André Capron; Gilles Riveau; Jean-Marie Grzych; Denis Boulanger; Monique Capron; Raymond Pierce
Schistosomiasis is a chronic and debilitating parasitic disease that affects over 200 million people throughout the world and causes about 500,000 deaths annually. Two specific characteristics of schistosome infection are of primordial importance to the development of a vaccine: schistosomes do not multiply within the tissues of their definitive hosts (unlike protozoan parasites) and a partial non-sterilizing immunity can have a marked effect on the incidence of pathology and on disease trans...
Full Text Available Schistosomiasis is a chronic and debilitating parasitic disease that affects over 200 million people throughout the world and causes about 500,000 deaths annually. Two specific characteristics of schistosome infection are of primordial importance to the development of a vaccine: schistosomes do not multiply within the tissues of their definitive hosts (unlike protozoan parasites and a partial non-sterilizing immunity can have a marked effect on the incidence of pathology and on disease transmission. Since viable eggs are the cause of disease pathology, a reduction in worm fecundity whether or not accompanied by a reduction in parasite burden is a sufficient goal for vaccine induced immunity. We originally showed that IgE antibodies played in experimental models a pivotal role for the development of protective immunity. These laboratory findings have been now confirmed in human populations. Following the molecular cloning and expression of a protein 28 kDa protein of Schistosoma mansoni and its identification as a glutathion S-transferase, immunization experiments have been undertaken in several animal species (rats, mice, baboons. Together with a significant reduction in parasite burden, vaccination with Sm28 GST was recently shown to reduce significantly parasite fecundity and egg viability leading to a decrease in liver pathology. Whereas IgE antibodies were shown to be correlated with protection against infection, IgA antibodies have been identified as one of the factors affecting egg laying and viability. In human populations, a close association was found between IgA antibody production to Sm28 GST and the decrease of egg output. The use of appropriate monoclonal antibody probes has allowed the demonstration that the inhibition of parasite fecundity following immunization was related to the inhibition of enzymatic activity of the molecule. Epitope mapping of Sm28 GST has indicated the prominent role of the N and C terminal domains
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.
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
Elizabeth J Carlton
Full Text Available BACKGROUND: Schistosomiasis has reemerged in China, threatening schistosomiasis elimination efforts. Surveillance methods that can identify locations where schistosomiasis has reemerged are needed to prevent the further spread of infections. METHODS AND PRINCIPAL FINDINGS: We tested humans, cows, water buffalo and the intermediate host snail, Oncomelania hupensis, for Schistosoma japonicum infection, assessed snail densities and extracted regional surveillance records in areas where schistosomiasis reemerged in Sichuan province. We then evaluated the ability of surveillance methods to identify villages where human infections were present. Human infections were detected in 35 of the 53 villages surveyed (infection prevalence: 0 to 43%, including 17 of 28 villages with no prior evidence of reemergence. Bovine infections were detected in 23 villages (infection prevalence: 0 to 65% and snail infections in one village. Two common surveillance methods, acute schistosomiasis case reports and surveys for S. japonicum-infected snails, grossly underestimated the number of villages where human infections were present (sensitivity 1% and 3%, respectively. Screening bovines for S. japonicum and surveys for the presence of O. hupensis had modest sensitivity (59% and 69% respectively and specificity (67% and 44%, respectively. Older adults and bovine owners were at elevated risk of infection. Testing only these high-risk human populations yielded sensitivities of 77% and 71%, respectively. CONCLUSIONS: Human and bovine schistosomiasis were widespread in regions where schistosomiasis had reemerged but acute schistosomiasis and S. japonicum-infected snails were rare and, therefore, poor surveillance targets. Until more efficient, sensitive surveillance strategies are developed, direct, targeted parasitological testing of high-risk human populations should be considered to monitor for schistosomiasis reemergence.
Full Text Available Background: Schistosomal infestation of the central nervous system is a rare cause of cord compression, although a predominant one in endemic areas. Case Description: A 38-year-old male, native of Ivory Coast, with a history of 1 month of progressive paraparesis, neurogenic bladder, diminished deep tendon reflexes of the lower limbs, and sensory level. The magnetic resonance imaging (MRI showed a medullary lesion at D4-D5 level, suggestive of an intramedullary tumor. Laminotomy of D3 to D5 and excision of a grayish white lesion according to a preliminary histopathologic review suggestive of a high grade glioma. Definitive histopathology review established the diagnosis of medullary schistosomiasis. Conclusion: Schistosomal myeloradiculopathy should be considered in patients presenting with cord compression or features of transverse myelitis, especially in patients from endemic areas or low social economic settlements.
Salwa Dawaki; Al-Mekhlafi, Hesham M.; Init Ithoi; Jamaiah Ibrahim; Abdulsalam, Awatif M.; Abdulhamid Ahmed; Hany Sady; Nasr, Nabil A.; Atroosh, Wahib M
Background Schistosomiasis is one of the most common neglected tropical diseases, especially in the developing countries in Africa, Asia and South America, with Nigeria having the greatest number of cases of schistosomiasis worldwide. This community-based study aims to evaluate the knowledge, attitude and practices (KAP) regarding schistosomiasis among rural Hausa communities in Kano State, Nigeria. Methods A cross-sectional study was carried out among 551 participants from Hausa communities ...
Schöpke, K; Gomez, A; Dunbar, K A; Swalve, H H; Döpfer, D
Bovine digital dermatitis (DD) is an increasing claw health problem in all cattle production systems worldwide. The objective of this study was to evaluate the use of an improved scoring of the clinical status for DD via M-scores accounting for the dynamics of the disease; that is, the transitions from one stage to another. The newly defined traits were then subjected to a genetic analysis to determine the genetic background for susceptibility to DD. Data consisted of 6,444 clinical observations from 729 Holstein heifers in a commercial dairy herd, collected applying the M-score system. The M-score system is a classification scheme for stages of DD that allows a macroscopic scoring based on clinical inspections of the bovine foot, thus it describes the stages of lesion development. The M-scores were used to define new DD trait definitions with different complexities. Linear mixed models and logistic models were used to identify fixed environmental effects and to estimate variance components. In total, 68% of all observations showed no DD status, whereas 11% were scored as infectious for and affected by DD, and 21% of all observations exhibited an affected but noninfectious status. For all traits, the probability of occurrence and clinical status were associated with age at observation and period of observation. Risk of becoming infected increased with age, and month of observation significantly affected all traits. Identification of the optimal month concerning DD herd status was consistent for all trait definitions; the last month of the trial was identified. In contrast, months exhibiting the highest least squares means of transformed scores differed depending on trait definition. In this respect, traits that can distinguish between healthy, infectious, and noninfectious stages of DD can account for the infectious potential of the herd and can serve as an alert tool. Estimates of heritabilities of traits studied ranged between 0.19 (±0.11) and 0.52 (±0
Kramer, Christine V; Zhang, Fan; Sinclair, David; Olliaro, Piero L
Background Urinary schistosomiasis is caused by an intravascular infection with parasitic Schistosoma haematobium worms. The adult worms typically migrate to the venous plexus of the human bladder and excrete eggs which the infected person passes in their urine. Chronic infection can cause substantial morbidity and long-term complications as the eggs become trapped in human tissues causing inflammation and fibrosis. We summarised evidence of drugs active against the infection. This is new edi...
Nicola Mortati Neto
Full Text Available Schistosomiasis or bilharziasis is a disease caused by Schistosoma. When infecting men the most common parasites are Schistosoma mansoni, Schistosoma japonicum and Schistosoma haematobium. The Schistosoma mansoni is the only endemic parasite in Brazil. We present a case of testicular schistosomiasis simulating malignancy. The case was treated successfully by excisional biopsy and praziquantel therapy. A review of the literature is discussed.
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...
Leite, Luiz Arthur Calheiros; Pimenta Filho, Adenor Almeida; Ferreira, Rita de Cássia dos Santos; da Fonseca, Caíque Silveira Martins; dos Santos, Bianka Santana; Montenegro, Silvia Maria Lucena; LOPES Edmundo Pessoa de Almeida; Domingues, Ana Lúcia Coutinho; Owen, James Stuart; Lima, Vera Lucia de Menezes
Background 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 live...
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
Background 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. Methods 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 usin...
Walz, Yvonne; Wegmann, Martin; Dech, Stefan; Raso, Giovanna; Utzinger, Jürg
Background Schistosomiasis is a water-based disease that affects an estimated 250 million people, mainly in sub-Saharan Africa. The transmission of schistosomiasis is spatially and temporally restricted to freshwater bodies that contain schistosome cercariae released from specific snails that act as intermediate hosts. Our objective was to assess the contribution of remote sensing applications and to identify remaining challenges in its optimal application for schistosomiasis risk profiling i...
Ørnbjerg, Niels; Simonsen, P. E.; Furu, Peter
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 t...... 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....
Full Text Available Abstract Background Schistosoma japonicum is a major public health concern in the Peoples' Republic of China (PRC, with over one million 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 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 both above and below the TGD across five provinces (Hunan, Jiangxi, Hubei, Anhui and Sichuan to determine whether there was any impact of the TGD on schistosomiasis transmission during its construction. Here we present the results from a schistosomiasis-endemic village located above the dam in Sichuan Province. Results Baseline results showed a human S. japonicum prevalence of 42.0% (95% CI: 36.6-47.5. At follow-up, results showed that the incidence of S. japonicum infection in the selected human cohort in Shian decreased by three quarters from 46% in 2003 to 11.3% in 2006. A significant (P S. japonicum infection in bovines declined from 11.8% in the first year to zero in the final year of follow-up. Conclusions The substantial decrease in human (75% and bovine (100% incidence observed in Shian village can probably be attributed to the annual human and bovine PZQ treatment of positives; as seen in drug (PZQ intervention studies in other parts of PRC. 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 the construction of the TGD had virtually no impact on schistosomiasis transmission in Shian village over the period of study. Furthermore, contrary to previous reports from
Dawaki, Salwa; Al-Mekhlafi, Hesham M.; Ithoi, Init; Ibrahim, Jamaiah; Abdulsalam, Awatif M.; Ahmed, Abdulhamid; Sady, Hany; Nasr, Nabil A.; Atroosh, Wahib M.
Background Schistosomiasis is one of the most common neglected tropical diseases, especially in the developing countries in Africa, Asia and South America, with Nigeria having the greatest number of cases of schistosomiasis worldwide. This community-based study aims to evaluate the knowledge, attitude and practices (KAP) regarding schistosomiasis among rural Hausa communities in Kano State, Nigeria. Methods A cross-sectional study was carried out among 551 participants from Hausa communities in five local government areas in Kano State, North Central Nigeria. Demographic, socioeconomic and environmental information as well as KAP data were collected using a pre-tested questionnaire. Moreover, faecal and urine samples were collected and examined for the presence of Schistosoma mansoni and S. haematobium eggs respectively. Results The overall prevalence of schistosomiasis was 17.8%, with 8.9% and 8.3% infected with S. mansoni and S. haematobium respectively, and 0.5% had co-infection of both species. Moreover, 74.5% of the participants had prior knowledge about schistosomiasis with 67.0% of them how it is transmitted and 63.8% having no idea about the preventive measures. Three-quarters of the respondents considered schistosomiasis a serious disease while their practices to prevent infections were still inadequate, with only 34.7% of them seeking treatment from clinics/hospitals. Significant associations between the KAP and age, gender, education and employment status were reported. Multiple logistic regression analysis revealed that age, gender, history of infection and educational level of the respondents were the most important factors significantly associated with the KAP on schistosomiasis among this population. Conclusions Schistosomiasis is still prevalent among Hausa communities in Nigeria and participants’ knowledge about the disease was poor. Mass drug administration, community mobilization and health education regarding the cause, transmission and
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.
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
Darren J Gray
Full Text Available BACKGROUND: 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. METHODOLOGY/PRINCIPAL FINDINGS: 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. CONCLUSIONS/SIGNIFICANCE: 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.
Barros, Cláudia Renata Castro do Rêgo; Maia, Daniela Cristina Caetano; dos Santos, Josemir Belo; Medeiros, Camila Carolina Queiroz; de Araújo, Jessica Guido
Cutaneous schistosomiasis is a rare clinical manifestation of schistosomiasis, an infectious and parasitic disease, caused in Brazil by the trematode Schistosoma mansoni. The lesions are due to the deposition of eggs or, rarely, adult worms, usually involving the genital and groin areas. Extra-genital lesions occur mainly on the torso as papules of zosteriform appearance. The case of a patient with ectopic cutaneous schistosomiasis is reported in this article, due to the rarity of its occurre...
Utzinger, Jürg; Brattig, Norbert W.; Kristensen, Thomas K.
, the current piece provides an umbrella for the 25-article collection, including current gaps and remaining research needs. Finally, post-CONTRAST initiatives are discussed and a speculative viewpoint is given on how schistosomiasis control/elimination will have evolved over the next several years....... 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...... and discuss its overarching goal, the interrelated objectives, establishment and running of a research node network across Africa, partnership configuration and modus operandi of the project. A collection of 25 articles is presented that are grouped into five main themes: molecular, biological, spatial...
Luiz C. de S. Dias; Oswaldo Marçal Jr.; GLASSER Carmem M.
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 prog...
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
Sokolow, Susanne H.; Wood, Chelsea L.; Jones, Isabel J.; Lopez, Melina; Lafferty, Kevin D.; Kuris, Armand M.; Rickards, Chloe; De Leo, Giulio A.
Background Despite control efforts, human schistosomiasis remains prevalent throughout Africa, Asia, and South America. The global schistosomiasis burden has changed little since the new anthelmintic drug, praziquantel, promised widespread control. Methodology We evaluated large-scale schistosomiasis control attempts over the past century and across the globe by identifying factors that predict control program success: snail control (e.g., molluscicides or biological control), mass drug administrations (MDA) with praziquantel, or a combined strategy using both. For data, we compiled historical information on control tactics and their quantitative outcomes for all 83 countries and territories in which: (i) schistosomiasis was allegedly endemic during the 20th century, and (ii) schistosomiasis remains endemic, or (iii) schistosomiasis has been "eliminated," or is "no longer endemic," or transmission has been interrupted. Principal Findings Widespread snail control reduced prevalence by 92 ± 5% (N = 19) vs. 37 ± 7% (N = 29) for programs using little or no snail control. In addition, ecological, economic, and political factors contributed to schistosomiasis elimination. For instance, snail control was most common and widespread in wealthier countries and when control began earlier in the 20th century. Conclusions/Significance Snail control has been the most effective way to reduce schistosomiasis prevalence. Despite evidence that snail control leads to long-term disease reduction and elimination, most current schistosomiasis control efforts emphasize MDA using praziquantel over snail control. Combining drug-based control programs with affordable snail control seems the best strategy for eliminating schistosomiasis. PMID:27441556
Barros, Cláudia Renata Castro do Rêgo; Maia, Daniela Cristina Caetano; dos Santos, Josemir Belo; Medeiros, Camila Carolina Queiroz; de Araújo, Jessica Guido
Cutaneous schistosomiasis is a rare clinical manifestation of schistosomiasis, an infectious and parasitic disease, caused in Brazil by the trematode Schistosoma mansoni. The lesions are due to the deposition of eggs or, rarely, adult worms, usually involving the genital and groin areas. Extra-genital lesions occur mainly on the torso as papules of zosteriform appearance. The case of a patient with ectopic cutaneous schistosomiasis is reported in this article, due to the rarity of its occurrence and its difficult clinical diagnosis. PMID:26982792
Molehin, Adebayo J; Rojo, Juan U; Siddiqui, Sabrina Z; Gray, Sean A; Carter, Darrick; Siddiqui, Afzal A
Schistosomiasis is a neglected tropical disease (NTD) of public health importance. Despite decades of implementation of mass praziquantel therapy programs and other control measures, schistosomiasis has not been contained and continues to spread to new geographic areas. A schistosomiasis vaccine could play an important role as part of a multifaceted control approach. With regards to vaccine development, many biological bottlenecks still exist: the lack of reliable surrogates of protection in humans; immune interactions in co-infections with other diseases in endemic areas; the potential risk of IgE responses to antigens in endemic populations; and paucity of appropriate vaccine efficacy studies in nonhuman primate models. Research is also needed on the role of modern adjuvants targeting specific parts of the innate immune system to tailor a potent and protective immune response for lead schistosome vaccine candidates with the long-term aim to achieve curative worm reduction. This review summarizes the current status of schistosomiasis vaccine development. PMID:26651503
Frederico Simões Barbosa
The subject of this conference reflects the scientific community's interest in seeking to understand the complex causal web whose various social, economic, and biological components interact in the production and reproduction of schistosomiasis and its control in relation to community participation. From the onset, the author stresses the impossibility of dealing separately with community participation, as if social components were just one more "weapon" in the arsenal for schistosomiasis con...
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 occu....... Clinically normal, but potentially exposed travel companions should be examined as well. Early diagnosis and treatment may be important in preventing the infection's serious sequelae of the infection....
Full Text Available Schistosomiasis is not known to be associated with any malignant disease other than bladder cancer. Bladder cancer is still the most common malignant tumor among males in Egypt and some African and Middle East countries. However, the frequency rate of bladder cancer has declined significantly during the last 25 years. This drop is mainly related to the control of Schistosomiasis. Many studies have elucidated the pathogenic events of Schistosomal-related bladder cancer with a suggested theory of pathogenesis. Furthermore, the disease presents with a distinct clinicopathologic profile that is quite different from bladder cancer elsewhere with younger age at presentation, more male predominance, more invasive stages, and occurrence of squamous cell carcinoma pathologic subtype. However, recent data suggest that this profile has been dramatically changed over the past 25 years leading to minimization of the differences between its features in Egypt and that in Western countries. Management of muscle-invasive localized disease is mainly surgery with 5-year survival rates of 30–50%. Although still a debatable issue, adjuvant and neoadjuvant chemotherapy and radiotherapy have improved treatment outcomes including survival and bladder preservation rates in most studies. This controversy emphasizes the need of individualized treatment options based on a prognostic index or other factors that can define the higher risk groups where more aggressive therapy is needed. The treatment for locally advanced and/or metastatic disease has passed through a series of clinical trials since 1970s. These phase II and III trials have included the use of single agent and combination of chemotherapy and radiotherapy regimens. The current standard of systemic chemotherapy of generally fit patients is now the gemcitabine–cisplatin combination. In conclusion, a changing pattern of bladder cancer in Egypt is clearly observed. This is mainly due to the success in the
Full Text Available The acute schistosomiasis is the toxemic disease that follow the Schistosoma cercariae active penetration trough screen in the immunologicaly naive vertebrate host. The clinical picture starts two to eight weeks after the first contact with the contaminated water. Susceptible patients present a syndrome comprising fever, diarrhea, toxemia and hepatosplenomegaly. Diagnosis is based on epidemiological and clinical features, presence of Schistosoma eggs in the feces, enlargement of abdominal lymph nodes by ultrasonography and by detection of high antibodies levels against the antigen keyhole limpet haemocyanin. Different rates of cure have been observed with specific medication and for the most severe clinical presentations the use of steroids reduces the systemic and allergic manifestations.
Schistosomiasis is an infection with one of a series of related trematode parasites that are endemic to at least 76 tropical and subtropical countries.Schistosomiasis affects over 200 million people in tropical and subtropical regions of South America,Africa and Asia.This paper reported more than 1500 soldiers of US troops and 560 men of Australian Air Force were affected schistosomiasis japonicum in the Leyte of the Philippines during the liberation of the Philippines from Octorber 1944 to the early months of 1945.Many troops there were affected by contaminated water with snail hosts.At first,the medical corps knew little about the situations of the schis-tosomiasis japonica in the Leyte,no preventive measure was adopted.On December 23,1944 CPT morris Goldberg discovered schistosomes first from the hospitalized soldiers while conducting a liver biopsy.Some sol-diers with markedly signs and symptoms were admitted to hospital for treatment.Preventive measure was taken since.The US sent a lot of experts to Philippines for the research of schistosomiasis japonicum,including epi-demiology,prevention,diagnosis,treatment and so on.Nineteen chemicals were used to control snail hosts. In clinical,schistosomiasis has acute and chronic stages,the manifestations are plenty and various,the liver, intestine,veins,spleen and skin etc are common sites of impingement.An extensive educational program was carried out in the troops through different means,which yielded remarkable effect,the new incidence of schis-tosomiasis dropped.Though hospitalized soldiers were a few,but there were scare and some morale and psy-chological problems among them and the other affected victims,they worried about their prognoses or being in-fected.Some patients were evacuated to United States for treatment after diagnosis,some patients were treated in Leyte.Before World War II,schistosomiasis was treated generally with trivalent antimony compounds,Fua-din and tartar emetic.In this event,no case died
R. C. Ratard
Full Text Available Kumba, a town with a population of mixed background and socio-economic status, is a new and intense focus of schistosomiasis. Although fountains provide clean water, the population still uses the river and streams which cross the town for most of its bathing, laundry and swimming activities. A multivariate analysis indicated that a local subjectÃ¢Â€Â™s age, ethnic group, knowledge about schistomiasis and the intensity of his or her contact with the river and/or stream were all significantly associated with schistosome infection. Surprisingly, a high level of knowledge about schistosomiasis was positively associated with the infection. The potential risk of schistosome infection from water contact shows that; the younger age groups are at relatively high risk and male are at more risk than females. In terms of knowledge about schistosomiasis those aged 15-19 years had the highest means score and those aged >44 years the lowest, with males having a significantly higher knowledge than females. Age, as expected and as observed in most schistosomiasis surveys, was a major determinant of schistosomiasis infection. At similar level of exposure children are more susceptible to schistosomiasis probably because they lack the immunity built up in the adults as a result of previous infections. Most surface-water contact by the children, the group most affected by schistosomiasis, occurs during playing and swimming. It is unlikely that health education will have a significant impact on this recreational high-risk behaviour.
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.
Orduña, E; Silva, F
Schistosomiasis mansoni is a tropical parasitic disease caused by a blood fluke which inhabits the portal system of humans. Fifteen pediatric patients with the acute disease were evaluated with liver and spleen scintigraphy (LSS). Clinical history, physical examination, and serum chemistries failed to reveal any other underlying systemic disease. Liver and spleen scintigraphies were performed before therapy, 7 months and 9 years after therapy with oxamniquine. LSS initially showed hepatomegaly in 93% of the patients. In the first follow up study a reactive spleen was evident in 78% of the cases, with an unchanged hepatic image. Long term follow up revealed that from the initially enlarged livers, 93% became normal. However, 47% of the spleens were abnormal. The scintigraphic changes observed in the liver over the years were those expected for an acute infection. The findings in the spleen might indicate the persistence of an immunologic reaction with a continuous trigger, probably an antibody. These observations suggest that the LSS can be used in the evaluation and follow-up of these patients. PMID:8637963
Mobarak, A B
This report provides an overview of past and current efforts to control schistosomiasis in Egypt, describes recent trends, and analyzes factors responsible for changes in transmission. For the purpose of long-term planning and developing control strategies, the country has been divided into eight geographic zones: Suez Canal Zone, Sainai, Nile Delta, Guiza, Fayoum, Middle Egypt, Upper Egypt, and the High Dam Lake Zone. Overall control priorities are examined and the strategy for each zone is described. The most recent information on changes in epidemiologic patterns of schistosomiasis in Egypt is mentioned, as well as the introduction of newer therapeutic agents. Lastly, the role of outside funding agencies in supporting schistosomiasis control is examined. PMID:7058982
Abou-Zied, Akram M.; Tarek M El-Beltagy; Hekmat M Tantawy; Rasha H Soliman; Badr, Fouad M.
Background: Schistosomiasis is an infection caused by blood flukes of the genus Schistosoma. Schistosomes are successful parasites, apparently as a result of prolonged co-evolution with their hosts. Studies done nationwide in Egypt found the highest risk of hepatitis C virus (HCV) co-infection is in those infested with schistosome without history of blood transfusions. However, the association between schistosomiasis and HCV infection is incompletely understood. Aims: The overall aim of this ...
Ezeamama, Amara E; He, Chun-La; Shen, Ye;
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...... 2009, SCORE held a series of meetings to specify empirical questions and design studies related to different schedules of PCT for schistosomiasis control in communities with high (gaining control studies) and moderate (sustaining control studies) prevalence of Schistosoma infection among school...
Full Text Available Schistosomiasis, the second major parasitic disease in the world after malaria affects at least 200 million people, 500 million being exposed to the risk of infection. It is widely agreed that a vaccine strategy wich could lead to the induction of effector mechanisms reducing the level of reinfection and ideally parasite fecundity would deeply affect the incidence of pathological manifestations as well as the parasite transmission potentialities. Extensive studies performed in the rat model have allowed the identification of novel effector mechanisms involving IgE antibodies and various inflammatory cell populations (eosinophils, macrophages and platelets whereas regulation of immune response by blocking antibodies has been evidencial. Recent epidemiological studies have now entirely confirmed in human populations the the role of IgE antibodies in the acquisition of resistance and the association of IgG4 blocking antibodies with increased susceptibility. On the basis of these concepts, several schistosome glutathion S-transferase (Sm 28 GST appears as a pronising vaccine candidate. Immunization experiments have shown that two complementary goals can be achieved: (a a partial but significant reduction of the worm population (up to 60//in rats; (b a significant reduction of parasite fecundity (up in the mice and 85//in cattle and egg viability (up to 80//. At least two distinct immunological mechanisms account for these two effects. IgE antibodies appear as a major humoral component of acquired resistance whereas IgA antibodies appear as a major humoral factor affecting parasite fecundity. These studies seem to represent a parasite diseases through the identification of potentially protective antigens and of the components of the immune response which vaccination should aim at inducing.
Andersen, L; Magnussen, Pascal; Wouters, J S; Berczy, J J; Friis, Henrik; Ali, M I
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...
Ross, Allen G. P.; Sleigh, Adrian C.; Li, Yuesheng; Davis, George M.; Williams, Gail M.; Jiang, Zheng; Feng, Zheng; Donald P McManus
Schistosomiasis japonica is a serious communicable disease and a major disease risk for more than 30 million people living in the tropical and subtropical zones of China. Infection remains a major public health concern despite 45 years of intensive control efforts. It is estimated that 865,000 people and 100,250 bovines are today infected in the provinces where the disease is endemic, and its transmission continues. Unlike the other schistosome species known to infect humans, the oriental sch...
Doumbo Ogobara K
Full Text Available Abstract Background Mass chemotherapy with praziquantel is the main control strategy for schistosomiasis in Mali. However, in the national control programme for schistosomiasis and soil-transmitted helminthiasis, infants and preschool-aged children are overlooked in preventive chemotherapy campaigns. We therefore determined the prevalence and intensity of urinary schistosomiasis in children between the ages 1-4 years in three villages across Diema health district, a rural community with endemic schistosomiasis in Mali. For Schistosoma haematobium diagnosis, a single urine sample of 10 ml obtained from each child was subjected to the standard urine filtration method. Results Of the 338 children examined 173 (51.2% were infected. Both prevalence and intensity of infection varied significantly between communities (p Conclusion Our study showed that preschool children living closely to lakes across in Mali are at high risk to be infected by schistosomiasis and contributed largely to the transmission; therefore schistosomiasis control interventions should also target infants in addition to school children and adults in endemic areas.
Full Text Available BACKGROUND: 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. METHODS/FINDINGS: 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. CONCLUSIONS/SIGNIFICANCE: 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
Catteau, Xavier; Fakhri, Anass; Albert, Valérie; Doukoure, Brahima; Noël, Jean-Christophe
Female genital schistosomiasis (FGS) is an isolated chronic form of schistosomiasis. Although most infections occur in residents of endemic areas, it has been clearly documented that brief freshwater exposure is sufficient to establish infection; thus, travellers may also be infected. The clinical manifestations of FGS are nonspecific, and lesions may mimic any neoplastic or infectious process in the female genital tract. It is important to take a careful history and physical examination, making sure to consider travel history in endemic areas. The diagnosis is confirmed by microscopy with egg identification or by serology. The standard of care for treatment is a single dose of oral praziquantel which avoids complications and substantial morbidity. Herein, we report a rare and original case of FGS in a European woman. PMID:21776398
Pao, Miranda Lee; Goffman, William
Average impact per paper, a refinement of the use of impact factor, was used to assess the quality of publications produced by a small group of sponsored researchers. The average impact per paper associated with half of the literature published by grantees has been shown to exceed those taken from the total literature at large. Moreover, this indicator appears to be stable over the five years tested. Compared with the schistosomiasis literature as a whole, the subset ...
Xiao, Han; Li, Shiyue; Chen, Xinguang (Jim); Yu, Bin; Gao, Mengting; Yan, Hong; Okafor, Chukwuemeka N.
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...
Pérez del Villar, Luis; Burguillo, Francisco J.; López-Abán, Julio; Muro, Antonio
Background Chemotherapy based on repeated doses of praziquantel is still the most effective control strategy against Schistosomiasis, however artemisinin derivatives emerged as a family of compounds with schistomicide activity. The aim of the present work is to compare the efficacy of artemisinin-based therapies in the treatment and prophylaxis of human schistosomiasis. The design of this work involved a quantitative systematic review and meta-analysis. Methodology/Principal Findings Retrieva...
Houmsou R.S; Amuta E.U; Sar T.T
Background: Urinary schistosomiasis is endemic in Nigeria and continues to pose public health challenges especially in inhabitants of rural areas. 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 to determine presence of Schist...
Full Text Available Marianette T Inobaya,1 Remigio M Olveda,1 Thao NP Chau,3 David U Olveda,2 Allen GP Ross21Department of Health, Research Institute for Tropical Medicine, Muntinlupa City, Philippines; 2Griffith Health Institute, School of Medical Sciences, Gold Coast Campus, Griffith University, Southport, Australia; 3Discipline of Public Health, Flinders University, Adelaide, AustraliaAbstract: Schistosomiasis is a neglected tropical disease that ranks second only to malaria in terms of human suffering in the tropics and subtropics. Five species are known to infect man and there are currently over 240 million people infected worldwide. The cornerstone of control to date has been mass drug administration with 40 mg/kg of praziquantel but there are problems with this approach. Human and bovine vaccines are in various stages of development. Integrated control, targeting the life cycle, is the only approach that will lead to sustainability and future elimination.Keywords: schistosomiais, morbidity, treatment and control, mass drug administration
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
Barbosa, F S
The subject of this conference reflects the scientific community's interest in seeking to understand the complex causal web whose various social, economic, and biological components interact in the production and reproduction of schistosomiasis and its control in relation to community participation. From the onset, the author stresses the impossibility of dealing separately with community participation, as if social components were just one more "weapon" in the arsenal for schistosomiasis control. This study begins with a brief historical review of the 71 years of control activities with this endemic disease, stressing the enormous efforts and huge expenditures in this field vis-à-vis the limited results, despite the extraordinary technological development of specific, classical control inputs such as new treatment drugs and molluscicides. The article then discusses the various strategies used in control programs, emphasizing ideological consistencies and contradictions. Interactions at the macro and micro levels are discussed, as are the determinants and risk factors involved in producing the disease's endemicity. Unequal occupation of space leaves the segregated portion of the population exposed to extremely favorable conditions for transmission of the disease. This raises the issue of how to control an endemic disease which is so closely linked to the way of life imposed on the population. The study challenges the classical control model and suggests an alternative model now undergoing medium-term investigation in the States of Espirito Santo, and Pernambuco, Brazil. The author concludes that we do not need new strategies, but a new control model, contrary to the prevailing classical model in both concept and practice. From the conceptual point of view, the new model mentioned above is different from others in that schistosomiasis control is seen from a social perspective stressing the population's accumulated knowledge in addition to the building of shared
Gomes, Luciana Inácia; Enk, Martin Johannes; Rabello, Ana
In light of the World Health Organization's initiative to extend schistosomiasis morbidity and mortality control programs by including a disease elimination strategy in low endemic settings, this paper reviews diagnostic tools described during the last decades and provide an overview of ongoing efforts in making an efficient diagnostic tool available worldwide. A literature search on PubMed using the search criteria schistosomiasis and diagnosis within the period from 1978 to 2013 was carried out. Articles with abstract in English and that used laboratory techniques specifically developed for the detection of schistosomiasis in humans were included. Publications were categorized according to the methodology applied (parasitological, immunological, or molecular) and stage of development (in house development, limited field, or large scale field testing). The initial research generated 4,535 publications, of which only 643 met the inclusion criteria. The vast majority (537) of the publications focused on immunological techniques; 81 focused on parasitological diagnosis, and 25 focused on molecular diagnostic methods. Regarding the stage of development, 307 papers referred to in-house development, 202 referred to limited field tests, and 134 referred to large scale field testing. The data obtained show that promising new diagnostic tools, especially for Schistosoma antigen and deoxyribonucleic acid (DNA) detection, which are characterized by high sensitivity and specificity, are being developed. In combination with international funding initiatives these tools may result in a significant step forward in successful disease elimination and surveillance, which is to make efficient tests accessible and its large use self-sustainable for control programs in endemic countries. PMID:24553804
Luciana Inácia Gomes
Full Text Available In light of the World Health Organization's initiative to extend schistosomiasis morbidity and mortality control programs by including a disease elimination strategy in low endemic settings, this paper reviews diagnostic tools described during the last decades and provide an overview of ongoing efforts in making an efficient diagnostic tool available worldwide. A literature search on PubMed using the search criteria schistosomiasis and diagnosis within the period from 1978 to 2013 was carried out. Articles with abstract in English and that used laboratory techniques specifically developed for the detection of schistosomiasis in humans were included. Publications were categorized according to the methodology applied (parasitological, immunological, or molecular and stage of development (in house development, limited field, or large scale field testing. The initial research generated 4,535 publications, of which only 643 met the inclusion criteria. The vast majority (537 of the publications focused on immunological techniques; 81 focused on parasitological diagnosis, and 25 focused on molecular diagnostic methods. Regarding the stage of development, 307 papers referred to in-house development, 202 referred to limited field tests, and 134 referred to large scale field testing. The data obtained show that promising new diagnostic tools, especially for Schistosoma antigen and deoxyribonucleic acid (DNA detection, which are characterized by high sensitivity and specificity, are being developed. In combination with international funding initiatives these tools may result in a significant step forward in successful disease elimination and surveillance, which is to make efficient tests accessible and its large use self-sustainable for control programs in endemic countries.
Leite, Luiz Arthur Calheiros; Pimenta Filho, Adenor Almeida; Ferreira, Rita de Cássia dos Santos; da Fonseca, Caíque Silveira Martins; dos Santos, Bianka Santana; Montenegro, Silvia Maria Lucena; Lopes, Edmundo Pessoa de Almeida; Domingues, Ana Lúcia Coutinho; Owen, James Stuart; Lima, Vera Lucia de Menezes
Background 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. Methodology/Principal Findings 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. Conclusion/Significance 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. PMID:26267788
Full Text Available The control of schistosomiasis has been spectacularly successful in terms of controlling endemicity and severity of the disease during the last 50 years. It can be categorized into two stages. From 1955 through 1980, the transmission-control strategy had been widely and successfully carried out. By the end of 1980, the epidemic of schistosomiasis was successfully circumscribed in certain core regions including areas at the middle and low reaches of the Yangtze River and some mountainous areas in Sichuan and Yunnan provinces, where control of schistosomiasis had been demonstrated to be very difficult to be sustained. Therefore, since 1980, schistosomiasis control in China has been modified to employ a stepwise strategy, based on which morbidity control has been given priorities and if possible transmission control has been pursued. However, since snail-ridden areas remain unchanged so far, reinfections occur frequently. This necessitates a maintenance phase to consolidate the achievements in the control of schistosomiasis. In the mean time, we are challenged with some environmental, social and economical changes in terms of controlling schistosomiasis. Successfully controlling schistosomiasis in China is still a long-term task but will be achieved without doubt along with the economic development and the promotion of living and cultural standard of people.
Trainor-Moss, Santiago; Mutapi, Francisca
Schistosomiasis is a debilitating neglected tropical disease caused by schistosome worms. Global efforts to control schistosomiasis rely predominantly on mass drug administration of the drug praziquantel to populations at risk of infection. We review the history of schistosome drug development and the current position of schistosome drug research. We conclude that with no additional candidates currently in the anti-schistosome drug clinical trial pipeline, a practical and necessary approach is to optimise the health benefits from praziquantel. We offer suggestions of where and how this can be achieved. We also highlight knowledge gaps in the utility of praziquantel particularly in the treatment of chronic schistosomiasis, which includes fibrosis, organomegaly and cervical lesions associated with female genital schistosomiasis. PMID:26508363
Longxing Qi; Jing-an Cui
A compartmental model is established for schistosomiasis with praziquantel resistance. The model considers the impact of genetic resistance and drug treatment on the transmission of schistosomiasis. We calculate the basic reproductive number and discuss the existence and stability of disease-free equilibrium, boundary equilibrium, and coexistence equilibrium. Our analysis shows that regardless of whether drug treatment leads to the emergence of resistance, once the impact of genetic resistanc...
Frederico Simões Barbosa
Full Text Available The subject of this conference reflects the scientific community's interest in seeking to understand the complex causal web whose various social, economic, and biological components interact in the production and reproduction of schistosomiasis and its control in relation to community participation. From the onset, the author stresses the impossibility of dealing separately with community participation, as if social components were just one more "weapon" in the arsenal for schistosomiasis control. This study begins with a brief historical review of the 71 years of control activities with this endemic disease, stressing the enormous efforts and huge expenditures in this field vis-à-vis the limited results, despite the extraordinary technological development of specific, classical control inputs such as new treatment drugs and molluscicides. The article then discusses the various strategies used in control programs, emphasizing ideological consistencies and contradictions. Interactions at the macro and micro levels are discussed, as are the determinants and risk factors involved in producing the disease's endemicity. Unequal occupation of space leaves the segregated portion of the population exposed to extremely favorable conditions for transmission of the disease. This raises the issue of how to control an endemic disease which is so closely linked to the way of life imposed on the population. The study challenges the classical control model and suggests an alternative model now undergoing medium-term investigation in the States of Espirito Santo, and Pernambuco, Brazil. The author concludes that we do not need new strategies, but a new control model, contrary to the prevailing classical model in both concept and practice. From the conceptual point of view, the new model mentioned above is different from others in that schistosomiasis control is seen from a social perspective stressing the population's accumulated knowledge in addition to the
D. Danso-Appiah (Anthony); W.A. Stolk (Wilma); K.M. Bosompem (Kwabena); J. Otchere (Joseph); C.W.N. Looman (Caspar); J.D.F. Habbema (Dik); S.J. de Vlas (Sake)
textabstractBackground: Schistosomiasis causes long-term illness and significant economic burden. Morbidity control through integration within existing health care delivery systems is considered a potentially sustainable and cost-effective approach, but there is paucity of information about health-s
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. PMID:22590876
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....
Full Text Available BACKGROUND: 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. METHODS AND FINDINGS: 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. CONCLUSIONS: 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.
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.
Helleberg, Marie; Thybo, Søren
INTRODUCTION: The purpose of the study was to describe symptoms and diagnosis of schistosomiasis in travellers and immigrants based on patients diagnosed and treated at the State University Hospital in Copenhagen in 2003-2008. MATERIAL AND METHODS: Retrospective review of patient records. RESULTS......: A total of 49 patients (39 travellers and ten immigrants) were diagnosed with schistosomiasis. All patients except one were infected in Africa. There was considerable variation in clinical manifestations between travellers and immigrants. Eggs were detected in urine, faeces and/or biopsy from 18...... patients, whereas 31 patients were diagnosed solely by serology. DISCUSSION: Travellers with schistosomiasis are often asymptomatic or have unspecific symptoms, while immigrants may present with severe complications to the infection. Because symptoms can develop years after the infection and due to the...
Catherine A Gordon
Full Text Available The cause of zoonotic schistosomiasis in the Philippines is Schistosoma japonicum, which infects up to 46 mammalian hosts, including humans and bovines. In China, water buffaloes have been identified as major reservoir hosts for schistosomiasis japonica, contributing up to 75% of human transmission. In the Philippines, water buffaloes (carabao; Bubalus bubalis carabanesis have, historically, been considered unimportant reservoirs. We therefore revisited the possible role of bovines in schistosome transmission in the Philippines, using the recently described formalin-ethyl acetate sedimentation (FEA-SD technique and a qPCR assay to examine fecal samples from 153 bovines (both carabao and cattle from six barangays in Northern Samar. A high prevalence of S. japonicum was found using qPCR and FEA-SD in both cattle (87.50% and 77.08%, respectively and carabao (80.00% and 55.24%, respectively. The average daily egg output for each bovine was calculated at 195,000. High prevalence and infection intensity of F. gigantica was also found in the bovines by qPCR and FEA-SD (95.33% and 96.00%, respectively. The identification of bovines as major reservoir hosts for S. japonicum transmission suggests that bovine treatment and/or vaccination, as one becomes available, should be included in any future control program that aims to reduce the disease burden due to schistosomiasis in the Philippines.
Rufin K Assaré; Knopp, Stefanie; N'Guessan, Nicaise A.; Yapi, Ahoua; Yves-Nathan T. Tian-Bi; Patrick K. Yao; Coulibaly, Jean T.; Ouattara, Mamadou; Meïté, Aboulaye; FENWICK, ALAN; N'Goran, Eliézer K.; Utzinger, Jürg
Background Schistosomiasis is a parasitic disease that occurs in the tropics and subtropics. The mainstay of control is preventive chemotherapy with praziquantel. In Africa, an estimated 230 million people require preventive chemotherapy. In western Côte d’Ivoire, infections with Schistosoma mansoni are widespread. To provide an evidence-base for programme decisions about preventive chemotherapy to sustain control of schistosomiasis, a 5-year multi-country study with different treatment arms ...
Kallestrup, Per; Zinyama, Rutendo; Gomo, Exnevia; Butterworth, Anthony E; van Dam, Govert J; Gerstoft, Jan; Erikstrup, Christian; Ullum, Henrik
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....
Person, Bobbie; Ali, Said M.; A’Kadir, Faiza M.; Ali, Jamal N.; Mohammed, Ulfat A.; Mohammed, Khalfan A.; Rollinson, David; Knopp, Stefanie
Background 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. Methodology 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. Principal Findings 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. Conclusions/Significance 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. PMID:27399310
Cecília Pereira de Souza
Full Text Available A review of the methodology recommended by the World Health Organization for the use of molluscicides for the control of snail vectors of schistosomiasis is presented. Discussion of the principle molluscicides used, their advantages and disadvantages, the techniques and equipment required for their application and evaluation of effect as well as the biological control of snails is included.
Cecília Pereira de Souza
A review of the methodology recommended by the World Health Organization for the use of molluscicides for the control of snail vectors of schistosomiasis is presented. Discussion of the principle molluscicides used, their advantages and disadvantages, the techniques and equipment required for their application and evaluation of effect as well as the biological control of snails is included.
Merrifield, Maureen; Hotez, Peter J; Beaumier, Coreen M; Gillespie, Portia; Strych, Ulrich; Hayward, Tara; Bottazzi, Maria Elena
Several candidate human schistosomiasis vaccines are in different stages of preclinical and clinical development. The major targets are Schistosoma haematobium (urogenitial schistosomiasis) and Schistosoma mansoni (intestinal schistosomiasis) that account for 99% of the world's 252 million cases, with 90% of these cases in Africa. Two recombinant S. mansoni vaccines - Sm-TSP-2 and Sm-14 are in Phase 1 trials, while Smp80 (calpain) is undergoing testing in non-human primates. Sh28GST, also known as Bilhvax is in advanced clinical development for S. haematobium infection. The possibility remains that some of these vaccines may cross-react to target both schistosome species. These vaccines were selected on the basis of their protective immunity in preclinical challenge models, through human immune-epidemiological studies or both. They are being advanced through a combination of academic research institutions, non-profit vaccine product development partnerships, biotechnology companies, and developing country vaccine manufacturers. In addition, new schistosome candidate vaccines are being identified through bioinformatics, OMICs approaches, and moderate throughput screening, although the full potential of reverse vaccinology for schistosomiasis has not yet been realized. The target product profiles of these vaccines vary but many focus on vaccinating children, in some cases following mass treatment with praziquantel, also known as vaccine-linked chemotherapy. Several regulatory pathways have been proposed, some of which rely on World Health Organization prequalification. PMID:27036511
In schistosomiasis calcification of the urinary bladder are characteristic signs that allow a corresponding diagnosis in endemic regions. Problems concerning differential diagnosis occur only in very rare cases. The calcifications of the bladder can be easily detected by native diagnostics. A late complication in an affected bladder is often a bladder carcinoma. (orig.)
Kotze, Sebastian Ranzi; Zinyama-Gutsire, Rutendo; Kallestrup, Per; Benn, Christine Stabell; Gomo, Exnevia; Gerstoft, Jan; van Dam, Govert; Mortensen, Ole Hartvig; Ullum, Henrik; Erikstrup, Christian
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...
Abou-Zeid Alaa Hammad
Full Text Available Abstract Background Schistosomiasis remains a major health problem at global and national levels, contributing to the vulnerability of the poor people in Sudan. Southern Kordofan is affected by Schistosomiasis but the disease prevalence was unknown. Methods 1826 adults were recruited in a community-based survey. Each recruited subject submitted at least 10 ml urine and one stool sample; they were also interviewed and filled in a questionnaire. Results 1826 adults were recruited in a community-based survey. Each recruited subject submitted at least 10 ml urine and one stool sample; they were also interviewed and filled in a questionnaire. The prevalence of S. haematobium was 6.9 % among the adult population. We estimated S. mansoni prevalence as 0.0 %. S. haematobium infection was focally distributed at the village level. The infection was associated with non preference of latrine use – if available, use of open water source for household affairs such as cleaning and also with the history of schistosomiasis treatment. The prevalence of soil transmitted helminths (STH was also reported as high at 7.8 %, and two species were identified; Hymenolepis nana and Giardia lamblia. Conclusion Schistosomiasis is a significant health problem among the adult population in Southern Kordofan. The estimated prevalence will serve as a guide in developing a Schistosomiasis Control Program and applying treatment plans.
G.G. Baaten; G.J. Sonder; T. van Gool; J.A. Kint; A. van den Hoek
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 advi
Rapado, Ludmila Nakamura; Pinheiro, Alessandro de Sá; Lopes, Priscila Orechio de Moraes Victor; Fokoue, Harold Hilarion; Scotti, Marcus Tullius; Marques, Joaquim Vogt; Ohlweiler, Fernanda Pires; Borrely, Sueli Ivone; Pereira, Carlos Alberto de Bragança; Kato, Massuo Jorge; Nakano, Eliana; Yamaguchi, Lydia Fumiko
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. M...
Grimes, Jack E. T.; David Croll; Harrison, Wendy E.; Jürg Utzinger; Freeman, Matthew C.; Templeton, Michael R.
BACKGROUND: 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. METHODOLOGY: 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 w...
Hu, Yi; Zhang, Zhijie; Chen, Yue; Wang, Zengliang; Gao, Jie; Tao, Bo; Jiang, Qiulin; Jiang, Qingwu
Background The recent rebounds of schistosomiasis in the middle and lower reaches of the Yangtze River pose a challenge to the current control strategies. In this study, identification of potential high risk snail habitats was proposed, as an alternative sustainable control strategy, in Xingzi County, China. Parasitological data from standardized surveys were available for 36,208 locals (aged between 6–65 years) from 42 sample villages across the county and used in combination with environmen...
Kabatereine, Narcis; Fleming, Fiona; Thuo, Wangechi; Tinkitina, Benjamin; Edridah M Tukahebwa; Fenwick, Alan
Background Over 200,000 people, most of them infected with Schistosoma mansoni inhabit 150 islands in Lake Victoria in Uganda. Although a programme to control the disease has been ongoing since 2003, its implementation in islands is inadequate due to high transport costs on water. In 2011 and 2012, the Global Network for Neglected Tropical Diseases (GNNTD) through Schistosomiasis Control Initiative (SCI) provided financial support to ease treatment delivery on the islands and over the period,...
Fu, Chi-Ling; Odegaard, Justin I.; Hsieh, Michael H.
Urogenital schistosomiasis, Schistosoma haematobium worm infection, afflicts millions of people with egg-triggered, fibrotic bladder granulomata. Despite the significant global impact of urogenital schistosomiasis, the mechanisms of bladder granulomogenesis and fibrosis are ill defined due to the prior lack of tractable animal models. We combined a mouse model of urogenital schistosomiasis with macrophage-depleting liposomal clodronate (LC) to define how macrophages mediate bladder granulomog...
Madinga Ntwan, Joule; Linsuke, Sylvie; Mpabanzi, Liliane; Meurs, Lynn; Kanobana, Kirezi; Speybroeck, Niko; Lutumba, Pascal; Polman, Katja
Schistosomiasis is a poverty-related parasitic infection, leading to chronic ill-health. For more than a century, schistosomiasis has been known to be endemic in certain provinces of the Democratic Republic of Congo (DRC). However, a clear overview on the status of the disease within the country is currently lacking, which is seriously hampering control. Here, we review the available information on schistosomiasis in DRC of the past 60 years. Findings and data gaps are discussed in the perspe...
Wu, Wei; Feng, Aicheng; Huang, Yixin
Among the three main schistosomes (Schistosoma japonicum, Schistosoma mansoni, and Schistosoma haematobium) known to infect humans, S. japonicum causes the most serious pathological lesions. In China, only schistosomiasis japonica is transmitted. From the 1950s, massive epidemiological investigations and active control measures for schistosomiasis japonica have been carried out. At the early stage of schistosomiasis control program, there were about 12 million schistosomiasis patients, and about 5% of schistosomiasis patients belong to advanced patients, which was 600,000. After more than a half century of active schistosomiasis control work, the schistosomiasis situation has been reduced markedly. The nearest epidemiological investigation showed that, by the end of 2012, there were still 240,000 schistosomiasis patients with the descent rate of 98% and 30,000 advanced patients with the descent rate of 95%. This paper reviews the rich experiences of advanced schistosomiasis research and control in China, including that the epidemiology researches confirm there is a family aggregation of advanced schistosomiasis and advanced schistosomiasis patients have no significance to the schistosomiasis transmission in transmission-interrupted areas but still are an infection source in endemic areas; pathogenic mechanism researches verify that genetic factors and immunoregulation play important roles in the disease developing process; ultrasound image examinations are used not only in the diagnosis and differential diagnosis of advanced schistosomiasis but also in the guidance of treatment and evaluation of therapeutic effects and, furthermore, in the risk predictions of portal hypertension and upper gastrointestinal hemorrhage; clinical practices demonstrate that praziquantel can be used in most of advanced schistosomiasis patients, and the therapy not only can interrupt the schistosomiasis transmission somewhat but also is favorable for liver fibrosis improvement; the
Full Text Available BACKGROUND: 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. METHODOLOGY: 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. PRINCIPAL FINDINGS: 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. CONCLUSIONS/SIGNIFICANCE: 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.
Dongbao, Y; Ross, A G; Musheng, X; Yuesheng, L; Yan, C
A region-wide sampling survey was conducted in 1995 in order to evaluate the current epidemiological status of schistosomiasis japonica in Hunan Province, China. A total of 45,590 humans and 3,726 domestic animals, from 52 villages, were examined parasitologically and/or serologically for current Schistosoma japonicum infections. In uncontrolled endemic areas (43 villages) the overall human prevalence of S. japonicum was 7.81% across the different geographical subtypes. The geometric mean intensity of infection was 17.71 eggs per gram (epg) among infected individuals and only 1.25 epg in the general population. The bovine prevalence, as determined by the hatching test, was 9.63% in the uncontrolled endemic villages. Only one sero-positive (by indirect hemagglutination assay) child was found among 1,072 children tested aged 10-14 years in the 9 endemic villages under effective control. No infection was confirmed by the Kato-Katz thick smear stool examination. When the results of this survey were compared to those seen at baseline (1989) an overall reduction of 45.65% was seen in the human prevalence but no significant change was apparent in the lake-beach ecotype. Additionally, there was more than a 60% reduction in the prevalence among bovines over the same sampling period. The results demonstrate that the World Bank Loan Schistosomiasis Program was successful in achieving its most basic objectives for this province - to reduce human and bovine infections by 40%. PMID:10928356
Full Text Available A schistosomiasis model is proposed including single schistosomes, paired schistosomes, snails, and the latent period of infected snails. A reasonable sex ratio of schistosomes and the minimum mating function are considered. A threshold condition determining the stability of the system is given, and the stability of equilibrium for the model is shown. The impact of the latent period of infected snails on schistosomiasis transmission can be found through numerical simulations. Finally, preferable control strategies are obtained by sensitivity analyses. Killing snails may be the preferred control measure. If we choose chemotherapy, we should use some drugs which are sufficient for reducing egg-associated pathology, since paired schistosomes are mostly harmful to definitive hosts.
Results are reported from studies on the immunodiagnosis of filariasis, schistosomiasis and malaria which have been carried out under the auspices of the UNDP/World Bank/WHO Special Programme for Research and Training in Tropical Diseases. These studies include an evaluation of the RIPEGA and IRMA for the detection of filarial antigens; the selection and standardization of schistosome antigens for diagnostic purposes; and the development of tests for the detection of malaria antigens and antibodies. (author)
@@ INTRODUCTION Schistosomiasis is a chronic parasitic disease caused by a trematode blood fluke of the genus schistosoma that belongs to the schistosomatidae family.The ancient Egyptians contracted the disease more than 4 000 years ago.It was recognized through haematuria,the main sign of urinary bilharziasis was recorded in the Kahun papyrus 1900 B.C.as"a-a-a" disease.
Following an intensive public health eradication program, the focus of schistosomiasis mansoni at Salalah in Southern Oman (the only focus of schistosomiasis in Oman), appeared to have been eradicated in 1994. Since the vector snails for schistosomiasis mansoni (and also for S. haematobium) were widely endemic in fresh water springs at Salalah, and reintroduction of introduction (or introduction in case of S.haematobium), was possible, we undertook a prospective study in 1995 for schistosomiasis in our patients at the Sultan Qaboos University Hospital (SQUH) and to obtain evidence of visits by these patients to Salalah. From May 1995 to May 2000, Omani and expatriate patients presenting at SQUH were evaluated for possible schistosomiasis (residence in an endemic region, suggestive clinical features) by a search for ova in stool, urine, or in tissue biopsies, or when ova were absent, by serodiagnosis. A retrospective survey of schistosomiasis patients diagnosed in SQUH from 1990 to April 1995 was also performed. Ministry of Health (MOH) data on reports of schistosomiasis (a notifiable disease) in Oman from 1991 to 2000 were obtained. Thirty patients with schistosomiasis were identified, 10 retrospectively and 20 in prospective study. Patients were aged 9 to 60 years, and 25 of them (10 Omanis, 14 Egyptians, 1 Sudanese) contracted the infection in Africa, while 5 Omanis became infected in Salalah (3 in 99). Twelve patients had schistosomiasis mansoni, 6 had schistosomiasis. Haematobia, and in the rest, infection by both parasites was confirmed or possible. The most common presentation (23%) was hepatosplenic schistosomiasis with portal hypertension. No patient admitted to contaminating fresh water with excreta in Salalah. MOH data revealed 3 to 14 cases of schistosomiasis were reported annually between 1991 and 2000, and that all schistosomiasis cases reported from 1994 1998 originated from Africa. Schistosomiasis remains an important health problem in Oman. Many
Huang, Y; Manderson, L
Social, cultural, behavioural and economic factors interact with local environmental and ecological factors to produce extraordinary variation in the epidemiology of schistosomiasis, including with respect to prevalence and intensity of infection and the potential for control. This article reviews the literature on schistosomiasis infection, primarily derived from African studies, to identify its major social themes. Research has demonstrated a strong link between economic development strategies, where irrigation has been introduced to boost agricultural production, and the increased transmission of infection. Water-contact studies have provided the fullest and most detailed descriptions of social risk factors, and have isolated age, sex, religion and occupation as primary risk factors. However, fuller explorations of the social and cultural context of infection have yet to be undertaken. The social context of water-related behaviour and patterns of water use within communities and households, the intersection of social and economic activities, and the significance that people give to these activities, remains poorly explored, and although research papers concerned with community-based interventions refer to poor community understanding of the cause, prevention and treatment of the disease, this domain has also received little scholarly attention. Finally, economic studies have focused primarily on working capacity, and extrapolated these findings to generalize about the impact that this might have on productivity, but have yet to address either household or community costs of schistosomiasis infection. PMID:1359746
Solarin Adewale RT
Full Text Available Abstract Background The control of urinary schistosomiasis in Ogun State, Nigeria remains inert due to lack of reliable data on the geographical distribution of the disease and the population at risk. To help in developing a control programme, delineating areas of risk, geographical information system and remotely sensed environmental images were used to developed predictive risk maps of the probability of occurrence of the disease and quantify the risk for infection in Ogun State, Nigeria. Methods Infection data used were derived from carefully validated morbidity questionnaires among primary school children in 2001–2002, in which school children were asked among other questions if they have experienced "blood in urine" or urinary schistosomiasis. The infection data from 1,092 schools together with remotely sensed environmental data such as rainfall, vegetation, temperature, soil-types, altitude and land cover were analysis using binary logistic regression models to identify environmental features that influence the spatial distribution of the disease. The final regression equations were then used in Arc View 3.2a GIS software to generate predictive risk maps of the distribution of the disease and population at risk in the state. Results Logistic regression analysis shows that the only significant environmental variable in predicting the presence and absence of urinary schistosomiasis in any area of the State was Land Surface Temperature (LST (B = 0.308, p = 0.013. While LST (B = -0.478, p = 0.035, rainfall (B = -0.006, p = 0.0005, ferric luvisols (B = 0.539, p = 0.274, dystric nitosols (B = 0.133, p = 0.769 and pellic vertisols (B = 1.386, p = 0.008 soils types were the final variables in the model for predicting the probability of an area having an infection prevalence equivalent to or more than 50%. The two predictive risk maps suggest that urinary schistosomiasis is widely distributed and occurring in all the Local Government Areas (LGAs
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.
Duplex sonography study in schistosomiasis portal hypertension: characterization of patients with and without a history of variceal bleeding Dopplerfluxometria portal na esquistossomose hepatoesplênica com e sem antecedentes de hemorragia por varizes esofágicas
Severino Marcos Borba de Arruda; Victorino Spinelli Toscano Barreto; Fernando José do Amaral
BACKGROUND: Presinusoidal portal hypertension with frequent episodes of upper gastrointestinal variceal bleeding are hallmarks of hepatosplenic Manson’s schistosomiasis; a clinical form that affects about 5% of Brazilians who are infected by Schistosoma mansoni. AIMS: To evaluate duplex sonography findings in patients with hepatosplenic Manson’s schistosomiasis with and without upper gastrointestinal variceal hemorrhage. METHODS: A cross-sectional study was performed whereby 27 consecutive pa...
Madinga, Joule; Linsuke, Sylvie; Mpabanzi, Liliane; Meurs, Lynn; Kanobana, Kirezi; Speybroeck, Niko; Lutumba, Pascal; Polman, Katja
Schistosomiasis is a poverty-related parasitic infection, leading to chronic ill-health. For more than a century, schistosomiasis has been known to be endemic in certain provinces of the Democratic Republic of Congo (DRC). However, a clear overview on the status of the disease within the country is currently lacking, which is seriously hampering control. Here, we review the available information on schistosomiasis in DRC of the past 60 years. Findings and data gaps are discussed in the perspective of upcoming control activities.An electronic literature search via PubMed complemented by manual search of non-peer-reviewed articles was conducted up to January 2015. The search concerned all relevant records related to schistosomiasis in the DRC from January 1955 onwards. A total of 155 records were found, of which 30 met the inclusion criteria. Results were summarized by geographical region, mapped, and compared with those reported sixty years ago. The available data reported schistosomiasis in some areas located in 10 of the 11 provinces of DRC. Three species of Schistosoma were found: S. mansoni, S. haematobium and S. intercalatum. The prevalence of schistosomiasis varied greatly between regions and between villages, with high values of up to 95 % observed in some communities. The overall trend over 60 years points to the spread of schistosomiasis to formerly non-endemic areas. The prevalence of schistosomiasis has increased in rural endemic areas and decreased in urban/peri-urban endemic areas of Kinshasa. Hepatosplenomegaly, urinary tract lesions and anaemia were commonly reported in schistosomiasis endemic areas but not always associated with infection status.The present review confirms that schistosomiasis is still endemic in DRC. However, available data are scattered across time and space and studies lack methodological uniformity, hampering a reliable estimation of the current status of schistosomiasis in DRC. There is a clear need for updated prevalence data
Duval, David; Galinier, Richard; Mouahid, Gabriel; Toulza, Eve; Allienne, Jean François; Portela, Julien; Calvayrac, Christophe; Rognon, Anne; Arancibia, Nathalie; Mitta, Guillaume; Théron, André; Gourbal, Benjamin
Background 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. Methodology/Principal findings 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. Conclusions/Significance 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. PMID:25719489
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.
Full Text Available Background: Schistosomiasis is one of the major communicable diseases of public health and socioeconomic importance in developing countries. This study assessed the situation of schistosomiasis among villagers of the New Halfa Agricultural Scheme, Sudan.Methods: An epidemiological survey was carried out in three randomly selected residential sites: Village 19, Village 26 and Talat shagrat Camp, from October to December 2013. Feces and urine samples were collected from 2433 individual (1195 male and 1238 female and examined for schistosomiasis infection. The prevalence and intensity of infection were calculated according to study sites and participants’ sex and age-group.Results: There was no infection with Schistosoma haematobium among the examined individuals, while the overall prevalence of S. mansoni infection was 27.4% and the mean intensity among those infected was 261.1 eggs per gram (epg. A high prevalence and intensity of infection was found among the residents of Talat shagrat Camp, followed by the other two villages. The prevalence of infection among males was 41.4%, and among females was 13.9%. On the other hand, the intensity of infection among females was 293.4 epg and among males 187.6 epg. A high prevalence of infection was found in the age-groups 11-20 years and > 50 years. High intensity of infection was present in the age-groups 31-40 years and > 50 years.Conclusion: The finding of the study shows the need for an integrated control program against schistosomiasis. Mass treatment, provision of adequate clean-water supply and combating the intermediate snail host are suggested.
Fataar, S; Bassiony, H; Hamed, M S; Ghoneim, I; Satyanath, S; Hebbar, H G; Elgindy, N N; Hanna, R M
Rectocolonic calcification was detected radiographically in 17 sites in 14 patients undergoing excretory urography for the assessment of urinary schistosomiasis. The right colon was involved in 11 sites, the rectum in four, and the left colon in two. The pattern of calcification varied according to the degree of bowel distension. A laminar pattern was common to all sites and occurred when the rectum or colon was distended with air, feces, or barium. A laminar or irregular amorphous density was found in the empty colon, whereas the calcified, empty rectum had a corrugated pattern. Rectocolonic calcification is probably the most common radiographic manifestation of schistosomal infestation of the gastrointestinal tract. PMID:6609576
Zhou, Xiao-Nong; Wang, Li-Ying; Chen, Ming-Gang; Wang, Tian-Ping; Guo, Jia-Gang; Wu, Xiao-Hua; Jiang, Qing-Wu; Zheng, Jiang; Chen, Xian-Yi
The World Bank Loan Project, by far the largest effort in China for schistosomiasis control since control activities were initiated in the mid 1950s, was carried out for a 9-year period commencing in 1992 in the 8 provinces where Schistosoma japonicum remained endemic when the project started. To evaluate its impact, a retrospective economic evaluation was done in 2001. Six representative counties, i.e. Huarong in Hunan province, Qianjiang in Hubei province, Yugan in Jiangxi province, Tongling in Anhui province, Xichang in Sichuan province and Dali in Yunnan province, were selected for the study. The total financial input in these counties from 1992 to 2000 was RMB Yuan 90.334 million with the World Bank loan accounting for 40.9%. Control efforts resulted in reduction of human prevalence rates in the six counties from 0.7-9.0% in 1992 to 0.1-2.7% in 2000. With regard to S. japonicum infection in bovines, a high reduction was observed in Qianjiang, and smaller decreases were noted in four counties, while there was an increase in Dali. In general, the areas infested by the intermediate host snail fluctuated around the initial level. The net benefit-cost ratio was 6.20, which means that this project gained US$ 6.20 for every dollar spent. The correlation coefficients of the net benefit-cost ratio to the human and bovine infection rates at the beginning of the project were 0.55 and 0.66, respectively. It is conceivable that further progress in schistosomiasis control is an important feature for sustained growth of the local economy, particularly in areas where control of the disease has been most challenging. PMID:16154104
Xiao, Yuan; Lu, Yi; Hsieh, Michael; Liao, Joseph; Wong, Pak Kin
Schistosomiasis is a parasitic disease affecting over 200 million people worldwide. This study reports the design and development of a microfiltration device for isolating schistosome eggs in urine for rapid diagnostics of urogenital schistosomiasis. The design of the device comprises a linear array of microfluidic traps to immobilize and separate schistosome eggs. Sequential loading of individual eggs is achieved autonomously by flow resistance, which facilitates observation and enumeration of samples with low-abundance targets. Computational fluid dynamics modeling and experimental characterization are performed to optimize the trapping performance. By optimizing the capture strategy, the trapping efficiency could be achieved at 100% with 300 μl/min and 83% with 3000 μl/min, and the filtration procedure could be finished within 10 min. The trapped eggs can be either recovered for downstream analysis or preserved in situ for whole-mount staining. On-chip phenotyping using confocal laser fluorescence microscopy identifies the microstructure of the trapped schistosome eggs. The device provides a novel microfluidic approach for trapping, counting and on-chip fluorescence characterization of urinal Schistosoma haematobium eggs for clinical and investigative application. PMID:27124499
Xiao, Yuan; Lu, Yi; Hsieh, Michael; Liao, Joseph; Wong, Pak Kin
Schistosomiasis is a parasitic disease affecting over 200 million people worldwide. This study reports the design and development of a microfiltration device for isolating schistosome eggs in urine for rapid diagnostics of urogenital schistosomiasis. The design of the device comprises a linear array of microfluidic traps to immobilize and separate schistosome eggs. Sequential loading of individual eggs is achieved autonomously by flow resistance, which facilitates observation and enumeration of samples with low-abundance targets. Computational fluid dynamics modeling and experimental characterization are performed to optimize the trapping performance. By optimizing the capture strategy, the trapping efficiency could be achieved at 100% with 300 μl/min and 83% with 3000 μl/min, and the filtration procedure could be finished within 10 min. The trapped eggs can be either recovered for downstream analysis or preserved in situ for whole-mount staining. On-chip phenotyping using confocal laser fluorescence microscopy identifies the microstructure of the trapped schistosome eggs. The device provides a novel microfluidic approach for trapping, counting and on-chip fluorescence characterization of urinal Schistosoma haematobium eggs for clinical and investigative application. PMID:27124499
Full Text Available Schistosomiasis is one of the most common neglected tropical diseases, especially in the developing countries in Africa, Asia and South America, with Nigeria having the greatest number of cases of schistosomiasis worldwide. This community-based study aims to evaluate the knowledge, attitude and practices (KAP regarding schistosomiasis among rural Hausa communities in Kano State, Nigeria.A cross-sectional study was carried out among 551 participants from Hausa communities in five local government areas in Kano State, North Central Nigeria. Demographic, socioeconomic and environmental information as well as KAP data were collected using a pre-tested questionnaire. Moreover, faecal and urine samples were collected and examined for the presence of Schistosoma mansoni and S. haematobium eggs respectively.The overall prevalence of schistosomiasis was 17.8%, with 8.9% and 8.3% infected with S. mansoni and S. haematobium respectively, and 0.5% had co-infection of both species. Moreover, 74.5% of the participants had prior knowledge about schistosomiasis with 67.0% of them how it is transmitted and 63.8% having no idea about the preventive measures. Three-quarters of the respondents considered schistosomiasis a serious disease while their practices to prevent infections were still inadequate, with only 34.7% of them seeking treatment from clinics/hospitals. Significant associations between the KAP and age, gender, education and employment status were reported. Multiple logistic regression analysis revealed that age, gender, history of infection and educational level of the respondents were the most important factors significantly associated with the KAP on schistosomiasis among this population.Schistosomiasis is still prevalent among Hausa communities in Nigeria and participants' knowledge about the disease was poor. Mass drug administration, community mobilization and health education regarding the cause, transmission and prevention of schistosomiasis
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
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
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.
A. M. Napon
Full Text Available Schistosomiasis presenting as an abdominal mass with chronic pain in a child is not common. This report presents case of child presenting with schistosomiasis presenting as an abdominal mass with chronic pain. Abdominal ultrasonography did not particularly contribute to definitive pre-operative diagnosis. However, pathological examination of surgical specimen confirmed Schistosoma mansoni eggs in the biospy. A decrease in the mass volume was noticed under medical treatment (Biltricide. The aim of this report was to intimate clinicians on possible abdominal schistosomiasis as differential diagnosis of childhood abdominal mass. This is a clarion call for a high index of suspicion of childhood abdominal schistosomiasis in children presenting with abdominal mass in a tropical setting.
Carmen Moreno Glasser
The program of schistosomiasis control for the State of São Paulo, where only low endemicity areas occur, is discussed in this paper. Inclusion of schistosomiasis among the diseases due to obligatory notification is considered as a measure of great importance. Accordingly the search for passive cases conducted by the public health system acquired major importance in the disease surveillance. As from 1981 to 1992 only 11% of the detected cases were considered as autochthonous. The main transmi...
Yang Guo-Jing; Sun Le-Ping; Hong Qing-Biao; Zhu Hong-Ru; Yang Kun; Gao Qi; Zhou Xiao-Nong
Abstract Background The application of chemical molluscicides is still one of the most effective measures for schistosomiasis control in P. R. China. By applying diverse molluscicide treatment scenarios on different snail densities in the field, we attempted to understand the cost-effectiveness of molluscicide application so as to prescribe an optimal management approach to control intermediate host snail Oncomelania hupensis under acceptable thresholds based on the goal of the National Schis...
Oliveira, Carolina R.; Rezende, Cíntia M. F.; Silva, Marina R.; Ana Paula Pêgo; Olga Borges; Alfredo M. Goes
BACKGROUND: Schistosomiasis is one of the most important neglected tropical diseases and an effective control is unlikely in the absence of improved sanitation and vaccination. A new approach of oral vaccination with alginate coated chitosan nanoparticles appears interesting because their great stability and the ease of target accessibility, besides of chitosan and alginate immunostimulatory properties. Here we propose a candidate vaccine based on the combination of chitosan-based nanoparticl...
Muhumuza, Simon; Olsen, Annette; Katahoire, Anne; Nuwaha, Fred
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 ...
Ndeffo Mbah, Martial L.; Poolman, Eric M.; Atkins, Katherine E.; Orenstein, Evan W.; Meyers, Lauren Ancel; Townsend, Jeffrey P.; Galvani, Alison P.
Background 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. Methods We developed a mathematical model of female genital schistosomiasis (FGS) and H...
Attwood Stephen W; Upatham E
Abstract Background The snail Neotricula aperta transmits Mekong schistosomiasis in southern Laos and Cambodia, with about 1.5 million people at risk of infection. Plans are under consideration for at least 12 hydroelectric power dams on the lower Mekong river and much controversy surrounds predictions of their environmental impacts. Unfortunately, there are almost no ecological data (such as long term population trend studies) available for N. aperta which could be used in impact assessment....
Han-qiu Liu; Xiao-yuan Feng; Zhen-wei Yao; Hua-ping Sun
Objective To describe the characteristic magnetic resonance imaging (MRI) appearance of cerebral schistosomiasis.Methods Twenty-five patients whose diagnosis of central nervous system (CNS) schistosomiasis had been pathologically (n=8) and clinically (n=17) confirmed were randomly selected.MRI was performed on a Signal 1.5T MRI scanner before and after the intravenous administration of gadopentetate dimeglumine constrast medium.We reviewed the MRI studies obtained at the time of initial presentation,as well as follow-up studies obtained during and after medical treatment.Results Immunological tests in 15 patients indicated schistosomiasis haematobium.Contrast-enhanced T1-weighted images in 22 cases showed central linear enhancement surrounded by multiple enhancing punctate nodules,which appeared "arborized".Through operation and pathological examination,8 cases had the granuloma formation of schistosomal eggs extensive surrounded by inflammation and venous congestion.And 17 cases were treated with praziquantel and corticosteroid therapy.And they were followed up for 2 months by taking MRI,which turned out to be complete resolution of the enhancing structure and edema.At follow-up,all the patients' initial symptoms also resolved.Conclusion The specified MRI enhancement pattern of cerebral schistosomiasis is common in most cases of CNS schistosomiasis,so it should be taken account into the diagnosis of cerebral schistosomiasis.
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.
Full Text Available The molluscicidal activity of the bark of Entada phaseoloides and extracts from tubers of its related specie, Entada parvifolia against Oncomelania quadrasi, the snail intermediate host of Shistosoma japonicum in the Philippines were determined.The commercial gogo bark applied to waters with O. quadrasi, in the proportion of 2 gms/liter will kill 100% of snails within 24 hours. At this concentration miracidia and cercariae of S. japonicum in the same waters will die within one hour, thus, making the water safe or noninfective for some time. At the dose 100 gms/sqm of water-covered terrestial snail habitats, provided previously cleared of vegetations, at least 90% of O. quadrasi will die within 24 hours. These measures can be practical on a self-help basis by inhabitants of schistosomiasis endemic areas where gogo plant grows or where its bark is marketed.At dilution of 1:5,000 saponin extracted from tubers of E. parvifolia killed at least 90% of snails after 24 hours exposure while ethanol (crude saponin and other extracts require at least 1:2,000 concentration to kill at least 90% of O. quadrasi. At these concentrations and the expenses and time involved in the preparation of these extracts, they are not economical or practical for large scale use of molluscicides.It is suggested that methods of extraction and purification which require little time of preparation and a cheaper but of higher recovery rate of molluscicidal principles be developed.Surveys of barrios in three towns of Leyte, endemic for Schistosomiasis japonica using the circum oval-precipitin test (COPT and stool examination in the same subjects were undertaken. Findings show that the use of blood COPT method is advantageous over that of the stool examination in schistosomiasis surveys as its prescribed procedure is simple, specific and more sensitive. Moreover, the prevalence rate it determined was higher than that obtained by the stool examination in all three towns studied with
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.
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)
... Animal and Plant Health Inspection Service 9 CFR Part 77 Approved Tests for Bovine Tuberculosis in... of antibodies to bovine tuberculosis in certain species of captive cervids. This action is necessary..., CO 80526-8117; (970) 494-7378. SUPPLEMENTARY INFORMATION: Background Bovine tuberculosis is...
Ketema Deribew; Zinaye Tekeste; Beyene Petros
Objective: To assess the prevalence of anemia in children with urinary schistosomiasis, malaria and concurrent infections by the two diseases. Methods: Urine and blood samples were collected from 387 children (216 males and 171 females) to examine urinary schistosomiasis and malaria and to determine hemoglobin concentration at Hassoba and Hassoba Buri village in Amibara woreda, Afar region, Ethiopia. Results: The overall prevalence of urinary schistosomiasis and Plasmodium falciparum malaria was 24.54% and 6.20% respectively. Only 2.84% of children carried concurrent infections of both parasites. There was high percentage of anemic patients (81.81%) in the coinfected cases than in either malaria (33.3%) or schistosomiasis (38.94%) cases. There was significantly low mean hemoglobin concentration in concurrently infected children than non-infected and single infected (P0.05). The level of hemoglobin was negatively correlated with the number of S. haematobium eggs/10 mL urine (r=-0.6) and malaria parasitemia (r=-0.53). Conclusions: The study showed that anemia is higher in concurrently infected children than non-infected and single infected. Furthermore, level of hemoglobin was negatively correlated with the number of S. haematobium eggs and malaria parsitemia. Therefore, examination of hemoglobin status in patients co-infected with malaria and schistosomiasis is important to reduce the risk of anemia and to improve health of the community.
Gray, Darren J; Li, Yue-Sheng; Williams, Gail M; Zhao, Zheng-Yuan; Harn, Donald A; Li, Sheng-Ming; Ren, Mao-Yuan; Feng, Zeng; Guo, Feng-Ying; Guo, Jia-Gang; Zhou, Jie; Dong, Yu-Lan; Li, Yuan; Ross, Allen G; McManus, Donald P
Despite major successes in its control over the past 50years, schistosomiasis japonica continues to be a public health problem in the People's Republic of China (P.R. China). Historically, the major endemic foci occur in the lakes and marshlands along the Yangtze River, areas where transmission interruption has proven difficult. The current endemic situation may alter due to the closure of the Three Gorges Dam. Considerable environmental and ecological changes are anticipated that may result in new habitats for the oncomelanid intermediate snail host of Schistosoma japonicum (Sj), thereby increasing the risk of transmission. The current national control program for P.R. China involves a multi-component integrated strategy but, despite targeting multiple transmission pathways, certain challenges remain. As the Chinese government pushes towards elimination, there is a requirement for additional tools, such as vaccination, for long-term prevention. Whereas the zoonotic nature of schistosomiasis japonica adds to the complexity of control, it provides a unique opportunity to develop a transmission blocking vaccine targeting bovines to assist in the prevention of human infection and disease. Mathematical modelling has shown that control options targeting the various transmission pathways of schistosomiasis japonica and incorporating bovine vaccination, mass human chemotherapy and mollusciciding could lead to its elimination from P.R. China. Here we present the study design and baseline results of a four-year cluster randomised intervention trial we are undertaking around the schistosomiasis-endemic Dongting Lake in Hunan Province aimed at determining the impact on schistosome transmission of the multi-component integrated control strategy, including bovine vaccination using a heterologous "prime-boost" delivery platform based on the previously tested SjCTPI vaccine. PMID:24929133
Xu, Xiao-Lin; Zhu, Rong; Zhang, Li-Juan; Guo, Jia-Gang
Schistosomiasis is a tropical disease, which could do serious damage to the people's health, and it hinders the development of the social economy but may be neglected. After a positive control, some countries and regions have blocked the spread of schistosomiasis. However, in the past few years, with the development of social economy, due to the global movement of people, schistosomiasis not only poses a threat to control areas, but also may cause new endemic areas. This article reviews the parasitological characteristics, clinical manifestations, epidemiological situation, and control approaches of three major kinds of human schistosomiasis, schistosomiasis japonica, schistosomiasis haematobia, and schistosomiasis mansoni. PMID:24024456
Sandra Costa Drummond
Full Text Available Introduction This study aimed to evaluate whether a low platelet count is a good surrogate marker of hepatosplenic schistosomiasis (HSS in a rural area of Brazil. A small district in southeastern Brazil, with a population of 1,543 individuals and a 23% prevalence of schistosomiasis, was selected for this investigation. Methods In July 2012, 384 volunteers were subjected to clinical, ultrasonography (US, and laboratory examinations, including stool sample analysis. The HSS patients were classified into four groups: Group 1 consisted of patients with a spleen >13cm and liver fibrosis; Group 2 consisted of patients with a palpable spleen and spleen>13cm measured by US; Group 3 consisted of patients with a spleen >13cm measured by US; and Group 4 consisted of patients with a palpable spleen. Results Eight patients were in Group 1 (2.1%, twenty-one were in Group 2 (5.5%, eight were in Group 3 (2.1%, and eighteen were in Group 4 (4.7%. A significant difference in the mean platelet counts was observed between the patients with and without HSS (p<0.01. Based on the receiver operating characteristic (ROC curve (platelet count <143,000/mm3, the sensitivity was greater than 92% in all groups, and the specificity varied from 44.4% to 75%. Conclusions We concluded that in endemic areas, thrombocytopenia demonstrates good sensitivity for detecting HSS and may be used as a screening tool to identify patients with HSS.
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....... IL-8 levels were higher in S. mansoni-infected individuals. Treatment for schistosomiasis caused a decrease in levels of sTNF-rII (P < 0.05) and IL-10 (P < 0.001). Our results indicate that schistosomiasis treatment may attenuate HIV replication by decreasing systemic inflammation Udgivelsesdato...... (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...
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.
Full Text Available For many years the epidemiological significance of immunity in human schistosomiasis has been the subject of inconclusive debate. Recently, the results of studies from Brazil and Kenya, on Shistosoma mansoni and from Zimbabwe and The Gambia on S. haematobium have confirmed the importance of protective immunity. In communities in endemic areas the development of immunity to infection only occurs after many years of exposure. In part this due to the slow development of antibodies wich are protective but also to the earlier development of antibody isotypes which lack protective capacity and wich are capable of interfering with the functioning of protective antibodies. Protective antibodies appear to be of the IgE class but some IgG subclasses may be also be important. Initially, blocking antibodies were thought to be predominantly IgM and IgG2 but IgG4 also seems to posses blocking activity. The early production of blocking antibodies and late production of protective antibodies may be indicative of cytokine induced immunoglobulin class swiching caused by the sequential involvment of different lymphokines.
He, Ping; Song, Lan-Gui; Xie, Hui; Liang, Jin-Yi; Yuan, Dong-Ya; Wu, Zhong-Dao; Lv, Zhi-Yue
Schistosomiasis is an important zoonotic parasitic disease that causes serious harms to humans and animals. Surveillance and diagnosis play key roles in schistosomiasis control, however, current techniques for surveillance and diagnosis of the disease have limitations. As genome data for parasites are increasing, novel techniques for detection incorporating nucleotide sequences are receiving widespread attention. These sensitive, specific, and rapid detection methods are particularly important in the diagnosis of low-grade and early infections, and may prove to have clinical significance. This paper reviews the progress of nucleic acid detection in the diagnosis and prevention of schistosomiasis, including such aspects as the selection of target genes, and development and application of nucleic acid detection methods. PMID:27025210
Maria Angelina C Miranda
Full Text Available Portal hypertension is a frequent complication of chronic liver disease, detected not only in schistosomiasis, but also in cirrhosis of any etiology. Vascular alterations in the colonic mucosa are a potential source for acute or chronic bleeding and have been observed in patients with portal hypertension. The purpose of this prospective study was to describe and propose a classification for the vascular alterations of portal hypertension in the colonic mucosa among patients with hepatosplenic schistosomiasis mansoni. One or more alterations of portal colopathy were observed in all patients and they were classified according to their intensity, obeying the classification proposed by the authors. Portal colopathy is an important finding in hepatosplenic schistosomiasis and might be the cause of lower gastrointestinal bleeding in patients with severe portal hypertension.
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
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.
Richardson, Sharise T; Franklin, Ashley L; Rome, Ellen S; Simms-Cendan, Judith S
Urogenital schistosomiasis affects millions of women in sub-Saharan Africa. Infection by the causative organism, Schistosoma hematobium, commonly occurs during childhood and adolescence and can lead to anemia from hematuria, inflammation on the cervix which can increase risk of HIV transmission, and pelvic infection leading to infertility. Fortunately treatment is not costly, but early diagnosis is important to reduce long-term morbidity. Our objective is to review the epidemiology, pathophysiology, and diagnosis of urogenital schistosomiasis as well as treatment to improve the reproductive health of girls where this infection is endemic. PMID:26173381
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
Full Text Available Background: Urinary schistosomiasis is endemic in Nigeria and continues to pose public health challenges especially in inhabitants of rural areas. 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 to determine presence of Schistosoma haematobium eggs in urine. Questionnaires were also administered to children to collect information on socio-demographic data and water-contact activities. Results: An overall prevalence of 41.5% was observed among the 1,124 children examined. Secondary school children recorded higher prevalence rate than primary school children and pre-school children. A significant difference in prevalence was observed between the three categories of children examined. Males had statistically higher prevalence rate than females. No significant difference was observed between the different age groups, and across the months. Children whose parents have no formal education and whose parents have primary education recorded the highest prevalence with statistical significance. Children whose parents’ occupation is farming had the highest prevalence which was statistically significant compared to those whose parents were non-farmers. Children who played/bathed and collected fresh water snails had higher risks of infection with urinary schistosomiasis in the area. Conclusion: The study draws attention to the health hazards posed by urinary schistosomiasis among children in in the studied area. The urgent need for a decisive control intervention to stem this problem cannot be overemphasized.
Akram M Abou-Zied
Full Text Available Background: Schistosomiasis is an infection caused by blood flukes of the genus Schistosoma. Schistosomes are successful parasites, apparently as a result of prolonged co-evolution with their hosts. Studies done nationwide in Egypt found the highest risk of hepatitis C virus (HCV co-infection is in those infested with schistosome without history of blood transfusions. However, the association between schistosomiasis and HCV infection is incompletely understood. Aims: The overall aim of this study was to assess whether or not a genomic association between schistosomal infestation and HCV infection exists. Materials and Methods: Oligonucleotide specific primers of HCV-polymerase chain reaction (PCR diagnostics were used to screen the genomic DNA and cDNA library pool of Schistosoma mansoni as templates based on the end-point PCR approach. Results: Screening of schistosome DNA by PCR, lead to the detection of sequences similar to HCV. PCR products were obtained when adult worms genomic DNA were used as templates while no PCR products were amplified from S. mansoni λZAPII cDNA library pool. The resulting PCR products were sequenced and compared with the other closely related HCV sequence database at the website . Conclusions: This work demonstrates the existence of HCV and its replication in the genomic DNA of S. mansoni. In addition, it highlights the fact that the parasite can carry the virus genome and therefore, is considered as a nonhuman vector for the transmission of HCV infections.
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
Fulton, R W; Downing, M M; Cummins, J M
The antiviral effects of bovine interferons on the replication of bovine respiratory tract viruses were studied. Bovine turbinate monolayer cultures were treated with bovine interferons and challenged with several bovine herpesvirus 1 strains, bovine viral diarrhea virus, parainfluenza type 3 virus, goat respiratory syncytial virus, bovine respiratory syncytial virus, bovine adenovirus type 7, or vesicular stomatitis virus. Treatment with bovine interferons reduced viral yield for each of the...
@@To investigate the effects of immunotoxin (bio-missile) on the prevention of schistosomiasis. The monoclonal antibody NP11-4, located in out-layer membrane of adult worm, membrane of cercariae, membrane of schistosomula, shell of egg and membrane of miracidium in egg, was combined with artesunate (produced by Guilin Pharmaceutical Factory of China) by chemical method to fabricate immunotoxin.
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.
Ketema; Deribew; Zinaye; Tekeste; Beyene; Petros
Objective:To assess the prevalence of anemia in children with urinary schistosomiasis,malaria and concurrent infections by the two diseases.Methods:Urine and blood samples were collected from 387 children(216 males and 171 females)to examine urinary schistosomiasis and malaria and to determine hemoglobin concentration at Hassoba and Hassoba Buri village in Amibara woreda,Afar region,Ethiopia.Results:The overall prevalence of urinary schistosomiasis and Plasmodium falciparum malaria was 24.54%and 6.20%respectively.Only 2.84%of children carried concurrent infections of both parasites.There was high percentage of anemic patients(81.81%)in the coinfected cases than in either malaria(33.3%)or schistosomiasis(38.94%)cases.There was significantly low mean hemoglobin concentration in concurrently infected children than non-infected and single infected(P<0.05).The mean hemoglobin concentration between Plasmodium falciparum and S.haematobium infected children showed no significant difference(P>0.05).The level of hemoglobin was negatively correlated with the number of S.haematobium eggs/10 mL urine(r=-0.6)and malaria parasitemia(r=-0.53).Conclusions:The study showed that anemia is higher in concurrently infected children than non-infected and single infected.Furthermore,level of hemoglobin was negatively correlated with the number of S.haematobium eggs and malaria parsitemia.Therefore,examination of hemoglobin status in patients co-infected with malaria and schistosomiasis is important to reduce the risk of anemia and to improve health of the community.
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. PMID:25636189
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....... IL-8 levels were higher in S. mansoni-infected individuals. Treatment for schistosomiasis caused a decrease in levels of sTNF-rII (P < 0.05) and IL-10 (P < 0.001). Our results indicate that schistosomiasis treatment may attenuate HIV replication by decreasing systemic inflammation....... (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...
Kamel, M I; Moustafa, Y A; Foda, N; Khashab, S; Moemen, M; Abo el-Naga, R M
The effect of schistosomiasis on quality of life (QOL) and productivity of workers was examined. In a textile factory in Alexandria, Egypt, personal, occupational and sociodemographic data were collected from 172 workers with schistosomiasis and 172 workers without schistosomiasis. Several indicators of productivity and the World Health Organization QOL brief were used to determine the impact of schistosomiasis. The disease affected the general, physical and independence, psychological and spiritual, and social domains of QOL. Although the productivity score of workers with schistosomiasis did not differ significantly from the control group, they had significantly lower additional hours of work and lower total incentives/month. A significant relationship was found between severity of schistosomiasis and QOL domains and productivity indicators. PMID:15339125
Qiu Chunhui; Liu Shengfa; Hong Yang; Fu Zhiqiang; Wei Meimei; Ai Dezhou; Lin Jiaojiao
Abstract Background Thyroid hormones (TH) modulate growth, development and differentiation and metabolic processes by interacting with thyroid hormone receptors (THRs). The purpose of this study was to identify a novel thyroid hormone receptor beta encoding gene of Schistosoma japonicum (SjTHRβ) and to investigate its potential as a vaccine candidate antigen against schistosomiasis in BALB/c mice. Methods The full-length cDNA sequence of SjTHRβ, its gene organization, and its transcript level...
Anbalagan Sankarappan; Balachandran Chellapandian; Arun Prasanna Vimalanathan; Kannan Mani; Dinakaran Sundaram; Krishnan Muthukalingan
Background & objectives: Vector ecology and taxonomy of snails is a prerequisite for controlling schistosomiasis in the tropics. The ecology of the freshwater limpet genus Ferrissia was investigated for detection of cercariae larvae in them, and taxonomic description of a new species of the genus Ferrissia. Methods: This study was conducted in 15 perennial streams from five different hills of south India. To study the seasonal patterns, a stream from each hill was selected and sampled in t...
Zhao Qin-Ping; Guo Yi; Dong Hui-Fen; Liu Rong; Jiang Ming-Sen
Abstract Background Praziquantel has been used as first-line drug for chemotherapy of schistosomiasis since 1984. Besides praziquantel, artemether and artesunate have also been used for the control of this infectious disease since late 1990s. In this article, we conducted a systematic review and meta-analysis to evaluate the antischistosomal efficacy of different medication strategies including monotherapy or combination therapies of these drugs. Results A number of 52 trials from 38 articles...
Julie Balen; Zhao-Chun Liu; McManus, Donald P.; Giovanna Raso; Jürg Utzinger; Shui-Yuan Xiao; Dong-Bao Yu; Zheng-Yuan Zhao; Yue-Sheng Li
BACKGROUND: 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 equitab...
Olajide, Abimbola Olaniyi; Olajide, Folakemi Olajumoke; Aremu, Ademola Adegoke; Komolafe, Akinkunmi Oluwole
Schistosomiasis is one of the oldest and commonest parasitic infestations of mankind and one of the leading infestations of public health concern. Hitherto, praziquantel has been the only drug for mass eradication of Schistosomiasis. Few reports have shown possible resistance of the schistosome to praziquantel in some part of the world with global concern about the future of the drug. We report this case to illustrate progression of Schistosomiasis to surgical complication despite treatment, ...
AIM:To explore the interventional effects and mechanism of in vitro cultivated Calculus Bovis compound preparation(ICCBco) on pulmonary lesions in portal hypertensive rabbits with schistosomiasis. METHODS:The experimental group included 20 portal hypertensive rabbits with schistosomiasis treated by ICCBco.The control group included 20 portal hypertensive rabbits with schistosomiasis treated by praziquantel. The morphological changes of the pulmonary tissues were observed under light and electron microscopy....
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....... METHODS: A literature search on T. solium taeniosis/cysticercosis was performed to compile all known studies on the presence of T. solium and apparent prevalence of taeniosis and porcine cysticercosis in Africa. Studies were geo-referenced using an online gazetteer. A Bayesian framework was used...... 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...
Abo-Salem, Elsayed S.; Ramadan, Mahmoud M.
Patient: Male, 55 Final Diagnosis: Thrombosed pulmonary artery aneurysm Symptoms: Cough productive • fever • shortness of breath Medication: — Clinical Procedure: Pericardiocentesis Specialty: Cardiology Objective: Rare disease Background: We herein report a case of huge pulmonary artery aneurysm in a 55-year-old male farmer from the Nile delta (Lower-Egypt), mostly due to infestation with Schistosoma mansoni, which is the parasite causing hepatosplenic schistosomiasis. Case Report: This male patient was admitted with a month-long history of progressive shortness of breath, 2-month history of fever, and a cough with mucoid sputum for 10 days. On examination, he had normal temperature and blood pressure, but he had tachypnea, tachycardia, and congested neck veins. Electrocardiography showed multifocal atrial tachycardia and right bundle branch block. Conclusions: The present case is unique in that it shows the presence of a huge pulmonary artery aneurysm despite the absence of pulmonary hypertension. PMID:25746428
Carmen Moreno Glasser
Full Text Available The program of schistosomiasis control for the State of São Paulo, where only low endemicity areas occur, is discussed in this paper. Inclusion of schistosomiasis among the diseases due to obligatory notification is considered as a measure of great importance. Accordingly the search for passive cases conducted by the public health system acquired major importance in the disease surveillance. As from 1981 to 1992 only 11% of the detected cases were considered as autochthonous. The main transmission areas are located at the Litoral and Paraiba Valley regions. In the period of time under analysis, the epidemiological surveillance data suggest a decrease in the morbidity and in the autochthony tendency in the State of São Paulo.
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.
Martins, R D; Borges, D R
AIMS: To evaluate serum gamma glutamyltransferase (GGT) activity in a group of non-alcoholic patients with the hepatointestinal form of schistosomiasis; and the response of both GGT and alkaline phosphatase to an ethanol challenge in two subgroups of patients with different baseline serum concentrations of GGT. METHODS: Seventy six non-alcoholic, non-smoking hepatitis B virus (HBV) negative men with normal body mass index, who denied blood product transfusion or use of medication, were studie...
Paulo Marcos Z. Coelho; Jurberg, Arnon D.; Oliveira, Áureo A.; Naftale Katz
The development of novel methods for parasitological diagnosis that are both highly sensitive and low in cost has been strongly recommended by the World Health Organization. In this study, a new technique for diagnosis of schistosomiasis mansoni is proposed based on the differential sedimentation of eggs when subjected to a slow continuous flux of 3% saline solution through a porous plaque. This influx suspends low-density faecal material, effectively cleaning the sample. The remaining sedime...
Enk, Martin Johannes; Amaral, Graciela Larissa; Costa e Silva, Matheus Fernandes; Silveira-Lemos, Denise; Teixeira-Carvalho, Andréa; Martins-Filho, Olindo Assis; Correa-Oliveira, Rodrigo; Gazinnelli, Giovanni; Coelho, Paulo Marcos Zech; Massara, Cristiano Lara
This paper reports an outbreak of acute schistosomiasis among 38 tourists who rented a country house in the district of Igarapé, the metropolitan region of Belo Horizonte, Brazil, during a holiday period in 2006. A total number of 32 individuals were positive for Schistosoma mansoni. Results of stool examinations revealed individual S. mansoni egg counts per gram of faeces (epg) ranging from 4-768 epg with a geometric mean egg count of 45. The most frequent clinical symptoms were abdominal pain (78.1%), headache (75%), fever (65.6%), dry cough (65.2%) and both diarrhoea and asthenia (59.4%). A malacological survey of the area, where 22 specimens of Biomphalaria glabrata were collected, revealed three (13.6%) specimens eliminating Schistosoma cercariae. This investigation re-confirms a recently described pattern of schistosomiasis infection, resulting in the acute form of the disease and connected to rural tourism, which contributes to the spread of the disease among the middle-class and into non-endemic areas. The lack of specific knowledge about acute schistosomiasis among health services causes an increased number of unnecessary diagnostic procedures and delays in accurate diagnosis and treatment, resulting in considerable discomfort for the patients. PMID:20721505
Martin Johannes Enk
Full Text Available This paper reports an outbreak of acute schistosomiasis among 38 tourists who rented a country house in the district of Igarapé, the metropolitan region of Belo Horizonte, Brazil, during a holiday period in 2006. A total number of 32 individuals were positive for Schistosoma mansoni. Results of stool examinations revealed individual S. mansoni egg counts per gram of faeces (epg ranging from 4-768 epg with a geometric mean egg count of 45. The most frequent clinical symptoms were abdominal pain (78.1%, headache (75%, fever (65.6%, dry cough (65.2% and both diarrhoea and asthenia (59.4%. A malacological survey of the area, where 22 specimens of Biomphalaria glabrata were collected, revealed three (13.6% specimens eliminating Schistosoma cercariae. This investigation re-confirms a recently described pattern of schistosomiasis infection, resulting in the acute form of the disease and connected to rural tourism, which contributes to the spread of the disease among the middle-class and into non-endemic areas. The lack of specific knowledge about acute schistosomiasis among health services causes an increased number of unnecessary diagnostic procedures and delays in accurate diagnosis and treatment, resulting in considerable discomfort for the patients.
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
Full Text Available BACKGROUND: Appropriate diagnostics to monitor disease trends and assess the effectiveness and impact of interventions are essential for guiding treatment strategies at different thresholds of schistosomiasis transmission and for certifying elimination. Field validation of these assays is urgently needed before they can be adopted to support policy decisions of the national programme for control and elimination of schistosomiasis in P.R. China. We compared the efficacy and utility of different immunoassays in guiding control strategies and monitoring the endemic status of S. japonicum infections towards elimination. METHODOLOGY/PRINCIPAL FINDINGS: A cross-sectional survey was conducted in seven villages with different transmission intensities settings to assess the performance and utility of three immunoassays, e.g., an indirect hemagglutination assay (IHA_JX, an enzyme linked immunosorbent assay (ELISA_SZ, and a dot immunogold filtration assay (DIGFA_SH. 6,248 individuals aged 6-65 years old who gave consent and supplied their stool and blood samples were included for data analysis. Results showed that ELISA_SZ performed significantly higher sensitivity (95.45%, 95%CI: 92.94-97.97% than IHA_JX (87.59%, 95%CI: 83.51-91.49% and DIGFA_SH (79.55%, 95%CI: 74.68-84.41%, especially in subgroups with very low infection intensity. The specificity of ELISA_SZ, IHA_JX, DIGFA_SH in 6-9 year olds with occasional exposure was nearly 90%. DIGFA_SH performed the highest screening efficacy for patients among three assays with overall positive predicative value of 13.07% (95%CI: 11.42-14.72%. We found a positive correlation of antibody positive rate of IHA_JX with results of stool examination in age strata (r = 0.70, P<0.001. Seropositivity of IHA_JX in children aged 6-9 years old showed an excellent correlation with prevalence of schistosome infection in the seven communities (r = 0.77, P<0.05. CONCLUSIONS/SIGNIFICANCE: Studies suggest that ELISA
... RIN 0579-AC68 Bovine Spongiform Encephalopathy; Importation of Bovines and Bovine Products AGENCY... live bovines and products derived from bovines with regard to bovine spongiform encephalopathy. This.... SUPPLEMENTARY INFORMATION: On March 16, 2012, we published in the Federal Register (77 FR 15848-15913, Docket...
Cercariae of the Chinese mainland strain of Schistosoma japonicum were used. Eighteen cattle, divided into six groups of three each, were immunized with schistosomula transformed from cercariae exposed to three different doses of X-irradiation (24, 36, and 48 kR). The immunization was given either once, twice, or thrice, and the number of immunizing schistosomula was 10,000 or more in each immunization. The immunized cattle were challenged with 500 normal cercariae. Five native cattle were similarly infected with normal cercariae as controls. All cattle were killed 32-33 days after challenge or infection, and the worms were obtained by perfusion. The mean worm reduction in the 18 experimental animals varied from 42.1 to 96.0%. The mean percent worm reduction of the six experimental groups varied from 54.8 to 87.1. The reduction was greater with increasing numbers of immunizations, and was higher in the groups immunized with schistosomula exposed to 36 kR than in those exposed to 24 or 48 kR. Statistical analyses showed that all immunized groups yielded significantly fewer worms than controls. However, the three doses of X-irradiation (24, 36, and 48 kR) had no significant effect for a fixed number of immunizations (1, 2, or 3). The means for both two and three immunizations were significantly different from the mean for one immunization, although they were not significantly different from each other
Hsue, S.Y.; Hsue, H.F.; Xu, S.T.; Shi, F.H.; He, Y.X.; Clarke, W.R.; Johnson, S.C.
Cercariae of the Chinese mainland strain of Schistosoma japonicum were used. Eighteen cattle, divided into six groups of three each, were immunized with schistosomula transformed from cercariae exposed to three different doses of X-irradiation (24, 36, and 48 kR). The immunization was given either once, twice, or thrice, and the number of immunizing schistosomula was 10,000 or more in each immunization. The immunized cattle were challenged with 500 normal cercariae. Five native cattle were similarly infected with normal cercariae as controls. All cattle were killed 32-33 days after challenge or infection, and the worms were obtained by perfusion. The mean worm reduction in the 18 experimental animals varied from 42.1 to 96.0%. The mean percent worm reduction of the six experimental groups varied from 54.8 to 87.1. The reduction was greater with increasing numbers of immunizations, and was higher in the groups immunized with schistosomula exposed to 36 kR than in those exposed to 24 or 48 kR. Statistical analyses showed that all immunized groups yielded significantly fewer worms than controls. However, the three doses of X-irradiation (24, 36, and 48 kR) had no significant effect for a fixed number of immunizations (1, 2, or 3). The means for both two and three immunizations were significantly different from the mean for one immunization, although they were not significantly different from each other.
Muhumuza, Simon; Olsen, Annette; Katahoire, Anne; Kiragga, Agnes N.; Nuwaha, Fred
Background:School-based mass treatment with praziquantel is the cornerstone for schistosomiasis control in school-aged children. However, uptake of treatment among school-age children in Uganda is low in some areas. The objective of the study was to examine the effectiveness of a pre-treatment sn......Background:School-based mass treatment with praziquantel is the cornerstone for schistosomiasis control in school-aged children. However, uptake of treatment among school-age children in Uganda is low in some areas. The objective of the study was to examine the effectiveness of a pre...... 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 = 0.002). The...
Full Text Available Abstract Background The application of chemical molluscicides is still one of the most effective measures for schistosomiasis control in P. R. China. By applying diverse molluscicide treatment scenarios on different snail densities in the field, we attempted to understand the cost-effectiveness of molluscicide application so as to prescribe an optimal management approach to control intermediate host snail Oncomelania hupensis under acceptable thresholds based on the goal of the National Schistosomiasis Control Programme. Methods The molluscicidal field trial was carried out in the marshland of an island along the Yangtze River, Jiangsu province, P.R. China in October 2010. Three plots in the island representing low-density, medium-density and high-density groups were identified after the baseline survey on snail density. Each snail density plot was divided into four experimental units in which molluscicide (50% niclosamide ethanolamine salt wettable powder was applied once, twice, trice and four times, respectively. The logistic regression model to correlate snail mortality rate with the covariates of number of molluscicidal treatment and snail density, and a linear regression model to investigate the relationship between cost-effectiveness and number of molluscicidal treatment as well as snail density were established. Results The study revealed that increase in the number of molluscicide treatments led to increased snail mortality across all three population density groups. The most cost-effective regimen was seen in the high snail density group with a single molluscicide treatment. For both high and low density groups, the more times molluscicide were applied, the less cost-effectiveness was. However, for the median density group, the level of cost-effectiveness for two applications was slightly higher than that in one time. Conclusions We concluded that different stages of the national schistosomiasis control/elimination programme, namely
Martial L Ndeffo Mbah
Full Text Available BACKGROUND: 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. METHODS: 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. FINDINGS: 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. CONCLUSIONS: 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
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.
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.
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 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
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
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.
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.
Full Text Available Abstract Background Human resistance to re-infection with S. mansoni is correlated with high levels of anti-soluble adult worm antigens (SWAP IgE. Although it has been shown that IL-4 and IL-5 are crucial in establishing IgE responses in vitro, the active in vivo production of these cytokines by T cells, and the degree of polarization of Th2 vs. Th0 in human schistosomiasis is not known. To address this question, we determined the frequency of IL-4 and IFN-γ or IL-5 and IL-2 producing lymphocytes from schistosomiasis patients with high or low levels of IgE anti-SWAP. Results Our analysis showed that high and low IgE-producers responded equally to schistosomiasis antigens as determined by proliferation. Moreover, patients from both groups displayed similar percentages of circulating lymphocytes. However, high IgE-producers had an increased percentage of activated CD4+ T cells as compared to the low IgE-producers. Moreover, intracellular cytokine analysis, after short-term stimulation with anti-CD3/CD28 mAbs, showed that IgE high-producers display an increase in the percentage of T lymphocytes expressing IL-4 and IL-5 as compared to IgE low-responders. A coordinate control of the frequency of IL-4 and IL-5 producing lymphocytes in IgE high, but not IgE low-responders, was observed. Conclusions High IgE phenotype human schistosomiasis patients exhibit a coordinate regulation of IL-4 and IL-5 producing cells and the lymphocyte derived IL-4 comes from true polarized Th2 like cells, in the absence of measurable Th0 cells as measured by co-production of IL-4 and IFN-γ.
José Carlos Sousa-Figueiredo
Full Text Available BACKGROUND: The World Health Organization now recommends the provision of praziquantel treatment to preschool-aged children infected with schistosomiasis. For intestinal schistosomiasis the current operational field diagnostic standard is examination of a thick Kato-Katz smear by microscopy prepared from a single stool specimen, and although pragmatic, this methodology has well-known shortcomings. Here, as a potential alternative, the performance of the urine circulating cathodic antigen (CCA dipstick test was assessed in terms of disease-mapping and point-of-care diagnosis for intestinal schistosomiasis in preschool-aged children. Our manuscript reports on findings at baseline and at the end of a one-year longitudinal treatment study. METHODOLOGY/PRINCIPAL FINDINGS: A total of 925 children (mean age 2.8 years were initially recruited from six lakeshore villages representative of high, moderate and low levels of disease transmission. At baseline, all children were tested for intestinal schistosomiasis by microscopic examination of duplicate Kato-Katz smears prepared from a single stool faecal, by antigen detection with the urine CCA dipstick test and by serology with a commercially available ELISA test (as 'gold-standard' that measures host antibody titres to soluble egg antigens. As a point-of-care diagnosis, the urine CCA dipstick test achieved sensitivity and specificity values ranging from 52.5-63.2% and 57.7-75.6%, respectively, with faecal microscopy achieving very high specificities (>87% but sensitivities as low as 16.7% in the low transmission setting. CONCLUSION/SIGNIFICANCE: The urine CCA test was shown to be more effective than faecal microscopy especially in lower transmission settings. The diagnostic performance of this test was not significantly impacted by treatment history or co-infections with other intestinal helminths.
J. Massoud; F.Arfaa; I. Farahmandian; A Ardalan; Mansoorian, A.
A combination of chemotherapy and mollusciciding has been used in Khuzestan, south-west Iran, since 1966, to try to control urinary schistosomiasis. The total amount of molluscicide used each year varied between 702 and 3505 kg and between 287 and 1320 infected persons were detected and treated annually. The prevalence of infection has gradually declined from 8.3% in 1970 to 0.7% in 1979. Similarly, the incidence of infection among schoolchildren decreased from 3.5% in 1970 to 0.7% in 1979. T...
Leonardo C Queiroz; Sandra C Drummond; De Matos, Maria Laura M; Mariana BS Paiva; Thaís S Batista; Ahraby ZM Kansaon; Carlos Maurício F. Antunes; José Roberto Lambertucci
The efficacy of oral praziquantel in the treatment of schistosomiasis has been considered low by most public health institutions. In this paper, we compared the efficacy of two dosages of praziquantel (80 mg/kg vs. 50 mg/kg) in patients with chronic schistosomiasis mansoni. Two hundred eighty-eight patients with schistosomiasis from a community in Brazil were randomly divided into two groups: 145 patients (Group 1) received 80 mg/kg body weight of oral praziquantel divided in two equal doses ...
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.
...; ] DEPARTMENT OF AGRICULTURE Animal and Plant Health Inspection Service 9 CFR Part 93 RIN 0579-AC68 Bovine Spongiform Encephalopathy; Importation of Bovines and Bovine Products Correction In proposed rule...
... Health Inspection Service 9 CFR Parts 92, 93, 94, 95, 96, and 98 RIN 0579-AC68 Bovine Spongiform Encephalopathy; Importation of Bovines and Bovine Products Corrections In rule document 2013-28228 appearing...
In the present study, attempts were made to classify the ultrasonic patterns of the liver infected with Schistosoma Japonicum. The calcification and fibrosis of the liver were evaluated by comparative investigation with an ultrasonogram and computed tomography (CT). Schistosomiasis Japonica was examined in 23 patients who were more than 45 years of age. It was diagnosed by liver needle biopsy, an intracutaneous test, or autopsy. The cases with a fish scale and network pattern had attenuation of the liver on ultrasonography and were unspecific on CT. Histological findings demonstrated moderate liver fibrosis. The cases with a sieve pattern had attenuation on ultrasonography, and the CT disclosed a retractive liver and the CT number of that liver was increased. Histological findings demonstrated a severe fibrotic liver. The cases with a mottled pattern had increased reflective spotty echo with an acoustic shadow, and the CT disclosed calcification. The histological findings demonstrated a marked calcification of the eggs. The cases with a mixed pattern, which consisted of mottled and sieve based on fish scale and network, had no retraction with less increase in the CT number. These results suggest that the peculiar reflective echo pattern of Schistosomiasis Japonica was due to not only calcification but also fibrosis of the liver. (author)
Background Cattle are important agriculturally and relevant as a model organism. Previously described genetic and radiation hybrid (RH) maps of the bovine genome have been used to identify genomic regions and genes affecting specific traits. Application of these maps to identify influential geneti...
The draft genome sequence of cattle (Bos taurus) has now been analyzed by the Bovine Genome Sequencing and Analysis Consortium and the Bovine HapMap Consortium, which together represent an extensive collaboration involving more than 300 scientists from 25 different countries. ...
Langholm Jensen, Jesper; Mølgaard, Anne; Navarro Poulsen, Jens Christian;
Bovine and camel chymosin are aspartic peptidases that are used industrially in cheese production. They cleave the Phe105-Met106 bond of the milk protein κ-casein, releasing its predominantly negatively charged C-terminus, which leads to the separation of the milk into curds and whey. Despite...... having 85% sequence identity, camel chymosin shows a 70% higher milk-clotting activity than bovine chymosin towards bovine milk. The activities, structures, thermal stabilities and glycosylation patterns of bovine and camel chymosin obtained by fermentation in Aspergillus niger have been examined...... interactions arising from variation in the surface charges and the greater malleability both in domain movements and substrate binding contribute to the better milk-clotting activity of camel chymosin towards bovine milk....
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.
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. PMID:21655841
Wang, Yong; Wang, Yao-Rong; Ying, Xi-Jun; Zhu, Xiao-Chun
According to "The Scheme of Schistosomiasis Surveillance in Zhejiang Province", the status of Oncomelania snails, and the schistosome infection of permanent residents, floating population, and livestock were surveyed in a provincial surveillance site of Shengzhou City, from 2008 to 2011. In 4 years, the area with residual snails was 3,060 m2, and no infected snails were found among 595 living snails. The positive rate of sero-tests for schistosomiasis of the permanent residents was 0.77%, and that of the floating population was 1.09%. No schistosomiasis cases were found. In conclusion, the area with residual snails is small and its distribution is scattered, and we still should strengthen the surveillance of snail status and imported schistosomiasis cases. PMID:23687831
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.
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. PMID:27137455
Full Text Available Abstract Background Praziquantel has been used as first-line drug for chemotherapy of schistosomiasis since 1984. Besides praziquantel, artemether and artesunate have also been used for the control of this infectious disease since late 1990s. In this article, we conducted a systematic review and meta-analysis to evaluate the antischistosomal efficacy of different medication strategies including monotherapy or combination therapies of these drugs. Results A number of 52 trials from 38 articles published in peer-reviewed journals before July 2011 were selected for analysis after searching the following literature databases: the Cochrane Library, PubMed/Medline, ISI Web of Science, Chinese Biomedicine Literature Database, and China National Knowledge Infrastructure. Our meta-analyses showed that a dosage of 30-60 mg/kg praziquantel compared with placebo produced a protection rate of about 76% (95% CI: 67%-83% for treating human schistosomiasis, which varied from 70% to 76% with no significant differences among the subspecies S. haematobium, S. japonicum or S. mansoni. Protection rates were higher when praziquantel doses were elevated, as concluded from the nRCTs results: the protection rate of praziquantel at 40 mg/kg was 52% (95% CI: 49%-55%, and it increased to 91% (95% CI: 88%-92% when the dosages were elevated to 60/80/100 mg/kg divided two or more doses. Multiple doses of artemether or artesunate over 1- or 2-week intervals resulted in protection rates of 65% to 97% for preventing schistosomiasis, and increased doses and shorter medication intervals improved their efficacies. Praziquantel and artemisinin derivatives (artemether or artesunate in combination resulted in a higher protection rate of 84% (95% CI: 64%-91% than praziquantel monotherapy for treatment. praziquantel and artesunate in combination had a great protection rate of 96% (95% CI: 78%-99% for preventing schistosomes infection. Conclusions According to the results, praziquantel
Full Text Available BACKGROUND: Studies in murine models and human populations have indicated that the collagen-rich granulomatous response against parasite eggs trapped in the liver is associated with the development of severe hepatosplenic schistosomiasis, characterized by periportal fibrosis and portal hypertension. The role of the humoral response in parasite susceptibility has been well established, but its participation in disease severity remains poorly understood. In this work, we evaluated the relationship between parasite-reactive IgE and IgG levels and schistosomiasis morbidity in infected patients with similar parasite burdens. METHODOLOGY/PRINCIPAL FINDINGS: Ninety-seven Schistosoma mansoni-infected individuals were subjected to clinical examination and abdominal ultrasound analysis. IgG reactivity and IgE concentration against Schistosoma mansoni soluble egg antigens (SEA and adult worm antigen preparation (SWAP were evaluated by ELISA assay. Multivariable linear regression models were used to evaluate the relationship between parasite-reactive antibodies and the co-variables investigated. The study population showed low parasite burden (median 30 eggs/g feces, constant re-infection, and signs of fibrosis was detected in more than 30% of individuals. Most infected individuals showed IgG reactivity, and the median concentrations of IgE anti-SEA and anti-SWAP antibodies were 1,870 and 1,375 ng/mL, respectively. There was no association between parasite burden and antibody response or any parameter of disease severity. However, IgG anti-SWAP level was positively associated with morbidity parameters, such as spleen size and thickness of portal vein at the entrance and secondary branch. In contrast, the data also revealed independent inverse correlations between concentration of parasite-reactive IgE and gallbladder wall thickness, a marker of fibrosis in schistosomiasis. CONCLUSIONS/SIGNIFICANCE: The data indicate that IgG anti-SWAP is positively
Duval, David; Galinier, Richard; Mouahid, Gabriel; Toulza, Eve; Rognon, Anne; Arancibia, Nathalie; Allienne, Jean-François; Mitta, Guillaume; Théron, André; Gourbal, Benjamin
Schistosomiasis is the second most widespread tropical parasitic disease after malaria. To achieve the objective of schistosomiasis eradication in a decade, various research strategies and treatment programs were recommended and supported by WHO. One of these applicable approaches is based on the control of snail vectors in endemic area. Previous field studies have shown that competitor or predator introduction could be effective but no systemic investigation has ever been conducted to identi...
Carvalho-Queiroz, Claudia; Nyakundi, Ruth; Ogongo, Paul; Rikoi, Hitler; Egilmez, Nejat K.; Farah, Idle O; Thomas M Kariuki; LoVerde, Philip T.
Schistosomiasis remains a major cause of morbidity in the world. The challenge today is not so much in the clinical management of individual patients, but rather in population-based control of transmission in endemic areas. Despite recent large-scale efforts, such as integrated control programs aimed at limiting schistosomiasis by improving education and sanitation, molluscicide treatment programs and chemotherapy with praziquantel, there has only been limited success. There is an urgent need...
Summary This paper reviews recent studies on the spatial epidemiology of human schistosomiasis in Africa. The integrated use of geographical information systems, remote sensing and geostatistics has provided new insights into the ecology and epidemiology of schistosomiasis at a variety of spatial scales. Because large-scale patterns of transmission are influenced by climatic conditions, an increasing number of studies have used remotely sensed environmental data to predict spatial distributio...
Grimes, J. E. T.; Croll, D.; Harrison, W. E.; Utzinger, J; Freeman, M. C.; Templeton, M. 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 ...
Schistosomiasis is caused by infection with the parasite Schistosoma, which is a flat-worm or fluke. The dominant species are Schistosoma mansoni, Schistosoma japonicum, and Schistosoma haematobium. Schistosomiasis is the third most common parasitic disease in the world after malaria and amoebiasis. It is endemic in more than 70 countries affecting about 200 million people worldwide, of whom 80% are in sub-Saharan Africa. There are pockets of infection in north-eastern Brazil, near the Yangtz...
Poda, J N; Wango, S P; Sorgho, H; Dianou, D
In order to help the hydro-agricultural projects in the management of water resources together with a schistosomiasis control programme, it is important to evaluate the extent of the problem. This is the reason why parasitological and clinical surveys were conducted in schools associated with malacological surveys in transmission sites of several water projects including the one from Sourou. The data-collecting for the research on molluscs was carried out in surface water and as for parasitologic investigations on school-aged children, urine filtration and Kato-Katz were used to evaluate the parasitic load. The levels of prevalence were respectively in Guiédougou, Niassan, Di and Toma-île, in 2000, 60.5%, 40%, 48.8% and 51.9% for the urinary schistosomiasis, 5.3%, 0%, 6.9% and 50.6% for the intestinal schistosomiasis and in 2002, 56%, 51.9%, 51.6% and 43.4% for the urinary schistosomiasis, 10.1%, 8.2%, 22.7% and 90.8% for the intestinal schistosomiasis. The molluscs species collected and identified were: Biomphalaria pfeifferi for the intestinal schistosomiasis and Bulinus truncatus rohlfsi and B. senegalensis for the urinary schistosomiasis. B. senegalensis and B. truncatus were found naturally infested by S. haematobium. Water projects constitute amplifying factors of the proliferation of the species and parasitic exchange. All the actors (developers, populations, scientists) are questioning the means at their disposal to reduce the development of schistosomiasis which decrease the expected benefit of hydro-agricultural installations. PMID:15104151
Kedma de Magalhães Lima; Melissa Negro-Dellacqua; Victor Emmanuell Fernandes Apolônio dos Santos; Célia Maria Machado Barbosa de Castro
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...
Hu, Yi; Ward, Michael P; Xia, Congcong; Li, Rui; Sun, Liqian; Lynn, Henry; Gao, Fenghua; Wang, Qizhi; Zhang, Shiqing; Xiong, Chenglong; Zhang, Zhijie; Jiang, Qingwu
Schistosomiasis remains a major public health problem and causes substantial economic impact in east China, particularly along the Yangtze River Basin. Disease forecasting and surveillance can assist in the development and implementation of more effective intervention measures to control disease. In this study, we applied a Bayesian hierarchical spatio-temporal model to describe trends in schistosomiasis risk in Anhui Province, China, using annual parasitological and environmental data for the period 1997-2010. A computationally efficient approach-Integrated Nested Laplace Approximation-was used for model inference. A zero-inflated, negative binomial model best described the spatio-temporal dynamics of schistosomiasis risk. It predicted that the disease risk would generally be low and stable except for some specific, local areas during the period 2011-2014. High-risk counties were identified in the forecasting maps: three in which the risk remained high, and two in which risk would become high. The results indicated that schistosomiasis risk has been reduced to consistently low levels throughout much of this region of China; however, some counties were identified in which progress in schistosomiasis control was less than satisfactory. Whilst maintaining overall control, specific interventions in the future should focus on these refractive counties as part of a strategy to eliminate schistosomiasis from this region. PMID:27053447
Schistosomiasis is caused by infection with the parasite Schistosoma, which is a flat-worm or fluke. The dominant species are Schistosoma mansoni, Schistosoma japonicum, and Schistosoma haematobium. Schistosomiasis is the third most common parasitic disease in the world after malaria and amoebiasis. It is endemic in more than 70 countries affecting about 200 million people worldwide, of whom 80% are in sub-Saharan Africa. There are pockets of infection in north-eastern Brazil, near the Yangtze River in China, and some pockets in south East Asia. In the East Mediterranean regions, the Schistosoma have been reported in Iraq and Egypt as well as in Sudan. The latter has the highest infection rate nowadays, particularly in the Al Jazeera area, due to the poor Schistosoma control program. In the Arabian peninsula, schistosomiasis has been reported in southwest part of Saudi Arabia, mainly in the Asir province and Jizan province, which lay in the southwest corner of Saudi Arabia and directly north of the border with Yemen. The efforts to control schistosomiasis have been very successful in Saudi Arabia due to the irrigation system control. However, the infection is prone in Yemen, where the schistosomiasis control is much less strict. Thus as a result, the problem still exists due to transmigration of the populations from both countries. As a cause of pulmonary arterial hypertension (PAH), schistosomiasis is still under diagnosed and undertreated. This article with give a highlight about the pathophysiology of the disease and both diagnostic and therapeutic strategies. PMID:25076995
Full Text Available Schistosomiasis is caused by infection with the parasite Schistosoma, which is a flat-worm or fluke. The dominant species are Schistosoma mansoni, Schistosoma japonicum, and Schistosoma haematobium. Schistosomiasis is the third most common parasitic disease in the world after malaria and amoebiasis. It is endemic in more than 70 countries affecting about 200 million people worldwide, of whom 80% are in sub-Saharan Africa. There are pockets of infection in north-eastern Brazil, near the Yangtze River in China, and some pockets in south East Asia. In the East Mediterranean regions, the Schistosoma have been reported in Iraq and Egypt as well as in Sudan. The latter has the highest infection rate nowadays, particularly in the Al Jazeera area, due to the poor Schistosoma control program. In the Arabian peninsula, schistosomiasis has been reported in southwest part of Saudi Arabia, mainly in the Asir province and Jizan province, which lay in the southwest corner of Saudi Arabia and directly north of the border with Yemen. The efforts to control schistosomiasis have been very successful in Saudi Arabia due to the irrigation system control. However, the infection is prone in Yemen, where the schistosomiasis control is much less strict. Thus as a result, the problem still exists due to transmigration of the populations from both countries. As a cause of pulmonary arterial hypertension (PAH, schistosomiasis is still under diagnosed and undertreated. This article with give a highlight about the pathophysiology of the disease and both diagnostic and therapeutic strategies.
Full Text Available The transmission of schistosomiasis is still ongoing in Dodolo and Mekarsari Villages ofNapu highland, Poso District. The people who infected with Schistosoma japonicum, intermediate host. Oncomelania hnpensis lindoensis snails that infected by cercaria. infective stage of S. japonicum and reservoir host, rats, which infected by S. japonicum were still (bund. The purpose of this study was to identify the transmission of schistosomiasis at Dodolo and Mekarsari Villages, Napu highland. The epidemiological investigation was analyzed using observational study with cross sectional design. Data collections were conducted, including stool, snail and rat suryeys. Stool samples were examined by the Kato-Katz method and rats were dissected to identify the prevalence rate of schistosomiasis in human and rats. Snails were examined using crushing method to identify the infection rate of the snails. Prevalence rate of schistosomiasis in human, rats (Rattus exulans and infection rate O. hnpensis lindoensis snails in Dodolo were 6,9%, 8,3%, 2,8% and in Mekarsari were 6,1%, 10% 2,6% respectively. Prevalence of schistosomiasis in Dodolo and Mekarsari villages is still high, so we need continuous surveillance. Keywords: Schistosomiasis, Schistosoma japonicum, O. hupensis lindoensis, Dodolo, Mekarsari
Zandersen, Marianne; Hyytiäinen, Kari; Saraiva, Sofia;
This document serves as a background material to the BONUS Pilot Scenario Workshop, which aims to develop harmonised regional storylines of socio-ecological futures in the Baltic Sea region in a collaborative effort together with other BONUS projects and stakeholders.......This document serves as a background material to the BONUS Pilot Scenario Workshop, which aims to develop harmonised regional storylines of socio-ecological futures in the Baltic Sea region in a collaborative effort together with other BONUS projects and stakeholders....
José C Sousa-Figueiredo
Full Text Available BACKGROUND: 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. METHODOLOGY/PRINCIPAL FINDINGS: 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. CONCLUSION/SIGNIFICANCE: 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
A 47-year-old Chinese male, born in Hong Kong, but living in the Netherlands since the age of 16, was admitted to hospital complaining of right upper abdominal pain. Real-time ultrasonography of the liver showed a lobulated structure with hyperechogenic septa surrounding normal liver tissue. There was no evidence of periportal fibrosis. The diameter of the main portal vein and the size of the spleen were normal. Computed tomography demonstrated capsular and septal calcifications, causing a lobulated pattern similar to the ultrasonographic image. There was no enhancement of the septa or other structures after intravenous administration of contrast medium. The liver and spleen were not enlarged. The computed tomography diagnosis of Schistosomiasis japonica was definitely confirmed by liver biopsy. 8 refs.; 3 figs
Pedalino, M; Vercesi, E; Manini, C; Piras, D; Di Primio, O G; Vella, R; Marino, G
Authors present a case of bilharziosis incidentally diagnosed in a patient undergoing TURB for suspected bladder cancer. The patient, who in 2005 had gone to Malaysia, had been suffering from recurrent hemorrhagic cystitis since 2007, which were treated with antibiotic therapy. In November 2009 he presented to our observation for persistent hematuria, underwent ultrasound examination, fibroscopy and TURB diagnostics for suspicious lesions. The histopathology diagnosis found granulomatous lesions with typical parasites eggs due to schistosomiasis eggs. As a consequence of that, the patient underwent medical therapy. The pathologist's role becomes nullifying not only for the diagnosis of parasitic infections but also for the exclusion or evidence of urothelial squamous neoplasia. The low incidence of this rare parasitic disease in European tourists and the presence of immigrants in our country require to spread the knowledge of these parasites and the most simple tests for early detection. PMID:21308673
Clarice Neuenschwander Lins de Morais
Full Text Available The production and regulation of interleukin (IL IL-13, IL-4 and interferon-gamma (IFN-³ was evaluated in 43 schistosomiasis patients with different clinical forms. Whole-blood cultures cytokine production in response to soluble egg antigen (SEA, soluble worm adult preparation (SWAP, mitogens, neutralizing antibodies or recombinant IL-13 were measured by ELISA. After SWAP stimulation, chronic patients, particularly hepatointestinals, produced higher levels of IL-4 in comparison with acute patients, suggesting the presence of a type 2 cytokine profile in these patients. Following SEA and SWAP stimulation, hepatosplenic (HS patients showed increased levels of IFN-³ when compared with acute patients, indicating that HS disease in humans is associated with a type 1 cytokine response. The mechanisms of immune regulation are apparently different between the clinical stages of the disease, some of which are antigen-specific.
Full Text Available Our views are based, on a recent study of a district of Uniao dos Palmares (Alagoas. Although being a very compact community (32 city blocks holding two thousand families, transmission is very uneven, the geometric mean egg counts in the various blocks ranging between extremes of 96 and 1920. (Results do not correlate with the availability of domestic water supply. We thus are led to conclude that: (a transmission is primarily peridomestic, resulting from pollution of open ditches and other collections of water; (b control of transmission can be done on a selective basis, requiring quite medest investments. Given the inefficacy of population-based chemotherapy, when used alone, the author insists that this alternative cannot any longer be overlooked. He also regrets the emphasis placed upon vaccine development; allegations that this would, at any rate, prevent severe morbidity can be dismissed, since-whatever the cause-morbidity due to schistosomiasis has been rapidly declining in Northeast Brazil.
Wellenberg, Gerardus Johannus
Mastitis is an often occurring disease in dairy cattle with an enormous economic impact for milk producers worldwide. Despite intensive research, which is historically based on the detection of bacterial udder pathogens, still around 20-35% of clinical cases of bovine mastitis have an unknown aetiol
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.
Kallestrup, Per; Zinyama, Rutendo; Gomo, Exnevia;
To determine whether treatment of schistosomiasis has an effect on the course of human immunodeficiency virus type 1 (HIV-1) infection, individuals with schistosomiasis and with or without HIV-1 infection were randomized to receive praziquantel treatment at inclusion or after a delay of 3 months;......; 287 participants were included in the study, and 227 (79%) were followed up. Among the 130 participants who were coinfected, those who received early treatment (n=64) had a significantly lower increase in plasma HIV-1 RNA load than did those who received delayed treatment (n=66) (P...
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
Full Text Available 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
Full Text Available Abstract Background Intestinal schistosomiasis is often widespread among the populations living around Lake Victoria and on its islands. The Sesse Island group (containing some 84 islands, however, is typically assumed to be a low prevalence zone, with limited transmission, but has never been surveyed in detail. Here, we present a rapid mapping assessment, bringing together snail and parasite information, at 23 sites for the presence of intermediate host snails and at 61 sites for the prevalence of intestinal schistosomiasis in school-aged children (N = 905. Two different diagnostic tools were used and compared at 45 of these sites: Kato-Katz thick faecal smears and circulating cathodic antigen (CCA urine dipsticks. Results Biomphalaria snails were found at 11 sites but in low numbers; none was found shedding schistosome cercariae. At 22 out of the 45 sites, local prevalence by urine and/or stool diagnostics was in excess of 50%, although mean prevalence of intestinal schistosomiasis overall was 34.6% (95% confidence intervals (CI = 31.0-38.3% by Kato-Katz and 46.5% (95% CI = 42.7-50.4% by CCA if 'trace' reactions were considered infection-positive (if considered infection-negative, mean prevalence was 28.1% (95% CI = 24.7-31.7%. Diagnostic congruence between CCA and Kato-Katz was poor and significant discordance in estimated prevalence by location was found, with each often inferring different mass drug administration regimes. Conclusions Accurate estimation of schistosome prevalence is important for determining present and future treatment needs with praziquantel; the wide range of schistosome prevalence across the Sesse Island group requires a treatment regime largely tailored to each island. In high prevalence locations, further malacological sampling is required to confirm the extent of local transmission, especially on the northern islands within the group. The observation that different diagnostic tests can provide varying results in
Attwood Stephen W
Full Text Available Abstract Background The snail Neotricula aperta transmits Mekong schistosomiasis in southern Laos and Cambodia, with about 1.5 million people at risk of infection. Plans are under consideration for at least 12 hydroelectric power dams on the lower Mekong river and much controversy surrounds predictions of their environmental impacts. Unfortunately, there are almost no ecological data (such as long term population trend studies available for N. aperta which could be used in impact assessment. Predictions currently assume that the impacts will be the same as those observed in Africa (i.e., a worsening of the schistosomiasis problem; however, marked ecological differences between the snails involved suggest that region specific models are required. The present study was performed as an initial step in providing data, which could be useful in the planning of water resource development in the Mekong. Snail population density records were analyzed for populations close to, and far downstream of, the Nam Theun 2 (NT2 project in Laos in order to detect any changes that might be attributable to impoundment. Results The population immediately downstream of NT2 and that sampled 400 km downstream in Thailand both showed a long term trend of slow growth from 1992 to 2005; however, both populations showed a marked decline in density between 2005 and 2011. The decline in Thailand was to a value significantly lower than that predicted by a linear mixed model for the data, whilst the population density close to NT2 fell to undetectable levels in 2011 from densities of over 5000 m-2 in 2005. The NT2 dam began operation in 2010. Conclusions The impact of the NT2 dam on N. aperta population density could be more complex than first thought and may reflect the strict ecological requirements of this snail. There was no indication that responses of N. aperta populations to dam construction are similar to those observed with Bulinus and Schistosoma haematobium in
Utzinger, Jürg; Brattig, Norbert W; Kristensen, Thomas K
In May 2012, the World Health Assembly passed resolution WHA 65.21, calling upon member states to intensify schistosomiasis control and, wherever possible, to attempt transmission interruption and initiate interventions towards local elimination. It is now clear that CONTRAST--a multidisciplinary 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 and discuss its overarching goal, the interrelated objectives, establishment and running of a research node network across Africa, partnership configuration and modus operandi of the project. A collection of 25 articles is presented that are grouped into five main themes: molecular, biological, spatial, 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, the current piece provides an umbrella for the 25-article collection, including current gaps and remaining research needs. Finally, post-CONTRAST initiatives are discussed and a speculative viewpoint is given on how schistosomiasis control/elimination will have evolved over the next several years. PMID:23973364
Gunawan Gunawan; Hayani Anastasia; Phetisya Pamela F.S; Risti Risti
AbstrakSchistosomiasis merupakan penyakit parasitik jaringan yang terabaikan. Schistosomiasis adalah penyakit parasitik yang bersifat zoonosis, selain menginfeksi manusia juga menginfeksi hewan mamalia lainnya. Ada 13 mamalia yang diketahui dapat terinfeksi oleh schistosomiasis antara lain sapi(Bos sundaicus), kerbau (Bubalus bubalis), kuda (Equus cabalus), anjing (Canis familiaris), babi (Sus sp), musang (Vivera tangalunga), rusa (Carvus timorensis), dan berbagai jenis tikus (Rattus exulans,...
Valnickova, Zuzana; Thaysen-Andersen, Morten; Højrup, Peter;
BACKGROUND: TAFI is a plasma protein assumed to be an important link between coagulation and fibrinolysis. The three-dimensional crystal structures of authentic mature bovine TAFI (TAFIa) in complex with tick carboxypeptidase inhibitor, authentic full lenght bovine plasma thrombin-activatable fib......BACKGROUND: TAFI is a plasma protein assumed to be an important link between coagulation and fibrinolysis. The three-dimensional crystal structures of authentic mature bovine TAFI (TAFIa) in complex with tick carboxypeptidase inhibitor, authentic full lenght bovine plasma thrombin...
Wellenberg, Gerardus Johannus
Mastitis is an often occurring disease in dairy cattle with an enormous economic impact for milk producers worldwide. Despite intensive research, which is historically based on the detection of bacterial udder pathogens, still around 20-35% of clinical cases of bovine mastitis have an unknown aetiology. Due to the high number of unknown causes of clinical mastitis, studies were undertaken to gain more insight into the role of viruses in this important disease. For the first time, we found tha...
Łupicka, Martyna; Socha, Barbara; Szczepańska, Agata; Korzekwa, Anna
Background Adenomyosis is a proliferative uterine dysfunction with unknown aetiology. One possible mechanism of its development involves disturbances in stem cell differentiation in uterine tissue. Previously, we identified pluripotent/multipotent cells in the bovine uterus, therefore our present study focused on determining expression of pluripotency markers, NANOG, OCT4 and SOX2, in bovine adenomyotic tissues and cells. Findings Immunolocalisation revealed protein expression of NANOG, OCT4 ...
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
Carolina R Oliveira
Full Text Available BACKGROUND: Schistosomiasis is one of the most important neglected tropical diseases and an effective control is unlikely in the absence of improved sanitation and vaccination. A new approach of oral vaccination with alginate coated chitosan nanoparticles appears interesting because their great stability and the ease of target accessibility, besides of chitosan and alginate immunostimulatory properties. Here we propose a candidate vaccine based on the combination of chitosan-based nanoparticles containing the antigen SmRho and coated with sodium alginate. METHODS AND FINDINGS: Our results showed an efficient performance of protein loading of nanoparticles before and after coating with alginate. Characterization of the resulting nanoparticles reported a size around 430 nm and a negative zeta potential. In vitro release studies of protein showed great stability of coated nanoparticles in simulated gastric fluid (SGF and simulated intestinal fluid (SIF. Further in vivo studies was performed with different formulations of chitosan nanoparticles and it showed that oral immunization was not able to induce high levels of antibodies, otherwise intramuscular immunization induced high levels of both subtypes IgG1 and IgG2a SmRho specific antibodies. Mice immunized with nanoparticles associated to CpG showed significant modulation of granuloma reaction. Mice from all groups immunized orally with nanoparticles presented significant levels of protection against infection challenge with S. mansoni worms, suggesting an important role of chitosan in inducing a protective immune response. Finally, mice immunized with nanoparticles associated with the antigen SmRho plus CpG had 38% of the granuloma area reduced and also presented 48% of protection against of S. mansoni infection. CONCLUSIONS: Taken together, this results support this new strategy as an efficient delivery system and a potential vaccine against schistosomiasis.
Kabatereine Narcis B
Full Text Available Abstract Background It is widely advocated that integrated strategies for the control of neglected tropical diseases (NTDs are cost-effective in comparison to vertical disease-specific programmes. A prerequisite for implementation of control interventions is the availability of baseline data of prevalence, including the population at risk and disease overlap. Despite extensive literature on the distribution of schistosomiasis on the mainland in Uganda, there has been a knowledge gap for the prevalence of co-infections with malaria, particularly for island communities in Lake Victoria. In this study, nine lakeshore and island districts were surveyed for the prevalence of NTDs and malaria, as well as educational and health infrastructure. Results A total of 203 communities were surveyed, including over 5000 school-age children. Varying levels of existing health infrastructure were observed between districts, with only Jinja District regularly treating people for NTDs. Community medicine distributors (CMD were identified and trained in drug delivery to strengthen capacity. Prevalence levels of intestinal schistosomiasis and soil-transmitted helminthiasis were assessed via Kato-Katz thick smears of stool and malaria prevalence determined by microscopy of fingerprick blood samples. Prevalence levels were 40.8%, 26.04% and 46.4%, respectively, while the prevalence of co-infection by Schistosoma mansoni and Plasmodium spp. was 23.5%. Socio-economic status was strongly associated as a risk factor for positive infection status with one or more of these diseases. Conclusions These results emphasise the challenges of providing wide-scale coverage of health infrastructure and drug distribution in remote lakeshore communities. The data further indicate that co-infections with malaria and NTDs are common, implying that integrated interventions for NTDs and malaria are likely to maximize cost-effectiveness and sustainability of disease control efforts.
Charles H King
Full Text Available BACKGROUND: 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. METHODOLOGY/PRINCIPAL FINDINGS: 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. CONCLUSIONS/SIGNIFICANCE: 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
Maphumulo, Andile A; Gagai, Silindile; Lothe, Andrea;
Introduction: Schistosomiasis is a parasitic disease that affects developing countries; it has economic and public health significance. WHO recommends regular treatment for schistosomiasis in endemic areas and has that estimated that more than 5 million individuals require treatment in South Africa...
Nalugwa, A.; Olsen, Annette; Tukahebwa, M. E.;
Schistosomiasis, a disease caused by Schistosoma trematode parasites, affects hundreds of millions of people and accounts for more than 40% of the global health burden due to neglected tropical diseases. In Uganda, intestinal schistosomiasis is endemic in 73 out of 112 districts and about 55% of ...... for schistosomiasis takes preschool children into consideration and that health education on transmission of schistosomiasis is delivered to the endemic communities regularly.......% of the population of 36 million individuals are at risk. There is scanty information on the status and burden of schistosomiasis in preschool children less than six years of age in Uganda. This study aimed to assess the status of Schistosoma mansoni infections in children aged 1-5 years in Uganda. S. mansoni...... in the age group 12-24 months (84.2%; 95% CI: 75.6-90.1%), were lightly infected. Short interviews with caregivers revealed that preschool children, 1-5 years old, get exposed to S. mansoni infested waters through bathing, playing or swimming. It is important that the Uganda national control programme...
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. PMID:27430549
Dawaki, Salwa; Al-Mekhlafi, Hesham Mahyoub; Ithoi, Init; Ibrahim, Jamaiah; Abdulsalam, Awatif Mohammed; Ahmed, Abdulhamid; Sady, Hany; Atroosh, Wahib Mohammed; Al-Areeqi, Mona Abdullah; Elyana, Fatin Nur; Nasr, Nabil Ahmed; Surin, Johari
Schistosomiasis remains one of the most prevalent neglected tropical diseases especially in Nigeria which has the greatest number of infected people worldwide. A cross-sectional study was conducted among 551 participants from Kano State, North Central Nigeria. Fecal samples were examined for the presence of Schistosoma mansoni eggs using the formalin-ether sedimentation method while the urine samples were examined using the filtration technique for the presence of S. haematobium eggs. Demographic, socioeconomic and environmental information was collected using a pre-validated questionnaire. The overall prevalence of schistosomiasis was 17.8%, with 8.9% and 8.3% infected with S. mansoni and S. haematobium, respectively and 0.5% presenting co-infection with both species. The multiple logistic regression analysis revealed that age history of infection (OR = 2.87; 95% CI; 1.87- 4.56) were the significant risk factors associated with schistosomiasis in these communities. In conclusion, this study revealed that schistosomiasis is still prevalent among Hausa communities in Nigeria. Mass drug administration, health education and community mobilization are imperative strategies to significantly reduce the prevalence and morbidity of schistosomiasis in these communities. PMID:27410914
Coelho, Pmz; Caldeira, R L
In Brazil, Biomphalaria glabrata, B. tenagophila, and B. straminea are naturally infected by the trematode Schistosoma mansoni, the causative agent of schistosomiasis. Despite decades of governmental efforts through official control programs, schistosomiasis remains an important public health problem in the country: thousands of people are infected with the trematode each year and millions live in endemic areas. The World Health Organization recommends using a combination of molluscicide (niclosamide) and mass chemotherapy to control the transmission of schistosomiasis, with this treatment successfully reducing the morbidity of the disease. In the past, niclosamide has been used in official schistosomiasis control programs in Brazil. However, as B. glabrata recolonizes even after molluscicide application, the use of molluscicides has gradually decreased in the country until they were discontinued in 2002, mainly due to the rising global pressure to preserve the environment and the difficulties of obtaining licenses from the Brazilian Ministry of Environment to use toxic substances in aquatic ecosystems. Therefore, the discovery of new molluscicides, which could be more selective to Biomphalaria species and less harmful to the aquatic ecosystem, is necessary. In addition, political efforts to sensitize funders to provide grants for this field of research are required. In this context, this article aims to make a critical analysis of molluscicide application in schistosomiasis control programs in Brazil. PMID:27374126
The objectives of the present study were to determine the efficacy of schistosomiasis laboratory diagnostic techniques, used in hospitals, in identifying those infected with S. mansoni and the possible role of the false negatives on the transmission of the disease. It was carried out in Abu Usher hospital, Gezira state. It compared two laboratory techniques, a qualitative and a quantitative method. The qualitative method was the direct smear method, used routinely in hospitals and health units. The quantitative technique was the locally modified kato method, used in research, epidemiological studies and evaluation of schistosomiasis control programmes. 288 stool samples from the hospital out patients were examined by the direct smear and the kato methods. The direct smear method indicated that 277 (96.8%) of the total examined un-infected. Examination of the stools by the kato method revealed that 161 (55.9%) were infected with S. mansoni. The difference between the numbers found infected by the two methods was highly significant (P<0.001). The intensity of infection of those found infected were categorized arbitrary into four groups: lightly (1-100 eggs/g), moderately (101-500 eggs/g), heavily (501-1000 eggs/g), and very heavily (1001+eggs/g) infected respectively. The majority of those examined were with low and moderate intensity of infection with S.mansoni, 42.23% and 46.58% respectively. The direct smear method failed to identify those with light, moderate and heavy infection. Only 3 (27.3%) out of 11 of the very heavily infected persons were detected by this technique. The difference in detecting the heavily infected person by the two diagnostic methods was significant (P<0.025). Biomphalaria pfeifferi snails were infected individually with 1, 2 and 4 miracidia. B. pfeifferi snails infected with 1 miracidium did not produce any cercariae. All infected surviving snails died 11 days after they started to shed cercariae. The control snails survived for two
... Ask about Your Treatment Research Cartilage (Bovine and Shark) (PDQ®)–Patient Version Overview Go to Health Professional ... 8 ). Questions and Answers About Cartilage (Bovine and Shark) What is cartilage? Cartilage is a type of ...
Gutiérrez, Gerónimo; Alvarez, Irene; Merlini, Ramiro; Rondelli, Flavia; Trono, Karina
Background Bovine leukemia virus (BLV) is highly endemic in many countries, including Argentina. As prevention of the spread from infected animals is of primary importance in breaking the cycle of BLV transmission, it is important to know the pathophysiology of BLV infection in young animals, as they are the main source of animal movement. In this work, we determined the proviral load and antibody titers of infected newborn calves from birth to first parturition (36 months). Results All calve...
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
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.
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.
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.
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.
Xavier Suresh R
Full Text Available Abstract Background Many important agricultural traits such as weight gain, milk fat content and intramuscular fat (marbling in cattle are quantitative traits. Most of the information on these traits has not previously been integrated into a genomic context. Without such integration application of these data to agricultural enterprises will remain slow and inefficient. Our goal was to populate a genomic database with data mined from the bovine quantitative trait literature and to make these data available in a genomic context to researchers via a user friendly query interface. Description The QTL (Quantitative Trait Locus data and related information for bovine QTL are gathered from published work and from existing databases. An integrated database schema was designed and the database (MySQL populated with the gathered data. The bovine QTL Viewer was developed for the integration of QTL data available for cattle. The tool consists of an integrated database of bovine QTL and the QTL viewer to display QTL and their chromosomal position. Conclusion We present a web accessible, integrated database of bovine (dairy and beef cattle QTL for use by animal geneticists. The viewer and database are of general applicability to any livestock species for which there are public QTL data. The viewer can be accessed at http://bovineqtl.tamu.edu.
Pessa-Morikawa Tiina; Ekman Anna; Niku Mikael; Iivanainen Antti
Abstract Background Identification of cell types in bovine tissue sections is complicated by the limited availability of anti-bovine antibodies, and by antigen retrieval treatments required for formalin-fixed tissue samples. We have evaluated an antibody and lectin panel for identifying major cell types in paraffin-embedded bovine tissue sections, and report optimized pretreatments for these markers. Results We selected 31 useful antibodies and lectins which can be used to identify cell types...
Polguj, Michał; Wysiadecki, Grzegorz; Podgórski, Michał; Szymański, Jacek; Olbrych, Katarzyna; Olewnik, Łukasz; Topol, Mirosław
Background Proper blood supply is necessary for the physiological function of every internal organ. The article offers the first classification of the bovine intra-testicular arteries. A corrosive study focused on the intra-testicular arterial vasculature was performed on 40 bovine testes. The vessels were analyzed accurately using MultiScanBase v.18.02 software. Methods A corrosive study focused on the intra-testicular arteries was performed on 40 bovine testes. The vessels were analyzed acc...
Mostafa, Nahed E; Awad, Adel; Shalaby, Mohsen
One hundred thirty school children from a schistosomiasis endemic area in Sharkia Governorate, were selected on parasitological findings. Seventy persons were negative on the first screen and turned positive after 3 months of the screening (recently infected). Stool examination, ELISA (IgG & IgM), low avid IgG, and circulating antigens were performed for all patients and controls. ELISA detected IgM in all cases. IgG and circulating antigens in 90% of schistosomiasis patients. Low avidity IgG were detected in 85.71% of recent cases. The specificity of ELISA appeared to be >99%. The IgM/IgG ratio was >1 in patients with recent infection. The percentage of fall of O.D. readings of IgG after addition of 6 molar urea was high among cases with recent infection. Low avid lgG appears to be good and valuable in diagnosis of recent schistosomiasis in man. PMID:12512829
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
Ludmila N. Rapado
Full Text Available The search of alternative compounds to control tropical diseases such as schistosomiasis has pointed to secondary metabolites derived from natural sources. Piper species are candidates in strategies to control the transmission of schistosomiasis due to their production of molluscicidal compounds. A new benzoic acid derivative and three flavokawains from Piper diospyrifolium, P. cumanense and P. gaudichaudianum displayed significant activities against Biomphalaria glabrata snails. Additionally, “in silico” studies were performed using docking assays and Molecular Interaction Fields to evaluate the physical-chemical differences among the compounds in order to characterize the observed activities of the test compounds against Biomphalaria glabrata snails.
Gomes Yara M
Full Text Available In the present communication we analyzed the levels of IgG1, IgG2, IgG3, IgG4 and IgE isotypes to soluble egg antigen of Schistosoma mansoni by ELISA in individuals from an endemic area for schistosomiasis in Northeast Brazil. The analysis was performed before and after treatment to evaluate the age-dependent pattern, and to identify differences in the reactivities to antigens. Our results suggest that schistosomiasis treatment would not interfere with this sort of immune response.
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...... 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...
Demetrius da Silva Martins
Full Text Available INTRODUCTION: Schistosomiasis, a parasitic disease, is an important public health issue in Brazil, particularly Northern Brazil. Since the first recorded occurrence of Biomphalaria glabrata in the States of Santa Catarina and Rio Grande do Sul, it has spread to South Brazil. METHODS: Using the Information System for Notifiable Diseases (SINAN, we assessed the disease spread in Southern Brazil. RESULTS: In Rio Grande do Sul, nine localities had confirmed cases (n = 95, 2001-2013. CONCLUSIONS: We confirmed disease expansion to Southern Brazil. We demonstrated the effectiveness of SINAN to monitor notifiable diseases. Our results are useful to develop preventive actions for schistosomiasis control.
Ngarakana-Gwasira, E. T.; Bhunu, C. P.; Masocha, M.; Mashonjowa, E.
Temperature and presence of water bodies are known to influence the transmission dynamics of schistosomiasis. In this work, effects of water bodies (taken in context of rainfall patterns) and temperature from 1950 to 2000 are considered in the model. With the aid of Geographic Information System (GIS), the reproduction number is mapped on the Zimbabwean country. Results of the mapping show high reproduction numbers along the Lowveld and the Zambezi valley catchment area. High reproduction numbers suggest high levels of schistosomiasis. This result suggests more control efforts should be targeted in these areas with high reproduction numbers.
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
Rapado, Ludmila Nakamura; Pinheiro, Alessandro de Sá; Lopes, Priscila Orechio de Moraes Victor; Fokoue, Harold Hilarion; Scotti, Marcus Tullius; Marques, Joaquim Vogt; Ohlweiler, Fernanda Pires; Borrely, Sueli Ivone; Pereira, Carlos Alberto de Bragança; Kato, Massuo Jorge; Nakano, Eliana; Yamaguchi, Lydia Fumiko
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 environment. PMID
Ba'amer Abobakar Ahmed
Full Text Available "nBackground: The study was conducted to estimate and compare the validity and performance of two screening methods for urinary schistosomiasis: the interview - reporting blood in urine- and detecting microhematuria by reagent strip."nMethods: In year 2003, 515 schoolchildren from five schools in Abyan and Taiz governorates in Yemen, were in-terviewed by healtworker for hematuria, and then urine samples were collected and tested for microhematuria by urine strip and for the presence and count of Schistosoma hematobium by filtration method. Validity and performance indicators were estimated and compared for the two methods using the filtration method as the reference- standard- test."nResults: The mean age of the schoolchildren was 10.7±2.5 years. Boys represented 65% of the sample. The prevalence of the infection as determined by filtration, interview and reagent strip methods was 21.4%, 22.15, and 30.9%, respectively. Sensitivity, specificity, PPV, NPV of the urine strip was higher than the same indicators for the interview method. Combining the results of both screening methods increased all validity and performance indicators. A statically significant (P< 0.001 association was found between urine strip positivity level and infection intensity."nConclusion: The urine strip had higher validity and performance indicators than the interview method. For its low -cost, simple and rapid application, we recommend using it for screening infected schoolchildren in areas endemic with S. hematobium in combination with the interview method to enhance its performance.
Exosomes are 40-100 nm membrane vesicles of endocytic origin and are found in blood, urine, amniotic fluid, bronchoalveolar lavage (BAL) fluid, as well as human and bovine milk. Exosomes are extracellular organelles important in intracellular communication/signaling, immune function, and biomarkers ...
Bovine spongiform encephalopathy (BSE), also referred to as “mad cow disease” is a chronic, non-febrile, neuro-degenerative disease affecting the central nervous system. The transmissible spongiform encephalopathies (TSEs) of domestic animals, of which BSE is a member includes scrapie of sheep...
Bovine viral diarrhea virus (BVDV) is an umbrella term for two species of viruses, BVDV1 and BVDV2, within the Pestivirus genus of the Flavivirus family. BVDV viruses are further subclassified as cytopathic and noncytopathic based on their activity in cultured epithelial cells. Noncytopathic BVDV p...
Bovine coronaviruses (BoCV) are enveloped, single-stranded, positive-sense RNA viruses of the Coronaviridae family. Infection is associated with enteritis and pneumonia in calves and Winter Dysentery in adult cattle. Strains, isolated more than 50 years ago, are used in vaccines and as laboratory ...