Showing papers on "Schistosoma haematobium published in 2004"

Spatial patterns of urinary schistosomiasis infection in a highly endemic area of coastal Kenya.

Abstract: Urinary schistosomiasis remains a major contributor to the disease burden along the southern coast of Kenya. Selective identification of transmission hot spots offers the potential for more effective, highly-focal snail control and human chemotherapy to reduce Schistosoma haematobium transmission. In the present study, a geographic information system was used to integrate demographic, parasitologic, and household location data for an endemic village and neighboring households with the biotic, abiotic, and location data for snail collection/water contact sites. A global spatial statistic was used to detect area-wide trends of clustering for human infection at the household level. Local spatial statistics were then applied to detect specific household clusters of infection, and, as a focal spatial statistic, to evaluate clustering of infection around a putative transmission site. High infection intensities were clustered significantly around a water contact site with high numbers of snails shedding S. haematobium cercariae. When age was considered, clustering was found to be significant at different distances for different age groups.

Infant schistosomiasis in Ghana: a survey in an irrigation community.

Abstract: We used a rapid, visually read, field applicable monoclonal antibody (MoAb)-dipstick assay for specific diagnosis of urinary schistosomiasis together with microscopy to determine the prevalence of infant schistosomiasis in a community in the Awutu-Efutu Senya District in the Central Region of Ghana. The study group consisted of 97 infants (51 males and 46 females) aged 2 months to 5 years. A total of 75 of 97 (77.3%) subjects submitted stool samples; none had Schistosoma mansoni. Three individuals (3.1%) had hookworms but there were no other intestinal helminths. The urinary schistosomiasis prevalence by MoAb-dipstick (30%) was higher (P < 0.05) than that estimated by microscopy (11.2%). However, three of nine (33.3%) microscopically confirmed cases tested MoAb-dipstick positive after pre-treatment of the urine specimen with heat. The youngest infant to be found infected with S. haematobium microscopically was 4 months old. Fifteen of 71 S. haematobium egg negative individuals tested dipstick positive, giving a dipstick specificity of 78.9% as compared with microscopy as gold standard test. The relative sensitivity of the dipstick was 100%.

Large-scale, polymerase chain reaction–based surveillance of schistosoma haematobium dna in snails from transmission sites in coastal kenya: a new tool for studying the dynamics of snail infection

Abstract: Levels of prepatent Schistosoma haematobium infection were monitored in intermediate host snails (Bulinus nasutus) collected from transmission sites in coastal Kenya, using a polymerase chain reaction (PCR) assay amplifying the Dra I repeated sequence of S. haematobium. The timing and number of prepatent and patent infections were determined for each site and, where the time of first appearance was clear, the minimal prepatent period was estimated to be five weeks. High, persistent, prepatency rates (range = 28-54%), indicated a significant degree of repeated area contamination with parasite ova. In contrast, rates of cercarial shedding proved locally variable, and were either low (range = 0.14-3.4%) or altogether absent, indicating that only a small proportion of infected snails reach the stage of cercarial shedding. Given the apparently strong focal effects of environmental conditions, implications of these new data are discussed regarding the estimation of local force of transmission and the design of control activities.

Distribution patterns and cercarial shedding of bulinus nasutus and other snails in the msambweni area, coast province, kenya

Abstract: In the Msambweni area of the Kwale District in Kenya, an area endemic for Schistosoma haematobium, potential intermediate-host snails were systematically surveyed in water bodies associated with human contact that were previously surveyed in the 1980s. Bulinus (africanus) nasutus, which accounted for 67% of the snails collected, was the only snail shedding S. haematobium cercariae. Lanistes purpureus was the second most common snail (25%); lower numbers of Bulinus forskalii and Melanoides tuberculata were also recovered. Infection with non-S. haematobium trematodes was found among all snail species. Rainfall was significantly associated with the temporal distribution of all snail species: high numbers of Bulinus nasutus developed after extensive rainfall, followed, in turn, by increased S. haematobium shedding. Spatial distribution of snails was significantly clustered over a range of up to 1 km, with peak clustering observed at a distance of 400 meters. Water lily (Nymphaea spp.) and several aquatic grass species appeared necessary for local colonization by B. nasutus or L. purpureus.

Schistosomiasis co-infection in humans influences inflammatory markers in uncomplicated Plasmodium falciparum malaria

Abstract: Malaria and schistosomiasis are the two major parasite diseases present in developing countries. The epidemiological co-infection with schistosomiasis could influence the development of the physiological reaction associated with Plasmodium falciparum infection in human. Most studies have demonstrated the association of circulating levels of interferon-gamma (IFN-gamma), tumour necrosis factor-a (TNF-alpha), interleukin-10 (IL-10), transforming growth factor (TGF-beta) and soluble Tumour Necrosis Factor Receptors (sTNF-RI and sTNF-RII) with the morbidity of malaria. In the present study, we showed that Schistosoma haematobium co-infection influences, in an age-dependent manner, the unbalance between pro- and anti-inflammatory circulating cytokines that play a key role during malaria infection. Indeed, children co-infected by S. haematobium have higher levels of IFN-gamma and sTNF-RII than children infected only by P. falciparum. In contrast, co-infected adults presented a significant increase of IFN-gamma, IL-10, TGF-beta, sTNF-RI and sTNF-RII rates and IL-10/TNF-alpha ratio. Taken together, this study indicates that schistosomiasis co-infection can unbalance the regulation of inflammatory factors in uncomplicated P. falciparum malaria. The possible consequences of the schistosomiasis co-infection for age-dependent malaria morbidity are discussed.

Efficacy of praziquantel against Schistosoma haematobium infection in children

Abstract: A study was performed to determine the efficacy of praziquantel (PZQ) against Schistosoma haematobium. Children (n = 592) infected with S. haematobium received either a single treatment with PZQ (40 mg/kg) or two or three treatments with PZQ at three-week intervals after the initial treatment and efficacy was monitored for nine weeks. Cure rates at three-weeks post-treatment were low ( 83% and egg reduction rate > 98%) when assessed from six weeks post-treatment onward. There were no significant differences in cure rates or intensity of infection between the three cohorts at any point in the study, despite the different treatment regimens. Since children were in contact with transmission sites during the study period, the results suggest good efficacy of PZQ against all stages of S. haematobium, including the immature worms.

Human IgE response to the Schistosoma haematobium 22·6 kDa antigen

Abstract: Fitzsimmons, C. M., Stewart, T. J., Hoffmann, K. F., Grogan, J. L., Yazdanbakhsh, M., Dunne, D. W. (2004). Human IgE response to the Schistosoma haematobium 22.6 kDa antigen. Parasite Immunology, 26 (8-9), 371-376

Increased Ratio of Tumor Necrosis Factor-α to Interleukin-10 Production Is Associated with Schistosoma haematobium-Induced Urinary-Tract Morbidity

Abstract: Bladder and kidney disease, which affect approximately 25%-30% of subjects infected with Schistosoma haematobium, are mediated by T cell-dependent granulomatous responses to schistosome eggs. To determine why only some infected subjects develop disease, we examined the hypothesis that infected Kenyan subjects with ultrasound-detected urinary-tract morbidity (n=49) had dysregulated cytokine production leading to enhanced granulomatous responses, compared with subjects of similar age and intensity of infection without morbidity (n=100). Peripheral blood mononuclear cells from subjects with morbidity produced 8-fold greater levels of egg antigen-driven tumor necrosis factor (TNF)-alpha and had a 99-fold greater mean TNF-alpha:interleukin (IL)-10 ratio, compared with subjects without disease. No differences in cytokine response to non-egg-derived schistosome antigens were observed between groups. Subjects with morbidity had increased TNF-alpha production in response to endotoxin, suggesting an innate hyperresponsiveness. These results indicate that increased TNF-alpha production, relative to that of IL-10, is associated with developing bladder-wall morbidity with S. haematobium infection.

Low heritable component of risk for infection intensity and infection-associated disease in urinary schistosomiasis among wadigo village populations in coast province, Kenya

Abstract: To estimate their heritable component of risk for Schistosoma haematobium infection intensity and disease, we performed a community-based family study among an endemic population in coastal Kenya. Demography and family linkages were defined by house-to-house interviews, and infection prevalence and disease severity were assessed by standard parasitologic testing and by ultrasound. The total population was 4,408 among 912 households, with 241 identified pedigree-household groups. Although age- and sex-adjusted risk for greater infection intensity was clustered within households (odds ratio = 2.7), analysis of extended pedigree-household groups indicated a relatively low heritability score for this trait (h2 = 0.199), particularly after adjustment for common household exposure effects (adjusted h2 = 0.086). Statistical evidence was slightly stronger (h2 = 0.353) for familial clustering of bladder morbidity, with an adjusted h2 = 0.142 after accounting for household exposure factors. We conclude that among long-established populations of coastal Kenya, heritable variation in host susceptibility is low, and likely plays a minimal role in determining individual risk for infection or disease.

Efficacy of artesunate in the treatment of urinary schistosomiasis, in an endemic community in Nigeria.

Abstract: The efficacy and tolerability of oral artesunate for the treatment of urinary schistosomiasis was assessed among schoolchildren aged 5-18 years in Adim community, Nigeria. Overall, 500 children, randomly selected from those attending the Presbyterian primary school, were each invited to provide two consecutive urine samples. Using standard parasitological procedures, Schistosoma haematobium ova were found in the samples from 145 (29.0%) of the subjects. Most (87) of the infected subjects were then treated orally with artesunate, using two doses, each of 6 mg/kg, given 2 weeks apart. When the treated children were re-examined 4 weeks after the second dose of artesunate, 61 (70.1%) appeared egg-negative and were therefore considered cured. Post-treatment, the geometric mean egg count (GMEC) for the treated subjects who were not cured was significantly lower than the pre-treatment GMEC for all the treated subjects, with log10[(eggs/10 ml urine) + 1] values of 0.9 v. 1.75 (t = 4.45; P or = 10 years was slightly higher than that among the younger subjects. It was lowest for the heavier subjects (70% for those weighing 41-50 kg) and highest (79%) for the subjects who weighed 31-40 kg. The artesunate was well tolerated. This observation of a therapeutic effect of artesunate against S. haematobium in Nigeria confirms recent observations from Senegal. In the Adim community at least, it would be more cost-effective to treat urinary schistosomiasis with artesunate than with praziquantel. The wide-spread use of artesunate against schistosomiasis has to be considered carefully, however, if it is not to compromise the efficacy of the drug as an antimalarial, by increasing the risk of resistance developing in local Plasmodium.

Schistosomiasis--an unusual cause of ureteral obstruction: a case history and perspective

Abstract: A male, 32 years of age, presented with dysuria and abdominal pain, but no gross hematuria. He emigrated three years earlier from Somalia, East Africa, and was currently employed as a poultry processor in a rural Wisconsin community. The patient denied any trauma, sexual activity, or family history of significant illness. Abdominal and genitourinary exams were normal with negative tests for gonococcus and chlamydia. Urinalysis demonstrated microhematuria. A urogram and retrograde pyelogram revealed a mildly dilated right ureter down to the ureterovesical junction. Cystoscopy showed punctate white lesions on the bladder urothelium. Ureteroscopy was used to biopsy abnormal tissue in the distal ureter and bladder. Biopsy tissue demonstrated deposits of Schistosoma haematobium eggs. No ova were seen in collected urine specimens. The patient was successfully treated with praziquantel and will be monitored for sequelae of the disease. Schistosomiasis (Bilharziasis) can be expected to be seen with increasing frequency in the United States with the continuing influx of immigrants and refugees, as well as the return of travelers and soldiers from endemic areas. While no intermediate snail host exists for the transmission of Schistosoma sp. in the United States, the continued importation of exotic animals including snails from Africa, as well as the ability of schistosomes to shift host species warrants concern. Additionally, increasing disease associated with non-human bird schistosomes of the same genus seen in the midwestern United States is occurring throughout Europe. One should be aware that praziquantel may not always be available or effective in the treatment of schistosomiasis. It behooves the practicing clinician to remain updated on the status of this widespread zoonosis.

A survey of the prevalence of Schistosomiasis among pupils in Apata and Laranto areas in Jos, Plateau State

Abstract: Prevalence of Schistosomiasis in apparently healthy primary school pupils in Apata and Laranto areas of Jos was surveyed using 300 samples of stool and 300 samples of urine. The stool samples were processed using formol ether concentration techniques while the urine samples were processed by ordinary centrifugal sedimentation technique. The overall prevalence of urinary (Schistosoma haematobium) and intestinal (Schistosoma mansoni) schistosomiasis was 0.67%, with three samples (1% prevalence) positive for intestinal (Schistosoma mansoni) and one sample (0.33% prevalence) positive for urinary (Schistosoma haematobium) schistosomiasis respectively. Two of the three cases positive for Schistosoma mansoni were males in the age group of 11–15 years and the one positive for Schistosoma haematobium was a male patient. Prevalence in the studied area is therefore very low and immigration, sex and age dependent

Utility of Schistosoma bovis adult worm antigens for diagnosis of human schistosomiasis by enzyme-linked immunosorbent assay and electroimmunotransfer blot techniques.

Abstract: Immunodiagnostic methods based on the detection of antibodies continue to be the most effective and practical methods for the diagnosis of imported schistosomiasis. Schistosoma bovis is a species whose final natural hosts are bovines, ovines, caprines, and small wild ruminants. Different studies have demonstrated the analogies existing between S. bovis and other Schistosoma species which affect humans. The objective of this work was to evaluate the utility of S. bovis adult worm antigens (AWA) for the diagnosis of imported human schistosomiasis by enzyme-linked immunosorbent assay (ELISA) and electroimmunotransfer blotting (EITB) techniques. By detecting eggs, the ELISA for S. bovis AWA was able to definitively detect imported cases with a sensitivity of 94%. The specificity of the ELISA for S. bovis AWA was 97%. There were no differences between the results of the S. bovis AWA ELISA for patients infected with Schistosoma mansoni and those infected with Schistosoma haematobium. The EITB technique showed bands of 85, 37, and 20 kDa, which are characteristic of infections with Schistosoma spp. Specific bands to indicate infection by different species of Schistosoma have not been detected. The combined use of the ELISA for S. bovis AWA and EITB increased the global sensitivity of the study to 97%. Our findings suggest that the ELISA for S. bovis AWA is a useful test for the immunodiagnosis of imported schistosomiasis and that EITB for detecting S. bovis AWA permits the confirmation of diagnosis when the ELISA for S. bovis AWA is positive.

Efficacy of Myrrh in the treatment of schistosomiasis (haematobium and mansoni) in Ezbet El-Bakly, Tamyia Center, El-Fayoum Governorate, Egypt.

Abstract: Schistosomiasis remains a public health problem in Egypt, despite the continuous control effort. Most of the anti-schistosomal drugs have deleterious side effects or low efficacy. This necessitates a search for new safe and effective drug. A field survey was done in Ezbet El-Bakly (Tamyia Center) El-Fayoum Governorate to determine the magnitude of schistosomiasis haematobium and mansoni and to evaluate the efficacy of Mirazid (the oleo-resin extract from Myrrh of Commiphora molmol tree, family: Burseraceae) in the treatment of both types of schistosomiasis. Among the 1019 individuals parasitologically examined, the prevalence of S. haematobium and S. mansoni were 4.2% and 2.4% respectively and the geometric mean egg count (GMEC) were 33.2 eggs/10 ml urine and 113.3 eggs/gram stools. Most of the patients with haematobiasis and mansoniasis were <15 years (56.4% & 53.8%), males (56.4% & 53.8%) & illiterates (46.2% & 46.2%). All cases were treated by Myrrh (Mirazid) as two capsules (600 mg) on an empty stomach an hour before breakfast for six consecutive days and were followed up clinically and parasitologically by urine analysis by the sedimentation and nucleopore techniques and by hatching test and by stool analysis by sedimentation and Kato-Katz techniques and by hatching test. The parasitological cure rate after three months was 97.4% and 96.2% for S. haematobium and S. mansoni cases with the marvelous clinical cure without any side-effects. Patients not completely responded to a single course of treatment showed marked reduction of egg intensity. It is concluded that Mirazid proved to be safe and very effective in treatment of S. haematobium and S. mansoni infections under field conditions.

Diagnosis of urinary schistosomiasis: a novel approach to compare bladder pathology measured by ultrasound and three methods for hematuria detection.

Abstract: We aggregated published data from field studies documenting prevalence of Schistosoma haematobium infection and bladder pathology determined by ultrasonography or hematuria detected by reagent strip, questionnaire, or visual examination. A mathematical expression was used to describe the associations between prevalence of pathology/morbidity and infection. This allows for indirect comparison of these methods, which are rarely used simultaneously. All four methods showed a similar, marked association with infection. Surprisingly, ultrasound revealed higher prevalences of pathology in schools than in communities with the same prevalence of infection, implying a need for age-related cut-off values. Reagent strip testing yielded a higher prevalence than questionnaire, which in turn was higher than by visual examination. After correction for morbidity due to other causes, a consistent ratio in prevalence of hematuria of 3:2:1 resulted for the three respective methods. The simple questionnaire approach is not markedly inferior to the other techniques, making it the best option for field use.

Schistosomiasis endemic in Burkina Faso

Abstract: Burkina Faso, through the works of many teams of the OCCGE based in Bobo-Dioulasso, has signi-ficant data on several tropical endemics of which schistosomiasis. With the complementary works, it appears to be possible to establish a distribution of the schistosomiasis which reveals its importance. It will be the first stage of the planned national control program. The parasitologic data-gathering which covers the period of 1951 to 2000, used all the standard techniques. It is about Kato-Kartz and MIF for the intestinal schistosomiasis, centrifugation, filtration, serology reagent strips, macroscopy of urines and echography of the urinary system for the urinary schistosomiasis. All the eleven medical areas of the country have many sites submitted to parasitologic investigation. As regard the distribution of the two parasites involved with man (Schistosoma haematobium and S. mansoni), the data of prevalence (1% to 100%) and their distribution confirm their endemicity and the focal transmission. S. mansoni is located in eight medical areas particularly in the South and the West. S. haematobium is present in all the eleven medical areas of the country. In hydraulic planning as Sourou where the prevalences went from 23% to 70% for S. haematobium and from 0% to 69% for S. mansoni between 1987 and 1998. The situation requires a continuous monitoring. The spatial distribution of the six species of intermediate hosts shows that Bulinus truncatus and B. senegalensis Soudano-Sahelian species are present in all the ecological zones. B. globosus and Biomphalaria pfeifferi meet preferentially in the southern half of the country which reinforces the observation according to which the 14th northern parallel is often considered as the limit of septentrional extension of these two species. The other species Bulinus forskalii and B umbilicatus could have preference areas. All the species show a certain affinity with a type of biotope. The rarity and temporary aquatic systems lead to a concentration of the domestic and especially entertaining children activities around these biotopes very often contaminated. The phenomenon is amplified by the increase of contacts man-water, whose frequency and intensity are themselves dependent on activities related to hydro-agricultural planning. The analysis of the data shows, that in terms of colonization of the biotopes by molluscs and the relations between parasites and intermediate and final hosts, hydraulic planning turns out to be an amplifying factor of the species proliferation and parasitic flux host-parasite.

Urinary schistosomiasis in Zimbabwean school children: predictors of morbidity.

Abstract: Background: The morbid effects of urinary bilharziasis are becoming more evident with the advent of sophisticated diagnostics such as ultrasound. However, such diagnosis of Schistosoma haematobium morbidity is often hampered by lack of funds, proper equipment, or training. Objective: We performed a cross-sectional investigation of schoolchildren in a highly endemic area of east central Zimbabwe in order to assess the utility of a number of simple clinical indicators to predict Schistosoma haematobium morbidity. Methods: Prevalence and intensity of S. haematobium infection was determined in 551 schoolchildren, with ultrasound examination of the kidneys and bladder performed on 222. The association of a number of demographic, parasitological, and clinical parameters with clinical outcome was evaluated. Results: Overall, 60% of the children were infected with S. haematobium. Although lacking specificity, proteinuria and parasite eggs count best predicted bladder pathology. Presence of kidney dilation was associated with fatigue and pain upon urination, but these variables were not very sensitive. Conclusions: None of the variables assessed were ideal predictors of morbidity. However, the results suggest that a combination of inexpensive, simple indicators may allow for improved targeting of S. haematobium treatment to those with severe morbidity and better monitoring of the progress of control campaigns when more expensive diagnostic methods are not available. African Health Sciences 2004; 4(2): 115-118

Female genital schistosomiasis: case report and review of the literature.

Abstract: A 37-year-old woman, originally from South Africa, presented for a gynecologic examination. Speculum examination revealed a friable cervical lesion. Both the cervical smear and biopsy contained intact, viable schistosome eggs consistent with those of Schistosoma haematobium. Appropriate treatment was initiated promptly, avoiding significant morbidity. The diagnosis of female genital schistosomiasis must be considered when the patient has a history of travel to or residence in endemic areas.

[Long-term impact of a mass treatment by praziquantel on morbidity due to Schistosoma haematobium in two hyperendemic villages of Niger]

Abstract: Although it is established that the treatment by praziquantel reduces the urinary lesions due to Schistosoma haematobium, the frequency of mass treatment necessary to maintain a low morbidity level remains poorly known. The objective of this work was to study the impact over three years of a single praziquantel mass treatment on schistosomiasis morbidity in two different systems of disease transmission in Niger. The study was performed in 2 villages hyperendemic for schistosomiasis in the South-West of Niger presenting respectively 2 different systems of schistosomiasis transmission: Koutoukale-Zeno (K Zeno), located close to an irrigated area of the Niger River Valley where the transmission is permanent, and Teguey located along a temporary pond where the transmission is seasonal. After the initial evaluation (1994), we carried out a survey 3 years later (1997) except in K. Zeno where an intermediate evaluation was performed 10 months after the initial survey (1995). Approximately 300 randomised people have been examined as follows: macroscopic examination of urine and reagent sticks for macro- and micro-haematuria, filtration and microscopic examination of urine for Schistosoma eggs, and ultrasound scan of the urinary tract for morbidity. The therapeutic coverage has reached 69.9% in K. Zeno and 78.2% in Teguey. The prevalence of infestation decreased from 74.1% to 56.4 % in K. Zeno (p or = 50) went in the same time from 9.9% to 12.8% (p = 0.3) in K. Zeno and from 9.1% to 3.3% in Teguey (p = 0.01). Using ultrasound scan, the prevalence of the bladder lesions reached its previous level in both villages. However the prevalence of hydronephrosis decreased from 21.1% to 3.9% in K. eno (p < 0.001) and from 12.6% to 4.2% in Teguey (p < 0.001). Three years after the single mass treatment, the morbidity did not reach the initial level. The effectiveness of the treatment is better in the pond system where the transmission is seasonal. The lesions of the upper tract decreased more slowly than the bladder lesions, but a long time after the treatment. The re-infestation induced the re-appearance of the bladder lesions sooner than the lesions of the upper tract. The periodicity of the treatment should be variable according to the transmission system. It should occur every 2 years in irrigated areas and could be delayed (3 years) in temporary ponds. The control was beneficial in the pond system and induced a significant reduction of the severe lesions.

Applicability of a monoclonal antibody-based dipstick in diagnosis of urinary schistosomiasis in the Central Region of Ghana.

Abstract: Summary We tested a rapid visually read monoclonal antibody (MoAb) based dipstick assay for specific diagnosis of urinary schistosomiasis against microscopy and the use of haematuria and proteinuria in a schistosomiasis haematobia endemic area in the Central Region of Ghana. The study group consisted of 141 school children (83 males, 58 females) aged 8-19 years. A total of 129 of 141 (91.5%) submitted stool samples, and 7.8% had Schistosoma mansoni, 55% had hookworms and 6.2% had tapeworms. The presence of S. mansoni and intestinal parasites did not appear to influence the results of the MoAb-dipstick assay. The urinary schistosomiasis prevalence by MoAb-dipstick (78%) was higher (P < 0.05) than the estimate by microscopy (60.3%), microhaematuria (27%) and proteinuria (30.5%). The MoAb-dipstick correctly identified 98.8% of microscopically confirmed cases and missed one (1.3%). The dipstick was also positive for 26 of 56 (46.4%) egg-negative individuals, thereby giving a sensitivity of 98.8% and a specificity of 53.6%. On the other hand, microhaematuria and proteinuria were 38.8% and 30.6% sensitive, and 91.1% and 69.6% specific, respectively. Microhaematuria and proteinuria were less sensitive (P < 0.05) than both microscopy and MoAb-dipstick.

The prevalence, intensity and clinical signs of urinary schistosomiasis in Imo state, Nigeria.

Abstract: Urine samples were assayed for urinary schistosomiasis in four local government areas (LGA) of Imo State, Nigeria between May 1998 and September 2000. A total of 3504 persons were sampled, with 880 (25.1%) being positive for urinary schistosomiasis, based on records of eggs of Schistosoma haematobium. The prevalence of S. haematobium infection differed in the various LGAs, with Oguta (38.9%) and Owerri-West (10.4%) showing the highest and the lowest values, respectively. Prevalence was higher in males (67.4%) than in females (32.6%) and in subjects 11-20 years of age (31.5%), while prevalence varied among different occupational groups, with farmers ranking the highest (41.6%). Visible haematuria was the predominant symptom (P < 0.05). Of 880 persons positive for eggs of S. haematobium, 452 (51.4%) had visible haematuria, followed by suprapubic pains 214 (24.3%) and painful micturition 97 (11.0%). Although 367 (10. 5%) of the sampled subjects with eggs of S. haematobium showed no visible haematuria, 513 (14.6%) clearly demonstrated haematuria.

[Bulinus truncatus, intermediate host of Schistosoma haematobium in the Senegal River Basin (SRB)].

Abstract: Une etude des relations entre Bulinus truncatus et Schistosoma haematobium a ete effectuee dans le bassin du fleuve Senegal (BFS) pour evaluer le role de B. truncatus dans la transmission de la schistosomose urinaire au Senegal. Les tests de compatibilite montrent une susceptibilite de B. truncatus a l'infestation par S. haematobium dans la Haute vallee du BFS. Le suivi malacologique revele la presence de B. truncatus naturellement infestes dans la Moyenne vallee. En outre, l'identification de l'espece S. haematobium chez ces bulins par la technique du Single Strand Conformational Polymorphism (SSCP) confirme la participation de B. truncatus dans la dynamique de transmission.

Measuring schistosomiasis case management of the health services in Ghana and Mali.

Abstract: The World Health Organization recommends passive case detection by regular health services as a minimum strategy for schistosomiasis morbidity control. To evaluate preparedness of the health systems in Ghana and Mali, we presented four clinical scenarios, two with blood in urine (main early symptom of Schistosoma haematobium) and two with (bloody) diarrhoea (main early symptom of S. mansoni), to health workers. We requested the health personnel for an initial diagnosis and case management strategy without providing information about our primary interest in schistosomiasis. The information was used to determine the chance that a person reporting with symptoms that might have been caused by schistosomiasis would receive praziquantel. All selected health workers participated. Their initial diagnosis was frequently S. haematobium for both scenarios with blood in urine. For the two scenarios with (bloody) diarrhoea, only few mentioned S. mansoni. At health centre level, case management in Mali mainly consisted of direct prescription of medication, whereas in Ghana health workers often referred to a hospital or requested a diagnostic test. The ultimate probability of prescribing praziquantel was relatively high for the scenarios with blood in urine, 60% in Ghana and 75% in Mali, but very low for both scenarios with (bloody) diarrhoea (<20%). Of those health care facilities that would prescribe praziquantel, 60% (Ghana) and 80% (Mali) had it in stock. In conclusion, the clinical scenario study showed that patients reporting with blood in urine will be treated with praziquantel at approximately half of the health care facilities, whereas of those presenting with (bloody) diarrhoea only few would receive treatment with praziquantel. Considering these facts, it is questionable if passive case detection is a sufficient basis for effective schistosomiasis morbidity control, especially for S. mansoni infection.

Prevalence of parasitic diseases among nomadic Fulanis of south-eastern Nigeria.

Abstract: A study was carried out to determine the prevalence of parasitic infections among the nomadic Fulanis of south-eastern Nigeria between September 2003-March 2004. Urine, stool and blood specimens were collected from each of 231 subjects. Of these, 98 (42.4%) were infected with one or more of 14 parasitic species, of which Plasmodium malariae had the highest prevalence (15.3%). Others included 6 intestinal helminth parasites: Ascaris lumbricoides, hookworm, Strongyloides stercoralis, Schistosoma mansoni, Enterobius vermicularis, Trichocephalus trichiurus, 2 protozoan parasites: Entamoeba histolytica and E. coli, 4 blood parasites: Mansonella perstans, Loa loa, Trypanosoma sp, Plasmodium falciparum, as well as Schistosoma haematobium recovered in the urine. Prevalence of these parasitic infections varied significantly among bush encampments, sexes, and age groups. They had evidence of onchocerciasis. Their occupational imperatives, beliefs and general life style are contributing factors to the prevalence of parasitic infections among the nomadic Fulanis of south eastern Nigeria. Aspects of prevalence and control of parasitic infections are discussed.

Emergence of Schistosoma mansoni in the Niger River valley, Niger.

Abstract: Urinary and intestinal schistosomiasis are both endemic in Niger with a dominance of Schistosoma haematobium. This study pointed out the appearance of the infection to S. mansoni in the Niger River valley, where it was until then unknown in Niger. In one year the prevalence increased from 5.9 to 19.5%.

Quantitative evaluation of integrated schistosomiasis control: the example of passive case finding in Ghana.

Abstract: Summary Passive case finding based on adequate diagnosis and treatment of symptomatic individuals with praziquantel by the health care facilities is a minimum requirement for integrated schistosomiasis control. Two field studies were conducted in Ghana to obtain quantifications about the steps in this process: (1) a study of health-seeking behaviour through interview of individuals with reported schistosomiasis-related symptoms; (2) a study of the performance of the Ghanaian health system with regard to schistosomiasis case management by presenting clinical scenarios to health workers and collecting information about availability of praziquantel. It appeared that cases of blood in urine (the most typical symptom of Schistosoma haematobium) and blood in stool (the most typical symptom of S. mansoni) have a very small probability of receiving praziquantel (4.4% and 1.4%, respectively) from health facilities. Programmes aimed at making the drug available at all levels of the health care delivery system and encouraging health-seeking behaviour through health education are not likely to increase these probabilities beyond 30%. This is because many cases with blood in urine do not consider it serious enough to seek health care, and blood in stool usually requires (imperfect) diagnostic testing and referral. We therefore conclude that additional control activities, especially for high-risk groups, will remain necessary.

Funiculitis due to Schistosoma haematobium: uncommon diagnosis using parasitologic analysis of semen.

Abstract: Schistosomal funiculitis is one of the rare localizations of longstanding chronic infection with schistosomiasis. We report a case of a 24-year-old-man who experienced iliac fossa pain and weight loss eight years after his last trip to Mali. Clinical diagnosis of lesions in the genitourinary tract due to schistosomiasis and biologic analysis are required to diagnose this uncommon localization of schistosomiasis.