High prevalence of Schistosoma mansoni in six health areas of - Kasansa health zone, Democratic Republic of the Congo: short report.
ABSTRACT: School-aged children suffer the most from schistosomiasis infection in sub Saharan Africa due to poverty and limited sanitary conditions. Mapping of disease burden is recommended and there is a need of updating prevalence data which is as old as 20 years in the Democratic Republic of Congo. An epidemiological and parasitological study was carried out in 2011 in the health zone of Kasansa. Six health areas (HA) were included in the study. In each health area, one primary school was selected. School-aged children were screened for S. mansoni infection using parallel Kato-Katz and direct microscopy techniques. A total of 335 school-aged children were screened. The average prevalence was 82.7% and ranged between 59.5-94.9%. Four of the six HAs had a prevalence level over 91%. Of all infected children, about half 112 (43.2%) had light parasite density. These results demonstrate that Schistosoma mansoni infection is a bigger problem than anticipated and there is an urgent need to implement effective control measures.
Project description:Despite growing evidence that infants and very young children can be infected with schistosomes, the epidemiological features and risk factors are not well described in this age group. We aimed to assess the prevalence of S. mansoni infection in children under two years of age from a population with a known high burden of infection in school-aged children and adults and thus inform the need for interventions in this potentially vulnerable age group. In a cross-sectional study in Mbita Sub-county, along the east coast of Lake Victoria, Western Kenya, we enrolled 361 children aged 6-23 months. The prevalence of S. mansoni infection was detected using the Kato-Katz stool examination and a point-of-care test for urinary circulating cathodic antigen (POC-CCA) (Rapid Medical Diagnostics, Pretoria, South Africa). Three-hundred and five (305) children had complete data of whom 276 (90.5%, 95%CI: 86.6-93.5) children were positive for S. mansoni by the POC-CCA test, while 11 (3.6%, 95%CI: 1.8-6.4) were positive by the Kato-Katz method. All Kato-Katz positive cases were also positive by the POC-CCA test. In multivariable analysis, only geographical area, Rusinga West (AOR = 7.1, 95%CI: 1.4-35.2, P = 0.02), was associated with S. mansoni infection using Kato-Katz test. Independent associations for POC-CCA positivity included age, (12-17 months vs 6-11 months; AOR = 7.8, 95%CI: 1.8-32.6, P = 0.002) and breastfeeding in the previous 24 hours (AOR = 3.4, 95%CI: 1.3-9.0, P = 0.009). We found a potentially very high prevalence of S. mansoni infection among children under two years of age based on POC-CCA test results in Mbita Sub-county, Kenya, which if confirmed strongly supports the need to include infants in public health strategies providing universal prophylactic treatment in high burden settings. Further research is required to determine the accuracy of diagnostic tools to detect light infection among very young children and possible long-term health impacts.
Project description:<h4>Background</h4>Schistosoma mansoni, causing intestinal schistosomiasis, is widely distributed in Ethiopia and new transmission foci are continually reported. Here we report new transmission sites and prevalence of S.mansoni infection among school children in Yachi areas, southwestern Ethiopia.<h4>Methods</h4>A cross-sectional survey was conducted among school children of Yachi Yisa and Yachi Efo elementary schools, southwestern Ethiopia, from April 2017 to June 2017. Three hundred seventeen school children aged six to 15 years were randomly selected to provide stool specimens for helminth infection examination by Kato-Katz and formol-ether concentration techniques. Snail survey was carried out to assess schistosome infection in Biomphalaria pfeifferi. Laboratory bred mice were also exposed to schistosome cercariae shed by B. pfeifferi en masse for definite identification of Schistosoma species.<h4>Results</h4>From the 317 stool specimens examined using double Kato-Katz thick smear and single formol-ether concentration techniques, 224 (70.7%) were found positive for at least one intestinal helminth species. The most prevalent parasite was S. mansoni (42.9%) followed by Trichuris trichiura (34.1%) and Ascaris lumbricoides (14.2%). The prevalence of S. mansoni infection was significantly higher among the children attending Yachi Yisa School (49.4%) than those in Yachi Efo School (35.6%) (P?=?0.002). The study also revealed that there was a significantly higher prevalence of S.mansoni infection among males (51.2%) than females (33.1%) (P?<?0.001). However, the prevalence of S.mansoni infection was not significantly associated with age categories (P?=?0.839). B. pfeifferi snails infected with schistosomes were collected from the water bodies found in the study area. After six weeks post exposure, adult S. mansoni worms were harvested from the mesenteric veins of laboratory bred mice.<h4>Conclusions</h4>The study revealed establishment of new S. mansoni transmission foci and moderate prevalence of schistosomiasis in Yachi areas. Hence, treatment of all school-age children once every two years is recommended. Snail control and non-specific control approaches including provision of clean water supply and health education should also complement mass drug administration of praziquantel.
Project description:BACKGROUND:Schistosomiasis is one of the most neglected tropical parasitic disease which is common in Ethiopia. It is disease of rural areas for decades but now days there are reports of schistosomiasis from urban settings. Therefore, this study aimed to determine epidemiology of Schistosoma mansoni (S. mansoni) infection and associated determinant factors among school children attending primary schools nearby rivers in Jimma town, an urban setting, southwest Ethiopia. METHODOLOGY:A cross sectional study was conducted among 328 school children aged between 7-17 years in selected primary schools nearby rivers in Jimma town from March to April 2017. For the diagnosis of S. mansoni, a single stool sample was obtained from each child and processed using double Kato Katz thick smear for quantification of S. mansoni ova examined using light microscope. A questionnaire was used to collect socio demographic data and associated determinant factors for S. mansoni infection. Data were analyzed using SPSS version 20.0. Variables with P-value < 0.05 were significantly associated with S. mansoni infection. RESULTS:The overall prevalence of S. mansoni infection was found to be 28.7%. Majority of infection intensities were categorized as light with maximum egg per gram of stool (epg) was 1728. The geometric mean of infection intensity was 102.3epg. Schools distance from river (p = 0.001), swimming habit in rivers (p = 0.001) and crossing river on bare foot (p = 0.001) were independent risk factors for S. mansoni infection. CONCLUSIONS:The study revealed S. mansoni infection is prevalent in Jimma town. The school children were at moderate risk of morbidity caused by S. mansoni (prevalence ? 10% and < 50% according to WHO threshold), hence a biannual mass drug administration with praziquantel is required once every two years in the study area and promote health information on prevention, control, transmission and risk factors for S. mansoni infection.
Project description:BACKGROUND:Schistosoma mansoni (S. mansoni) infection is a significant public health problem in Ethiopia, and has wide distribution in the country. The impact of the disease is particularly high on school-age children. Nationwide 385 endemic districts were identified, whereby control and elimination interventions are underway using school-based annual mass drug administration (MDA) with praziquantel. The national elimination program targets endemic districts as a whole. The aim of this study was to identify the transmission foci of Schistosoma mansoni and determine prevalence of soil-transmitted helminths (STHs) in Abeshge district. METHODS:The study was conducted from April to May, 2019 among school-age children randomly selected from public elementary schools in Abeshge district, South-central Ethiopia. Demographic information and data on risk factors of S. mansoni infection were gathered using pre-tested questionnaire. Moreover, a stool sample was collected from each child and examined using Kato-Katz thick smear technique. The data were analyzed using STATA_MP version 12. RESULTS:A total of 389 school-age children from five public elementary schools were included in the study. The overall prevalence of S. mansoni and STHs was 19.3% (75/389) and 35% (136/389), respectively. The prevalence of S. mansoni was 60.6% in Kulit Elementary school, while it was zero in Geraba. The prevalence of S. mansoni was significantly higher among males (AOR?=?2.6, 95% CI 1.3-5.1), those with habit of swimming and/or bathing in rivers (AOR?=?2.9, 95%CI 1.3-5.1) and involved in irrigation activities (AOR?=?2.9, 95% CI 1.0-8.3). Overall, the prevalence of S. mansoni was significantly higher among school children attending Kulit Elementary School compared to those attending the remaining schools (AOR?=?12.5, 95%CI 6.2-25.1). CONCLUSION:A wide variation of S. mansoni prevalence was observed among the school children in the different schools. Control interventions better identify and target foci of S. mansoni transmission, instead of targeting the district homogenously.
Project description:Intestinal parasite infections are major public health problems of children in developing countries causing undernutrition, anemia, intestinal obstruction and mental and physical growth retardation. This study was conducted to assess the prevalence of intestinal helminthic infections among children under five years of age with emphasis on Schistosoma mansoni in Wonji Shoa Sugar Estate, Ethiopia. A cross-sectional parasitological survey was conducted in under-five children living in Wonji Shoa Sugar Estate Ethiopia, April, 2013. Stool samples were collected and examined for intestinal parasites using single Kato-Katz and single Sodium acetate-acetic acid-formalin (SAF) solution concentration methods. Out of 374 children examined using single Kato-Katz and single SAF-concentration methods, 24.3% were infected with at least one intestinal parasite species. About 10.4%, 8.8%, 4.6%, 2.9%, 1.6% and 0.8% of the children were infected with Hymenolepis nana, Schistosoma mansoni, Ascaris lumbricoides, Trichuris trichiura, Enterobius vermicularis and hookworm, respectively. Prevalence of double, triple and quadruple intestinal helminthic infection was 6.4%, 0.54% and 1.1%, respectively. A significant increase in prevalence of S. mansoni (8.3% versus 3.2%) and T. trichiura (2.7% versus 0.5%) infection was observed when determined via the single Kato-Katz method compared to the prevalence of the parasites determined via the single SAF-concentration method. On the other hand, the single SAF-concentration method (9.1%) revealed a significantly higher prevalence of H. nana infection than the single Kato-Katz (1.6%) does. In conclusion, intestinal helminths infections particularly S. mansoni and H. nana were prevalent in under-five children of Wonji Shoa Sugar Estate. Including praziquantel treatment in the deworming program as per the World Health Organization guidelines would be vital to reduce the burden of these diseases in areas where S. mansoni and H. nana infections are prevalent among under-fives. Kato-Katz can be used in estimating the prevalence of S. mansoni and other helminth infections.
Project description:<h4>Background</h4>In Ghana, pre-school-aged children (PSAC) are at risk of intestinal schistosomiasis and are living in need of praziquantel treatment. To better assess the infection burden within this vulnerable demographic group, we have provided a comparative assessment of the prevalence of Schistosoma mansoni in pre-school-aged children by urine circulating cathodic antigen (CCA) dipsticks, real-time PCR Taqman® faecal assays and Kato-Katz coproscopy.<h4>Methods</h4>In all, 190 pre-school-aged children were sampled from three endemic communities (viz. Tomefa, Torgahkope/Adakope, and Manheam) around Weija dam, Southern Ghana. Fresh stool and urine samples were collected from all participants for diagnosis.<h4>Results</h4>Among all the three communities, the urine-CCA assay recorded the highest prevalence values of 90.5% (95% CI 80.4-96.4), 87.9% (95% CI 76.7-95), and 81.2% (95% CI 69.9-89.6) in Tomefa, Torgahkope/Adakope, and Manheam respectively. Prevalence by real-time PCR was 50% (95% CI 35.5-64.5), 8% (95% CI 2.2-19.2) and 16.7% (95% CI 8.3-28.5), while by Kato-Katz was 55.6% (95% CI 42.5-68.1), 8.6% (95% CI 2.9-19) and 11.6% (95% CI 5.1-21.6) respectively. Children aged 1?year and over were found to be positive with the urine-CCA assay; by the ages of 3-4, over 50% were urine-CCA patent. The sensitivity and specificity of the POC-CCA dipsticks, when compared against the combined results of Kato-Katz/TaqMan results was found to be 84.1% (95% CI?=?72.7-92.1) and 12.9% (95% CI?=?6.6-22) respectively.<h4>Conclusions</h4>We propose that the urine-CCA dipstick may be a useful rapid diagnostic tool to estimate the prevalence of intestinal schistosomiasis in PSAC, particularly in rapid identification of at-risk areas. However, our assessment has shown that it possible to record false positives when compared to combined Kato-Katz and qPCR results. To guide PSAC praziquantel treatment needs, we propose the urine CCA assay should be included in routine surveillance of intestinal schistosomiasis alongside other diagnostics such as Kato-Katz and urine filtration.
Project description:Schistosomiasis is one of the major Neglected Tropical Diseases (NTDs) in sub-Saharan Africa. In sub-Saharan Africa, two major human schistosome species namely Schistosoma mansoni and S. haematobium often occur sympatrically largely affecting children. Recognizing the public health impact of Schistosomiasis, the World Health Organization (WHO) is urging member states to regularly treat at least 75% and up to 100%, of all school-aged children at risk of morbidity. For control strategies based on targeted mass drug administration (MDA) to succeed it is essential to have a simple and sensitive test for monitoring the success of these interventions. Current available diagnostic tests, such as egg detection in stool by Kato-Katz (KK) for S. mansoni and detection of eggs or blood (hematuria) in urine for S. haematobium have reduced sensitivity in low intensity settings. The objective of the study was to evaluate active single or duo schistosome infections in school children following MDA using molecular diagnostics (PCR) on filtered urine samples and comparing that against traditional diagnostic tests. This cross-sectional study was conducted among 111 school children aged 7-15 years in Chongwe and Siavonga Districts in Zambia. Species-specific cell-free repeat DNA fragment were amplified from 111 filtered urine samples. Our approach detected eight times more positive cases (total 77) than by KK (9) for S. mansoni and six times more (total 72) than by hematuria (11) for S. haematobium and even more against urine filtration (77 compared to only 6). The same pattern was observed when stratified for age group and sex specific analysis with 100% sensitivity and specificity devoid of any cross amplification. In addition, 69 individuals (62%) were co-infected by both parasites. We have demonstrated a significantly higher prevalence of both species than indicated by the traditional tests and the persistent maintenance of reservoir of infection after MDA. Our approach is an effective means of detecting low intensity infection, which will enhance the effectiveness of surveillance and assess the impact of MDA control programs against schistosomiasis.
Project description:AbstractFollowing implementation of the national control program, a reassessment of Schistosoma mansoni prevalence was conducted in Burundi to determine the feasibility of moving toward elimination. A countrywide cluster-randomized cross-sectional study was performed in May 2014. At least 25 schools were sampled from each of five eco-epidemiological risk zones for schistosomiasis. Fifty randomly selected children 13-14 years of age per school were included for a single urine-circulating cathodic antigen (CCA) rapid test and, in a subset of schools, for duplicate Kato-Katz slide preparation from a single stool sample. A total of 17,331 children from 347 schools were tested using CCA. The overall prevalence of S. mansoni infection, when CCA trace results were considered negative, was 13.5% (zone range [zr] = 4.6-17.8%), and when CCA trace results were considered positive, it was 42.8% (zr = 34.3-49.9%). In 170 schools, prevalence of this infection determined using Kato-Katz method was 1.5% (zr = 0-2.7%). The overall mean intensity of S. mansoni infection determined using Kato-Katz was 0.85 eggs per gram (standard deviation = 10.86). A majority of schools (84%) were classified as non-endemic (prevalence = 0) using Kato-Katz; however, a similar proportion of schools were classified as endemic when CCA trace results were considered negative (85%) and nearly all (98%) were endemic when CCA trace results were considered positive. The findings of this nationwide reassessment using a CCA rapid test indicate that Schistosoma infection is still widespread in Burundi, although its average intensity is probably low. Further evidence is now needed to determine the association between CCA rapid test positivity and low-intensity disease transmission.
Project description:BACKGROUND:The World Health Organization recommends that schistosomiasis be treated through Mass Drug Administration (MDA). In line with this recommendation, Zimbabwe commenced a national helminth control program in 2012 targeting schoolchildren throughout the country for 6 years. This study, part of a larger investigation of the impact of helminth treatment on the overall health of the children, determined the effect of annual praziquantel treatment on schistosome infection and morbidity in a cohort of children during Zimbabwe's 6-year national helminth control program. METHODOLOGY/PRINCIPAL FINDINGS:A school-based longitudinal study was carried out in 35 sentinel sites across Zimbabwe from September 2012 to November 2017. The sentinel sites were selected following a countrywide survey conducted in 280 primary schools. Schistosoma haematobium was diagnosed using the urine filtration technique. Schistosoma mansoni was diagnosed using both the Kato-Katz and formol-ether concentration techniques. S. haematobium morbidity was determined through detection of macro and microhaematuria. A cohort of children aged 6-15 years old was surveyed annually before MDA and 6 weeks post treatment. Maximum treatment coverage reached 90% over the 6 rounds of MDA. At baseline S. haematobium infection prevalence and intensity were 31.7% (95% CI = 31.1-32.2) and 28.75 eggs/10ml urine (SEM = 0.81) respectively, while S. mansoni prevalence and intensity were 4.6% (95% CI = 4.4-4.8) and 0.28 eggs/25mg (SEM = 0.02). Prior to the 6th round of MDA, S. haematobium infection prevalence had reduced to 1.56% (p<0.001) and infection intensity to 0.07 (SEM 0.02). Six weeks later after the 6th MDA, both were 0. Similarly the prevalence of S. haematobium morbidity as indicated by haematuria also fell significantly from 32.3% (95% CI = 29.9-34.6) to 0% (p< 0.0001) prior to the final MDA. For S.mansoni, both prevalence and intensity had decreased to 0 prior to the 6th MDA. After 6 rounds of annual MDA, prevalence and intensity of both schistosome species decreased significantly to 0% (p< 0.0001). CONCLUSION:Zimbabwe's helminth control program significantly reduced schistosome infection intensity and prevalence and urogenital schistosomiasis morbidity prevalence in a cohort of school-aged children, moving the schistosome prevalence in the children from moderate to low by WHO classification. These findings will inform the design of the country's next stage interventions for helminth control and eventual elimination.
Project description:Anaemia reduces cognitive potential in school children, retards their growth and predisposes them to other diseases. As there is a paucity of data on the current burden of P. falciparum, S. mansoni and soil transmitted helminths (STH) infections and their correlation with schoolchildren's anemia in the Democratic Republic of Congo (DRC), we collect these data.This study reports baseline data collected from a randomized controlled trial investigating the impact of IPT with SP and SP-PQ on anemia and malaria morbidity in Congolese schoolchildren (Trial registration: NCT01722539; PACTR201211000449323). S. mansoni and STH infections were assessed using kato-katz technique. Malaria infection and hemoglobin concentration were assessed using Blood smear and Hemocontrol device, respectively.A total of 616 primary schoolchildren from 4 to 13 years old were enrolled in the study. The prevalence of Plasmodium spp. infection was 18.5% (95%CI:15.6-21.9). Amongst those infected, 24 (21%), 40 (35.1%), 40 (35.1%), 10 (8.8%), had light, moderate, heavy, very high malaria parasite density, respectively. Above 9 years of age (p = 0.02), male and history of fever (p = 0.04) were both associated with malaria infection. The overall prevalence of S. mansoni infection was 6.4% (95%CI:4.4-9.1). Girls were associated with S. mansoni infection (p = 0.04). T. trichiura was the most prevalent STH infection (26.3%), followed by A. lumbricoides (20.1%). Co-infection with malaria-S. mansoni and malaria-STH was, respectively, 1.5% (CI95%:0.7-3.3) and 6.4% (CI95% 4.4-9.1). The prevalence of anemia was found to be 41.6% (95%CI:37.7-45.6) and anemia was strongly related with Plasmodium ssp infection (aOR:4.1; CI95%:2.6-6.5;p<0.001) and S. mansoni infection (aOR:3.3;CI95%:1.4-7.8;p<0.01).Malaria and S. mansoni infection were strongly associated with high prevalence of anemia in schoolchildren. Therefore, specific school-based interventions, such as intermittent preventive treatment or prophylaxis, LLITN distribution, anthelminthic mass treatment and micronutrient supplementation are needed to improve school children's health.