkers and through urinary MCP-1. Patients' mean age was 23.2 ± 13 years. There was no statistically significant difference between the groups regarding tubular and glomerular function evaluated through the traditional biomarkers. MCP-1 was higher in G-II and G-III, when compared to G-I; p=0.009 and p=0.007, respectively. There was no difference when comparing groups G-II and G-III (p=0.892. Although it was not different among the groups, there was a significant correlation between albuminuria and MCP-1. There was a significant increase in urinary MCP-1 levels in patients with schistosomiasis mansoni, which was associated with albuminuria. This protein has a role in the recruitment of monocytes to injury and inflammation sites . The increase of MCP-1 in the urine evidences that there is silent renal inflammation in these patients and the inflammatory status is not interrupted by specific treatment of the offending agent. Our findings suggest that urinary MCP-1 can be a sensitive marker of renal injury in patients with schistosomiasis mansoni.
Darren J Gray
Full Text Available Schistosoma japonicum is a major public health concern in the Peoples' Republic of China (PRC, with about 800,000 people infected and another 50 million living in areas at risk of infection. Based on ecological, environmental, population genetic and molecular factors, schistosomiasis transmission in PRC can be categorised into four discrete ecosystems or transmission modes. It is predicted that, long-term, the Three Gorges Dam (TGD will impact upon the transmission of schistosomiasis in the PRC, with varying degree across the four transmission modes.We undertook longitudinal surveillance from 2002 to 2006 in sentinel villages of the three transmission modes below the TGD across four provinces (Hunan, Jiangxi, Hubei and Anhui to determine whether there was any immediate impact of the TGD on schistosomiasis transmission. Eight sentinel villages were selected to represent both province and transmission mode. The primary end point measured was human incidence. Here we present the results of this five-year longitudinal cohort study. Results showed that the incidence of human S. japonicum infection declined considerably within individual villages and overall mode over the course of the study. This is also reflected in the yearly odds ratios (adjusted for infection risk that showed significant (P<0.01 downward trends in all modes over the follow-up period.The decrease in human S. japonicum incidence observed across all transmission modes in this study can probably be attributed to the annual human and bovine PZQ chemotherapy. If an increase in schistosome transmission had occurred as a result of the TGD, it would be of negligible size compared to the treatment induced decline seen here. It appears therefore that there has been virtually no immediate impact of the TGD on schistosomiasis transmission downstream of the dam.
Full Text Available BACKGROUND: In Uganda, the current national health sector strategic and investment plan underscores schistosomiasis as one of the diseases targeted for elimination by the year 2015. However, uptake of treatment among school children is unknown but suspected to be low. We estimated the uptake and predictors of preventive treatment with praziquantel. METHODS: In a cross sectional study carried out in Jinja district of Uganda, a random sample of 1,010 children in 12 primary schools was questioned about their uptake of praziquantel, knowledge and perceptions about schistosomiasis, support for taking preventive treatment and the dangers of taking praziquantel. The prevalence and mean intensity of infection with Schistosoma mansoni were determined. RESULTS: Self reported uptake of praziquantel at last mass treatment was 28.2% (95% confidence interval (CI: 22.9%-33.6%. Overall prevalence and mean intensity of S. mansoni infection was 35% (95% CI: 25.4%-37.9% and 116.1 eggs per gram (epg of stool (95% CI: 98.3-137.1 respectively. Uptake of praziquantel was more likely if a child was from a school with high prevalence of infection, had knowledge about schistosomiasis transmission and prevention, and reported teachers' support to take praziquantel. Of the 285 children who took praziquantel, 142 (49.8% developed side effects. Of the 725 children who did not take the drug, 522 (72.0% reported fear of side effects as a major reason for non-uptake. CONCLUSIONS: Uptake of praziquantel in this population is very low. Fear of side effects of praziquantel, lack of knowledge about schistosomiasis transmission and prevention and lack of teacher support are some of the major factors associated with low uptake.
Ana Paula Braz Pereira
Full Text Available School-aged children (6-15 years from the endemic area of Pernambuco were evaluated both as a target group for and an indicator of schistosomiasis control in the community. Parasitological data were drawn from baseline stool surveys of whole populations that were obtained to diagnose Schistosoma mansoni infection. Nineteen representative localities were selected for assessing the prevalence of schistosomiasis among individuals in the following age groups: 0-5, 6-15, 16-25, 26-40 and 41-80 years. For each locality, the prevalence in each age group was compared to that of the overall population using contingency table analysis. To select a reference group, the operational difficulties of conducting residential surveys were considered. School-aged children may be considered to be the group of choice as the reference group for the overall population for the following reasons: (i the prevalence of schistosomiasis in this age group had the highest correlation with the prevalence in the overall population (r = 0.967, (ii this age group is particularly vulnerable to infection and plays an important role in parasite transmission and (iii school-aged children are the main target of the World Health Organization in terms of helminth control. The Schistosomiasis Control Program should consider school-aged children both as a reference group for assessing the need for intervention at the community level and as a target group for integrated health care actions of the Unified Health System that are focused on high-risk groups.
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Perez-Saez, Javier; Mande, Theophile; Ceperley, Natalie; Bertuzzo, Enrico; Mari, Lorenzo; Gatto, Marino; Rinaldo, Andrea
We report about field and theoretical studies on the ecology of the aquatic snails (Bulinus spp. and Biomphalaria pfeifferi) that serve as obligate intermediate hosts in the complex life cycle of the parasites causing human schistosomiasis. Snail abundance fosters disease transmission, and thus the dynamics of snail populations are critically important for schistosomiasis modeling and control. Here, we single out hydrological drivers and density dependence (or lack of it) of ecological growth rates of local snail populations by contrasting novel ecological and environmental data with various models of host demography. Specifically, we study various natural and man-made habitats across Burkina Faso's highly seasonal climatic zones. Demographic models are ranked through formal model comparison and structural risk minimization. The latter allows us to evaluate the suitability of population models while clarifying the relevant covariates that explain empirical observations of snail abundance under the actual climatic forcings experienced by the various field sites. Our results link quantitatively hydrological drivers to distinct population dynamics through specific density feedbacks, and show that statistical methods based on model averaging provide reliable snail abundance projections. The consistency of our ranking results suggests the use of ad hoc models of snail demography depending on habitat type (e.g., natural vs. man-made) and hydrological characteristics (e.g., ephemeral vs. permanent). Implications for risk mapping and space-time allocation of control measures in schistosomiasis-endemic contexts are discussed.
Kalinda, Chester; Chimbari, Moses; Mukaratirwa, Samson
Climate change has been predicted to increase the global mean temperature and to alter the ecological interactions among organisms. These changes may play critical roles in influencing the life history traits of the intermediate hosts (IHs). This review focused on studies and disease models that evaluate the potential effect of temperature rise on the ecology of IH snails and the development of parasites within them. The main focus was on IH snails of schistosome parasites that cause schistosomiasis in humans. A literature search was conducted on Google Scholar, EBSCOhost and PubMed databases using predefined medical subject heading terms, Boolean operators and truncation symbols in combinations with direct key words. The final synthesis included nineteen published articles. The studies reviewed indicated that temperature rise may alter the distribution, optimal conditions for breeding, growth and survival of IH snails which may eventually increase the spread and/or transmission of schistosomiasis. The literature also confirmed that the life history traits of IH snails and their interaction with the schistosome parasites are affected by temperature and hence a change in climate may have profound outcomes on the population size of snails, parasite density and disease epidemiology. We concluded that understanding the impact of temperature on the growth, fecundity and survival of IH snails may broaden the knowledge on the possible effects of climate change and hence inform schistosomiasis control programmes.
Chen, L; Zhong, B; Xu, J; Li, R-Z; Cao, C-L
Schistosomiasis control programme in The People's Republic of China had promoted the mass mobilization of health education in various forms, such as films, drama, traditional opera, poems, slogans, posters, exhibits. This paper is trying to review the impacts of those forms on different endemic settings and targeted populations. In the future, health education and health promotion will still be the effective strategy and one of the interventions in the national control programme for schistosomiasis and other infectious diseases, even in the pre- or posttransmission stages. With the social and economic development and improvement of people's living standard, it is necessary to establish a sustainable mechanism, in combination of health education with health guarantee of improving the quality of life, improving the production and living conditions, changing the unhealthy production methods and lifestyle of the residents in the endemic areas, in order to reach the goal of schistosomiasis elimination in The People's Republic of China. Copyright © 2016 Elsevier Ltd. All rights reserved.
Ni, Ziling; Tan, Xiaodong; Liu, Bei; Ying, Zhaoyu; Gao, Xudong; Yang, Fen
At 9:28 pm on June 1, 2015, the cruise ship "Oriental Star" sank into Yangtze River in Jianli County, with 422 people killed. When the accident occurred, the Chinese government took immediate action and dispatched more than 9000 rescuers. The risk for outbreak of schistosomiasis was increased because of the shipwreck. Obviously it is critical to carry out risk assessment as soon as possible. By means of the Delphi method, the situation was analyzed so that the government could fathom the severity of the accident. Then, through matrix and sigma-plotting (3-dimensional graphics) methods, related authorities performed risk assessment after site investigation. The latest news reported that more than 9000 people were involved in the rescue. The affected river was analyzed and mapped using SigmaPlot software, according to which the possibility, harmfulness, and controllability of the accident were determined to be medium (6), medium (6), and poor (7), respectively. The site of the accident where the cruise ship sank and rescue operations were carried out is a schistosomiasis epidemic area with high mortality and morbidity. The chance of an outbreak of the schistosomiasis epidemic in Jianli County is quite high. To protect people in this county from the epidemic, relevant logistic services should be arranged and all remains should be cleared up carefully. (Disaster Med Public Health Preparedness. 2017;page 1 of 7).
Full Text Available Climate change has been predicted to increase the global mean temperature and to alter the ecological interactions among organisms. These changes may play critical roles in influencing the life history traits of the intermediate hosts (IHs. This review focused on studies and disease models that evaluate the potential effect of temperature rise on the ecology of IH snails and the development of parasites within them. The main focus was on IH snails of schistosome parasites that cause schistosomiasis in humans. A literature search was conducted on Google Scholar, EBSCOhost and PubMed databases using predefined medical subject heading terms, Boolean operators and truncation symbols in combinations with direct key words. The final synthesis included nineteen published articles. The studies reviewed indicated that temperature rise may alter the distribution, optimal conditions for breeding, growth and survival of IH snails which may eventually increase the spread and/or transmission of schistosomiasis. The literature also confirmed that the life history traits of IH snails and their interaction with the schistosome parasites are affected by temperature and hence a change in climate may have profound outcomes on the population size of snails, parasite density and disease epidemiology. We concluded that understanding the impact of temperature on the growth, fecundity and survival of IH snails may broaden the knowledge on the possible effects of climate change and hence inform schistosomiasis control programmes.
Quites, Humberto Ferreira de Oliveira; Abreu, Mery Natali Silva; Matoso, Leonardo Ferreira; Gazzinelli, Andrea
Observational study that examined the quality of the preventive actions for schistosomiasis control in the Brazilian Family Health Strategy (FHS) in an endemic area. Structured questionnaires were used to interview 97 health professionals of the FHS and the Secretary of Health of 25 municipalities belonging to the State Health Department of Pedra Azul, Minas Gerais, Brazil. Models of latent variables were used to define a score to evaluate the quality of the process. The results showed that 57.8% of the FHS teams' actions were unsatisfactory or critical. The professionals did not perform effective activities for the control of the infection and 8.1% did not use the diagnostic methods required by the government. Similarly, the professionals did not receive adequate training for the development of schistosomiasis prevention and control. There was a lack of educational materials to carry out health education activities, and the FHS teams conducted educational activities in only 48% of the schools of municipalities. Less than half of the professionals interviewed knew about the Schistosomiasis Control Program. We concluded that it is necessary to integrate this Program's practices to the FHS, and seek a suitable support of municipal management through pacts and social control.
Moendeg, Kharleezelle J; Angeles, Jose Ma M; Goto, Yasuyuki; Leonardo, Lydia R; Kirinoki, Masashi; Villacorte, Elena A; Rivera, Pilarita T; Inoue, Noboru; Chigusa, Yuichi; Kawazu, Shin-ichiro
The zoonotic characteristic of the human parasite Schistosoma japonicum infecting a significant number of wild and domestic animals highlights the need to develop a unified surveillance in multiple host species for a strengthened schistosomiasis control. It has been shown in several studies that water buffaloes and dogs are considered important reservoirs in the transmission of the schistosome parasite to humans. Recombinant antigens like thioredoxin peroxidase-1 (SjTPx-1) and tandem repeat proteins (Sj1TR, Sj7TR) have been shown to be good diagnostic antigens individually in humans, water buffaloes, and dogs in previous studies. Mixing these antigens together in a cocktail-ELISA might not only improve their diagnostic potentials but rather produce a multi-host species detection means for zoonotic schistosomiasis. In this study, we aimed to develop and optimize cocktail-ELISA by testing different combinations of these recombinant antigens in humans, water buffaloes, and dogs. As compared with the diagnostic potential calculated for each of the three recombinant antigens used, their combination has presented improved specificities, positive predictive values, and kappa values. Using samples collected from various endemic areas in the Philippines, results showed that the combination of SjTPx-1/Sj7TR/Sj1TR has the highest sensitivity in humans (84.1 %), water buffaloes, and dogs (80 %) and specificity (100 %) in all host species. This study therefore suggests the use of cocktail-ELISA in improving the zoonotic surveillance in schistosomiasis endemic areas.
Peter F. Rambau
Full Text Available Schistosomiasis is a communicable disease which commonly involves urinary bladder causing hematuria, or large bowel causing bloody stool. The common species encountered in this lake region surrounding Lake Victoria in Tanzania are Schistosoma haematobium and Schistosoma mansoni. Complications can lead to portal hypertension due portal fibrosis in liver, and fibrosis in lung can lead to pulmonary hypertension; this commonly seen with S. mansoni. Major complications of S. maeametobium are chronic cystitis with squamous metaplasia with subsequent development of squamous cell carcinoma. Involvement of spinal cord causing paraplegia has been observed in S. haematobium. Other unusual pathology of schistosomiasis has been described, such as involvement of the appendix, ovary, prostate, and cervix. Here, we present a case of schistosomiasis in a 9-year-old boy who presented with left scrotal pain for one year which was accompanied by scrotal swelling; surgical exploration was done, and the finding was hydrocele and atrophic testes with nodules on the surface. Histological examination reveals atrophic testis and heavy active granulomatous inflammation with schistosoma eggs consistent with Schistosoma haematobium in the tunica vaginalis.
Gray, Darren J; Thrift, Aaron P; Williams, Gail M; Zheng, Feng; Li, Yue-Sheng; Guo, Jiagang; Chen, Honggen; Wang, Tianping; Xu, Xin Jiang; Zhu, Rong; Zhu, Hongqing; Cao, Chun Li; Lin, Dan Dan; Zhao, Zhen Yuan; Li, Robert S; Davis, George M; McManus, Donald P
Schistosoma japonicum is a major public health concern in the Peoples' Republic of China (PRC), with about 800,000 people infected and another 50 million living in areas at risk of infection. Based on ecological, environmental, population genetic and molecular factors, schistosomiasis transmission in PRC can be categorised into four discrete ecosystems or transmission modes. It is predicted that, long-term, the Three Gorges Dam (TGD) will impact upon the transmission of schistosomiasis in the PRC, with varying degree across the four transmission modes. We undertook longitudinal surveillance from 2002 to 2006 in sentinel villages of the three transmission modes below the TGD across four provinces (Hunan, Jiangxi, Hubei and Anhui) to determine whether there was any immediate impact of the TGD on schistosomiasis transmission. Eight sentinel villages were selected to represent both province and transmission mode. The primary end point measured was human incidence. Here we present the results of this five-year longitudinal cohort study. Results showed that the incidence of human S. japonicum infection declined considerably within individual villages and overall mode over the course of the study. This is also reflected in the yearly odds ratios (adjusted) for infection risk that showed significant (Pdam.
Full Text Available Schistosomal nephropathy has long been related to the hepatosplenic form of schistosomiasis. In the last few years, 24 patients with hepatointestinal schistosomiasis and the nephrotic syndrome were studied. Aiming at evaluating a possible etiologic participation of schistosomiasis in the development of the nephropathy, this group was comparatively studied with a group of 37 patients with idiopathic nephrotic syndrome. Both groups had a different distribution of the histologic lesions. In the group with schistosomiasis there was a statistically significant prevalence of proliferative mesangial glomerulonephritis (33.3%, whereas in the control group there was prevalence of membranous glomerulonephritis (32.4%. On immunofluorescence, IgM was positive in 94.4% of the patients with schistosomiasis versus 55.0% in the control group (pA nefropatia esquistossomótica está classicamente vinculada à fornia hepatoesplênica da esquistossomose. Ao longo dos últimos anos 24 casos de pacientes esquistossomóticos hepato-intestinais e portadores de síndrome nefrótica foram estudados. Com o objetivo de verificar a possível participação etiológica da esquistossomose na gênese da nefropatia, analisamos este grupo comparativamente ao grupo de 37 doentes portadores de síndrome nefrótica idiopática. Ambos os grupos apresentaram distribuição distinta dos tipos histológicos de glomerulopatia. No grupo de esquistossomóticos houve predomínio estatisticamente significante de glomerulonefrite proliferativa mesangial (33.3%, enquanto no grupo controle houve predomínio da glomerulonefrite membranosa (32.4%. A positividade para IgM à imunofluorescência foi de 94.4% nos doentes esquistossomóticos versus 55.0% no grupo controle (p<0.01. No grupo de esquistossomóticos 8 pacientes evidenciaram glomerulonefrite proliferativa mesangial e 5, glomerulonefrite membranoproliferativa. Em ambos os tipos histológicos a imunofluorescência mostrou dep
Full Text Available Foi feita análise de cartazes produzidos por escolares da região nordeste do Brasil, para o II° Concurso Nacional de Cartazes sobre Esquistossomose promovido pelo Programa Especial de Controle de Esquistossomose (PECE do Ministério da Saúde. A análise revelou 4 grandes tipos de cartazes que configuram atitudes distintas diante do problema da Esquistossomose: os cartazes que apresentavam uma atitude puramente negativa diante do problema; os que apresentavam uma atitude puramente positiva; os mistos (combinação dos 2 primeiros tipos, divididos em 2 sub-tipos, que apresentavam: o primeiro, o comportamento indesejado e uma alternativa para este comportamento e o segundo, os elementos do problema sem os relacionar em forma alternativa; e os que apresentavam explicações didáticas ou técnicas sobre esquistossomose. Concluiu-se que as propostas para enfrentar o problema da esquistossomose apresentadas através das mensagens educativas oficiais, refletidas nos cartazes dos escolares, configuraram uma estratégia de mudança radical e, a curto prazo, de comportamentos "primitivos". Sugeriu-se estratégia mais gradual que respeitasse os hábitos e valores culturais vigentes nas comunidades afetadas pela esquistossomose.Posters prepared by students in the northeast of Brazil for the III National Schistosomiasis Poster Contest, sponsored by the Health Ministry's Special Schistosomiasis Control Program, produced four major types of posters expressing different attitudes toward the problem of Schistosomiasis: posters showing a purely negative attitude (ex.; "Do not bathe in contaminated rivers"; those showing a purely positive attitude "Use the latrine"; and the mixed posters, a combination of the first, divided into two subtypes. The first of these subtypes projected a message about an undersirable behavior and an alternative to it; whereas, the second subtype presented the problem's elements but without relating them to alternatives. The last
Zhou, Yi-Biao; Liang, Song; Chen, Yue; Jiang, Qing-Wu
The Three Gorges Dam, located in the largest endemic area of schistosomiasis in China, is one of the world's largest hydroelectric projects to date. Some large-scale hydro projects have resulted in schistosomiasis emergence or re-emergence. Therefore, the dam's potential impact on the transmission of Schistosoma japonicum has raised concerns from medical researchers worldwide. A systematic literature review, coupled with an analysis of data on the water level and snail density in the Yangtze River was conducted to assess the impact of the dam on schistosomiasis transmission after more than 10 years of operation. The dam has significantly altered the water levels in the Yangtze River according to different seasons. These changes directly impact the ecology of the schistosome snail host. Due to the dam, there has been a reduction in the density of Oncomelania snails and/or changes in the distribution of snails. The prevalence of infection with S. japonicum has decreased in the downstream areas of the dam, including in the Dongting and Poyang Lakes. The prevalence of infection with S. japonicum in humans has decreased from 6.80 % in 2002 (before the dam began operating) to 0.50 % in 2012, and the number of people infected with S. japonicum have decreased from 94 208 in 2002 to 59 200 in 2011 in the Poyang Lake region. The presence of the dam does not seem to affect snail breeding or the prevalence of schistosomiasis in the Three Gorges Reservoir. Overall, the Three Gorges Dam has significantly contributed to changes in hydrology after more than 10 years of the dam operating. The changes caused by the dam, together with integrated control of schistosomiasis, might be accelerating the progress towards eliminating the transmission of S. japonicum in the middle and lower reaches of the Yangtze River. Despite the positive effect the dam is having in controlling S. japonicum transmission, continued surveillance is required to monitor the future ecological impacts of the
Zeng, Huan; Yang, Xiaowei; Meng, Siying; Wang, Hong; Tang, Xiaojun; Tang, Wenge; Zeng, Shu; Jeschke, Sandra; Wang, Yang
Schistosomiasis is a severe public health problem in China. It has been predicted that the ecological changes caused by the "Three Gorges Dam", the world's largest hydropower project, could potentially aggravate the spread of schistosomiasis in the area. This study focused on investigating (a) local residents' knowledge on the potential risks of schistosomiasis and (b) the capability of local health personnel in preventing schistosomiasis. A quantitative survey combined with qualitative interviews was conducted in three counties of the reservoir area during November and December 2008. A total of 1386 inhabitants and 180 local health personals participated in questionnaire survey; 18 inhabitants, 21 health professionals, and 8 local government officials were interviewed. Of the surveyed inhabitants, 66.3% had no access to safe drinking water; 47.9% had water-contact regularly through farming or swimming; 58.7% did not have hygienic toilets; and only 13.7% used methane for energy. Besides, only 3.8% of the inhabitants had knowledge scores higher than 6 points within the range 0-10. Educational level, occupation and income were significant predictors of knowledge score (P<0.05). Only about 5% of the inhabitants had some knowledge on schistosomiasis. Among health professionals surveyed, 6.7% had college or higher education; 26.7% had prior schistosomiasis control experience; 75.6% did not receive any relevant training in the past year; and only 52.2% had basic knowledge of schistosomiasis. The logistic regression analysis identified occupation and time at work as significant factors to their knowledge level (P<0.05). Moreover, the surveillance work was often severely hindered by a shortage of funding, and challenged by monitoring of migrant population. There were very limited training opportunities for the health workers, and almost no health education for inhabitants, if any, neither efficient nor effective. Although there were multiple risks for potential Schistosoma
Use of a new glass microfibre histamine release method to study the modulation of the host response in human schistosomiasis mansoni. Individuals with different degrees of exposure to the disease show differing antibody biological function
Satti, M.Z.; Ebbesen, F.; Vennervald, B.
A new glass microfibre histamine release method was used to study the modulation of the host response in human schistosomiasis mansoni to improve our understanding of the role of basophils in the development of immunity in schistosomiasis mansoni. The histamine release from umbilical cord blood b...
Adewunmi, C O; Gebremedhin, G; Becker, W; Olurunmola, F O; Dörfler, G; Adewunmi, T A
A cross sectional survey of schistosomiasis, intestinal parasite infections and pattern of schistosomiasis transmission was undertaken in four rural villages around the Erinle dam, Nigeria. The prevalence of Schistosoma haematobium ranged from 10% to 60%. 30% of infected school children excreted over 50 eggs/10 ml urine and high rates of haematuria, proteinuria, leucocyturia and nitrites in urine were observed in infected children and the villagers. Prevalence of infection with S. mansoni ranged from 11.4% to 36.8%. Intensity of infection based on geometric mean eggs/gram of faeces ranged between 100 and 545.7 eggs/g. Malacological surveys showed that Biomphalaria pfeifferi was the predominant potential snail hosts recovered at all the contact sites. Higher infections with schistosome parasites were also recorded for B. pfeifferi than Bulinus globosus. The pattern of transmission of schistosomiasis by the snails is consistent and makes incorporation of community-based focal application of a molluscicide such as Tetrapleura tetraptera in integrated control of schistosomiasis feasible in the area. Prevalence and intensity with Ascaris lumbricoides was high. The highest prevalence was 68.9% while the highest intensity of infection was 2,440.9 eggs/gram of faeces. Multiple infections occured with various combinations of Ascaris lumbricoides, hookworm, S. haematobium, Fasciola gigantica, S. mansoni, and Entamoeba histolytica (as double, triple or quadruple infections). The results suggest an integrated approach to the control of schistosomiasis and intestinal parasites in this part of the country.
Norseth, Hanne M.; Ndhlovu, Patricia D.; Kleppa, Elisabeth; Randrianasolo, Bodo S.; Jourdan, Peter M.; Roald, Borghild; Holmen, Sigve D.; Gundersen, Svein G.; Bagratee, Jayanthilall; Onsrud, Mathias; Kjetland, Eyrun F.
Background Schistosoma (S.) haematobium is a neglected tropical disease which may affect any part of the genital tract in women. Female genital schistosomiasis (FGS) may cause abnormal vaginal discharge, contact bleeding, genital tumours, ectopic pregnancies and increased susceptibility to HIV. Symptoms may mimic those typical of sexually transmitted infections (STIs) and women with genital schistosomiasis may be incorrectly diagnosed. An expert consensus meeting suggested that the following findings by visual inspection should serve as proxy indicators for the diagnosis of schistosomiasis of the lower genital tract in women from S. haematobium endemic areas: sandy patches appearing as (1) single or clustered grains or (2) sandy patches appearing as homogenous, yellow areas, or (3) rubbery papules. In this atlas we aim to provide an overview of the genital mucosal manifestations of schistosomiasis in women. Methodology/Principal findings Photocolposcopic images were captured from women, between 1994 and 2012 in four different study sites endemic for S. haematobium in Malawi, Zimbabwe, South Africa and Madagascar. Images and specimens were sampled from sexually active women between 15 and 49 years of age. Colposcopic images of other diseases are included for differential diagnostic purposes. Significance This is the first atlas to present the clinical manifestations of schistosomiasis in the lower female genital tract. It will be freely available for online use, downloadable as a presentation and for print. It could be used for training purposes, further research, and in clinical practice. PMID:25412334
Karen Claire Kosinski
Full Text Available Abstract Background Surface water contaminated with human waste may transmit urogenital schistosomiasis (UGS. Water-related activities that allow skin exposure place people at risk, but public health practitioners know little about why some communities with access to improved water infrastructure have substantial surface water contact with infectious water bodies. Community-based mixed-methods research can provide critical information about water use and water infrastructure improvements. Methods Our mixed-methods study assessed the context of water use in a rural community endemic for schistosomiasis. Results Eighty-seven (35.2 % households reported using river water but not borehole water; 26 (10.5 % reported using borehole water but not river water; and 133 (53.8 % households reported using both water sources. All households are within 1 km of borehole wells, but tested water quality was poor in most wells. Schistosomiasis is perceived by study households (89.3 % to be a widespread problem in the community, but perceived schistosomiasis risk fails to deter households from river water usage. Hematuria prevalence among schoolchildren does not differ by household water use preference. Focus group data provides context for water preferences. Demand for improvements to water infrastructure was a persistent theme; however, roles and responsibilities with respect to addressing community water and health concerns are ill-defined. Conclusions Collectively, our study illustrates how complex attitudes towards water resources can affect which methods will be appropriate to address schistosomiasis.
Ultrasonography (US) is suitable for diagnosing schistosomiasis-related organic pathology and is particularly useful to assess its evolution after therapy and/or interruption of exposure to the Schistosoma parasites. Evolution of pathology after treatment: Regression of hepatic abnormalities in Schistosma mansoni-infected children and adolescents has been observed already from 7 months post-therapy on. This does, however, not occur in all cases: individual differences are great ranging from spontaneous regression of pathology without treatment to persistence of pathology lasting for years after therapy even without re-infection. Intensity and duration of exposure, different parasite strains, patients' age and genetic background all influence the evolution of pathology. In communities at continuous exposure to S. mansoni infection, repeated re-treatment is required to control hepatosplenic morbidity. In Schistosoma japonicum infection, changes around the portal tree may regress, but characteristic diffuse abnormalities described as 'network pattern' abnormalities do not resolve. In Schistosoma haematobium infection bladder abnormalities and urinary tract obstruction frequently resolve after treatment. Clinically relevant pathology may resurge from 1 year after therapy on if exposure continues. Subjects with more advanced pathology before therapy, appear to be at higher risk of pathology re-appearance. Evolution of pathology after interruption of exposure to schistosomiasis: Knowledge on the evolution of pathology induced by S. mansoni is limited to some reports in emigrants and to the experience of ultrasonographists working in areas, where transmission has been partially interrupted. Due to the longevity of the parasite, infection may last for many years. Even after elimination of the parasites severe pathology may persist for long. In S. haematobium infection spontaneous healing after interruption of re-exposure may occur, but cases have been reported where
Vitor Coutinho Carneiro
Full Text Available Treatment and control of schistosomiasis relies on the only available drug, praziquantel, and the search for alternative chemotherapeutic agents is therefore urgent. Egg production is required for the transmission and immunopathology of schistosomiasis and females of S. mansoni lay 300 eggs daily. A large fraction of the total mRNA in the mature female worm encodes one eggshell protein, Smp14. We report that the nuclear receptors SmRXR1 and SmNR1 regulate Smp14 transcription through the recruitment of two histone acetyltransferases (HATs, SmGCN5 and SmCBP1. The treatment of HEK293 cells with histone deacetylase (HDAC inhibitors (NaB or TSA produced an 8-fold activation of the SmRXR1/SmNR1-mediated Smp14 promoter activity. Incubation with synthetic HAT inhibitors, including PU139, significantly impaired the Smp14 promoter activity in these cells. Worm pairs cultivated in the presence of PU139 exhibited limited expression of Smp14 mRNA and protein. ChIP analysis demonstrated chromatin condensation at the Smp14 promoter site in worms treated with PU139. ChIP also revealed the presence of H3K27me3 and the absence of RNA Pol II at the Smp14 promoter region in the PU139-treated worms. Most significantly, the PU139-mediated inhibition of Smp14 expression resulted in a significant number of abnormal eggs as well as defective eggs within the ootype. In addition, scanning electron microscopy revealed structural defects and unformed eggshells, and vitelline cell leakage was apparent. The dsRNAi-targeting of SmGCN5 or SmCBP1 significantly decreased Smp14 transcription and protein synthesis, which compromised the reproductive system of mature female worms, egg-laying and egg morphology. Our data strongly suggest that the inhibition of Smp14 expression targeting SmGCN5 and/or SmCBP1 represents a novel and effective strategy to control S. mansoni egg development.
Márcio Martins Machado
Full Text Available A ultra-sonografia representa uma importante contribuição no diagnóstico da forma hepatoesplênica da esquistossomose. A ultra-sonografia permite a identificação das principais alterações, como espessamento periportal, perivesicular, aumento do lobo hepático esquerdo, redução do lobo hepático direito e esplenomegalia. Adicionalmente, os padrões hemodinâmicos podem ser avaliados com o Doppler, sendo possível a análise das veias porta, mesentérica superior e esplênica, além de facilitar o estudo dos vasos venosos colaterais. Em áreas endêmicas, a ultra-sonografia assume papel de destaque, sendo superior à avaliação clínica na identificação da hepatoesplenomegalia e possibilitando o acompanhamento dos pacientes submetidos a tratamento clínico. Neste trabalho, os autores apresentam uma revisão dos principais achados sonográficos e ao Doppler da esquistossomose hepatoesplênica, sendo demonstrada, também, a relação destes achados com os aspectos clínico-patológicos desta doença.Ultrasound represents an important contribution to the diagnosis of hepatosplenic mansonic schistosomiasis. Abnormalities such as hyperechoic fibrotic bands along the portal vessels, volumetric reduction of the right hepatic lobe, enlargement of the left lobe, perivesicular fibrotic thickening and splenomegaly can be recognized. Moreover, the hemodynamic status of the portal venous system may also be evaluated by Doppler analysis, including the identification of collateral veins and portosystemic venous shunts. In endemic areas, ultrasound is of great value in the identification of hepatosplenomegaly, allowing follow-up of patients under clinical treatment. This review presents the ultrasonographic and Doppler features of hepatosplenic schistosomiasis. The relationship between these findings and the clinical and pathological characteristics of this disease are also discussed.
José C Sousa-Figueiredo
Full Text Available In 2012 the WHO formally recognised that infants and preschool children are at significant risk of schistosomiasis and qualify for treatment with praziquantel (PZQ. Targeted surveys determining both the performance and safety of this drug are now needed in endemic areas. We have formally assessed parasitological cure and putative side-effects in a prospective cohort of Schistosoma mansoni-infected children (aged 5 months-7 years old in lakeshore settings of Uganda.From a total of 369 children found to be egg-patent for intestinal schistosomiasis, 305 were followed-up three to four weeks after PZQ treatment and infection status re-assessed. Separately, a previously tested side-effect questionnaire was employed before and 24 hours after PZQ treatment to assess incidence and amelioration of symptoms in young children and their mothers. While the overall observed parasitological cure was 56.4%, a significant difference was found between a sub-set of children who had a history of multiple PZQ treatments (between one and four in an 18 month period, where cure rate was 41.7%, and those who had never received treatment (cure rate was 77·6%. PZQ proved to be safe, with only mild reported side effects which cleared within a month after treatment. Prevalence of reported symptoms was significantly lower in children than in mothers, and fewer side-effects were reported upon subsequent rounds of PZQ treatment.Our findings show that PZQ treatment of young children resulted in satisfactory cure rates, and marked reduction in egg-output, with only mild and transient reported side-effects. However, the cure rate is clearly lower in younger children and those with history of previous treatment. Cure rate, but not egg reduction rate, was also lower in children with heavier pre-intervention infection intensity. With chemotherapy now recommended as a long-term strategy for disease control in young children, research into optimising the periodicity of targeted
Brandt Carlos Teixeira
Full Text Available The usual histology report of hepatic fibrosis in patients with hepatosplenic schistosomiasis mansoni presents no association with hemodynamic and clinical liver parameters. Histomorphometry is adding a new tool of investigation for measuring density of portal fibrosis in these patients. This investigation was set up for assessing a possible agreement between the well-accepted international classification and the fibrosis density grades measured by histomorphometry. Thirty-five children and equal number of adults were included in this study. All patients underwent splenectomy and ligature of the left gastric vein. Histology findings were assessed in surgical liver biopsy stained with Masson trichrome. The official histology report was used as reference. The histomorphometric studies were done by semi-automatic morphometry. The mean percentage (X of portal fibrosis plus or minus one standard deviation (SD was classified as grade II (7.06% up to 34.72%; grade I was up to 7.06%; and grade III above 34.72%. Although, not reaching statistical significance, there is a tendency of the fibrosis to be more intense in children than adults (X±SD - 22.02±13.46% versus 20.63%±15.33% "t" = 0.379 p>0.05. Seven out of nine (77.8% patients classified as grade I, by morphometry, had the same result on the official report, however, two (22.2% were described as grade III. Sixteen out of forty-four (36.4% classified as grade II on morphometry had the same classification as the histology grade, but, twenty seven (61.4% were classified as grade III and one (2.3% as grade I. Fifteen (21.4% out of 70 patients had grade III on both classifications, but, two (11.8% out of seventeen G III on morphometry were grade II. The kappa (k measurement of agreement between both classification was k = 0.319, showing a fair strength of association. The histomorphometric measurements of Symmers fibrosis in surgical patients with mansonic schistosomiasis partially support the report
Olliaro, Piero L; Vaillant, Michel; Hayes, Daniel J; Montresor, Antonio; Chitsulo, Lester
Schistosomiasis is known to occur in preschool-aged children, but achieving accurate dosing of praziquantel in its current form is challenging. While waiting for a paediatric formulation, there is a need to develop a means for using the available products to treat this age group. Current 600-mg tablets are differently scored to give units of 150 mg (a quarter of a tablet) or 300 mg (half a tablet). We examined several dosing schemes to dose accurately (40-60 mg/kg) children aged 3-72 months (weight range 4-25 kg, based on available weight-for-age growth references from sub-Saharan Africa and Brazil, n = 106,230). Adequate dosing can be achieved with formulations that can be split into four 150 mg quarters for children weighing 5 kg or more, and with tablets than can be split into two 300 mg halves for children weighing 10 kg or more. Giving ½ tablet for 5-7 kg; ¾ tablet for 8-10 kg; 1 tablet for 11-15 kg; 1 ½ tablet for 16-21 kg; and two tablets for 22-25 kg will have 100% of subjects correctly dosed within the target 40-60 mg/kg range. Formulations that can be divided into four parts (to give 150 mg increments) are preferred for children weighing less than 11 kg; the same dosing can be applied with 600 mf praziquantel formulations that can be divided into four quarters or two halves from 11 kg body weight. © 2013 John Wiley & Sons Ltd The World Health Organization retains copyright and all other rights in the manuscript of this [Practical dosing of praziquantel for schistosomiasis in preschool-aged children] as submitted for publication.
Wan, Chunpeng; Jin, Fen; Du, Youqin; Yang, Kang; Yao, Liangliang; Mei, Zhigang; Huang, Weifeng
In schistosomiasis, egg deposition in the liver contributes to the formation of hepatic granuloma and fibrosis, which are the most serious clinical pathological features. It has been proposed that activation of the nuclear factor kappa B (NF-κB) signaling pathways is closely associated with the development of hepatic granuloma and fibrosis. Genistein has been shown to inhibit the activity of NF-κB signaling pathways, which might be a potential agent to protect against Schistosoma japonicum egg-induced liver granuloma and fibrosis. In this study, liver granuloma and fibrosis were induced by infecting BALB/c mice with 18 ± 3 cercariae of S. japonicum. At the beginning of egg granuloma formation (early phase genistein treatment from 4 to 6 weeks after infection) or after the formation of liver fibrosis (late phase genistein treatment from 6 to 10 weeks after infection), the infected mice were injected with genistein (25, 50 mg/kg). The results revealed that genistein treatment significantly decreased the extent of hepatic granuloma and fibrosis in infected mice. The activity of NF-κB signaling declined sharply after the treatment with genistein, as evidenced by the inhibition of NF-κB-p65, phospho-NF-κB-p65, and phospo-IκB-α expressions, as well as the expression of IκB-α and the messenger RNA (mRNA) expression of inflammatory cytokines (MCP1, TNFα, IL1β, IL4, IL10) mediated by NF-κB signaling pathways in the early phase of the infection. Moreover, western blot and immunohistochemistry assays demonstrated that the contents of α-smooth muscle actin (α-SMA) and transforming growth factor-β were dramatically reduced in liver tissue under the treatment of genistein in the late phase of the infection. At the same time, the mRNA expression of MCP1, TNFα, and IL10 was inhibited markedly. These results provided evidence that genistein reduces S. japonicum egg-induced liver granuloma and fibrosis, at least partly due to decreased NF-κB signaling, and
Full Text Available Schistosomiasis japonica has long been endemic in the People's Republic of China. In the 1950s, the number of the infected persons was estimated at 10 million; infected snail habitats were estimated at more than 14 billion square metres and infected cattle at 1.2 million. After schistosomiasis control measures were carried out, it was a great success. According to the survey of 1989, infected persons were estimated at 0.95 million; infected snails at 3.47 billion and infected cattle at about 0.1 million.These results compared with those of the 1950s show big reductions in prevalence rates 90.5%, 75.2% and 91.6%, respectively. At present, the disease is a threat in the marshland and lake regions and the high mountainous regions. To maintain the success achieved in effective control and to bring the yet endemic marshland and lake regions and mountainous areas under control are hard and long-term tasks confronting the People's Republic of China.A esquistossomose japonica, há séculos, é considerada endêmica na República Popular da China. Em 1950, estimou-se em 10 milhões o número de pessoas infectadas; focos de caramujos infectados ocupavam 14 bilhões de metros quadrados e era de 1,2 milhões o número de gado infectado. As medidas de controle da esquistossomose alcançaram grande sucesso. De acordo com o levantamento realizado em 1989, o número de pessoas infectadas decresceu para 950 mil, focos de caramujos infectados ocupavam 3,47 bilhões de metros quadrados e o número de gado contaminado passou a 100 mil. Estes resultados, quando comparados ao de 1950, mostraram grande redução, sendo de respectivamente, 90,5%, 75,2% e 91,6%. Atualmente, a endemia está presente nas áreas pantanosas, em lagos e nas regiões montanhosas. A manutenção do sucesso obtido e o controle efetivo nas áreas ainda endêmicas é um desafio que exigirá trabalho árduo e a longo prazo na República Popular da China.
Omedo, Martin; Ogutu, Michael; Awiti, Alphonce; Musuva, Rosemary; Muchiri, Geoffrey; Montgomery, Susan P; Secor, W Evan; Mwinzi, Pauline
Compliance with mass drug administration (MDA) can be affected by rumors and mistrust about the drug. Communication campaigns are an effective way to influence attitudes and health behaviors in diverse public health contexts, but there is very little documentation about experiences using health communications in schistosomiasis control programs. A qualitative study was conducted with community health workers (CHWs) as informants to explore the effect of a health communication campaign on their experiences during subsequent praziquantel MDA for schistosomiasis. Discussions were audio-recorded, transcribed verbatim, translated into English where applicable, and analyzed thematically using ATLAS.ti software. According to the CHWs, exposure to mass media messages improved awareness of the MDA, which in turn, led to better treatment compliance. Our findings suggest that communication campaigns influence health behaviors and create awareness of schistosomiasis control interventions, which may ultimately improve praziquantel MDA. © The American Society of Tropical Medicine and Hygiene.
Stothard, J Russell; Ameri, Haji; Khamis, I Simba; Blair, Lynsey; Nyandindi, Ursuline S; Kane, Richard A; Johnston, David A; Webster, Bonnie L; Rollinson, David
To confirm the local endemicity of Schistosoma haematobium on Mafia Island, Tanzania, conjoint parasitological and malacological surveys were undertaken in July 2006 with parasitological investigations supplemented with case-history questionnaires. A total of 238 children (125 girls and 113 boys, mean age of 13.9 years) across 9 primary schools were examined. The prevalence of micro-haematuria and egg-patent infection was 18.1% (CI95=9.6-33.6) and 4.2% (CI95=1.9-7.6), respectively but a strong female bias was observed for micro-haematuria (5.6F:1M) contrasting with a strong male bias for the presence of eggs (1F:4M). All egg-patent infections were of light-intensity (Mafia and Unguja islands as well as DNA barcoding of snails and schistosomes. B. nasutus was shown refractory to infection. With the substantial travel to and from Mafia, the refractory nature of local snails and evidence from DNA barcoding in schistosomes and snails, we conclude that urogenital schistosomiasis is an imported infection. Copyright © 2012 Elsevier B.V. All rights reserved.
Eduardo José Andrade Lopes
Full Text Available Paciente de 36 anos de idade, proveniente de zona endêmica foi admitido com episódios de hematúria macroscópica total e disúria terminal. A citoscopia mostrou um tumor exofítico na parede anterior da bexiga, sugestivo de câncer. A biópsia revelou esquistossomose mansônica. Ressecção transuretral confirmou o diagnóstico. O paciente foi clinicamente tratado com oxamniquine, obtendo cura. O caso apresentado nesse trabalho enfatiza que nem todos os tumores de bexiga com hematúria microscópica são cânceres de bexiga.A 36-year-old patient, proceeding from an endemic area was admitted with episodes of total microscopic hematuria and terminal dysuria. Cytoscopy showed a protuberant tumor in the bladder anterior wall, suggestive of cancer. Biopsy revealed schistosomiasis mansoni. Transurethral resection confirmed the diagnosis. The patient was clinically treated and cured with oxamniquine. The case presented in this work emphasizes that not all the tumors of bladder with microscopic hematuria are bladder cancers.
Phillips, S.M.; Linette, G.P.; Doughty, B.L.; Byram, J.E.; Von Lichtenberg, F.
These studies assessed the roles of subpopulations of T lymphocytes in inducing and modulating resistance to schistosomiasis and thereby influencing subsequent morbidity. C57BL/6 mice were depleted in vivo of Lyt-1+, Lyt-2+, and L3T4+ cells by the daily administration of monoclonal antibodies. The development of protective immunity, induced by exposure to irradiated Schistosoma mansoni cercariae as expressed in depleted animals, was compared to that demonstrated in undepleted, normal, and congenitally athymic C57BL/6 mice. The development of morbidity was determined by spleen weight, portal pressure and reticuloendothelial system activity. The results indicated that depletion of specific subpopulations of T lymphocytes minimally affected the primary development of parasites; however, depletion strongly influenced the development of resistance to the parasite and subsequent morbidity due to infection. Depletion of T lymphocytes by anti-Lyt-1+ or anti-L3T4+ antibody decreased the development of resistance, antibody and delayed-type hypersensitivity directed against schistosome antigens. Morbidity due to disease was increased. Depletion of Lyt-2+ cells produced opposite changes with augmented resistance and reduced morbidity. Congenitally athymic mice developed minimal resistance and morbidity. Moreover, resistance was inversely related to the morbidity shown by a given animal. These studies indicate that the development of protective immunity to S. mansoni cercariae is regulated by discrete subpopulations of T lymphocytes. The feasibility of decreasing morbidity by increasing specific immunologically mediated resistance is suggested.
Elmorshedy, Hala; Tanner, Marcel; Bergquist, Robert N; Sharaf, Soraya; Barakat, Rashida
A double-blind, randomized controlled trial was conducted in an endemic focus for Schistosoma mansoni in Kafr El-Sheikh Governorate, Northern Nile Delta, Egypt, to evaluate the prophylactic effect of artemether (ART) given in conjunction with praziquantel (PZQ). The study encompassed 913 primary school children randomly assigned to two treatment groups PZQ/ART and PZQ/ART-placebo. At baseline, both groups received 40 mg/kg body weight of PZQ twice four weeks apart, after which one group received 6 mg/kg body weight of ART every 3 weeks in 5 cycles during the transmission season and the other group received ART-placebo. At the end of the study, prevalence of infection among the PZQ/ART was approximately half that of the PZQ/ART-placebo group, i.e. 6.7% versus 11.6%, and incidence of new infections for the PZQ/ART was 2.7% versus 6.5% for the PZQ/ART-placebo. In conclusion, PZQ/ART combined therapy might be considered as an adjunct measure against human schistosomiasis, by specifically reducing transmission and therefore contribute to disease elimination. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.
Ibrahim, Abdalla M; Abdel-Gawad, Mahfouz M; El-Nahas, Hanan A; Osman, Nadia S
In the search for new molluscicidal plants for controlling the snail vectors of schistosomiasis, laboratory evaluation was made to assess the molluscicidal activity of Agave angustifolia and Pittosporum tobira plants against Biomphalaria alexandrina snails. Results indicated that both plants have promising molluscicidal activity as the LC90 of the dry powder of both plants was 120 ppm. Both plants showed marked cercaricidal and miracidicidal potencies against S. mansoni larvae. The LC90 of both plants (120 ppm) killed most B. alexandrina eggs within 24 h of exposure. The sub-lethal concentrations of both plants markedly suppressed the survival rate of B. alexandrina snails and the mortality increased with increasing the concentrations and the exposure period up to 10 successive weeks. The accumulative toxic effect of these concentrations was continuous during the recovery period. Also, the reproductive rates of exposed snails were greatly affected even through the recovery period. This depression in reproductive ability of snails was accompanied by histological damage in the hermaphrodite glands of exposed snails. Meanwhile, the growth of snails was estimated weekly and it showed great inhibition in exposed snails comparing with the control ones.
H. L. Lenzi
Full Text Available During the schistosomiasis infection there is a [quot ]dance of the cells[quot ], varying from site to site and related to the time of infection. 1 - Eosinophil levels exhibit a bimodal pattern, with the first peak related to the egg deposition and maturation and increased Kupfferian hyperplasia; the second peak precedes the death of some adult worms; 2 - The peritoneal eosinophilic levels are inversely proportional to the blood eosinophilic levels; 3 - Eosinopoiesis in the bone marrow begins at day 40, reaching the highest levels at day 50 and coincides with hepatic eosinophilic and neutrophilic metaplasia; 4 - Peritoneal mast cell levels present a bimodal pattern similar to the blood eosinophils, and inverse to the peritoneal eosinophils. They also show a cyclic behaviour within the hepatic and intestinal granulomas. Integral analysis of the events related to the eosinophils in the blood, bone marrow, peritoneal cavity and hepatic and intestinal granulomas allows the detection of two important eosinophilic phases: the first is due to mobilization and redistribution of the marginal pool and the second originates from eosinophilic production in the bone marrow and liver. The productive phase is characterized by an increase in the number of eosinophils and monocyte/macrophages, and a decrease in neutrophils and stabilization of megakariocytes and erithroid lineages.
Leonardo, Lydia R; Acosta, Luz P; Olveda, Remigio M; Aligui, Gemiliano D L
Schistosomiasis japonica continues to remain a public health problem in the Philippines affecting 10 out of 16 regions with 6.7 million people at risk mostly farmers and fisher folks. Early efforts focused on snail control in the absence of an effective drug against the disease. Discovery of praziquantel shifted control focus from the expensive snail control to a more manageable one involving case detection and treatment. At present, the government's objective is to reduce morbidity by chemotherapy and supplemented with environmental sanitation, health education, and mollusciciding. In the past, external funds infused into government control programs helped a lot in bringing down prevalence rates of the disease in many highly endemic areas. The end of this foreign assistance has expectedly affected implementation of the programs bringing fears of a possible resurgence in many endemic areas. Such anxiety is also founded on the perennial problems of low disease awareness among people at risk, aggravated security problem, poverty and the negative effects of a devolved set-up in the health care delivery system. Experts suggest that the national health department should be more aggressive in dealing with the disease in terms of ensuring implementation and of continuously searching for better and more improved methods of control. Any new strategy should always consider the devolved set up of the health department.
Kong, Shibo; Tan, Xiaodong; Deng, Zhiqing; Xie, Yaofei; Yang, Fen; Zheng, Zengwang
Snail control is a key link in schistosomiasis control, but no unified methods for eliminating snails have been produced to date. This study was conducted to explore an engineering method for eliminating Oncomelania hupensis applicable to urban areas. The engineering specifications were established using the Delphi method. An engineering project based on these specifications was conducted in Hankou marshland to eliminate snails, including the transformation of the beach surface and ditches. Molluscicide was used as a supplement. The snail control effect was evaluated by field investigation. The engineering results fulfilled the requirements of the design. The snail density decreased to 0/0.11m 2 , and the snail area dropped to 0m 2 after the project. There was a statistically significant difference in the number of frames with snails before and after the project (Pengineering specifications for environmental modification were successfully established. Environmental modification, mainly through beach and ditch remediation, can completely change the environment of Oncomelania breeding. This method of environmental modification combined with mollusciciding was highly effective at eliminating snails. Copyright © 2017 Elsevier B.V. All rights reserved.
Full Text Available The acute toxemic form of schistosomiasis mansoni is studied under anatomic and clinical point of view, according to classification made by Neves, Raso and Bagliolo in 1975. The first phase is characterized by the following facts: cutaneous (immediate and late manifestations; high fever or in progressive elevation; intense diaphoresis abdominal disconfort; intense acquous diarrhea; dehidratation; loss of weight, dry cough; painful hepatosplenomegaly; discreet lymphademegaly, progressive increase of blood leucocytes and eosinophisles; radiological pulmonary alterations; absence of alterations in serum protein and hepatic functional tests; the hepatic function byopsy shows focus of acute hepatitis. The second stage or properly named toxemic period was clinically characterized by the neat aggravation of the previously observed phenomena. At last, the evolutive course of the disease has implication derived not only of the worm's presence, but from the intense dissemination of eggs in the tissue. In the pre-laying phase one studied the forms of cercarian dermatitis, prodromic and innapparent. In the post laying phase, the properly named acute toxemic form, with its types: pseudocholeraic, pseudotyphous, pseudodysenteric-bacillary, pseudonophritic, pseudoenterovirotic, the reactivated, the ischemic enterocolitis and others; whenever possible clinical and anatomic correlation will be made.
Li, Ying; Mei, Lihong; Qiang, Jinwei; Ju, Shuai; Zhao, Shuhui
Portal-systemic encephalopathy (PSE) is classified as type B hepatic encephalopathy. Portal-systemic shunting rather than liver dysfunction is the main cause of PSE in chronic hepatic schistosomiasis japonicum (HSJ) patients. Owing to lack of detectable evidence of intrinsic liver disease, chronic HSJ patients with PSE are frequently clinically undetected or misdiagnosed, especially chronic HSJ patients with covert PSE (subclinical encephalopathy). In this study, we investigated whether magnetic resonance spectroscopy (MRS) could be a useful tool for diagnosing PSE in chronic HSJ patients. Magnetic resonance (MR) T1-weighted imaging, diffusion-weighted imaging, and MRS were performed in 41 chronic HSJ patients with suspected PSE and in 21 age-matched controls. The T1 signal intensity index (T1SI) and apparent diffusion coefficient (ADC) value were obtained in the Globus pallidus. Liver function was also investigated via serum ammonia and liver function tests. Higher T1SI and ADC values, increased lactate and glutamine levels, and decreased myo-inositol were found in the bilateral Globus pallidus in chronic HSJ patients with PSE. No significantly abnormal serum ammonia or liver function tests were observed in chronic HSJ patients with PSE. On the basis of these findings, we propose a diagnostic procedure for PSE in chronic HSJ patients. This study reveals that MRS can be useful for diagnosing PSE in chronic HSJ patients.
Brandt, C T; Maciel, D T; Caneca, O A; Castro, C M; Araújo, L B
Autotransplantation of spleen tissue has been done, in the past ten years, in children with schistosomiasis mansoni with bleeding varices. The purposes of this investigation were: (1) to study the morphology and function of the remnant spleen tissue; (2) to quantify the production of tuftsin; and (3) to assess the immune response to pneumococcal vaccine of these patients. Twenty three children, who underwent splenectomy and autologous implantation of spleen tissue into the greater omentum were included in this investigation. The average postoperative follow-up is five years. Splenosis was proved by colloid liver-spleen scans. Search for Howell-Jolly bodies assessed the filtration function. Tuftsin and the titer of pneumococcal antibodies were quantified by ELISA. Splenosis was evident in all children; however, it was insufficient in two. Howell-Jolly bodies were found only in these two patients. The mean tuftsin serum concentration (335.0 +/- 29.8 ng/ml) was inside the normal range. The immune response to pneumococcal vaccination was adequate in 15 patients; intermediate in four; and inadequate in four. From the results the following conclusions can be drawn: splenosis was efficient in maintaining the filtration splenic function in more than 90% and produced tuftsin inside the range of normality. It also provided the immunologic splenic response to pneumococcal vaccination in 65% of the patients of this series.
Carlos Teixeira Brandt
Full Text Available Autotransplantation of spleen tissue has been done, in the past ten years, in children with schistosomiasis mansoni with bleeding varices. The purposes of this investigation were: (1 to study the morphology and function of the remnant spleen tissue; (2 to quantify the production of tuftsin; and (3 to assess the immune response to pneomococcal vaccine of these patients. Twenty three children, who underwent splenectomy and autologous implantation of spleen tissue into the greater omentum were included in this investigation. The average postoperative follow-up is five years. Splenosis was proved by colloid liver-spleen scans. Search for Howell-Jolly bodies assessed the filtration function. Tuftsin and the titer of pneumococcal antibodies were quantified by ELISA. Splenosis was evident in all children; however, it was insufficient in two. Howell-Jolly bodies were found only in these two patients. The mean tuftsin serum concentration (335.0 ± 29.8 ng/ml was inside the normal range. The immune response to pneumococcal vaccination was adequate in 15 patients; intermediate in four; and inadequate in four. From the results the following conclusions can be drawn: splenosis was efficient in maintaining the filtration splenic function in more than 90% and produced tuftsin inside the range of normality. It also provided the immunologic splenic response to pneumococcal vaccination in 65% of the patients of this series.
Klar, Kathrin; Perchermeier, Sophie; Bhattacharjee, Sonakshi; Harb, Hani; Adler, Thure; Istvanffy, Rouzanna; Loffredo-Verde, Eva; R A Oostendorp, Robert; Renz, Harald; Prazeres da Costa, Clarissa
Schistosomiasis is a nontransplacental helminth infection. Chronic infection during pregnancy suppresses allergic airway responses in offspring. We addressed the question whether in utero exposure to chronic schistosome infection (Reg phase) in mice affects B-cell and T-cell development. Therefore, we focused our analyses on T-cell differentiation capacity induced by epigenetic changes in promoter regions of signature cytokines in offspring. Here, we show that naïve T cells from offspring of schistosome infected female mice had a strong capacity to differentiate into TH 1 cells, whereas TH 2 differentiation was impaired. In accordance, reduced levels of histone acetylation of the IL-4 promoter regions were observed in naïve T cells. To conclude, our mouse model revealed distinct epigenetic changes within the naïve T-cell compartment affecting TH 2 and TH 1 cell differentiation in offspring of mothers with chronic helminth infection. These findings could eventually help understand how helminths alter T-cell driven immune responses induced by allergens, bacterial or viral infections, as well as vaccines. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Christiane Leal Corrêa
Full Text Available Maternal malnutrition during the lactation period in early development may have long-term programming effects on adult offspring. We evaluated the combined effects of parasitological behaviour and histopathological features and malnutrition during lactation. Lactating mice and their pups were divided into a control group (fed a normal diet of 23% protein, a protein-restricted group (PR (fed a diet containing 8% protein and a caloric-restricted group (CR (fed according to the PR group intake. At the age of 60 days, the offspring were infected with Schistosoma mansoni cercariae and killed at nine weeks post-infection. Food intake, body and liver masses, leptinaemia, corticosteronaemia, collagen morphometry and neogenesis and the cellular composition of liver granulomas were studied. PR offspring showed reduced weight gain and hypophagia, whereas CR offspring became overweight and developed hyperphagia. The pre-patent period was longer (45 days in both programmed offspring as compared to controls (40 days. The PR-infected group had higher faecal and intestinal egg output and increased liver damage. The CR-infected group showed a lower number of liver granulomas, increased collagen neogenesis and a higher frequency of binucleate hepatocytes, suggesting a better modulation of the inflammatory response and increased liver regeneration. Taken together, our findings suggest that neonatal malnutrition of offspring during lactation affects the outcome of schistosomiasis in mice.
Thiengo Silvana C
Full Text Available In order to elaborate a planorbid chart of the State of Rio de Janeiro a survey of freshwater gastropods in the Metropolitan Mesoregion of this State was performed and revealed the occurrence of 20 species: Antillorbis nordestensis (Lucena, 1954; Biomphalaria glabrata (Say, 1818; Biomphalaria schrammi (Crosse, 1864; Biomphalaria straminea (Dunker, 1848; Biomphalaria tenagophila (Orbigny, 1835; Burnupia sp.; Drepanotrema anatinum (Orbigny, 1835; Drepanotrema cimex (Moricand, 1839; Drepanotrema lucidum (Pfeiffer, 1839; Ferrissia sp.; Gundlachia ticaga (Marcus & Marcus, 1962; Heleobia davisi Silva & Thomé, 1985; Lymnaea columella Say, 1817; Melanoides tuberculatus (Müller, 1774; Physa cubensis Pfeiffer, 1839; Physa marmorata Guilding, 1828; Pomacea sp.; Pomacea canaliculata (Lamarck, 1822; Pomacea lineata (Spix, 1827 and Pomacea sordida (Swainson, 1823. Among the planorbid species B. tenagophila was the most frequent, occurring in all municipalities surveyed. The present study extends the distribution of B. straminea in the State of Rio de Janeiro and reports new records for A. nordestensis, B. schrammi, G. ticaga, H. davisi and the genera Burnupia and Ferrissia. An account about the current transmission areas of schistosomiasis mansoni in this Mesoregion is presented as well.
Full Text Available Acute cases of schistosomiasis have been found on the coastal area of Pernambuco, Brazil, due to environmental disturbances and disorderly occupation of the urban areas. This study identifies and spatially marks the main foci of the snail host species, Biomphalaria glabrata on Itamaracá Island. The chaotic occupation of the beach resorts has favoured the emergence of transmission foci, thus exposing residents and tourists to the risk of infection. A database covering five years of epidemiological investigation on snails infected by Schistosoma mansoni in the island was produced with information from the geographic positioning of the foci, number of snails collected, number of snails tested positive, and their infection rate. The spatial position of the foci were recorded through the Global Positioning System (GPS, and the geographical coordinates were imported by AutoCad. The software packages ArcView and Spring were used for data processing and spatial analysis. AutoCad 2000 was used to plot the pairs of coordinates obtained from GPS. Between 1998 and 2002 5009 snails, of which 12.2% were positive for S. mansoni, were collected in Forte Beach. A total of 27 foci and areas of environmental risk were identified and spatially analyzed allowing the identification of the areas exposed to varying degrees of risk.
J. R. Lambertucci
Full Text Available Three distinct syndromes caused by schistosomiasis have been described: cercarial dermatitis or swimmer's itch, acute schistosomiasis or Katayama fever, and chronic schistosomiasis. Complications of acute schistosomiasis have also been reported. The absence of a serological marker for the acute stage has hindered early diagnosis and treatment. Recently, an ELISA test using KLH (keyhole limpet haemocyanin as antigen, has proved useful in differentiating acute from chronic schistosomiasis mansoni. Clinical and experimental evidence indicate that steroids act synergistically with schistosomicides in the treatment of Katayama syndrome. In this paper, clinical, diagnostic and therapeutic features of acute schistosomiasis are updated.A esquistossomose apresenta-se clinicamente em três formas distintas: dermatite cercariana, esquistossomose aguda ou febre de Katayama e esquistossomose crônica. Há na literatura relatos de complicações da fase aguda. A ausencia de um marcador sorológico simples e confiável tem dificultado o diagnóstico precoce e, como consequência, o tratamento adequado de pacientes na fase aguda da doença. Recentemente, o teste de ELISA, realizado com o antígeno KLM (hemocianina do caramujo Megathura crenulata, tem se mostrado util na identificação dos pacientes com febre de Katayama. Evidências clínicas e experimentais apontam no sentido de uma ação sinérgica entre os corticosteróides e os esquistossomicidas no tratamento da esquistossomose toxêmica. Neste artigo, alguns aspectos clínicos, diagnósticos e terapêuticos da esquistossomose aguda são atualizados.
Soyannwo, M A; Lagundoye, S B; Lucas, A O
After studying two rural communities with varing endemicity of urinary schistosomiasis by total cross-sectional population survey, a stratified sample was obtained using defined criteria. Plain X-ray abdomen and intravenous pyelogram were carried out on the sample. Findings on plain X-ray of the abdomen, using the usual parameters of psoas and kidney shadows in the Nigerian, indicate that the two communities studied are similar but urinary calculi and urinary tract distortion are significantly more prominent in the community with the higher endemicity of urinary schistosomiasis.
[Cost-effectiveness evaluation on comprehensive control measures carrying out in schistosomiasis endemic areas with regard to different layers of administrative villages stratified by infection situation of human and domestic animals. II Correlation analysis of costs and inputs with changes of schistosomiasis endemic situation in inner embankment of marshland and lake regions from 2006 to 2013].
Hu, He-hua; Yu, Qing; Zhang, Xia; Cao, Chun-li; Li, Shi-zhu; Zhu, Hong
To investigate the correlations between inputs and costs and endemic situation of schistosomiasis in inner embankment, so as tb provide the references for the strategy optimization of schistosomiasis control. Jiangling County was selected as the study field. The correlatibn and regression analyses were applied to analyze the endemic situation of schistosomiasis in Jiangling County from 2006 to 2013. The methods of two-stages least squares and path analysis were applied to analyze the impacts between costs and inputs and endemic situation of schistosomiasis. The adjusted infection rate of population, number of bovines and Oncomelania hupensis snail areas reduced by 77.42%, 76.34% and 19.43%, respectively in Jiangling County from 2006 to 2013. The correlations between the infection rate of snails and the population positive rates of blood and fecal exams, and the infection rate of bovines were significant (all P costs and the population positive rate of fecal exams and the infection rates of bovines and snails (all P costs and the population positive rate by blood exams (P > 0.05). The inputs at county level had an impact on the population positive rate of blood exams; the costs of comprehensive treatment had an impact on the population positive rate of fecal exams; the costs of human labor and measures for exams and treatments had an impact on the infeiction rate of bovines; the inputs at national level and the costs of measures for exams and treatments had an impact on the infection rate of snails (all P costs of schistosomiasis control were related to the epidemic situation of schistosomiasis in Jiangling County from 2006 to 2013; therefore, it is necessary to develop a comprehensive surveillance system as substitute for the current indexes on schistosomiasis control.
Ricardo de Amorim Correa
Full Text Available A esquistossomose mansoni é a terceira doença parasitária endêmica mais prevalente do mundo. Estima-se que mais de 200 milhões de pessoas estejam infectadas com uma das espécies do parasita Schistosoma. Dessas, 270.000 pessoas (4,6% são portadoras de hipertensão arterial pulmonar, que é associada à forma hepatoesplênica da doença. Essa alta prevalência coloca a hipertensão pulmonar esquistossomótica como a causa mais frequente de hipertensão pulmonar no mundo. Entretanto, o tratamento dirigido especificamente ao acometimento vascular pulmonar não está ainda estabelecido. Relatamos o caso de uma paciente portadora dessa doença que foi tratada com um inibidor de fosfodiesterase-5 (sildenafil com resultados satisfatórios.Schistosomiasis mansoni is the third most prevalent endemic parasitic disease in the world. It is estimated that over 200 million people are infected with parasites belonging to one of the Schistosoma species. Of those, 270,000 people (4.6% suffer from pulmonary arterial hypertension, which is associated with the hepatosplenic form of the disease. This high prevalence makes schistosomiasis-associated pulmonary hypertension the leading cause of pulmonary hypertension worldwide. However, no specific treatment for the pulmonary vascular component of the disease has yet been devised. We report the case of a patient with schistosomiasis-associated pulmonary hypertension who was treated satisfactorily with a phosphodiesterase-5 inhibitor (sildenafil.
Brand, G; Brand, I
This review covers the following aspects: Cancer associated with asbestos and other fibers: Epidemiology. - Cancer types and location (mesothelioma; bronchogenic carcinoma; cancer of the upper respiratory tract; abdominal cancer). - Experimental asbestos cancer. - Other kinds of fibers and cancer (wool and cotton; glass; talc; others). - Cancer determining or influencing factors (individual predisposition; species susceptibility; type of material; shape and size of fibers; smoking). - Preneoplastic signs in man (fibrosis; ferruginous bodies; pleural plaques; milky spots). - Preneoplastic development in animals. - Fiber effects on cell cultures (macrophages; fibroblasts). Cancer associated with schistosomiasis: Epidemiology. - Patient age and cancer latency. - Pathology. - Foreign body reaction and preneoplastic development. Scar cancer. Foreign body cancer: In man. - Experimental (species differences in susceptibility; individual genetic differences in tumor incidence and latency; influence of sex, age, nutrition; tumor histopathology and ultrastructure; tumor growth, invasiveness, metastases, transplantability, immunology; search for tumor viruses). - Properties of foreign body materials in relation to tumorigenicity (chemical and physical properties; size and shape; surface properties; porosity). - Investigations and findings concerning the origin of foreign body sarcomas (the foreign body reaction; search for foci of tumor origin; an analytical method; monoclonal tumor origin; heterogenicity of carcinogenic events; surface dependency; identification of originator cells; time and location of the emergence of tumor originator cells; the carcinogenic initiation event; surface-independent and dependent preneoplastic maturation; the carcinogenic role of the foreign body). - Earlier hypotheses and theories in the light of new experimental findings. The results of experimental foreign body tumorigenesis in relation to foreign body-, asbestos-, schistosomiasis-, and
Mwinzi Pauline NM
Full Text Available Abstract Background Schistosome and soil-transmitted helminth (STH infections are recognized as major global public health problems, causing severe and subtle morbidity, including significant educational and nutritional effects in children. Although effective and safe drugs are available, ensuring access to these drugs by all those at risk of schistosomiasis and STHs is still a challenge. Community-directed intervention (CDI has been used successfully for mass distribution of drugs for other diseases such as onchocerciasis and lymphatic filariasis. A national control programme is yet to be instituted in Kenya and evidence for cost-effective strategies for reaching most affected communities is needed. This study evaluated the effectiveness and feasibility of the CDI strategy in the control of schistosomiasis and STHs, in East Uyoma location, Rarieda district, a community of western Kenya that is highly endemic for both infections. Results Pre-treatment prevalence of S. mansoni averaged 17.4% (range 5-43% in the entire location. Treatment coverage in different villages ranged from 54.19 to 96.6% by community drug distributor (CDD records. Assessment from a household survey showed coverage of 52.3 -91.9% while the proportion of homesteads (home compounds covered ranged from 54.9-98.5%. Six months after one round of drug distribution, the prevalence levels of S. mansoni, hookworm and Trichuris trichura infections were reduced by 33.2%, 69.4% and 42.6% respectively. Conclusions This study shows that CDI is an accepted and effective strategy in the mass treatment of schistosomiasis and STH infections in resource constrained communities in Kenya and may be useful in similar communities elsewhere. A controlled trial comparing CDI and school based mass drug administration to demonstarte their relative advantages is ongoing.
Wikman-Jorgensen, Philip Erik; Henríquez-Camacho, César Augusto; Serrano-Villar, Sergio; Pérez-Molina, Jose Antonio
Objective Efficacy of artemisinin derivatives alone or in combination compared to praziquantel alone for the treatment of urinary schistosomiasis in schoolchildren. Methods Randomized clinical trials comparing praziquantel with artemisinin derivatives in the treatment of urinary schistosomiasis in schoolchildren were included. Medline, EMBASE, LILACS, CENTRAL, African Index Medicus, and Scielo were searched. We also analyzed the abstracts of the main conferences on infectious diseases and tropical medicine during the years 2009–2011. Google Scholar and OpenSIGLE were also searched. The last search was performed in July 2012. The primary endpoint was the cure rate. The main outcome data were retrieved using a standardized form; three independent researchers (WP, HC, and SS) performed the search, retrieved data, and evaluated the risk of bias. Disagreements were resolved by discussion. Risk ratios were used and heterogeneity was evaluated. A fixed or random-effects model was used according to the results of heterogeneity testing. An intention-to-treat analysis was done. Data were analyzed using Revman 5.0.24 (Copenhagen: The Nordic Cochrane Centre). Results Seven studies were selected for full text review and only five studies were finally included. The cure rate for praziquantel was superior to that of artesunate (RR: 1.66; 95% CI: 1.18–2.33). Artesunate was not clearly superior to placebo (artesunate versus placebo, RR: 3.21; 95% CI: 0.50–20.74). Combination of artesunate with praziquantel could prove more beneficial than praziquantel alone (RR: 1.15; 95% CI: 1.01–1.31). The frequency of adverse events was equivalent for both drugs (praziquantel versus artesunate, RR: 1.11; 95% CI: 0.80–1.55). Conclusions Our meta-analysis showed that praziquantel was significantly more effective than artesunate for the treatment of urinary schistosomiasis in schoolchildren. Artesunate at best had a marginal role in combination therapy. PMID:23265611
José Carlos Sousa-Figueiredo
Full Text Available BACKGROUND: Malaria, schistosomiasis and geohelminth infection are linked to maternal and child morbidity and mortality in sub-Saharan Africa. Knowing the prevalence levels of these infections is vital to guide governments towards the implementation of successful and cost-effective disease control initiatives. METHODOLOGY/PRINCIPAL FINDINGS: A cross-sectional study of 1,237 preschool children (0-5 year olds, 1,142 school-aged children (6-15 year olds and 960 women (>15 year olds was conducted to understand the distribution of malnutrition, anemia, malaria, schistosomiasis (intestinal and urinary and geohelminths in a north-western province of Angola. We used a recent demographic surveillance system (DSS database to select and recruit suitable households. Malnutrition was common among children (23.3% under-weight, 9.9% wasting and 32.2% stunting, and anemia was found to be a severe public health problem (i.e., >40%. Malaria prevalence was highest among preschool children reaching 20.2%. Micro-hematuria prevalence levels reached 10.0% of preschool children, 16.6% of school-aged children and 21.7% of mothers. Geohelminth infections were common, affecting 22.3% of preschool children, 31.6% of school-aged children and 28.0% of mothers. CONCLUSIONS: Here we report prevalence levels of malaria, schistosomiasis and geohelminths; all endemic in this poorly described area where a DSS has been recently established. Furthermore we found evidence that the studied infections are associated with the observed levels of anemia and malnutrition, which can justify the implementation of integrated interventions for the control of these diseases and morbidities.
Sousa-Figueiredo, José Carlos; Gamboa, Dina; Pedro, João Mário; Fançony, Cláudia; Langa, António Justino; Soares Magalhães, Ricardo J.; Stothard, J. Russell; Nery, Susana Vaz
Background Malaria, schistosomiasis and geohelminth infection are linked to maternal and child morbidity and mortality in sub-Saharan Africa. Knowing the prevalence levels of these infections is vital to guide governments towards the implementation of successful and cost-effective disease control initiatives. Methodology/Principal Findings A cross-sectional study of 1,237 preschool children (0–5 year olds), 1,142 school-aged children (6–15 year olds) and 960 women (>15 year olds) was conducted to understand the distribution of malnutrition, anemia, malaria, schistosomiasis (intestinal and urinary) and geohelminths in a north-western province of Angola. We used a recent demographic surveillance system (DSS) database to select and recruit suitable households. Malnutrition was common among children (23.3% under-weight, 9.9% wasting and 32.2% stunting), and anemia was found to be a severe public health problem (i.e., >40%). Malaria prevalence was highest among preschool children reaching 20.2%. Micro-hematuria prevalence levels reached 10.0% of preschool children, 16.6% of school-aged children and 21.7% of mothers. Geohelminth infections were common, affecting 22.3% of preschool children, 31.6% of school-aged children and 28.0% of mothers. Conclusions Here we report prevalence levels of malaria, schistosomiasis and geohelminths; all endemic in this poorly described area where a DSS has been recently established. Furthermore we found evidence that the studied infections are associated with the observed levels of anemia and malnutrition, which can justify the implementation of integrated interventions for the control of these diseases and morbidities. PMID:22493664
Martial L Ndeffo Mbah
Full Text Available Epidemiological data from Zimbabwe suggests that genital infection with Schistosoma haematobium may increase the risk of HIV infection in young women. Therefore, the treatment of Schistosoma haematobium with praziquantel could be a potential strategy for reducing HIV infection. Here we assess the potential cost-effectiveness of praziquantel as a novel intervention strategy against HIV infection.We developed a mathematical model of female genital schistosomiasis (FGS and HIV infections in Zimbabwe that we fitted to cross-sectional data of FGS and HIV prevalence of 1999. We validated our epidemic projections using antenatal clinic data on HIV prevalence. We simulated annual praziquantel administration to school-age children. We then used these model predictions to perform a cost-effectiveness analysis of annual administration of praziquantel as a potential measure to reduce the burden of HIV in sub-Saharan Africa.We showed that for a variation of efficacy between 30-70% of mass praziquantel administration for reducing the enhanced risk of HIV transmission per sexual act due to FGS, annual administration of praziquantel to school-age children in Zimbabwe could result in net savings of US$16-101 million compared with no mass treatment of schistosomiasis over a ten-year period. For a variation in efficacy between 30-70% of mass praziquantel administration for reducing the acquisition of FGS, annual administration of praziquantel to school-age children could result in net savings of US$36-92 million over a ten-year period.In addition to reducing schistosomiasis burden, mass praziquantel administration may be a highly cost-effective way of reducing HIV infections in sub-Saharan Africa. Program costs per case of HIV averted are similar to, and under some conditions much better than, other interventions that are currently implemented in Africa to reduce HIV transmission. As a cost-saving strategy, mass praziquantel administration should be prioritized
Carlos Teixeira Brandt
Full Text Available Schistosomiasis mansoni affects the hepatic functional reserve. Clinical treatment with oxamniquine is not 100% effective and there has been found strain of this parasite resistant to this drug. The aims of this investigation were: (1 to examine the presence of residual parasite burden after medical and surgical treatment on adolescents with surgical schistosomiasis mansoni and (2 to assess the effect on the hepatic functional reserve in patients with and without residual infection. Twenty nine children with hepatosplenic schistosomiasis mansoni and bleeding esophageal varices were treated with oxamniquine. They underwent splenectomy, ligature of the left gastric vein and autologous implantation of spleen tissue into the greater omentum. After a mean post-operative follow up of five years they underwent rectal biopsy for schistosomotic egg search. They were divided in patients with and without infection. In 20 patients the submucosal egg search was negative, however, in 9 it was positive. The hepatic functional reserve in the patients without infection was as follows: 17 were Child-Pugh A and 3 Child-Pugh B. In the patients who were still infected 6 were Child-Pugh A and 3 Child-Pugh B. The chi2 analysis of the hepatic functional reserve showed chi2 = 3.19 - p= 0.07. From the results the following conclusion can be drawn: residual infection or reinfection in the follow up period had not interfered with the distribution of the hepatic functional reserve of the patients in this series. However, there was a trend for a decrease of this parameter in patients with residual infection.
Uffe Christian Braae
Full Text Available Taenia solium is found throughout sub-Saharan Africa and co-endemic with schistosomiasis in many regions. Taenia solium leads to taeniosis and neurocysticercosis - the leading cause of preventable epilepsy globally. This study aimed to assess the effects of the National Schistosomiasis Control Programme on prevalence of taeniosis and porcine cysticercosis over a four year period in Tanzania. School-based mass drug administration (MDA of praziquantel was carried out based on schistosomiasis endemicity. Four human and five porcine cross-sectional surveys were carried out from 2012 to 2015 in Mbozi and Mbeya district in Tanzania. Three rounds of school-based MDA of praziquantel were delivered in Mbozi and two in Mbeya. The prevalence of taeniosis and porcine cysticercosis was estimated annually. Stool samples were collected from humans and prevalence of taeniosis estimated by copro-Ag-ELISA. Blood samples from pigs were collected to estimate cysticercosis prevalence by Ag-ELISA. “Track-and-treat” of taeniosis cases was carried out after each survey. In total 12082 stool samples and 4579 porcine serum samples were collected. Significantly fewer children (≤15 from Mbozi were infected throughout the study than children from Mbeya who showed a significant decrease in copro-Ag prevalence after the first treatment only. During the final survey in Mbozi the prevalence of taeniosis in adults (1.8% was significantly lower (p = 0.031, OR 0.40, CI: 0.17–0.89, compared to baseline (4.1%. The prevalence of porcine cysticercosis (8% had also dropped significantly (p = 0.002, OR 0.49, CI: 0.32–0.76 in this district compared to baseline (13%, whereas no significant difference was seen in Mbeya compared to baseline. The study suggests that three rounds of MDA targeting schistosomiasis in school-aged children combined with ‘track-and-treat’ contributed to a reduction in prevalence of T. solium in this population, and also had a spillover effect on
Samwel Bushukatale Ng`weng`weta
Full Text Available Objective: To examine the magnitude of Schistosoma haematobium (S. haematobium infection and the factors associated with exposure of preschool children in Kigogo Ward, Kinondoni District, Dar es Salaam. Methods: A quantitative cross-sectional survey of Class I pupils (preschool-age in 2015 was carried out from May to June 2016 to examine the prevalence and intensity of S. haematobium infection and associated factors. Urine samples were examined for haematuria, S. haematobium eggs and intensity. Parents or guardians were interviewed on their awareness and level of knowledge on urinary schistosomiasis disease (symptoms, mode of transmission, treatment and prevention, as well as their perceived risk of infection to young children. Potential sites of transmission were identified and searched for Bulinus spp., snails and the activities that exposed young children to infection were recorded. Results: A total of 424 pupils and 408 female parents or guardians were recruited. Haematuria was detected in 51 (12.0% pupils, S. haematobium eggs were observed in 8 (1.9% pupils and all were light infection. Bulinus spp., snails were identified mostly at cross-points of rivers. The large majority (91.7% of parents or guardians were aware of urinary schistosomiasis disease, but three quarter (76% did not consider it as a health problem. More than two thirds (71.3% reported that anybody could get urinary schistosomiasis; two thirds (65.9% reported that infection was likely to be acquired at cross-points of rivers. The large majority (> 90% had the notion that young children could be exposed; and all the activities that might lead a child to come into contact with potentially infested waters were judged to be risk factors. The larger majority (83.6% had a high level of knowledge on urinary schistosomiasis (transmission, symptoms, availability of modern treatment and the preventive measures, reflecting the ongoing advocacy campaigns. Conclusions: Young children left
Full Text Available Data herein reported and discussed refer to vaccination with the recombinant Fatty Acid Binding protein family member of the Schistosomes, called Sm14, discovered and developed under a Brazilian platform leaded by the Oswaldo Cruz Foundation, from the Health Ministry in Brazil, undertaken to assess safety and immunogenicity in healthy volunteers. This paper reviews past and recent outcomes of developmental phases of the Sm14 based anti Schistosomiasis vaccine addressed to, ultimately, impact transmission of the second most prevalent parasitic endemic disease worldwide.
Full Text Available BACKGROUND: Mapping the distribution of schistosomiasis is essential to determine where control programs should operate, but because it is impractical to assess infection prevalence in every potentially endemic community, model-based geostatistics (MBG is increasingly being used to predict prevalence and determine intervention strategies. METHODOLOGY/PRINCIPAL FINDINGS: To assess the accuracy of MBG predictions for Schistosoma haematobium infection in Ghana, school surveys were evaluated at 79 sites to yield empiric prevalence values that could be compared with values derived from recently published MBG predictions. Based on these findings schools were categorized according to WHO guidelines so that practical implications of any differences could be determined. Using the mean predicted values alone, 21 of the 25 empirically determined 'high-risk' schools requiring yearly praziquantel would have been undertreated and almost 20% of the remaining schools would have been treated despite empirically-determined absence of infection - translating into 28% of the children in the 79 schools being undertreated and 12% receiving treatment in the absence of any demonstrated need. CONCLUSIONS/SIGNIFICANCE: Using the current predictive map for Ghana as a spatial decision support tool by aggregating prevalence estimates to the district level was clearly not adequate for guiding the national program, but the alternative of assessing each school in potentially endemic areas of Ghana or elsewhere is not at all feasible; modelling must be a tool complementary to empiric assessments. Thus for practical usefulness, predictive risk mapping should not be thought of as a one-time exercise but must, as in the current study, be an iterative process that incorporates empiric testing and model refining to create updated versions that meet the needs of disease control operational managers.
Arthur Soares Souza, Jr.
Full Text Available A 35 years old rural worker presented with a 15 days history of progressive dyspnea, associated with dry cough, mialgia and fever. Few days before the symptoms, he had swim in a river. The chest radiographs demonstrated bilateral reticule-nodular infiltrates. The high-resolution CT showed patchy areas of ground-glass attenuation, irregular interlobular septal thickening, intralobular interstitial thickening, and small nodules, which are confluent in some regions. All the laboratorial investigation were negative. The open lung biopsy shows parenchymal granulomatous inflammation, and numerous schistosome ova. Resumo: Paciente masculino, de 35 anos, trabalhador rural, apresentando-se com história de dispneia progressiva, tosse seca, mialgia e febre, com evolução de 15 dias. Relatava ter nadado num rio, recentemente. As radiografias de tórax mostravam infiltração retículo-nodular bilateral. A tomografia computadorizada de alta resolução evidenciava áreas esparsas de atenuação em vidro fosco, espessamento irregular de septos in- terlobulares e do interstício intralobular e pequenos nódulos, confluentes em algumas regiões. Os exames laboratoriais eram normais. Biópsia pulmonar a céu aberto demonstrou inflamação parenquimatosa granulomatosa, com presença de ovos de esquistossoma. Key-words: Acute schistosomiasis, high-resolution computed tomography, parasitic infection, lungs, Palavras-chave: Esquistossomose aguda, tomografia computadorizada de alta resolução, infecção parasitária, pulmões
Enk, Martin J; Caldeira, Roberta L; Carvalho, Omar S; Schall, Virginia T
Recently, the booming rural tourism in endemic areas of the state of Minas Gerais was identified as a contributing factor in the dissemination of the infection with Schistosoma mansoni. This article presents data from six holiday resorts in a rural district approximately 100 km distant from Belo Horizonte, MG, Brazil, where a possibly new and until now unperceived way of transmission was observed. The infection takes place in swimming pools and little ponds, which are offered to tourists and the local population for fishing and leisure activities. The health authorities of the district reported cases of schistosomiasis among the local population after visiting these sites. As individuals of the non-immune middle class parts of the society of big urban centers also frequent these resorts, infection of these persons cannot be excluded. A malacological survey revealed the presence of molluscs of the species Biomphalaria glabrata and Biomphalaria straminea at the resorts. The snails (B. glabrata) of one resort tested positive for S. mansoni. In order to resolve this complex problem a multidisciplinary approach including health education, sanitation measures, assistance to the local health services, and evolvement of the local political authorities, the local community, the tourism association, and the owners of the leisure resorts is necessary. This evidence emphasizes the urgent need for a participative strategic plan to develop the local tourism in an organized and well-administered way. Only so this important source of income for the region can be ensured on the long term without disseminating the disease and putting the health of the visitors at risk.
Hsue, S.Y.; Xu, S.T.; He, Y.X.; Shi, F.H.; Shen, W.; Hsue, H.F.; Osborne, J.W.; Clarke, W.R.
Vaccination of Chinese bovines (cattle and buffaloes) against Schistosomiasis japonica with 36 kR gamma-irradiated schistosomula was done for laboratory challenge and for field trials in China. Altogether, 61 bovines were used. All experimental animals were vaccinated 2-3 times with 10,000 irradiated schistosomula per time. For the laboratory challenge, all experimental and control cattle were challenged with 500 normal cercariae and each buffalo, with 2,000 cercariae. The laboratory-challenged bovines were killed after 54-57 days of challenge; the bovines for the field trial in the lightly endemic area, after 5 months in the field; and the bovines for the field trial in the heavily endemic area, after 58-63 days. When the animals were killed, the number of mature worms in the vaccinated (experimental) and non-vaccinated (control) animals was recorded and the percentage of worm reduction in each group was calculated. The first group, consisting of three vaccinated and three non-vaccinated cattle, was given a laboratory challenge; the worm reduction was 71.6%. The second group, consisting of two vaccinated and three non-vaccinated buffaloes, was also given a laboratory challenge; the worm reduction was 74.4%. The third group, consisting of seven vaccinated and eight non-vaccinated buffaloes, was utilized in a field trial in a lightly endemic area; the worm reduction was 75.6%. The fourth group, consisting of eight vaccinated and nine non-vaccinated cattle, and the fifth group, consisting of nine vaccinated and nine non-vaccinated buffaloes, were pastured in a heavily endemic area. The worm reduction was 65.1% in the fourth group and 75.7% in the fifth group.
Ludmila Nakamura Rapado
Full Text Available BACKGROUND: Schistosomiasis is one of the most significant diseases in tropical countries and affects almost 200 million people worldwide. The application of molluscicides to eliminate the parasite's intermediate host, Biomphalaria glabrata, from infected water supplies is one strategy currently being used to control the disease. Previous studies have shown a potent molluscicidal activity of crude extracts from Piper species, with extracts from Piper tuberculatum being among the most active. METHODS AND FINDINGS: The molluscicidal activity of P. tuberculatum was monitored on methanolic extracts from different organs (roots, leaves, fruit and stems. The compounds responsible for the molluscicidal activity were identified using (1H NMR and ESIMS data and multivariate analyses, including principal component analysis and partial least squares. These results indicated that the high molluscicidal activity displayed by root extracts (LC50 20.28 µg/ml was due to the presence of piplartine, a well-known biologically-active amide. Piplartine was isolated from P. tuberculatum root extracts, and the molluscicidal activity of this compound on adults and embryos of B. glabrata was determined. The compound displayed potent activity against all developmental stages of B. glabrata. Next, the environmental toxicity of piplartine was evaluated using the microcrustacean Daphnia similis (LC50 7.32 µg/ml and the fish Danio rerio (1.69 µg/ml. The toxicity to these organisms was less compared with the toxicity of niclosamide, a commercial molluscicide. CONCLUSIONS: The development of a new, natural molluscicide is highly desirable, particularly because the commercially available molluscicide niclosamide is highly toxic to some organisms in the environment (LC50 0.25 µg/ml to D. similis and 0.12 µg/ml to D. rerio. Thus, piplartine is a potential candidate for a natural molluscicide that has been extracted from a tropical plant species and showed less toxic to
Uwem F. Ekpo
Full Text Available Schistosomiasis prevalence data for Nigeria were extracted from peer-reviewed journals and reports, geo-referenced and collated in a nationwide geographical information system database for the generation of point prevalence maps. This exercise revealed that the disease is endemic in 35 of the country’s 36 states, including the federal capital territory of Abuja, and found in 462 unique locations out of 833 different survey locations. Schistosoma haematobium, the predominant species in Nigeria, was found in 368 locations (79.8% covering 31 states, S. mansoni in 78 (16.7% locations in 22 states and S. intercalatum in 17 (3.7% locations in two states. S. haematobium and S. mansoni were found to be co-endemic in 22 states, while co-occurrence of all three species was only seen in one state (Rivers. The average prevalence for each species at each survey location varied between 0.5% and 100% for S. haematobium, 0.2% to 87% for S. mansoni and 1% to 10% for S. intercalatum. The estimated prevalence of S. haematobium, based on Bayesian geospatial predictive modelling with a set of bioclimatic variables, ranged from 0.2% to 75% with a mean prevalence of 23% for the country as a whole (95% confidence interval (CI: 22.8-23.1%. The model suggests that the mean temperature, annual precipitation and soil acidity significantly influence the spatial distribution. Prevalence estimates, adjusted for school-aged children in 2010, showed that the prevalence is <10% in most states with a few reaching as high as 50%. It was estimated that 11.3 million children require praziquantel annually (95% CI: 10.3-12.2 million.
Andrea L Araujo Navas
Full Text Available Spatial modelling of STH and schistosomiasis epidemiology is now commonplace. Spatial epidemiological studies help inform decisions regarding the number of people at risk as well as the geographic areas that need to be targeted with mass drug administration; however, limited attention has been given to propagated uncertainties, their interpretation, and consequences for the mapped values. Using currently published literature on the spatial epidemiology of helminth infections we identified: (1 the main uncertainty sources, their definition and quantification and (2 how uncertainty is informative for STH programme managers and scientists working in this domain.We performed a systematic literature search using the Preferred Reporting Items for Systematic reviews and Meta-Analysis (PRISMA protocol. We searched Web of Knowledge and PubMed using a combination of uncertainty, geographic and disease terms. A total of 73 papers fulfilled the inclusion criteria for the systematic review. Only 9% of the studies did not address any element of uncertainty, while 91% of studies quantified uncertainty in the predicted morbidity indicators and 23% of studies mapped it. In addition, 57% of the studies quantified uncertainty in the regression coefficients but only 7% incorporated it in the regression response variable (morbidity indicator. Fifty percent of the studies discussed uncertainty in the covariates but did not quantify it. Uncertainty was mostly defined as precision, and quantified using credible intervals by means of Bayesian approaches.None of the studies considered adequately all sources of uncertainties. We highlighted the need for uncertainty in the morbidity indicator and predictor variable to be incorporated into the modelling framework. Study design and spatial support require further attention and uncertainty associated with Earth observation data should be quantified. Finally, more attention should be given to mapping and interpreting
Full Text Available Experiences with population-based chemotherapy and other methods for the control of schistosomiasis mansoni in two subsaharan foci are described. In the forest area of Maniema (Zaire, intense transmission of Schistosoma mansoni, high prevalences and intensities of infection, and important morbidity have been documental. Taking into account the limited financial means and the poor logistic conditions, the control strategy has been based mainly on targeted chemotherapy of heavily infected people (>600 epg. After ten years of intervention, prevalences and intensities have hardly been affected, but the initial severe hepatosplenic morbidity has almost disappeared. In Burundi, a national research and control programme has been initiated in 1982. Prevalences, intensities and morbidity were moderate, transmission was focal and erratic in time and space. A more structural control strategy was developed, based on screening and selective therapy, health education, sanitation and domestic water supply. Prevalences and intensities have been considerably reduced, though the results show focal and unpredicatable variations. Transmission and reinfection were not signifcantly affected by chemotherapy alone, and eventual outcome of repeated selective treatment appears to be limited by the sensitivity of the screening method. Intestinal morbidity was strongly reduced by community-based selective treatment, but hepatosplenic enlargement was hardly affected; this is possibly due to the confounding impact of increasing malaria morbidity. The experiences show the importance of local structures and conditions for the development of an adapted control strategy. It is further concluded that population-based chemotherapy is a highly valid tool for the rapid control of morbidity, but should in most operational conditions not be considered as a tool for transmission control. Integration of planning, execution and surveillance in regular health services...
Feng, Jintao; Xu, Rui; Zhang, Xin; Han, Yu; He, Chuanchuan; Lu, Chao; Hong, Yang; Lu, Ke; Li, Hao; Jin, Yamei; Lin, Jiaojiao; Liu, Jinming
Domestic animals infected with Schistosoma japonicum are a major source of infection and play an important role in transmission to humans. A key strategy for the elimination of schistosomiasis is to control the sources of infection. In the present study, we identified a candidate diagnostic antigen-encoding gene, SjMRP1, the putative multidrug resistance protein 1 gene, by screening a cDNA phage display library from 44-day-old S. japonicum worms using IgGs from goat, cattle, and buffalo infected with S. japonicum. We cloned and expressed the fragment of SjMRP1 and subsequently evaluated the diagnostic potential of the recombinant protein rSjMRP1. In the enzyme-linked immunosorbent assay of rSjMRP1 (rSjMRP1-ELISA), the sensitivity in goat, cattle, and buffalo was 95.6% (86/90), 100% (22/22), and 90% (81/90), respectively, and the specificity was 100% (30/30) in goat and cattle and 96.67% (29/30) in buffalo. These results were not significantly different from soluble egg antigen (SEA)-ELISA results. Notably, rSjMRP1-ELISA has no cross reaction with Haemonchus contortus, a most common nematode seen in goat and bovine in China, in 13 infected goats, and with Orientobilhazia turkestanica, which is genetically under Schistosoma, in 36 infected goats; whereas SEA-ELISA showed false positive rate of 15.38% and 83.33% in the two respective animal groups. The results obtained here suggest that rSjMRP1 may be used for diagnosis of S. japonicum infection of domestic animals. Copyright © 2017. Published by Elsevier B.V.
Xu, Rui; Zhao, Deng-yun; Lu, Ke; Hong, Yang; Li, Hao; Lin, Jiao-jiao; Liu, Jin-ming; Xu, Yu-mei; Zhu Chuan-gang
To develop a quick and easy colloidal gold immunochromatography assay (GICA) strip for schistosomiasis diagnosis in domestic animals. The reconstruction of Streptococcal Protein G (SPG) was designed and its gene was subcloned into plasmid pET-28a(+) to express in Escherichia coli. The recombinant SPG was purified and labeled with colloidal gold. The Schistosoma japonicum soluble egg antigen (SEA) and rSPG were blotted on the nitrocellulose membrane for the test line and control line respectively. The specificity, sensitivity and cross-reaction of the strip method were detected. The rSPG was successfully expressed and purified to label with colloidal gold. The colloidal gold immunochromatography assay strips were assembled and they could detect the sera of S. japonicum infected BALB/c mice, New Zealand white rabbits, buffalo and sheep successfully. Besides, the sensitivity of GICA strip was 100% in the sera of mice and the serum of rabbits with S. japonicum infection. The specificity was 100% in the serum of mice and the sera of rabbits with free of infection. The sensitivity was 100% in the sera of sheep with miracidia of S. japonicum hatching from the stool and the specificity was 88.46% in the sera of sheep without that. The sensitivity was 94.44% in the sera of buffalo with miracidia hatching from the stool and the specificity was 100% in the sera of buffalo without that. The cross-reaction rate was 5.88% in Paramphistomum. The GICA strip can successfully detect a variety of S. japonicum infected domestic animals and may be a useful tool for screening on a large scale in the endemic areas.
Hu, Yi; Xiong, Chenglong; Zhang, Zhijie; Luo, Can; Cohen, Ted; Gao, Jie; Zhang, Lijuan; Jiang, Qingwu
We compared changes in the spatial clustering of schistosomiasis in Southwest China at the conclusion of and six years following the end of the World Bank Loan Project (WBLP), the control strategy of which was focused on the large-scale use of chemotherapy. Parasitological data were obtained through standardized surveys conducted in 1999-2001 and again in 2007-2008. Two alternate spatial cluster methods were used to identify spatial clusters of cases: Anselin's Local Moran's I test and Kulldorff's spatial scan statistic. Substantial reductions in the burden of schistosomiasis were found after the end of the WBLP, but the spatial extent of schistosomiasis was not reduced across the study area. Spatial clusters continued to occur in three regions: Chengdu Plain, Yangtze River Valley, and Lancang River Valley during the two periods, and regularly involved five counties. These findings suggest that despite impressive reductions in burden, the hilly and mountainous regions of Southwest China remain at risk of schistosome re-emergence. Our results help to highlight specific locations where integrated control programs can focus to speed the elimination of schistosomiasis in China.
Hu, Yi; Xiong, Chenglong; Zhang, Zhijie; Luo, Can; Ward, Michael; Gao, Jie; Zhang, Lijuan; Jiang, Qingwu
The 10-year (1992-2001) World Bank Loan Project (WBLP) contributed greatly to schistosomiasis control in China. However, the re-emergence of schistosomiasis in recent years challenged the long-term progress of the WBLP strategy. In order to gain insight in the long-term progress of the WBLP, the spatial pattern of the epidemic was investigated in the Yangtze River Valley between 1999-2001 and 2007-2008. Two spatial cluster methods were jointly used to identify spatial clusters of cases. The magnitude and number of clusters varied during 1999-2001. It was found that prevalence of schistosomiasis had been greatly reduced and maintained at a low level during 2007-2008, with little change. Besides, spatial clusters most frequently occurred within 16 counties in the Dongting Lake region and within 5 counties in the Poyang Lake region. These findings precisely pointed out the prior places for future public health planning and resource allocation of schistosomiasis. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
Remigio M. Olveda
Full Text Available Zoonotic schistosomiasis has a long endemic history in the Philippines. Human mass drug administration has been the cornerstone of schistosomiasis control in the country for the past three decades. Recent publications utilizing retrospective national survey data have indicated that the national human prevalence of the disease is <1%, hence the disease is now close to elimination. However, the evidence for such a claim is weak, given that less than a third of the human population is currently being treated annually within endemic zones and only a third of those treated actually swallow the tablets. For those who consume the drug at the single oral dose of 40 mg/kg, the estimated cure rate is 52% based on a recent meta-analysis. Thus, approximately 5% of the endemic human population is in reality receiving the appropriate treatment. To compound this public health problem, most of the bovines in the endemic communities are concurrently infected but are not treated under the current national control programme. Given this evidence, it is believed that the human prevalence of schistosomiasis within endemic regions has been grossly underestimated. Inherent flaws in the reporting of national schistosomiasis prevalence data are reported here, and the problems of utilizing national retrospective data in making geographic information system (GIS risk maps and advising policy makers of the outcomes are highlighted.
Full Text Available Acute schistosomiasis is characterized by pro-inflammatory responses against tissue- or organ-trapped parasite eggs along with granuloma formation. Here, we describe studies in Cx3cr1−/− mice and demonstrate the role of Cx3cr1 in the pathoetiology of granuloma formation during acute schistosomiasis. Mice deficient in Cx3cr1 were protected from granuloma formation and hepatic injury induced by Schistosoma japonicum eggs, as manifested by reduced body weight loss and attenuated hepatomegaly along with preserved liver function. Notably, S. japonicum infection induced high levels of hepatic Cx3cr1 expression, which was predominantly expressed by infiltrating macrophages. Loss of Cx3cr1 rendered macrophages preferentially towards M2 polarization, which then led to a characteristic switch of the host immune defense from a conventional Th1 to a typical Th2 response during acute schistosomiasis. This immune switch caused by Cx3cr1 deficiency was probably associated with enhanced STAT6/PPAR-γ signaling and increased expression of indoleamine 2,3-dioxygenase (IDO, an enzyme that promotes M2 polarization of macrophages. Taken together, our data provide evidence suggesting that CX3CR1 could be a viable therapeutic target for treatment of acute schistosomiasis.
López Bustinduy, A.
Schistosomiasis is a parasitic disease that affects over 100 million children in the world living mostly in sub-Saharan Africa. This thesis explored several aspects of the disease affecting the health of children from two African endemic countries: Kenya and Uganda. Epidemiological work revealed a
Monica Ammon Fernandez
Full Text Available Introduction Schistosomiasis is a parasitic disease of public health concern in Brazil, and the construction of hydroelectric dams, in addition to increasing permanent human settlement and tourism, has created conditions suitable for the establishment of mollusks that can transmit schistosomiasis. Such areas require a number of actions to prevent the establishment of schistosomiasis. This paper reports on a freshwater malacological survey carried out in the geographical area of the Manso Power Plant. Methods Mollusks were collected in 18 municipalities in the State of Mato Grosso between February 2002 and February 2004 (qualitative study and from April 2009 to February 2011 (quantitative study. Results Thirty-one species of mollusks were collected, including newly recorded species (Antillorbis nordestensis and Burnupia ingae. In addition, the geographic distributions of known species, including Biomphalaria straminea, a snail vector of Schistosoma mansoni, were expanded. A total of 4,507 specimens were collected in the APM Manso reservoir (Usina Hidrelétrica de Aproveitamento Múltiplo de Manso during the quantitative study, and Biomphalaria amazonica was found in six of the 10 localities analyzed. The Afroasiatic species Melanoides tuberculata, introduced after February 2009, was the dominant species (relative abundance 94.96%. Conclusions The study area is epidemiologically important due to the occurrence of B. straminea and B. amazonica, which are vectors of schistosomiasis, and M. tuberculata, a snail host of Centrocestus formosanus, which is responsible for centrocestiasis transmission. Observations of M. tuberculata and the exotic freshwater clams Corbicula fluminea and Corbicula largillierti raise concerns about biodiversity.
Full Text Available To improve health education within primary schools, the health education booklet Juma na kichocho was evaluated during a study within 5 schools using key-informant questionnaires that recorded children's knowledge and attitude (KA towards schistosomiasis before and after daily structured-use of booklets. A total of 229 schoolchildren (114 boys : 115 girls of between 11 and 15 years of age were interviewed and re-assessed after a working school week. Existing and putative booklet-induced changes in KA scores for schistosomiasis were compared directly against equivalent KA scores for malaria. In total 47.4% of children were already aware that schistosomiasis was a water-borne disease while only 10.5% knew of its exact aetiology; after booklet intervention these levels increased to 54.6 and 15.7%, respectively. The majority of children still failed, however, to realise that re-infection could take place soon after treatment. While a positive increase was observed for children's total KA questionnaire scores for both malaria and schistosomiasis after booklet intervention, these were not statistically significant. In the context of control, further educational efforts are needed to promote and guide behavioural change, especially in relation to reduction of environmental water contact.
Phillips, David Alexander; Ferreira, José Antonio; Ansah, Deidra; Teixeira, Herica Sa; Kitron, Uriel; Filippis, Thelma de; Alcântara, Marcelo H de; Fairley, Jessica K
Despite public health efforts to reduce the global burden of leprosy, gaps remain in the knowledge surrounding transmission of infection. Helminth co-infections have been associated with a shift towards the lepromatous end of the disease spectrum, potentially increasing transmission in co-endemic areas. Using this biologically plausible association, we conducted a geographic information systems (GIS) study to investigate the spatial associations of schistosomiasis and leprosy in an endemic area of Minas Gerais (MG), Brazil. Data on new cases of Mycobacterium leprae and Schistosoma mansoni infections from 2007-2014 were retrieved from the Brazilian national notifiable diseases information system for seven municipalities in and surrounding Vespasiano, MG. A total of 139 cases of leprosy and 200 cases of schistosomiasis were mapped to a municipality level. For one municipality, cases were mapped to a neighborhood level and a stratified analysis was conducted to identify spatial associations. A relative risk of 6.80 [95% confidence interval (CI) 1.46 - 31.64] of leprosy was found in neighborhoods with schistosomiasis. Incidence rates of leprosy increased with corresponding incidence rates of schistosomiasis, and the temporal trends of both infections were similar. The associations found in this project support the hypothesis that helminth infections may influence the transmission of leprosy in co-endemic areas.
Ran, Lin; Yu, Qilin; Zhang, Shu; Xiong, Fei; Cheng, Jia; Yang, Ping; Xu, Jun-Fa; Nie, Hao; Zhong, Qin; Yang, Xueli; Yang, Fei; Gong, Quan; Kuczma, Michal; Kraj, Piotr; Gu, Weikuan; Ren, Bo-Xu; Wang, Cong-Yi
Acute schistosomiasis is characterized by pro-inflammatory responses against tissue- or organ-trapped parasite eggs along with granuloma formation. Here, we describe studies in Cx3cr1(-/-) mice and demonstrate the role of Cx3cr1 in the pathoetiology of granuloma formation during acute schistosomiasis. Mice deficient in Cx3cr1 were protected from granuloma formation and hepatic injury induced by Schistosoma japonicum eggs, as manifested by reduced body weight loss and attenuated hepatomegaly along with preserved liver function. Notably, S. japonicum infection induced high levels of hepatic Cx3cr1 expression, which was predominantly expressed by infiltrating macrophages. Loss of Cx3cr1 rendered macrophages preferentially towards M2 polarization, which then led to a characteristic switch of the host immune defense from a conventional Th1 to a typical Th2 response during acute schistosomiasis. This immune switch caused by Cx3cr1 deficiency was probably associated with enhanced STAT6/PPAR-γ signaling and increased expression of indoleamine 2,3-dioxygenase (IDO), an enzyme that promotes M2 polarization of macrophages. Taken together, our data provide evidence suggesting that CX3CR1 could be a viable therapeutic target for treatment of acute schistosomiasis. © 2015. Published by The Company of Biologists Ltd.
Profiling Nonrecipients of Mass Drug Administration for Schistosomiasis and Hookworm Infections: A Comprehensive Analysis of Praziquantel and Albendazole Coverage in Community-Directed Treatment in Uganda
Chami, G.; Kontoleon, Andreas A.; Bulte, E.H.; Fenwick, Alan
Background. Repeated mass drug administration (MDA) with preventive chemotherapies is the mainstay of morbidity control for schistosomiasis and soil-transmitted helminths, yet the World Health Organization recently reported that less than one-third of individuals who required preventive
David Alexander Phillips
Full Text Available BACKGROUND Despite public health efforts to reduce the global burden of leprosy, gaps remain in the knowledge surrounding transmission of infection. Helminth co-infections have been associated with a shift towards the lepromatous end of the disease spectrum, potentially increasing transmission in co-endemic areas. OBJECTIVES Using this biologically plausible association, we conducted a geographic information systems (GIS study to investigate the spatial associations of schistosomiasis and leprosy in an endemic area of Minas Gerais (MG, Brazil. METHODS Data on new cases of Mycobacterium leprae and Schistosoma mansoni infections from 2007-2014 were retrieved from the Brazilian national notifiable diseases information system for seven municipalities in and surrounding Vespasiano, MG. A total of 139 cases of leprosy and 200 cases of schistosomiasis were mapped to a municipality level. For one municipality, cases were mapped to a neighborhood level and a stratified analysis was conducted to identify spatial associations. FINDINGS A relative risk of 6.80 [95% confidence interval (CI 1.46 - 31.64] of leprosy was found in neighborhoods with schistosomiasis. Incidence rates of leprosy increased with corresponding incidence rates of schistosomiasis, and the temporal trends of both infections were similar. CONCLUSIONS The associations found in this project support the hypothesis that helminth infections may influence the transmission of leprosy in co-endemic areas.
Full Text Available Rashad Abdul-Ghani1, Naguiba Loutfy2, Manal Sheta3, Azza Hassan21Department of Medical Parasitology, Faculty of Medicine and Health Sciences, Sana’a University, Sana’a, Yemen; 2Tropical Health Department, High Institute of Public Health, 3Department of Pathology, Medical Research Institute, Alexandria University, Alexandria, EgyptAbstract: There is a new trend of “back to nature” in searching for antischistosomal drugs, particularly after the concerns raised about the possible emergence of schistosome isolates resistant/tolerant to praziquantel as well as for their relative safety and fewer side effects. Many plant derivatives have been investigated for efficacy against the Egyptian strain of Schistosoma mansoni, but much attention has been paid to myrrh extract, which is a purified sap obtained from Commiphora molmol. This extract has been produced and marketed in Egypt as a pharmaceutical preparation, but with a great discrepancy in its antischistosomal activity in both experimental and clinical studies. Most previous experimental studies used myrrh in the dosing protocol of 500 mg/kg/day for five days. In the present study, we investigated the therapeutic efficacy of three low-dose myrrh protocols against experimental schistosomiasis mansoni. All these protocols showed no significant efficacy in reducing parasite burdens and tissue egg loads or in changing oogram patterns. Nevertheless, there was an amelioration of hepatic lesions, with reductions in mean counts of hepatic granulomas as well as marked healing of these granulomas.Keywords: Schistosoma mansoni, schistosomiasis mansoni, myrrh, Commiphora molmol, antischistosomal chemotherapy
Full Text Available 90% of the worldwide schistosomiasis burden falls on sub-Saharan Africa. Control efforts are often based on infrequent, small-scale health surveys, which are expensive and logistically difficult to conduct. Use of satellite imagery to predictively model infectious disease transmission has great potential for public health applications. Transmission of schistosomiasis requires specific environmental conditions to sustain freshwater snails, however has unknown seasonality, and is difficult to study due to a long lag between infection and clinical symptoms. To overcome this, we employed a comprehensive 8-year time-series built from remote sensing feeds. The purely environmental predictor variables: accumulated precipitation, land surface temperature, vegetative growth indices, and climate zones created from a novel climate regionalization technique, were regressed against 8 years of national surveillance data in Ghana. All data were aggregated temporally into monthly observations, and spatially at the level of administrative districts. The result of an initial mixed effects model had 41% explained variance overall. Stratification by climate zone brought the R2 as high as 50% for major zones and as high as 59% for minor zones. This can lead to a predictive risk model used to develop a decision support framework to design treatment schemes and direct scarce resources to areas with the highest risk of infection. This framework can be applied to diseases sensitive to climate or to locations where remote sensing would be better suited than health surveys.
Malone, John B; Yang, Guo-Jing; Leonardo, Lydia; Zhou, Xiao-Nong
This review focuses on implementing a geospatial health infrastructure for control of schistosomiasis and other helminthic infections in Southeast Asia, with special focus on the People's Republic of China and the Philippines, using a model working group approach. Health workers have lagged in utilization of geospatial analysis and widely available, low-cost spatial data resources for epidemiological modelling and control programme management. The critical limitation on development of useful health applications to date has not been the availability of geospatial data and methods. Rather, the key barriers have been the speed of adoption of geospatial analysis tools by health scientists and the quality of geographic information system (GIS)-friendly medical databases. Regional GIS applications on Asian schistosomiasis are reviewed to illustrate recent geospatial health analysis applications. A model programme is presented for implementation of training programmes and establishment of regional working groups to facilitate development and use of geospatial health infrastructure resources by health workers in Southeast Asia. Copyright 2010 Elsevier Ltd. All rights reserved.
Abdeen, Sherif H
Anti-idiotypes (anti-Ids) have a potential role in the immune modulation of various diseases. To study the correlation of anti-Ids with schistosomiasis mansoni morbidity, ELISA using polyclonal idiotypes (Ids) was used to determine the presence of anti-Ids in sera of 69 patients susceptible and resistant to reinfection. Ids were purified against Soluble Worm Antigen (SWAP) from sera of New Zealand white rabbits immunized with SWAP. The results showed that anti-Ids were detected in 15 (40.5%) of susceptible and 21 (65.6%) of resistant patients. Correlation of intensity of infection with age revealed an inverse relationship in patients positive for anti-Ids (regression coefficient beta = -0.47, p Ids (beta = 0.67, p Ids and the lack of schistosome-related symptoms (chi2 = 3.6, p Ids revealed that those negative for anti-Ids were more vulnerable to develop symptoms (3.7 times) and hepatomegaly (8.1 times). In conclusion, the study further confirms the role of Id/anti-Id regulatory network as an important participant in the assortment of an improved clinical outcome of schistosomiasis. This may help to formulate a better understanding of the mechanisms of protective immunity in humans and provide perspective for the development of a future vaccine.
Full Text Available Schistosomiasis is one of the major public health problems in the People’s Republic of China (and elsewhere, seriously threatening health as well as social and economic development. An integrated control strategy, emphasising transmission control but also aimed at reducing greenhouse gases, was carried out in Jiangling county, Hubei province from 2007 to 2009. Three villages were chosen for a pilot study involving removal of cattle from neighbouring, snail-infested grasslands, improving sanitation and construction of units for household biogas production in addition to routine control measures. Both prevalence and intensity of infection in the snails in the neighbourhood were greatly reduced after two years of implementation, while the prevalence of schistosomiasis in humans in the three villages had been reduced by 29%, 34% and 24%, respectively. The removal of cattle and construction of biogas production units had an additional positive effect in that the annual, average emission of greenhouse gases such as methane (CH4 and carbon dioxide (CO2 were reduced by an estimated 7.8 and 80.2 tons, respectively.
Full Text Available Two new locations in Spain of Bulinus truncatus (Audouin, 1827 (Gastropoda, Planorbidae, intermediate host of urinary Schistosomiasis Two new populations of the planorbid snail species Bulinus truncatus were found in Spain in 2014. The first consisted of shells only, found in the lagoon of Villena (province of Alicante, which had dried up at the beginning of the 19th century. This finding is of important biogeographic interest because it links the presence of this species in northern Catalonia with its detection in southern Andalucia as this species had not been found previously in the regions of Murcia or Valencia. The second population was found in El Ejido (province of Almeria, and thousands of living specimens were found here. This allowed a complete shell characterisation and molecular assessment by means of sequencing the cox1 gene of the mitochondrial DNA genome, which showed 100% homology with sequences of other populations of the same snail species available in the GenBank. The finding of B. truncatus in Almeria is of additional value given the applied importance of this planorbid species as a vector of urinary Schistosomiasis, thus representing a risk of introduction and autochthonous transmission of the disease in Spain, as has occurred in other southern European countries in the past and recently.
Wrable, M.; Liss, A.; Kulinkina, A.; Koch, M.; Biritwum, N. K.; Ofosu, A.; Kosinski, K. C.; Gute, D. M.; Naumova, E. N.
90% of the worldwide schistosomiasis burden falls on sub-Saharan Africa. Control efforts are often based on infrequent, small-scale health surveys, which are expensive and logistically difficult to conduct. Use of satellite imagery to predictively model infectious disease transmission has great potential for public health applications. Transmission of schistosomiasis requires specific environmental conditions to sustain freshwater snails, however has unknown seasonality, and is difficult to study due to a long lag between infection and clinical symptoms. To overcome this, we employed a comprehensive 8-year time-series built from remote sensing feeds. The purely environmental predictor variables: accumulated precipitation, land surface temperature, vegetative growth indices, and climate zones created from a novel climate regionalization technique, were regressed against 8 years of national surveillance data in Ghana. All data were aggregated temporally into monthly observations, and spatially at the level of administrative districts. The result of an initial mixed effects model had 41% explained variance overall. Stratification by climate zone brought the R2 as high as 50% for major zones and as high as 59% for minor zones. This can lead to a predictive risk model used to develop a decision support framework to design treatment schemes and direct scarce resources to areas with the highest risk of infection. This framework can be applied to diseases sensitive to climate or to locations where remote sensing would be better suited than health surveys.
Leonardo, Lydia; Rivera, Pilarita; Saniel, Ofelia; Villacorte, Elena; Lebanan, May Antonnette; Crisostomo, Bobby; Hernandez, Leda; Baquilod, Mario; Erce, Edgardo; Martinez, Ruth; Velayudhan, Raman
For the first time in the country, a national baseline prevalence survey using a well-defined sampling design such as a stratified two-step systematic cluster sampling was conducted in 2005 to 2008. The purpose of the survey was to stratify the provinces according to prevalence of schistosomiasis such as high, moderate, and low prevalence which in turn would be used as basis for the intervention program to be implemented. The national survey was divided into four phases. Results of the first two phases conducted in Mindanao and the Visayas were published in 2008. Data from the last two phases showed three provinces with prevalence rates higher than endemic provinces surveyed in the first two phases thus changing the overall ranking of endemic provinces at the national level. Age and sex distribution of schistosomiasis remained the same in Luzon and Maguindanao. Soil-transmitted and food-borne helminthes were also recorded in these surveys. This paper deals with the results of the last 2 phases done in Luzon and Maguindanao and integrates all four phases in the discussion.
Full Text Available For the first time in the country, a national baseline prevalence survey using a well-defined sampling design such as a stratified two-step systematic cluster sampling was conducted in 2005 to 2008. The purpose of the survey was to stratify the provinces according to prevalence of schistosomiasis such as high, moderate, and low prevalence which in turn would be used as basis for the intervention program to be implemented. The national survey was divided into four phases. Results of the first two phases conducted in Mindanao and the Visayas were published in 2008. Data from the last two phases showed three provinces with prevalence rates higher than endemic provinces surveyed in the first two phases thus changing the overall ranking of endemic provinces at the national level. Age and sex distribution of schistosomiasis remained the same in Luzon and Maguindanao. Soil-transmitted and food-borne helminthes were also recorded in these surveys. This paper deals with the results of the last 2 phases done in Luzon and Maguindanao and integrates all four phases in the discussion.
Tchuem Tchuenté, Louis-Albert; Momo, Sabine C; Stothard, J Russell; Rollinson, David
The regular administration of the anthelminthic drug praziquantel (PZQ) to school-aged children (and other high-risk groups) is the cornerstone of schistosomiasis control. Whilst the performance of PZQ against single schistosome species infections is well-known, performance against mixed species infections is less so, as are patterns of re-infection following treatment. To address this, a study using a double treatment with PZQ, administered at 40 mg/kg spaced by 3 weeks, took place in two mixed intestinal-urogenital schistosomiasis foci in northern Cameroon (Bessoum and Ouro-Doukoudje) and in one single intestinal schistosomiasis infection focus (Makenene). A total of just under 1000 children were examined and the Schistosoma-infected children were re-examined at several parasitological follow-ups over a 1-year period posttreatment. Overall cure rates against Schistosoma spp. in the three settings were good, 83.3% (95% confidence interval (CI)=77.9-87.7%) in Bessoum, 89.0% (95% CI=79.1-94.6%) in Ouro Doukoudje, and 95.3% (95% CI=89.5-98.0%) in Makenene. Interestingly, no case of mixed schistosome infection was found after treatment. Cure rates for S. mansoni varied from 99.5% to 100%, while that for S. haematobium were considerably lower, varying from 82.7% to 88.0%. Across transmission settings, patterns of re-infection for each schistosome species were different such that generalizations across foci were difficult. For example, at the 6-month follow-up, re-infection rates were higher for S. haematobium than for S. mansoni with re-infection rates for S. haematobium varying from 9.5% to 66.7%, while for S. mansoni, lower rates were observed, ranging between nil and 24.5%. At the 12-month follow-up, re-infection rates varied from 9.1% to 66.7% for S. haematobium and from nil to 27.6% for S. mansoni. Alongside these parasitological studies, concurrent malacological surveys took place to monitor the presence of intermediate host snails of schistosomiasis. In the two
Poggensee, G; Krantz, I; Kiwelu, I; Feldmeier, H
The screening of women of childbearing age for haematuria, leukocyturia and proteinuria to detect urinary schistosomiasis can be confounded by several factors such as menstruation, pregnancy and genitourinary infections. We therefore undertook a study in an area endemic for Schistosoma haematobium in the United Republic of Tanzania to carry out the following: assess the sensitivity, specificity and predictive values--in women of childbearing age--of indirect indicators of urinary schistosomiasis, as measured by urine reagent strip readings; assess the predictive values of self-reported symptoms; and finally to estimate the morbidity attributable to S. haematobium. A total of 303 women (128 and 175, respectively, living in high- and low-risk sites) participated in the study. Haematuria was more frequent among women excreting S. haematobium eggs than among those who did not (65% versus 32%). The predictive potential of all indirect disease markers was poor in the highly endemic site, while in the sites with low endemicity the negative predictive values were high. Among infected women, 54% of haematuria could be attributed to S. haematobium, but for patients with more than 10 eggs/10 ml the attributable fraction rose to 70%. Symptoms of "bloody urine" and "pain while urinating" were recalled significantly more often by women living in the highly endemic site. On a population level, one-third of the self-reported cases with bloody urine could be attributed to urinary schistosomiasis. Screening of women of childbearing age for urinary schistosomiasis using urine reagent strips can be biased in two directions. The prevalence of S. haematobium will be overestimated if other causes of haematuria, such as reproductive tract infections, are highly endemic. On the other hand, women with light or very light infections will be missed and will not be treated. This is of concern because genital schistosomiasis, a possible risk factor for the transmission of HIV, occurs among
Eridan M. Coutinho
Full Text Available Body, liver and spleen weights; histopathology of the liver, spleen and intestines; hepatic and serum soluble proteins changes were the parameters studied in undernourished Swiss albino mice experimentally infected with S. mansoni. Non-infected deficient animab had lower liver/body weight and spleen/body weight ratios as compared to the controls (22.60% casein group. Infected mice showed higher values regardless the type of diet. Undernourished infected subgroup showed a persistent exudative periovular reaction in the liver. Soluble hepatic proteins content and serum protein fractions appeared to be lower in the deficient infected mice. A significant difference was detected in the gammaglobulin fraction between infected and non-infected animals fed the control diet with higher values for the former. Our data suggest that the effects of malnutrition, per se, are sometimes more detrimental to the host than those due to Manson 's schistosomiasis.No presente estudo os pesos corporal, hepático e esplénico; a morfologia patológica do fígado, baço e intestinos; e as modificações das proteínas solúveis hepáticas e séricas, foram os parâmetros investigados em camundongos albinos Suíços desnutridos e infectados com S. mansoni. Os animais desnutridos não infectados apresentaram relações fígado/peso corporal e baço! peso corporal com valores menores do que os animais controles (grupo caseina a 22,60%. Camundongos infectados mostraram esses índices mais elevados, independentemente do tipo de dieta. O subgrupo de camundongos desnutridos infectados apresentou, no fígado, reação periovular exsudativa persistente. O conteúdo de proteínas solúveis no fígado e no soro também mostrou-se reduzido nos camundongos infectados desnutridos. Diferença significativa foi detectada quanto às gamaglobulinas, comparando-se animais infectados com não infectados alimentados com a dieta controle II, valores mais altos ocorrendo no grupo dos
Mas-Coma, Santiago; Valero, Maria Adela; Bargues, Maria Dolores
The capacity of climatic conditions to modulate the extent and intensity of parasitism is well known since long ago. Concerning helminths, among the numerous environmental modifications giving rise to changes in infections, climate variables appear as those showing a greater influence, so that climate change may be expected to have an important impact on the diseases they cause. However, the confirmation of the impact of climate change on helminthiases has been reached very recently. Only shortly before, helminthiases were still noted as infectious diseases scarcely affected by climate change, when compared to diseases caused by microorganisms in general (viruses, bacteriae, protozoans). The aim of the present paper is to review the impact of climate change on helminthiases transmitted by snails, invertebrates which are pronouncedly affected by meteorological factors, by focusing on trematodiases. First, the knowledge on the effects of climate change on trematodiases in general is reviewed, including aspects such as influence of temperature on cercarial output, cercarial production variability in trematode species, influences of magnitude of cercarial production and snail host size, cercarial quality, duration of cercarial production increase and host mortality, influence of latitude, and global-warming-induced impact of trematodes. Secondly, important zoonotic diseases such as fascioliasis, schistosomiasis and cercarial dermatitis are analysed from the point of view of their relationships with meteorological factors. Emphasis is given to data which indicate that climate change influences the characteristics of these trematodiases in concrete areas where these diseases are emerging in recent years. The present review shows that trematodes, similarly as other helminths presenting larval stages living freely in the environment and/or larval stages parasitic in invertebrates easily affected by climate change as arthropods and molluscs as intermediate hosts, may be
correlation between ECP and infection intensity (Spearman's r=0.73, P<0.001.Conclusion: This study showed that ECP levels are positively associated with infection intensity by egg count in Schistosomiasis infections, even after multivariate adjustment.Keywords: infection intensity, risk factors, urine filtration, Kato-Katz
Full Text Available Rashad Abdul-Ghani1, Naguiba Loutfy2, Manal Sheta3, Azza Hassan21Department of Medical Parasitology, Faculty of Medicine and Health Sciences, Sana’a University, Sana’a, Yemen; 2Tropical Health Department, High Institute of Public Health, 3Department of Pathology, Medical Research Institute, Alexandria University, Alexandria, EgyptPurpose: Combination chemotherapy of Schistosoma mansoni has been studied previously, with praziquantel being the basis of combination. Artemether and myrrh are compounds of a natural origin that have been investigated experimentally and clinically against schistosomiasis. Artemether is used as an antimalarial drug, and has been used as a chemoprophylactic drug against Schistosoma japonica in China whereas myrrh extract is manufactured and prescribed as an antischistosomal drug in Egypt. The present study investigated the experimental efficacy of combining artemether and myrrh using three different protocols in mice infected with the Egyptian strain of S. mansoni.Methods: Experiments were performed on 40 eight-week-old female Swiss albino mice divided into three experimental groups and one control group. Assessment of efficacy was based on a suite of parasitologic and histopathologic parameters. Parasitologic parameters included reductions in total and female worm burdens, reductions in hepatic and intestinal wall tissue egg loads, and alterations in oogram patterns in the experimental groups compared to the infected untreated control. Histopathologic parameters comprised microscopic examination of liver sections stained with hematoxylin and eosin to study the reductions in the mean counts and diameters of hepatic granulomas as well as their healing ratios compared to the control.Results: Reductions of 43.9%–58.2% in total worm burdens and 42.4%–63.7% in female worm burdens were induced. Meanwhile, significant reductions of 63.1%–77.8% in eggs per gram of small intestinal tissue and of 56.5%–66.3% in eggs
Luiz Augusto Magalhães
Full Text Available Realizou-se estudo sobre o desenvolvimento da esquistossomose mansônica em camundongos submetidos à dieta hipoprotéica. Foram constituídos 4 grupos de Mus musculus "Swiss" da seguinte forma: 1 não infectados, normoprotéicos; 2 infectados, normoprotéicos; 3 não infectados, hipoprotéicos e 4 infectados, hipoprotéicos. Os animais foram sacrificados com 60 dias de infecção, aos 90 dias de idade. Verificou-se que os esquistossomos sofreram os efeitos da subnutrição do hospedeiro, principalmente os vermes machos, que além de terem seu desenvolvimento prejudicado, tiveram seu número reduzido aproximadamente pela metade. O número de granulomas foi menor nos roedores subnutridos e o tamanho da lesão foi reduzido. Houve acentuada leucopenia nos animais submetidos à dieta hipoprotéica, principalmente nos infectados subnutridos. A linfopenia e a eosinopenia acentuadas sugeriram que o sistema imunológico do hospedeiro foi afetado pela subnutrição. A taxa de mortalidade foi muito mais elevada nos animais infectados submetidos à dieta hipoprotéica. Concluiu-se que os camundongos subnutridos resistiram menos à infecção esquistossomótica apesar de terem apresentado menor número de lesões granulomatosas.Mansoni schistosomiasis was studied in mice fed on a low protein diet. Four groups of the Swiss breed Mus musculus were used in an experiment with two factors, each with two levels: 1-non-infected, normal diet; 2 - infected, normal diet ; 3 - non-infected, low protein diet; 4 - infected, low protein diet. The mice were killed for observation at age 90 days, after 60 days of infection, for those infected. It was found that the worms suffered the effects of malnutrition, mainly males, whose population count was cut by half, in addition to poor individual growth. The hepatic granuloma count was found to be smaller in the undernourished group; while the corresponding lesions were also generally smaller. There was a marked leukopenia in
Pillay, Pavitra; van Lieshout, Lisette; Taylor, Myra; Sebitloane, Motshedisi; Zulu, Siphosenkosi Gift; Kleppa, Elisabeth; Roald, Borghild; Kjetland, Eyrun Floerecke
Background: Female genital schistosomiasis (FGS) is a tissue reaction to lodged ova of Schistosoma haematobium in the genital mucosa. Lesions can make the mucosa friable and prone to bleeding and discharge. Women with FGS may have an increased risk of HIV acquisition, and FGS may act as a cofactor in the development of cervical cancer. Objectives: To explore cytology as a method for diagnosing FGS and to discuss the diagnostic challenges in low-resource rural areas. The correlation between FGS and squamous cell atypia (SCA) is also explored and discussed. Cytology results are compared to Schistosoma polymerase chain reaction (PCR) in vaginal lavage and urine and in urine microscopy. Materials and Methods: In a clinical study, 394 women aged between 16 and 23 years from rural high schools in KwaZulu-Natal, South Africa, underwent structured interviews and the following laboratory tests: Cytology Papanicolaou (Pap) smears for S. haematobium ova and cervical SCA, real-time PCR for Schistosoma-specific DNA in vaginal lavage and urine samples, and urine microscopy for the presence of S. haematobium ova. Results: In Pap smears, S. haematobium ova were detected in 8/394 (2.0%). SCA was found in 107/394 (27.1%), seven of these had high-grade squamous intraepithelial lesion (HSIL). Schistosoma specific DNA was detected in 38/394 (9.6%) of vaginal lavages and in 91/394 (23.0%) of urines. Ova were found microscopically in 78/394 (19.7%) of urines. Conclusion: Schistosoma PCR on lavage was a better way to diagnose FGS compared to cytology. There was a significant association between S. haematobium ova in Pap smears and the other diagnostic methods. In low-resource Schistosoma-endemic areas, it is important that cytology screeners are aware of diagnostic challenges in the identification of schistosomiasis in addition to the cytological diagnosis of SCA. Importantly, in this study, three of eight urines were negative but showed Schistosoma ova in their Pap smear, and one of them
Full Text Available BACKGROUND: Schistosomiasis is a water-based disease that is believed to affect over 200 million people with an estimated 97% of the infections concentrated in Africa. However, these statistics are largely based on population re-adjusted data originally published by Utroska and colleagues more than 20 years ago. Hence, these estimates are outdated due to large-scale preventive chemotherapy programs, improved sanitation, water resources development and management, among other reasons. For planning, coordination, and evaluation of control activities, it is essential to possess reliable schistosomiasis prevalence maps. METHODOLOGY: We analyzed survey data compiled on a newly established open-access global neglected tropical diseases database (i to create smooth empirical prevalence maps for Schistosoma mansoni and S. haematobium for individuals aged ≤ 20 years in West Africa, including Cameroon, and (ii to derive country-specific prevalence estimates. We used Bayesian geostatistical models based on environmental predictors to take into account potential clustering due to common spatially structured exposures. Prediction at unobserved locations was facilitated by joint kriging. PRINCIPAL FINDINGS: Our models revealed that 50.8 million individuals aged ≤ 20 years in West Africa are infected with either S. mansoni, or S. haematobium, or both species concurrently. The country prevalence estimates ranged between 0.5% (The Gambia and 37.1% (Liberia for S. mansoni, and between 17.6% (The Gambia and 51.6% (Sierra Leone for S. haematobium. We observed that the combined prevalence for both schistosome species is two-fold lower in Gambia than previously reported, while we found an almost two-fold higher estimate for Liberia (58.3% than reported before (30.0%. Our predictions are likely to overestimate overall country prevalence, since modeling was based on children and adolescents up to the age of 20 years who are at highest risk of infection. CONCLUSION
Schur, Nadine; Hürlimann, Eveline; Garba, Amadou; Traoré, Mamadou S; Ndir, Omar; Ratard, Raoult C; Tchuem Tchuenté, Louis-Albert; Kristensen, Thomas K; Utzinger, Jürg; Vounatsou, Penelope
Schistosomiasis is a water-based disease that is believed to affect over 200 million people with an estimated 97% of the infections concentrated in Africa. However, these statistics are largely based on population re-adjusted data originally published by Utroska and colleagues more than 20 years ago. Hence, these estimates are outdated due to large-scale preventive chemotherapy programs, improved sanitation, water resources development and management, among other reasons. For planning, coordination, and evaluation of control activities, it is essential to possess reliable schistosomiasis prevalence maps. We analyzed survey data compiled on a newly established open-access global neglected tropical diseases database (i) to create smooth empirical prevalence maps for Schistosoma mansoni and S. haematobium for individuals aged ≤ 20 years in West Africa, including Cameroon, and (ii) to derive country-specific prevalence estimates. We used Bayesian geostatistical models based on environmental predictors to take into account potential clustering due to common spatially structured exposures. Prediction at unobserved locations was facilitated by joint kriging. Our models revealed that 50.8 million individuals aged ≤ 20 years in West Africa are infected with either S. mansoni, or S. haematobium, or both species concurrently. The country prevalence estimates ranged between 0.5% (The Gambia) and 37.1% (Liberia) for S. mansoni, and between 17.6% (The Gambia) and 51.6% (Sierra Leone) for S. haematobium. We observed that the combined prevalence for both schistosome species is two-fold lower in Gambia than previously reported, while we found an almost two-fold higher estimate for Liberia (58.3%) than reported before (30.0%). Our predictions are likely to overestimate overall country prevalence, since modeling was based on children and adolescents up to the age of 20 years who are at highest risk of infection. We present the first empirical estimates for S. mansoni and S
Balahbib, Abdelaali; Amarir, Fatima; Corstjens, Paul L A M; de Dood, Claudia J; van Dam, Govert J; Hajli, Amina; Belhaddad, Meryem; El Mansouri, Bouchra; Sadak, Abderrahim; Rhajaoui, Mohamed; Adlaoui, El Bachir
After alleged stop of transmission of schistosomiasis and further down the line in post elimination settings, sensitive tools are required to monitor infection status to prevent potential re-emergence. In Rahala, where transmission cycle of Schistosoma haematobium is interrupted since 2004 but where 30% of snails are still infected by S. bovis, potential human S. bovis infection can't be excluded. As methods based on egg-counts do not provide the required sensitivity, antibody or antigen assays are envisaged as the most appropriate tools for this type of monitoring. In this pilot study, the performances of three assays were compared: two commercially available antibody tests (ELISA and haemagglutination format) indicating exposure, and an antigen test (lateral flow strip format) demonstrating active infection. All 37 recruited study participants resided in Rahala (Akka, province Tata, Morocco). Participants had been diagnosed and cured from schistosomiasis in the period between 1983 and 2003. In 2015 these asymptomatic participants provided fresh clinical samples (blood and urine) for analysis with the aforementioned diagnostics tests. No eggs were identified in the urine of the 37 participants. The haemagglutination test indicated 6 antibody positives whereas the ELISA indicated 28 antibody positives, one indecisive and one false positive. ELISA and haemagglutination results matched for 18 individuals, amongst which 5 out of 6 haemagglutination positives. With the antigen test (performed on paired serum and urine samples), serum from two participants (cured 21 and 32 years ago) indicated the presence of low levels of the highly specific Schistosoma circulating anodic antigen (CAA), demonstrating low worm level infections (less than 5 pg/ml corresponding to probably single worm pair). One tested also CAA positive with urine. ELISA indicated the presence of human anti-Schistosoma antibodies in these two CAA positive cases, haemagglutination results were negative
Muhumuza, Simon; Olsen, Annette; Katahoire, Anne
-treatment snack on uptake of mass treatment.Methods and Findings:In a cluster randomized trial carried out in Jinja district, Uganda, 12 primary schools were randomized into two groups; one received education messages for schistosomiasis prevention for two months prior to mass treatment, while the other......, in addition to the education messages, received a pre-treatment snack shortly before mass treatment. Four weeks after mass treatment, uptake of praziquantel was assessed among a random sample of 595 children in the snack schools and 689 children in the non-snack schools as the primary outcome. The occurrence...... of side effects and the prevalence and mean intensity of Schistosoma mansoni infection were determined as the secondary outcomes. Uptake of praziquantel was higher in the snack schools, 93.9% (95% CI 91.7%-95.7%), compared to that in the non-snack schools, 78.7% (95% CI 75.4%-81.7%) (p = 0...
Pezzuto, J M; Swanson, S M; Farnsworth, N R
Extracts of the fruit of Phytolacca dodecandra (endod) demonstrate molluscicidal and other biological activities. Since this plant is indigenous to some countries where schistosomiasis is a common problem, it has been proposed that it may be socioeconomically feasible to employ endod as an aid in the control of this disease through its use to control the snail vector. As an initial step in the safety assessment of this substance, its mutagenic potential was determined utilizing Salmonella typhimurium strain TM677. The seeds and fruit of Phytolacca americana, also molluscicidal, were additionally evaluated for mutagenic potential. Using a variety of conditions, no mutagenic activity could be demonstrated for any of the extracts tested. Thus, subject to the results of future safety assessment, endod remains a viable candidate as a useful molluscicide.
Charles H King
Full Text Available Controversy persists about the optimal approach to drug-based control of schistosomiasis in high-risk communities. In a systematic review of published studies, we examined evidence for incremental benefits from repeated praziquantel dosing, given 2 to 8 weeks after an initial dose, in Schistosoma-endemic areas of Africa.We performed systematic searches of electronic databases PubMed and EMBASE for relevant data using search terms 'schistosomiasis', 'dosing' and 'praziquantel' and hand searches of personal collections and bibliographies of recovered articles. In 10 reports meeting study criteria, improvements in parasitological treatment outcomes after two doses of praziquantel were greater for S. mansoni infection than for S. haematobium infection. Observed cure rates (positive to negative conversion in egg detection assays were, for S. mansoni, 69-91% cure after two doses vs. 42-79% after one dose and, for S. haematobium, 46-99% cure after two doses vs. 37-93% after a single dose. Treatment benefits in terms of reduction in intensity (mean egg count were also different for the two species-for S. mansoni, the 2-dose regimen yielded an weighted average 89% reduction in standardized egg counts compared to a 83% reduction after one dose; for S. haematobium, two doses gave a 93% reduction compared to a 94% reduction with a single dose. Cost-effectiveness analysis was performed based on Markov life path modeling.Although schedules for repeated treatment with praziquantel require greater inputs in terms of direct costs and community participation, there are incremental benefits to this approach at an estimated cost of $153 (S. mansoni-$211 (S. haematobium per additional lifetime QALY gained by double treatment in school-based programs. More rapid reduction of infection-related disease may improve program adherence, and if, as an externality of the program, transmission can be reduced through more effective coverage, significant additional benefits are
Xie, Yuanyuan; Wen, Huiqin; Yan, Ke; Wang, Shushu; Wang, Xuesong; Chen, Jian; Li, Yuanling; Xu, Yuanhong; Zhong, Zhengrong; Shen, Jilong; Chu, Deyong
Recent studies indicated that type II Toxoplasma gondii (Tg) GRA15 II favored the generation of classically activated macrophages (M1), whereas type I/III TgROP16 I/III promoted the polarization of alternatively activated macrophages (M2). A number of studies have demonstrated that M2 cells are involved in the pathogenesis of the liver fibrogenesis caused by Schistosoma japonicum. The purpose of the present study was to explore the inhibitory effect of Toxoplasma-derived TgGRA15 II on mouse hepatic fibrosis with schistosomiasis. The gra15 II and rop16 I/III genes were amplified from strains T. gondii PRU and Chinese 1 Wh3, respectively. Lentiviral vectors containing the gra15 II or rop16 I/III plasmid were constructed and used to infect the RAW264.7 cell line. The polarization of the transfected cells was evaluated, followed by co-culture of the biased macrophages with mouse hepatic stellate JS1 cells. Then, mice were injected with GRA15 II -driven macrophages via the tail vein and infected with S. japonicum cercariae. TgGRA15 II induced a M1-biased response, whereas TgROP16 I/III drove the macrophages to a M2-like phenotype. The in vitro experiments indicated that JS1 cell proliferation and collagen synthesis were decreased following co-culture with TgGRA15 II -activated macrophages. Furthermore, mice inoculated with TgGRA15 II -biased macrophages displayed a notable alleviation of collagen deposition and granuloma formation in their liver tissues. Our results suggest that TgGRA15 II -induced M1 cells may dampen the M2 dominant pathogenesis of hepatic fibrosis and granulomatosis. These results provide insights into the use of parasite-derived immunomodulators as potential anti-fibrosis agents and to re-balance the schistosomiasis-induced immune response.
Silvia Regina Costa Dias
Full Text Available Schistosomiasis is a neglected tropical disease, and after malaria, is the second most important tropical disease in public health. A vaccine that reduces parasitemia is desirable to achieve mass treatment with a low cost. Although potential antigens have been identified and tested in clinical trials, no effective vaccine against schistosomiasis is available. Y-box-binding proteins (YBPs regulate gene expression and participate in a variety of cellular processes, including transcriptional and translational regulation, DNA repair, cellular proliferation, drug resistance and stress responses. The Schistosoma mansoni ortholog of the human YB-1, SMYB1, is expressed in all stages of the parasite life cycle. Although SMYB1 binds to DNA or RNA oligonucleotides, immunohistochemistry assays demonstrated that it is primarily localized in the cytoplasm of parasite cells. In addition, SMYB1 interacts with a protein involved in mRNA processing, suggesting that SMYB1 functions in the turnover, transport and/or stabilization of RNA molecules during post-transcriptional gene regulation. Here we report the potential of SMYB1 as a vaccine candidate. We demonstrate that recombinant SMYB1 stimulates the production of high levels of specific IgG1 antibodies in a mouse model. The observed levels of specific IgG1 and IgG2a antibodies indicate an actual protection against cercariae challenge. Animals immunized with rSMYB1 exhibited a 26% reduction in adult worm burden and a 28% reduction in eggs retained in the liver. Although proteins from the worm tegument are considered optimal targets for vaccine development, this study demonstrates that unexposed cytoplasmic proteins can reduce the load of intestinal worms and the number of eggs retained in the liver.
Dias, Sílvia R C; Boroni, Mariana; Rocha, Elizângela A; Dias, Thomaz L; de Laet Souza, Daniela; Oliveira, Fabrício M S; Bitar, Mainá; Macedo, Andrea M; Machado, Carlos R; Caliari, Marcelo V; Franco, Glória R
Schistosomiasis is a neglected tropical disease, and after malaria, is the second most important tropical disease in public health. A vaccine that reduces parasitemia is desirable to achieve mass treatment with a low cost. Although potential antigens have been identified and tested in clinical trials, no effective vaccine against schistosomiasis is available. Y-box-binding proteins (YBPs) regulate gene expression and participate in a variety of cellular processes, including transcriptional and translational regulation, DNA repair, cellular proliferation, drug resistance, and stress responses. The Schistosoma mansoni ortholog of the human YB-1, SMYB1, is expressed in all stages of the parasite life cycle. Although SMYB1 binds to DNA or RNA oligonucleotides, immunohistochemistry assays demonstrated that it is primarily localized in the cytoplasm of parasite cells. In addition, SMYB1 interacts with a protein involved in mRNA processing, suggesting that SMYB1 functions in the turnover, transport, and/or stabilization of RNA molecules during post-transcriptional gene regulation. Here we report the potential of SMYB1 as a vaccine candidate. We demonstrate that recombinant SMYB1 stimulates the production of high levels of specific IgG1 antibodies in a mouse model. The observed levels of specific IgG1 and IgG2a antibodies indicate an actual protection against cercariae challenge. Animals immunized with rSMYB1 exhibited a 26% reduction in adult worm burden and a 28% reduction in eggs retained in the liver. Although proteins from the worm tegument are considered optimal targets for vaccine development, this study demonstrates that unexposed cytoplasmic proteins can reduce the load of intestinal worms and the number of eggs retained in the liver.