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BACKGROUND: Neglected tropical diseases (NTDs), including soil-transmitted helminths (STHs) and schistosomiasis, continue to impose a heavy burden, especially in sub-Saharan Africa and Uganda, despite being preventable. Integration of NTD management into primary healthcare has been inadequate. While researchers have explored community perspectives, there is a notable gap in understanding the viewpoints of healthcare workers (HCW), which is crucial for effective NTD control strategies. This study explores HCW' perspectives in Eastern Uganda, highlighting challenges in schistosomiasis and STH prevention and management. METHODS: In this qualitative descriptive study, we conducted semistructured interviews with 10 key informants who were HCW in Eastern Uganda with experience in managing STHs and schistosomiasis. Participants were selected purposively and interviewed through Zoom guided by a comprehensive interview guide. The data were transcribed, coded and analyzed thematically. RESULTS: We identified five key themes regarding the impact and management of NTDs: (i) the burden of NTDs, where schistosomiasis and STHs were notably prevalent among children and communities adjacent to water bodies; (ii) transmission of NTDs, emphasizing water bodies and poor sanitation as primary routes of disease spread; (iii) clinical manifestations of NTDs, detailing the symptomatic presentations that complicate diagnosis and management; (iv) challenges in managing and diagnosing NTDs, highlighting the shortages of essential medications and diagnostic tools, along with the under-prioritization of NTDs within healthcare systems; and (v) fatalities and complications arising from NTDs, reporting on the severe outcomes and under-reporting of deaths associated with NTDs due to misdiagnosis, delayed treatment and traditional healing preferences. CONCLUSION: The interviewed Ugandan HCW demonstrated sufficient knowledge of schistosomiasis and STHs, but faced challenges due to inadequate diagnostic tools and medication shortages. The study underscores the need for NTD prioritization with direct funding and government involvement, alongside strategies that integrate continuous medical training, effective community outreach and an enhanced healthcare system response to reduce the burden of NTDs.
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Smooth muscle cells (SMCs), Interstitial cells of Cajal (ICC) and Platelet-derived growth factor receptor α positive (PDGFRα+) cells form an integrated, electrical syncytium within the gastrointestinal (GI) muscular tissues known as the SIP syncytium. Immunohistochemical analysis of gastric corpus muscles showed that c-KIT+/ANO1+ ICC-IM and PDGFRα+ cells were closely apposed to one another in the same anatomical niches. We used intracellular microelectrode recording from corpus muscle bundles to characterize the roles of intramuscular ICC and PDGFRα+ cells in conditioning membrane potentials of gastric muscles. In muscle bundles, that have a relatively higher input impedance than larger muscle strips or sheets, we recorded an ongoing discharge of stochastic fluctuations in membrane potential, previously called unitary potentials or spontaneous transient depolarizations (STDs) and spontaneous transient hyperpolarizations (STHs). We reasoned that STDs should be blocked by antagonists of ANO1, the signature conductance of ICC. Activation of ANO1 has been shown to generate spontaneous transient inward currents (STICs), which are the basis for STDs. Ani9 reduced membrane noise and caused hyperpolarization, but this agent did not block the fluctuations in membrane potential quantitatively. Apamin, an antagonist of small conductance Ca2+-activated K+ channels (SK3), the signature conductance in PDGFRα+ cells, further reduced membrane noise and caused depolarization. Reversing the order of channel antagonists reversed the sequence of depolarization and hyperpolarization. These experiments show that the ongoing discharge of STDs and STHs by ICC and PDGFRα+ cells, respectively, exerts conditioning effects on membrane potentials in the SIP syncytium that would effectively regulate the excitability of SMCs.
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Células Gigantes , Células Intersticiales de Cajal , Potenciales de la Membrana , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas , Animales , Células Intersticiales de Cajal/fisiología , Células Intersticiales de Cajal/metabolismo , Ratones , Potenciales de la Membrana/fisiología , Células Gigantes/metabolismo , Células Gigantes/fisiología , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/metabolismo , Anoctamina-1/metabolismo , Estómago/fisiología , Estómago/citología , Miocitos del Músculo Liso/metabolismo , Miocitos del Músculo Liso/fisiología , Proteínas Proto-Oncogénicas c-kit/metabolismo , Masculino , Ratones Endogámicos C57BLRESUMEN
Canine soil-transmitted helminths (STHs) cause important zoonoses in the tropics, with varying degrees of intensity of infection in humans and dogs. This study aimed to investigate the prevalence and associated risk factors for STHs in community dogs residing in Grenada, West Indies. In May 2021, 232 canine fecal samples were examined for zoonotic helminths by microscopy (following flotation), and genomic DNA from a subset of 211 of these samples were subjected to multiplex qPCR for the detection and specific identification of hookworms, Toxocara spp. and Strongyloides. Microscopic examination revealed that 46.5% (108/232, 95% CI 4052.9), 9% (21/232, 95% CI 5.3512.7) and 5.2% (12/232, 95% CI 2.38) of the samples contained eggs of Ancylostoma spp., Toxocara spp. and Trichuris vulpis, respectively. Multiplex qPCR revealed that, 42.2% (89/211, 95% CI 35.548.8) were positive for at least 1 zoonotic parasite. Of these, 40.8% (86/211, 95% CI 34.147.3) of samples tested positive for Ancylostoma spp., 36% (76/211, 95% CI 29.542.9) were positive for A. caninum, 13.3% (28/211, 95% CI 918.6) for A. ceylanicum, 5.7% for T. canis (12/211, 95% CI 2.978.81) and 1% (2/211, 95% CI 02.26) for Strongyloides spp. (identified as S. stercoralis and S. papillosus by conventional PCR-based Sanger sequencing). Using a multiple logistic regression model, a low body score and free-roaming behaviour were significant predictors of test-positivity for these parasitic nematodes in dogs (P < 0.05). Further studies of zoonotic STHs in humans should help elucidate the public health relevance of these parasites in Grenada.
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Enfermedades de los Perros , Helmintos , Animales , Perros , Humanos , Ancylostoma , Enfermedades de los Perros/epidemiología , Enfermedades de los Perros/parasitología , Heces/parasitología , Grenada/epidemiología , Helmintos/clasificación , Helmintos/genética , Prevalencia , Factores de Riesgo , Toxocara , Zoonosis/epidemiologíaRESUMEN
Malaria, caused by the Plasmodium species, is an infectious disease responsible for more than 600 thousand deaths and more than 200 million morbidity cases annually. With above 90% of those deaths and cases, sub-Saharan Africa is affected disproportionately. Malaria clinical manifestations range from asymptomatic to simple, mild, and severe disease. External factors such as the gut microbiota and helminthiases have been shown to affect malaria clinical manifestations. However, little is known about whether the gut microbiota has the potential to influence malaria clinical manifestations in humans. Similarly, many previous studies have shown divergent results on the effects of helminths on malaria clinical manifestations. To date, a few studies, mainly murine, have shown the gut microbiota's capacity to modulate malaria's prospective risk of infection, transmission, and severity. This short review seeks to summarize recent literature about possible interactions between malaria, helminthiases, and the gut microbiota. The knowledge from this exercise will inform innovation possibilities for future tools, technologies, approaches, and policies around the prevention and management of malaria in endemic countries.
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@#Soil-transmitted helminth (STH) infections, mainly caused by Ascaris lumbricoides, Trichuris trichiura, and hookworms, are among the most common intestinal parasites that infect humans. The infections are widely distributed throughout tropical and subtropical countries, including Malaysia, particularly in underprivileged communities. Microscopic and culture techniques have been used as a gold standard for diagnostic techniques. However, these methods yield low sensitivity and specificity, laborious and time-consuming. Therefore, simple, rapid, and accurate alternative methods are needed for the simultaneous detection of STH infections. Although advanced technologies such as real-time multiplex PCR have been established, the use of this technique as a routine diagnostic is limited due to the high cost of the instrument. Therefore, a single-round multiplex conventional PCR assay for rapid detection of four STH species in the fecal sample was developed in this study. To perform the single-round multiplex PCR, each pair of species-specific primers was selected from target genes, including Ancylostoma duodenale (Internal Transcribed Spacer 2; accession No. AJ001594; 156 base pair), Necator americanus (ITS 2; accession No. AJ001599; 225 base pair), Ascaris lumbricoides (Internal Transcribed Spacer 1; accession No. AJ000895; 334 base pair) and Trichuris triciura (partial ITS 1, 5.8s rRNA and partial ITS 2; accession No. AM992981; 518 base pair). The results showed that the newly designed primers could detect the DNA of STH at low concentrations (0.001 ng/μl) with no cross-amplification with other species. This assay enables the differentiation of single infections as well as mixed infections. It could be used as an alternative and is a convenient method for the detection of STHs, especially for the differentiation of N. americanus and A. duodenale.
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INTRODUCTION: Different interventions have been done to reduce the burden of soil-transmitted helminths (STH). The available evidences in Ethiopia in either school or community-based school-aged children (SAC) have limitation in wetland areas. This study assessed the prevalence and associated factors of STH infection among SAC in wetland and non-wetland areas of Blue Nile Basins, Amhara Region, Northwest Ethiopia. METHOD: A community-based comparative study was conducted from October to November, 2019. Multistage stratified random sampling technique used to select 716 SAC. Data were collected using structured questionnaire and observational checklist. Stool samples were collected from children using tight-fitting plastic cups following the standard procedures. Data were coded and entered into Epi data version 4.6 and exported to SPSS version 20 software. Bivariate and multivariable logistic regression analysis was employed to identify factors associated with STH. RESULTS: The overall prevalence of STH was 30.30% (95% CI: 26.90, 33.90) and did not show significant variation between wetland (33.60% (95% CI: 28.80, 39.60%)) and non-wetland (27.0% (95% CI: (21.90, 31.60)) areas. Presence of human feces near the house and certain habits such as nail trimming and playing with mud/soil was not different between wetland and non-wetlands. Nonetheless, the presence of human feces near the house of respondents was found to be significantly associated with STH infection (p value < 0.001). Moreover, other factors significantly associated with STH infection were lack of nail trimming (p value < 0.001) and playing with mud/soil (p value < 0.01). CONCLUSIONS: The prevalence of STH was high and did not show significant variation between the two areas. Emphasis needs to be given for hygiene and lifestyle-related factors.
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Soil-transmitted helminths (STH) affect hundreds of millions worldwide and are some of the most important neglected tropical diseases in terms of morbidity. Due to the difficulty in studying STH human infections, rodent models have become increasingly used, mainly because of their similarities in life cycle. Ascaris suum and Trichuris muris have been proven appropriate and low maintenance models for the study of ascariasis and trichuriasis. In the case of hookworms, despite most of the murine models do not fully reproduce the life cycle of Necator americanus, their proteomic similarity makes them highly suitable for the development of novel vaccine candidates and for the study of hookworm biological features. Furthermore, these models have been helpful in elucidating some basic aspects of our immune system, and are currently being used by numerous researchers to develop novel molecules with immunomodulatory proteins. Herein we review the similarities in the proteomic composition between Nippostrongylus brasiliensis, Heligmosomoides polygyrus bakeri and Trichuris muris and their respective human counterpart with a focus on the vaccine candidates and immunomodulatory proteins being currently studied.
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Helmintos , Tricuriasis , Animales , Ascaris lumbricoides , Ratones , Prevalencia , Proteómica , Roedores , SueloRESUMEN
BACKGROUND: Soil-transmitted helminths (STHs), such as hookworm, roundworm and whipworm, and food-borne trematodiases, including Clonorchis sinensis, remain a public health problem worldwide, especially in tropical and subtropical regions. OBJECTIVE: We aimed to determine the current prevalence of these parasites in Guangxi, China, which is located in a subtropical region. METHODS: A cross-sectional study and a 4-year longitudinal surveillance study were carried out. Stool samples were collected and examined microscopically for parasite eggs using the modified Kato-Katz thick smear method. RESULTS: The study subjects selected using stratified random cluster sampling for the cross-sectional study and longitudinal surveillance study numbered 15,683 and 24,429, respectively. In the cross-sectional study, hookworm, roundworm, whipworm, pinworm, C. sinensis, and tapeworm were found. The total prevalence of soil-transmitted helminths (STHs) was 6.4% (95% CI, 6.0-6.8). The prevalences of C. sinensis, hookworm, roundworm, whipworm, and pinworm were 10.6%, 4.2%, 0.3%, 0.3%, and 1.8%, respectively. The prevalence of C. sinensis in males (14.0%, 95% CI, 13.3-14.8) was significantly higher than in females (7.2%, 95% CI, 6.7-7.8) (P = 0.0001). The prevalence also was significantly higher in the medical worker group (20.8%, 95% CI, 12.9-28.7) than in all other occupational groups (10.5%, 95% CI, 10.0-11.0) (P = 0.0001). The prevalence of hookworm in females (5.3%, 95% CI, 4.8-5.8) was significantly higher than in males (3.0%, 95% CI, 2.6-3.3) (P = 0.0001). In the longitudinal surveillance study, the prevalence of C. sinensis and STHs in 2016, 2017, 2018, and 2019 were 12.0%, 6.0%, 11.0%, and 10.0% and 2.6%, 2.8%, 1.5%, and 1.5%, respectively. CONCLUSIONS: Adult male and occupation of and medical workers are risk factors for infection with C. sinensis and hookworm. The prevalence rate of C. sinensis remains high while those of the other STHs are decreasing, suggesting that enhanced health education should be focused on C. sinensis in Guangxi.
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Strongyloides stercoralis is a neglected soil-transmitted helminth affects approximately 100-370 million people globally. The life cycle is unusual as only larvae can be found in stool specimens. Thecurrent review and meta-analysis represented the distribution of strongyloidiasis in general population of the world based on published papers. Five English databases (Science Direct, Scopus, PubMed, Web of Science, and Google Scholar(were explored for literature published before October 2019.Altogether 235 studies (862243 participants) was eligible. Regarding diagnostic method, the overall prevalence for studies performed microscopic, culture, immunological and molecular method was 1.47% (95% CI = 1.56%), 10.08% (95% CI = 8.99% - 11.16%), 23.88% (95% CI = 20.82% - 26.94%) and 9.3% (95% CI = 7.2% - 11.3%), respectively. Based on microscopic methods, the highest prevalence was related to the Western Pacific region [9.47% (95% CI = 8.55% - 10.39%)]. According to the culture method, Western Pacific region [21.36% (95% CI = 16.32% - 26.39%)] had the highest estimated pooled prevalence. In immunological studies, Eastern Mediterranean Region [40.72% (95% CI = 36.74% - 44.70%)] had the highest seroprevalence.Also in molecular surveys, the highest prevalence was related to the African region [19.72% (95% CI = 16.71% - 22.73%)]. The current study indicated that strongyloidiasis is still considered a health problem in many parts of the world. Thus a comprehensive control program and improvement of public health sectors are required.
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Strongyloides stercoralis , Estrongiloidiasis , Animales , Heces , Salud Global , Humanos , Prevalencia , Estudios Seroepidemiológicos , Estrongiloidiasis/epidemiologíaRESUMEN
BACKGROUND: Pregnancy is a key step for human's reproduction and continuity of generation. Pregnant women are among at risk groups for the infection of soil-transmitted helminths (STHs). STHs are highly prevalent in low- and middle-income countries due to the deprived environmental sanitation and personal hygiene. Eating soil (geophagia) is also commonly practiced by pregnant women, particularly in developing countries. The aim of this study was to determine the prevalence of STHs and geophagia, and to assess associated factors among pregnant women in Jimma, Southwest Ethiopia. METHODS: A cross sectional study was conducted among 407 pregnant women attending antenatal care (ANC) at different health facilities located in Jimma Town. Data related to sociodemographic and geophagia practice was collected using a structured questionnaire and STH infections status was determined by using McMaster technique. RESULTS: A total of 407 pregnant women were included in this study. The overall prevalence of any STHs was 19.7% (80/407). Ascaris lumbricoides was the most prevalent 45(56.2%), followed by Trichuris trichiura 19(23.8%) and hookworms 12(15%). There were 4(5%) of double infection with A. lumbricoides and T. trichiura. Overall, 71 (17.4%) of the pregnant women responded to practice geophagia. STHs infection was significantly higher among geophagic pregnant women (p<0.01) and pregnant women who practiced geophagia were 3 times more likely (OR 2.9, 95% CI 1.3-4.2) to have the STHs compared to non-geophagic. Out of those who claimed soil eating habits, 59.1% preferred reddish soil type. Geophagia practice was significantly higher during the third trimester as compared to first and second (p<0.05). CONCLUSION: Geophagia is a risky behavior and this study showed a significant association of geophagia practice with STH infections, although the causal relation could not be established.
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Helmintiasis , Suelo , Animales , Estudios Transversales , Etiopía/epidemiología , Femenino , Helmintiasis/epidemiología , Humanos , Pica/epidemiología , Embarazo , Mujeres Embarazadas , Prevalencia , Suelo/parasitologíaRESUMEN
BACKGROUND: Strongyloidiasis is a parasitic disease that mainly affects humans and is caused by a roundworm called Strongyloides stercoralis. It is endemic in humid tropical regions that include Africa, Latin America and Southern Asia. Among the public health important soil-transmitted helminths (STHs) classified as neglected tropical diseases, S. stercoralis is the most neglected. A study of schistosomiasis and STHs mapping was conducted and S. stercoralis larvae were detected using the utilized diagnostic method; thus, this current study described the prevalence and risk factors of S. stercoralis infection in districts of Sabach Sanjal and Upper Badibou in The Gambia. METHODS: The cross-sectional study enrolled 851 schoolchildren, ages 7 to 14 years old. The participants were enrolled from 17 schools in Sabach Sanjal and Upper Badibou Districts. The WHO random sampling technique n/50 (25 boys and 25 girls) was used. Stool samples were collected from each participant and Kato-Katz smear method was used to screen for S. stercoralis infection. RESULTS: Out of the total 851 pupils, 76 pupils (8.9%) were positive for S. stercoralis infection. The mean age of infected persons was 10.1 years (±2.2). The prevalence of infection was higher among females (9.2%) than males (8.7%). Rates of infection for age categories 7-10 years and 11-14 years were 12.4% and 4.2%, respectively. Rates of infection by districts were 12.3% for Sabach Sanjal and 7.1% for Upper Badibou. Schoolchildren from Sabach Sanjal were 1.6 times more likely to have strongyloidiasis compared to those from Upper Badibou (aOR = 1.64, p-value = 0.058). Schoolchildren aged 7-10 years were 3.2 times more likely to have strongyloidiasis infection compared to the 11-14-year-olds (aOR = 3.20, p-value <0.001). Schoolchildren who 'sometimes' have water or tissue after defaecation have more infection rate compared to those who 'always' have water or tissue after defaecation. However, this difference was not statistically significant (aOR = 1.36, p-value = 0.308). CONCLUSION: The study revealed the prevalence of strongyloidiasis in Sabach Sanjal and Upper Badibou districts of The Gambia. Kato-Katz technique might be inadequate for detecting S. stercoralis; thus, more studies are needed to determine the true prevalence of the disease in these two districts through the combined use of highly sensitive techniques such as Baermann, Koga Agar Culture and polymerase chain reaction.
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Preventive chemotherapy (PC) is a WHO-recommended strategy to control and eliminate schistosomiasis and soil-transmitted helminths (STHs). We assessed the prevalence, intensity, and correlates of schistosomiasis and STH infection after five rounds of PC in southern Ethiopia. A total of 3162 school children from four schools in Wondo Gennet and Hawella Tula districts were screened for Schistosoma mansoni and STHs infection. The overall prevalence of S. mansoni infection was 25.8% (range between schools 11.6% to 54.1%), with light (19.1%), moderate (5.3%), and heavy (1.4%) infection intensities. A total of 61.6% S. mansoni-infected children were STH co-infected. The overall prevalence of STHs infection was 54.7% (range between schools 30.6-71.0%), with moderate-to-heavy intensity infections being 16.3%. Ascaris lumbricoides was the most prevalent 45% (95% CI, 43.5-47) followed by Trichuris trichiura 25.3% (95% CI, 23.8-26.9) and hookworm 6.1% (95% CI, 5.3-7). A total of 33.7% of STHs-infected children had A. lumbricoides and T. trichiura co-infections. S. mansoni infection was significantly associated with school and STHs co-infection (p < 0.001). STH infection was correlated with school and younger age (p < 0.001). Despite repeated PC, S. mansoni and STH infection remain significant health problems, and the WHO target to control schistosomiasis and eliminate STH by 2020 may not be achieved. Intensified control and prevention measures, including drug efficacy surveillance, is recommended.
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INTRODUCTION: In Bangladesh, the prevention and control strategy of soil-transmitted helminthiasis (STHs) is based on the mass drug administration (MDA) program. Despite bi-annual MDA since 2008, the reported compliance is still below the target, and the STH prevalence is high in several areas. This study was done to assess the feasibility and barriers of integrating health education (HE) intervention to achieve the target MDA compliance in the local context of Bangladesh. MATERIALS AND METHODS: A mixed-method study, utilizing PRISM (Practical Robust Implementation Sustainability Model) framework, was conducted between July 2017 to March 2018 in Dhaka and Sylhet divisions of Bangladesh. A total of 640 school-aged children selected from four different schools were divided into intervention and control groups. Eight focus group discussions (FGDs) and eight in-depth interviews (IDIs) were also conducted among 56 adults, including parents of school-aged children, school teachers, and health officers. RESULTS: Quantitative findings revealed that HE intervention had a significant role (P < .05) to improve the mean knowledge score in the intervention group (3.35) compared to the control group (0.29). STH preventive behaviours and MDA participating attitudes were also significantly increased in the intervention group (P < .05) compared to the control group. Some of the major barriers associated with HE integration identified in the qualitative study were budget deficiencies, inadequate training of program implementers, and information gaps. In contrast, the school environment and positive community attitudes were observed as supportive factors for the integration of HE. CONCLUSION: Increased knowledge score and behaviour changes due to HE intervention demonstrated in this study hint that integration of HE with MDA is feasible and can be promising to promote MDA compliance and to reduce STH prevalence in this setting. However, the allocation of adequate budget, as well as coordination and collaboration with local political context, should be addressed for the sustainability of integration.
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Current efforts for the prevention of malaria have resulted in notable reductions in the global malaria burden; however, they are not enough. Good hygiene is universally considered one of the most efficacious and straightforward measures to prevent disease transmission. This work analyzed whether improved drinking water and sanitation (WS) conditions were associated with a decreased risk of malaria infection. Data were acquired through surveys published between 2006 and 2018 from the Demographic and Health Program in sub-Saharan Africa (SSA). Multiple logistic regression was used for each national survey to identify the associations between WS conditions and malaria infection diagnosed by microscopy or a malaria rapid diagnostic test (RDT) among children (0-59â¯months), with adjustments for age, gender, indoor residual spraying (IRS), insecticide-treated net (ITN) use, house quality, and the mother's highest educational level. Individual nationally representative survey odds ratios (ORs) were combined to obtain a summary OR using a random-effects meta-analysis. Among the 247,440 included children, 18.8% and 24.2% were positive for malaria infection based on microscopy and RDT results, respectively. Across all surveys, both unprotected water and no facility users were associated with increased malaria risks (unprotected water: aOR 1.17, 95% CI 1.07-1.27, Pâ¯=â¯0.001; no facilities: aOR 1.35, 95% CI 1.24-1.47, Pâ¯<â¯0.001; respectively), according to microscopy, whereas the odds of malaria infection were 48% and 49% less among piped water and flush-toilet users, respectively (piped water: aOR 0.52, 95% CI 0.45-0.59, Pâ¯<â¯0.001; flush toilets: aOR 0.51, 95% CI 0.43-0.61, Pâ¯<â¯0.001). The trends of individuals diagnosed by RDT were consistent with those of individuals diagnosed by microscopy. Risk associations were more pronounced among children with a "nonpoor" socioeconomic status who were unprotected water or no facility users. WS conditions are a vital risk factor for malarial infection among children (0-59â¯months) across SSA. Improved WS conditions should be considered a potential intervention for the prevention of malaria in the long term.
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Soil-transmitted helminths (STHs) are the most common intestinal parasites infecting humans worldwide. STH infections are a major cause of morbidity and disability. Accurate diagnostic tools are pivotal for assessing the exact prevalence of parasitic infections. Microscopic examination and culture techniques have been used to observe the presence of eggs or larvae of parasites in stool samples, but they are time-consuming and have low sensitivity. Therefore, accurate, simple, and inexpensive diagnostic techniques are still required for simultaneous detection of STH infections. Although molecular-based techniques, such as real-time PCR and multiplex real-time PCR, have been developed, they are not suitable for routine diagnosis due to the requirement for expensive reagents and instruments. In this study, we established a conventional multiplex PCR for simultaneous rapid detection of Ascaris lumbricoides, Necator americanus, and Strongyloides stercoralis in stool samples. Our results show that the multiplex PCR could detect the DNA of STHs at a very low target gene concentrations (lower than 1 pg) with no cross-amplification. Multiplex PCR had five times higher sensitivity than the formalin-ethyl acetate concentration technique (FECT) in the detection of multiple infections, and two times higher for detection of S. stercoralis. However, multiplex PCR was comparable to FECT in the detection of A. lumbricoides and N. americanus. In conclusion, this method could be used as an alternative method for the detection of STHs, especially for S. stercoralis.
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BACKGROUND AND AIM: School-based preventive mass chemotherapy has been a key component of Ethiopia's national plan for the control of soil-transmitted helminths. Without an impact evaluation on the impact of a deworming program on infection levels, it is unclear whether the deworming program warrants levels of environmental transmission of infection. This study aimed to determine the impact of annual preventive mass chemotherapy for soil-transmitted helminths among schoolchildren in an endemic area of Gurage zone, south-central Ethiopia. METHODS: A repeated school-based quantitative prospective cross-sectional method was employed. Data were collected from study participants selected using systematic sampling with probability proportional to size at baseline and after annual treatment. Fresh stool samples were collected and processed using the KatoâKatz technique at the Wolkite University parasitology laboratory. SPSS-21 was used for data management and analysis. Changes in parasitological variables after treatment were estimated. RESULTS: Overall, 41.1% prevalence and 22.3% mean geometric infection-intensity reduction were found. Reductions in prevalence of Schistosoma mansoni and hookworms were 13.2% and 15.3%, respectively. Similarly, decreases in prevalence were seen in Ascaris lumbricoides and Trichuris trichiura, representing 94.4% and 80.0% reduction rates, respectively, while 25.9% of the children had heavy S. mansoni (≥400 eggs per gram) infections at baseline, which were reduced to 4.5% after annual treatment. Geometric mean infection intensity-reduction rates for hookworms, A. lumbricoides, and T. trichiura were 80.8%, 20.2%, and 96.7%, respectively. CONCLUSION: Annual mass chemotherapy failed to clear soil-transmitted helminths completely in the present study. However, it resulted in a substantial reduction in overall prevalence and infection intensity. Therefore, other than deworming for school children, interventions such as access to improved personal hygiene and environmental hygiene in school should be emphasized to interrupt transmission.
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BACKGROUND: Necator americanus (hookworm) and Plasmodium falciparum co-infections are common in endemic communities in rural Ghana. Human immune responses to P. falciparum and hookworm are complex, and the dynamics of cytokine levels and effector mediators are poorly understood. This study aimed to determine the effect of hookworm and P. falciparum co-infection on parasite intensities and cytokine profiles in individuals before and after deworming drug treatment. METHODS: In this cross-sectional study conducted in the Kintampo North Municipality of Ghana blood and stool samples were analyzed from 984 participants (aged 4-88â¯years). Stool samples were collected at baseline from all participants and examined for the presence of hookworm using the Kato-Katz method. Blood and stool samples were analysed again two weeks after albendazole treatment of hookworm infected individuals. Malaria parasitaemia was estimated by light microscopy and P. falciparum-specific 18S rRNA gene PCR method used for species identification. Serum levels of circulating cytokines interleukins -5, -10 (IL-5, IL-10), tumor necrosis factor [TNF]-α, and eotaxin [CCL11] were determined using ELISA based methods. RESULTS: Malaria parasitaemia was significantly reduced in hookworm and P. falciparum co-infected individuals (pâ¯=â¯0.0018) while hookworm intensity was similar between groups. IL-10 level was significantly higher in the co-infected individuals (39.9⯱â¯12.2â¯pg/ml) compared to the single infected or the uninfected group (10.7⯱â¯7.6â¯mg/ml). IL-5 level was higher in the hookworm only infected individual. TNF-α levels were higher in all infected groups compared to the uninfected controls. CCL11 levels were significantly higher in subjects infected with hookworm only or co-infected with hookworm and P. falciparum. There was a significantly negative correlation (rsâ¯=â¯-0.39, pâ¯=â¯0.021) between hookworm eggs per gram of stool and CCL11 levels in the group mono-infected with hookworm which was not affected by treatment. Treatment with albendazole led to a significant reduction of TNF-α (pâ¯=â¯0.041), IL-5 (pâ¯=â¯0.01) and IL-10 (pâ¯=â¯0.001) levels. CONCLUSION: This study shows that in the absence of other helminths, co-infection of hookworm with P. falciparum may modulate blood parasitemia levels and cytokine responses. Data also show that deworming drug treatment alters these cytokine profiles in hookworm infected subjects. Future studies to elucidate the potential mechanisms underlying these observations should include an assessment of parasite specific cellular responses.
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BACKGROUND: Plasmodium falciparum and soil transmitted helminth (STHs) infection are widespread in sub-Sahara Africa, where co-infection is also common. This study assessed the prevalence of these infections and their risk factors among pregnant women in Osogbo, Nigeria. METHODS: A total of 200 pregnant women attending the antenatal clinic were recruited. Plasmodium falciparum was detected using thick and thin film methods, while formol ether concentration method was used for STHs detection. A questionnaire was used to investigate the possible risk factors associated with acquisition of malaria and helminth infections. RESULTS: The prevalence of P. falciparum, STHs and their co-infection was 29.5%, 12% and 5% respectively. P. falciparum, STHs and P. falciparum + STHs co-infection was significantly higher in primigravidae (52.5% vs 58.3% vs 80%) than in secongravidae (18.6% vs 25.0% vs 20%) and multigravidae (28.8% vs 16.7% vs 0%) (p=0.02). Prevalence associated factors identified for P. falciparum was age (p=0.0001) while gravidity (p=0.02) was identified for P. falciparum + STHs co-infection. CONCLUSION: High prevalence of P. falciparum and helminth infections was observed among the pregnant women with primigravidae being the most susceptible to co-infection. There is an urgent need to implement an effective malaria and STHs preventive method for this high risk population.