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BACKGROUND: Onchocerciasis is endemic in most local government areas (LGAs) in Enugu and Ogun states. Most meso- and hyper-endemic LGAs have received many rounds of ivermectin mass drug administration (MDA). This study aimed to determine the current prevalence of onchocerciasis in villages in Enugu and Ogun states that were formerly highly endemic and to assess progress toward elimination of the infection in areas believed to be at high risk for persistence. METHODS: Cross-sectional community surveys were conducted 8 to 12 months after the last round of MDA in 16 villages (6 in Enugu state and 10 in Ogun state) in individuals aged ≥ 18 years. Study participants were examined for the presence of palpable subcutaneous nodules. Skin snips from the posterior iliac crests were used to assess microfiladermia (Mf) prevalence and density. RESULTS: 643 subjects were palpated for nodules and 627 individuals (225 in Enugu state; 402 in Ogun state) provided skin snips. Nodule prevalence in the study villages ranged from 42 to 66.7% in Enugu state and from 0 to 25.0% in Ogun state. Mf prevalence in the Enugu and Ogun study villages ranged from 32 to 51.1% and 0 to 28.6%, respectively. Geometric mean skin Mf density in surveyed Enugu state villages ranged between 1 and 3.1 Mf/mg; these values were < 1 Mf/mg in all but one community in Ogun state villages. CONCLUSION: Results from this study show that onchocerciasis persists in adults in many villages in Enugu and Ogun states despite many prior rounds of ivermectin MDA. Prevalence was higher in villages surveyed in Enugu than in Ogun. Low Mf densities suggest the MDA program is working well to reduce disease, but more time will be required to reach the elimination goal.
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Oncocercosis , Adulto , Humanos , Oncocercosis/tratamiento farmacológico , Oncocercosis/epidemiología , Ivermectina/uso terapéutico , Estudios Transversales , Nigeria/epidemiología , Administración Masiva de Medicamentos , PrevalenciaRESUMEN
Objective: This study assessed the coverage of albendazole (ALB) in mass drug administration (MDA) programs implemented before (2019) and during the (2020 and 2021) COVID-19 pandemic in Ekiti State, Nigeria. Methods: Standardized questionnaires were administered to 1,127 children across three peri-urban communities to ascertain if they received and swallowed ALB across the years. Reasons, why ALB was not received, were documented and analyzed in SPSS. 20.0. Results: In 2019, the medicine reach was between 42.2%-57.8%, however, during the pandemic, the reach significantly reduced to 12.3%-18.6%, and increased to 28.5%-35.2% in 2021 (p < 0.000). About 19.6%-27.2% of the participants have missed 1 MDA, while 26.9%-37.8% and 22.4%-32.8% have missed 2 and 3 MDAs, respectively. The majority who did not receive ALB (60.8%-75%) claimed drug distributors never came, while about 14.9%-20.3% mentioned they did not hear about MDA. However, individual compliance towards swallowing was above 94% across the study years (p < 0.00). Conclusion: These results highlight the need to explore the perceptions of those who have consistently missed MDAs, and also understand the health-system-related issues including those imposed by the pandemic affecting MDA.
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COVID-19 , Helmintiasis , Niño , Humanos , Albendazol/uso terapéutico , Helmintiasis/tratamiento farmacológico , Helmintiasis/epidemiología , Administración Masiva de Medicamentos/métodos , Pandemias , Nigeria/epidemiología , Control de Enfermedades TransmisiblesRESUMEN
BACKGROUND: Girls and women living in endemic areas for urogenital schistosomiasis may have lifelong vulnerability to female genital schistosomiasis (FGS). For >2 decades, the importance of FGS has been increasing in sub-Saharan Africa, but without established policies for case detection and treatment. This research aimed to understand the level of FGS knowledge of frontline health workers and health professionals working in endemic areas and to identify health system needs for the effective management of FGS cases and prevention of further complications due to ongoing infections. METHODS: Workshops were conducted with health workers and stakeholders using participatory methods. These workshops were part of a quality improvement approach to develop the intervention. RESULTS: Health workers' and system stakeholders' knowledge regarding FGS was low. Participants identified key steps to be taken to improve the diagnosis and treatment of FGS in schistosomiasis-endemic settings, which focused mainly on awareness creation, supply of praziquantel, development of FGS syndromic management and mass administration of praziquantel to all eligible ages. The FGS intervention component varies across countries and depends on the health system structure, existing facilities, services provided and the cadre of personnel available. CONCLUSION: Our study found that co-developing a new service for FGS that responds to contextual variations is feasible, promotes ownership and embeds learning across health sectors, including healthcare providers, NTD policymakers and implementers, health professionals and community health workers.
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Praziquantel , Esquistosomiasis Urinaria , Femenino , Humanos , Nigeria , Liberia , Mejoramiento de la Calidad , Esquistosomiasis Urinaria/diagnóstico , Esquistosomiasis Urinaria/tratamiento farmacológico , Esquistosomiasis Urinaria/epidemiología , Genitales Femeninos , Atención Primaria de SaludRESUMEN
BACKGROUND: Detection and management of female genital schistosomiasis (FGS) within primary healthcare is crucial for achieving schistosomiasis elimination, however, current technical strategies are not feasible in many settings. In Nigeria, there are currently no established standard operating procedures to support front-line health workers. This article presents an evaluation of piloting an FGS care package in two LGAs of Ogun State, Nigeria. METHODS: We used quantitative and qualitative analysis, including 46 interviews with patients, health workers and the quality improvement team; observations of training, learning sessions and supervision across 23 heath facilities; and records of patients detected and managed. RESULTS: Of 79 women and girls who were screened, 66 were treated and followed up. Health workers assimilated knowledge of FGS and effectively diagnosed and managed patients, demonstrating the feasibility of using symptomatic screening and treatment tools to diagnose and care for women or girls with suspected FGS. Challenges included establishing a referral pathway to tertiary care for patients with complications, insecurity, gender norms that limited uptake and sensitization, the limited capacity of the workforce, conflicting priorities and praziquantel acquisition. CONCLUSIONS: Simple tools can be used in primary healthcare settings to detect and manage women and girls with FGS. Contextual challenges must be addressed. Sustainability will require political and financial commitments.
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Esquistosomiasis , Humanos , Femenino , Nigeria , Proyectos Piloto , Esquistosomiasis/prevención & control , Genitales Femeninos , Atención Primaria de SaludRESUMEN
Until recently, the epidemiology and control of schistosomiasis in sub-Saharan Africa have focused primarily on infections in school-aged children and to a lesser extent on adults. Now there is growing evidence and reports of infection in infants and pre-school-aged children (≤ 6 years old) in Ghana, Kenya, Mali, Niger, Nigeria and Uganda, with reported prevalence from 14% to 86%. In this review, we provide available information on the epidemiology, transmission and control of schistosomiasis in this age group, generally not considered or included in national schistosomiasis control programmes that are being implemented in several sub-Saharan African countries. Contrary to previous assumptions, we show that schistosomiasis infection starts from early childhood in many endemic communities and factors associated with exposure of infants and pre-school-aged children to infection are yet to be determined. The development of morbidity early in childhood may contribute to long-term clinical impact and severity of schistosomiasis before they receive treatment. Consistently, these issues are overlooked in most schistosomiasis control programmes. It is, therefore, necessary to review current policy of schistosomiasis control programmes in sub-Saharan Africa to consider the treatment of infant and pre-school-aged children and the health education to mothers.
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Control de Infecciones/métodos , Esquistosomiasis/epidemiología , Esquistosomiasis/prevención & control , Adulto , África del Sur del Sahara/epidemiología , Animales , Antihelmínticos/uso terapéutico , Niño , Preescolar , Femenino , Educación en Salud , Humanos , Lactante , Masculino , Praziquantel/uso terapéutico , Esquistosomiasis/tratamiento farmacológico , Esquistosomiasis/transmisiónRESUMEN
BACKGROUND: Over the past 20 years, schistosomiasis control has been scaled up. Preventive chemotherapy with praziquantel is the main intervention. We aimed to assess the effect of preventive chemotherapy on schistosomiasis prevalence in sub-Saharan Africa, comparing 2000-10 with 2011-14 and 2015-19. METHODS: In this spatiotemporal modelling study, we analysed survey data from school-aged children (aged 5-14 years) in 44 countries across sub-Saharan Africa. The data were extracted from the Global Neglected Tropical Diseases database and augmented by 2018 and 2019 survey data obtained from disease control programmes. Bayesian geostatistical models were fitted to Schistosoma haematobium and Schistosoma mansoni survey data. The models included data on climatic predictors obtained from satellites and other open-source environmental databases and socioeconomic predictors obtained from various household surveys. Temporal changes in Schistosoma species prevalence were estimated by a categorical variable with values corresponding to the three time periods (2000-10, 2011-14, and 2015-19) during which preventive chemotherapy interventions were scaled up. FINDINGS: We identified 781 references with relevant geolocated schistosomiasis survey data for 2000-19. There were 19 166 unique survey locations for S haematobium and 23 861 for S mansoni, of which 77% (14 757 locations for S haematobium and 18 372 locations for S mansoni) corresponded to 2011-19. Schistosomiasis prevalence among school-aged children in sub-Saharan Africa decreased from 23·0% (95% Bayesian credible interval 22·1-24·1) in 2000-10 to 9·6% (9·1-10·2) in 2015-19, an overall reduction of 58·3%. The reduction of S haematobium was 67·9% (64·6-71·1) and that of S mansoni 53·6% (45·2-58·3) when comparing 2000-10 with 2015-19. INTERPRETATION: Our model-based estimates suggest that schistosomiasis prevalence in sub-Saharan Africa has decreased considerably, most likely explained by the scale-up of preventive chemotherapy. There is a need to consolidate gains in the control of schistosomiasis by means of preventive chemotherapy, coupled with other interventions to interrupt disease transmission. FUNDING: European Research Council and WHO.
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Antihelmínticos/uso terapéutico , Praziquantel/uso terapéutico , Schistosoma haematobium/efectos de los fármacos , Schistosoma mansoni/efectos de los fármacos , Esquistosomiasis/tratamiento farmacológico , Análisis Espacio-Temporal , Adolescente , África del Sur del Sahara/epidemiología , Animales , Quimioprevención , Niño , Preescolar , Estudios Transversales , Bases de Datos Factuales , Humanos , Praziquantel/administración & dosificación , Prevalencia , Esquistosomiasis/clasificación , Esquistosomiasis/epidemiología , Instituciones AcadémicasRESUMEN
BACKGROUND: The need to control Neglected Tropical Diseases (NTDs) and sustain progress towards elimination through mass administration of medicines requires substantial communal participation. This study, therefore, assessed the knowledge and perception of attendees' regarding NTDs and its control activities during the inaugural World NTD day event in Ekiti State, Nigeria. METHODOLOGY: A cross-sectional study involving the administration of pretested semi-structured questionnaires to consenting attendees at the Inaugural World NTD day event was conducted on the 30th January, 2020. The questionnaire collected data on attendee's demography, knowledge and awareness about NTDs and its control in Nigeria. Quantitative data were analysed using descriptive statistics in SPSS. 20.0 software and expressed as frequencies and percentages. However, qualitative data to support quantitative analysis were obtained using open-ended questionnaires and analysed thematically. PRINCIPAL FINDINGS/CONCLUSION: A total of 309 attendees comprising 167 (54.0%) females, and 142 (46.0%) males participated in this study. By age groupings, majority 206 (66.7%) were within 15-25 years. 167 (54.8%) of the attendees have not heard about NTDs before, whereas 77(35.0%) have heard about NTDs through the advertisement of the event. 181(63.3%) were aware of ongoing NTD control programs in schools and communities. Also, 246 (83.4%) of them have not taken or do not know anyone that has taken drugs donated in schools or communities. The number of attendees 41(13.3%) who incorrectly classified malaria as NTDs is higher than those who recognized onchocerciasis 36 (11.7%) and worm infections 34(11.0%) as NTDs (p>0.05). This study has shown that awareness and knowledge about NTDs control activities in Ekiti State is low, thus justifying the event as an awareness day for addressing NTDs. Public enlightment and regular promotional activities such as media engagement will raise the public appreciation and participation in NTDs control activities.
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Conocimientos, Actitudes y Práctica en Salud , Enfermedades Desatendidas/diagnóstico , Enfermedades Desatendidas/prevención & control , Prevención Primaria/métodos , Adolescente , Adulto , Quimioprevención/métodos , Estudios Transversales , Femenino , Humanos , Masculino , Nigeria , Encuestas y Cuestionarios , Medicina Tropical/educación , Adulto JovenRESUMEN
In most endemic sub-Saharan African countries, repeated infections with soil-transmitted helminth (STH) occur as early as six weeks after the end of mass drug administration (MDA) with albendazole. In this study, we designed a new health educational board game Worms and Ladders and evaluated its potential to complement MDA with albendazole and reduce reinfection rates through the promotion of good hygiene practices among school-aged children. The evaluation employed a randomized control trial (RCT) design. Baseline knowledge, attitude and practices (KAP) relating to STH were obtained using a questionnaire from 372 pupils across six schools in Abeokuta, Nigeria. Schools were randomly assigned into intervention and control group, with the former and latter receiving Worms and Ladders and the common Snake and Ladder board game respectively. Fresh stool samples were also collected at baseline for STH diagnosis before administering 400mg single dose albendazole. Follow-up assessments of STH burden and KAP were conducted three and six months' post-intervention. Data generated from the study were analyzed using SPSS 20.0 software, with confidence interval set at 95%. Prevalence of STH dropped from 25.0% to 10.4% in the intervention group and 49.4% to 33.3% in the control group at three months' post-intervention. The prevalence further dropped to 5.6% in the intervention group at six months' post-intervention. However, it increased to 37.2% in the control group at six months' post-intervention. There was a significant difference (p<0.05) in prevalence after intervention among the groups. KAP on transmission, control and prevention of STH significantly improved (p<0.05) from 5.2% to 97.9% in the intervention group compared to 6.2% to 7.1% in the control group. The Worms and Ladders board game shows the potential to teach and promote good hygiene behavior among SAC. These findings posit the newly developed game as a reliable tool to complement mass drug administration campaigns for STH control.
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Juegos Recreacionales , Educación en Salud/métodos , Helmintiasis/prevención & control , Adolescente , Albendazol/uso terapéutico , Antihelmínticos/uso terapéutico , Niño , Preescolar , Heces/parasitología , Femenino , Helmintiasis/tratamiento farmacológico , Humanos , Masculino , Administración Masiva de Medicamentos , Nigeria/epidemiología , Prevalencia , Instituciones AcadémicasRESUMEN
Schistosoma japonicum, differs from the African species including S. mansoni and S. haematobium, is a zoonotic parasite as it infects both human and animals including domestic ruminant animals such as cattle and animals from the wild. Considering China's success story in the elimination of schistosomiasis, the China-Africa collaboration on schistosomaisis elimination in Africa is an important cooperative health development initiative. This review examines the importance of China-Africa collaboration on schistosomiasis elimination using effective surveillance-response intervention strategy as the platform to effectively drive the elimination of schistosomiasis in Africa. Three conclusions were made after reviewing the similarity and differences in schistososmiasis control programmes between China and African continent as follows: (i) Politically, China's lessons is that leveraging on the integrated control strategies and the recognition that schistosomiasis is a public health problem which prompted the interest of government in China. It is necessary for African leaders and governments to recognize schistosomiasis as a public health challenge that must be given serious attention in terms of funding and setting up frameworks to complement control efforts. (ii) Technically, efficient monitoring and surveillance system mechanism will facilitate contextual and effective management of schistosomiasis elimination across different environment, and African programme managers should embrace the use of appropriate diagnostic tools to guide treatment strategies at different thresholds of schistosomiasis control. (iii) Strategically, effective control of snail intermediate hosts and precision mapping of snail distribution should be prioritized for successful schistosomiasis elimination in Africa.
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BACKGROUND: The control of urinary schistosomiasis in Ogun State, Nigeria remains inert due to lack of reliable data on the geographical distribution of the disease and the population at risk. To help in developing a control programme, delineating areas of risk, geographical information system and remotely sensed environmental images were used to developed predictive risk maps of the probability of occurrence of the disease and quantify the risk for infection in Ogun State, Nigeria. METHODS: Infection data used were derived from carefully validated morbidity questionnaires among primary school children in 2001-2002, in which school children were asked among other questions if they have experienced "blood in urine" or urinary schistosomiasis. The infection data from 1,092 schools together with remotely sensed environmental data such as rainfall, vegetation, temperature, soil-types, altitude and land cover were analysis using binary logistic regression models to identify environmental features that influence the spatial distribution of the disease. The final regression equations were then used in Arc View 3.2a GIS software to generate predictive risk maps of the distribution of the disease and population at risk in the state. RESULTS: Logistic regression analysis shows that the only significant environmental variable in predicting the presence and absence of urinary schistosomiasis in any area of the State was Land Surface Temperature (LST) (B = 0.308, p = 0.013). While LST (B = -0.478, p = 0.035), rainfall (B = -0.006, p = 0.0005), ferric luvisols (B = 0.539, p = 0.274), dystric nitosols (B = 0.133, p = 0.769) and pellic vertisols (B = 1.386, p = 0.008) soils types were the final variables in the model for predicting the probability of an area having an infection prevalence equivalent to or more than 50%. The two predictive risk maps suggest that urinary schistosomiasis is widely distributed and occurring in all the Local Government Areas (LGAs) in State. The high-risk areas (>/= 50% prevalence) however, are confined to scatter foci in the north western part of the State. The model also estimated that 98.99% of schools aged children (5-14 years) are living in areas suitable for urinary schistosomiasis transmission and are at risk of infection. CONCLUSION: The risk maps developed will hopefully be useful to the state health officials, by providing them with detailed distribution of urinary schistosomiasis, help to delineate areas for intervention, assesses population at risk thereby helping in optimizing scarce resources.
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Sistemas de Información Geográfica , Esquistosomiasis Urinaria/epidemiología , Adolescente , Animales , Niño , Preescolar , Vectores de Enfermedades , Ambiente , Humanos , Modelos Logísticos , Nigeria/epidemiología , Prevalencia , Medición de Riesgo , Schistosoma haematobium/patogenicidad , Esquistosomiasis Urinaria/parasitología , Encuestas y CuestionariosRESUMEN
This paper reports the results of a cross-sectional study on the growth of Fulani children, aged 6 months-15 years, living in Kwara, Ogun and Oyo States, South western Nigeria. This population of Fulani are fully settled pastoralists whose economy and culture are now centred on cattle and farming. There is a dearth of information on the prevalence of malnutrition in this group. We measured the heights and weights of 164 girls and 167 boys and determined their anthropometric indices, height-for-age (HA), weight-for-height (WH), and weight-for-age (WA) Z-scores. The prevalence of stunting (HAZ < -2), wasting (WHZ < -2) and underweight (WAZ < - 2) was 38.7 % , 13.6 % , and 38.7 % , respectively, when compared to the reference NC HS WHO standard used for defining stunting, wasting and underweight. Boys were more malnourished than girls, but this was not statistically significant (stunting: chi(2)=0.36; df=1; p=0.54); (underweight: chi(2)=1.10; df=1; p=0.29); and (wasting: chi(2)=0.00; df=1; p=0.98) The mean of Z- scores of height-for-age, weight-for-age and weight-for-height in the study population were -1.502, -1.634 and - 0.931, respectively. The SD was 1.52, 1.09 and 1.20, respectively. Using WHO Malnutrition Classification systems, 38.7 % of the children were found to be malnourished. It was concluded that malnutrition among children in this population could be linked to changing food habits and lifestyle from nomadic to sedentary living.
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Trastornos de la Nutrición del Niño/diagnóstico , Trastornos de la Nutrición del Niño/epidemiología , Estilo de Vida , Salud Pública , Salud Rural , Adolescente , Niño , Preescolar , Estudios Transversales , Femenino , Trastornos del Crecimiento/diagnóstico , Trastornos del Crecimiento/epidemiología , Humanos , Lactante , Masculino , Nigeria/epidemiología , Estado Nutricional , Prevalencia , Población RuralRESUMEN
BACKGROUND: Schistosomiasis affects more than 200 million individuals, mostly in sub-Saharan Africa, but empirical estimates of the disease burden in this region are unavailable. We used geostatistical modelling to produce high-resolution risk estimates of infection with Schistosoma spp and of the number of doses of praziquantel treatment needed to prevent morbidity at different administrative levels in 44 countries. METHODS: We did a systematic review to identify surveys including schistosomiasis prevalence data in sub-Saharan Africa via PubMed, ISI Web of Science, and African Journals Online, from inception to May 2, 2014, with no restriction of language, survey date, or study design. We used Bayesian geostatistical meta-analysis and rigorous variable selection to predict infection risk over a grid of 1â155â818 pixels at 5â×â5 km, on the basis of environmental and socioeconomic predictors and to calculate the number of doses of praziquantel needed for prevention of morbidity. FINDINGS: The literature search identified Schistosoma haematobium and Schistosoma mansoni surveys done in, respectively, 9318 and 9140 unique locations. Infection risk decreased from 2000 onwards, yet estimates suggest that 163 million (95% Bayesian credible interval [CrI] 155 million to 172 million; 18·5%, 17·6-19·5) of the sub-Saharan African population was infected in 2012. Mozambique had the highest prevalence of schistosomiasis in school-aged children (52·8%, 95% CrI 48·7-57·8). Low-risk countries (prevalence among school-aged children lower than 10%) included Burundi, Equatorial Guinea, Eritrea, and Rwanda. The numbers of doses of praziquantel needed per year were estimated to be 123 million (95% CrI 121 million to 125 million) for school-aged children and 247 million (239 million to 256 million) for the entire population. INTERPRETATION: Our results will inform policy makers about the number of treatments needed at different levels and will guide the spatial targeting of schistosomiasis control interventions. FUNDING: European Research Council, China Scholarship Council, UBS Optimus Foundation, and Swiss National Science Foundation.
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Esquistosomiasis/epidemiología , Adolescente , África del Sur del Sahara/epidemiología , Animales , Teorema de Bayes , Niño , Preescolar , Necesidades y Demandas de Servicios de Salud , Humanos , Morbilidad , Mozambique , Praziquantel/uso terapéutico , Prevalencia , Schistosoma haematobium/efectos de los fármacos , Schistosoma mansoni/efectos de los fármacos , Esquistosomiasis/tratamiento farmacológicoRESUMEN
BACKGROUND: The acceleration of the control of soil-transmitted helminth (STH) infections in Nigeria, emphasizing preventive chemotherapy, has become imperative in light of the global fight against neglected tropical diseases. Predictive risk maps are an important tool to guide and support control activities. METHODOLOGY: STH infection prevalence data were obtained from surveys carried out in 2011 using standard protocols. Data were geo-referenced and collated in a nationwide, geographic information system database. Bayesian geostatistical models with remotely sensed environmental covariates and variable selection procedures were utilized to predict the spatial distribution of STH infections in Nigeria. PRINCIPAL FINDINGS: We found that hookworm, Ascaris lumbricoides, and Trichuris trichiura infections are endemic in 482 (86.8%), 305 (55.0%), and 55 (9.9%) locations, respectively. Hookworm and A. lumbricoides infection co-exist in 16 states, while the three species are co-endemic in 12 states. Overall, STHs are endemic in 20 of the 36 states of Nigeria, including the Federal Capital Territory of Abuja. The observed prevalence at endemic locations ranged from 1.7% to 51.7% for hookworm, from 1.6% to 77.8% for A. lumbricoides, and from 1.0% to 25.5% for T. trichiura. Model-based predictions ranged from 0.7% to 51.0% for hookworm, from 0.1% to 82.6% for A. lumbricoides, and from 0.0% to 18.5% for T. trichiura. Our models suggest that day land surface temperature and dense vegetation are important predictors of the spatial distribution of STH infection in Nigeria. In 2011, a total of 5.7 million (13.8%) school-aged children were predicted to be infected with STHs in Nigeria. Mass treatment at the local government area level for annual or bi-annual treatment of the school-aged population in Nigeria in 2011, based on World Health Organization prevalence thresholds, were estimated at 10.2 million tablets. CONCLUSIONS/SIGNIFICANCE: The predictive risk maps and estimated deworming needs presented here will be helpful for escalating the control and spatial targeting of interventions against STH infections in Nigeria.
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Helmintiasis/tratamiento farmacológico , Helmintiasis/epidemiología , Helmintiasis/transmisión , Modelos Biológicos , Suelo/parasitología , Ancylostomatoidea/aislamiento & purificación , Animales , Antihelmínticos/uso terapéutico , Ascaris lumbricoides/aislamiento & purificación , Teorema de Bayes , Niño , Femenino , Sistemas de Información Geográfica , Geografía , Humanos , Masculino , Nigeria/epidemiología , Prevalencia , Factores de Riesgo , Trichuris/aislamiento & purificaciónRESUMEN
BACKGROUND: Interest is growing in predictive risk mapping for neglected tropical diseases (NTDs), particularly to scale up preventive chemotherapy, surveillance, and elimination efforts. Soil-transmitted helminths (hookworm, Ascaris lumbricoides, and Trichuris trichiura) are the most widespread NTDs, but broad geographical analyses are scarce. We aimed to predict the spatial and temporal distribution of soil-transmitted helminth infections, including the number of infected people and treatment needs, across sub-Saharan Africa. METHODS: We systematically searched PubMed, Web of Knowledge, and African Journal Online from inception to Dec 31, 2013, without language restrictions, to identify georeferenced surveys. We extracted data from household surveys on sources of drinking water, sanitation, and women's level of education. Bayesian geostatistical models were used to align the data in space and estimate risk of with hookworm, A lumbricoides, and T trichiura over a grid of roughly 1 million pixels at a spatial resolution of 5â×â5 km. We calculated anthelmintic treatment needs on the basis of WHO guidelines (treatment of all school-aged children once per year where prevalence in this population is 20-50% or twice per year if prevalence is greater than 50%). FINDINGS: We identified 459 relevant survey reports that referenced 6040 unique locations. We estimate that the prevalence of hookworm, A lumbricoides, and T trichiura among school-aged children from 2000 onwards was 16·5%, 6·6%, and 4·4%. These estimates are between 52% and 74% lower than those in surveys done before 2000, and have become similar to values for the entire communities. We estimated that 126 million doses of anthelmintic treatments are required per year. INTERPRETATION: Patterns of soil-transmitted helminth infection in sub-Saharan Africa have changed and the prevalence of infection has declined substantially in this millennium, probably due to socioeconomic development and large-scale deworming programmes. The global control strategy should be reassessed, with emphasis given also to adults to progress towards local elimination. FUNDING: Swiss National Science Foundation and European Research Council.
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Helmintiasis/epidemiología , Parasitosis Intestinales/epidemiología , Enfermedades Desatendidas/epidemiología , África del Sur del Sahara/epidemiología , Ancylostomatoidea/aislamiento & purificación , Animales , Antihelmínticos/uso terapéutico , Ascaris lumbricoides/aislamiento & purificación , Helmintiasis/tratamiento farmacológico , Helmintiasis/parasitología , Helmintiasis/prevención & control , Humanos , Parasitosis Intestinales/tratamiento farmacológico , Parasitosis Intestinales/parasitología , Parasitosis Intestinales/prevención & control , Enfermedades Desatendidas/tratamiento farmacológico , Enfermedades Desatendidas/parasitología , Enfermedades Desatendidas/prevención & control , Prevalencia , Análisis Espacio-Temporal , Trichuris/aislamiento & purificaciónRESUMEN
The need to engage the public in Neglected Tropical Diseases (NTDs) control activities has become imperative in the context of morbidity reduction through preventive chemotherapy and community participation. Therefore, a survey was conducted among the general public to assess their knowledge and awareness of NTDs control activities in Nigeria. A simple questionnaire was administered to the general public attending a job fair in Abuja, Nigeria. Of the 461 respondents, a significant proportion 337 (73.1%) have heard of NTD before, but only 291 (63.1%) have good knowledge about NTDs. However, among the specific NTDs, only the control of onchocerciasis (50.8%) was of average public awareness in Nigeria, while all the other NTDs control activities were significantly less known to the general public. 397 (87.1%) stated that government support for NTD control activities is poor and were willing to assist to advocate for NTDs control. This survey demonstrates that despite government's numerous activities towards the control of NTDs in Nigeria, there is little sensitization of the general public. There is a need for policy changes that would raise the participation and involvement of the general public in NTDs control activities for sustainability.
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Conocimientos, Actitudes y Práctica en Salud , Enfermedades Desatendidas/epidemiología , Enfermedades Desatendidas/prevención & control , Adulto , Estudios Transversales , Femenino , Educación en Salud , Humanos , Masculino , Persona de Mediana Edad , Nigeria/epidemiología , Salud Pública , Adulto JovenRESUMEN
Schistosomiasis prevalence data for Nigeria were extracted from peer-reviewed journals and reports, geo-referenced and collated in a nationwide geographical information system database for the generation of point prevalence maps. This exercise revealed that the disease is endemic in 35 of the country's 36 states, including the federal capital territory of Abuja, and found in 462 unique locations out of 833 different survey locations. Schistosoma haematobium, the predominant species in Nigeria, was found in 368 locations (79.8%) covering 31 states, S. mansoni in 78 (16.7%) locations in 22 states and S. intercalatum in 17 (3.7%) locations in two states. S. haematobium and S. mansoni were found to be co-endemic in 22 states, while co-occurrence of all three species was only seen in one state (Rivers). The average prevalence for each species at each survey location varied between 0.5% and 100% for S. haematobium, 0.2% to 87% for S. mansoni and 1% to 10% for S. intercalatum. The estimated prevalence of S. haematobium, based on Bayesian geospatial predictive modelling with a set of bioclimatic variables, ranged from 0.2% to 75% with a mean prevalence of 23% for the country as a whole (95% confidence interval (CI): 22.8-23.1%). The model suggests that the mean temperature, annual precipitation and soil acidity significantly influence the spatial distribution. Prevalence estimates, adjusted for school-aged children in 2010, showed that the prevalence is <10% in most states with a few reaching as high as 50%. It was estimated that 11.3 million children require praziquantel annually (95% CI: 10.3-12.2 million).
Asunto(s)
Teorema de Bayes , Modelos Teóricos , Esquistosomiasis/epidemiología , Análisis Espacial , Antihelmínticos/uso terapéutico , Sistemas de Información Geográfica , Humanos , Nigeria/epidemiología , Praziquantel/uso terapéutico , Prevalencia , Riesgo , Esquistosomiasis/tratamiento farmacológico , Factores de Tiempo , Tiempo (Meteorología)RESUMEN
BACKGROUND: After many years of general neglect, interest has grown and efforts came under way for the mapping, control, surveillance, and eventual elimination of neglected tropical diseases (NTDs). Disease risk estimates are a key feature to target control interventions, and serve as a benchmark for monitoring and evaluation. What is currently missing is a georeferenced global database for NTDs providing open-access to the available survey data that is constantly updated and can be utilized by researchers and disease control managers to support other relevant stakeholders. We describe the steps taken toward the development of such a database that can be employed for spatial disease risk modeling and control of NTDs. METHODOLOGY: With an emphasis on schistosomiasis in Africa, we systematically searched the literature (peer-reviewed journals and 'grey literature'), contacted Ministries of Health and research institutions in schistosomiasis-endemic countries for location-specific prevalence data and survey details (e.g., study population, year of survey and diagnostic techniques). The data were extracted, georeferenced, and stored in a MySQL database with a web interface allowing free database access and data management. PRINCIPAL FINDINGS: At the beginning of 2011, our database contained more than 12,000 georeferenced schistosomiasis survey locations from 35 African countries available under http://www.gntd.org. Currently, the database is expanded to a global repository, including a host of other NTDs, e.g. soil-transmitted helminthiasis and leishmaniasis. CONCLUSIONS: An open-access, spatially explicit NTD database offers unique opportunities for disease risk modeling, targeting control interventions, disease monitoring, and surveillance. Moreover, it allows for detailed geostatistical analyses of disease distribution in space and time. With an initial focus on schistosomiasis in Africa, we demonstrate the proof-of-concept that the establishment and running of a global NTD database is feasible and should be expanded without delay.
Asunto(s)
Sistemas de Administración de Bases de Datos , Bases de Datos Factuales , Enfermedades Desatendidas/epidemiología , Esquistosomiasis/epidemiología , Clima Tropical , Adolescente , Adulto , África/epidemiología , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Salud Global , Humanos , Lactante , Recién Nacido , Internet , Persona de Mediana Edad , PrevalenciaRESUMEN
BACKGROUND: The control of schistosomiasis in Nigeria is mainly by mass treatment with praziquantel through the school system, with an absence of any provision for pre-school children. We therefore determined the prevalence and intensity of urinary schistosomiasis in pre-school children between the ages of 1-6 years in Ilewo-Orile a rural and endemic community, near Abeokuta, Nigeria as part of providing information on the neglected tropical diseases among this age group. Two urine samples were collected from each pre-school child. The samples were tested for microhaematuria using reagent strips and then processed and examined with a microscope for Schistosoma haematobium ova. RESULTS: Of the 167 children examined 97 (58.1%) had infection, with no significant difference (P = 0.809) in infection rates between boys (57.1%) and girls (59.2%). Both prevalence and intensity of infection did not increase significantly with age (P = 0.732). The overall geometric mean egg count was 1.17 eggs/10 ml urine. There was no significant association (P = 0.387) between intensity in boys (1.16 eggs/10 ml urine) and girls (1.19 eggs/10 ml urine). 47.4% of the children had microhaematuria which did not increase significantly with age (P = 0.526). Focus group discussions with guardians and caregivers revealed that infection of pre-school children early in life was due to exposures through bathing in the stream by their mothers, while the older children would visit the stream for washing, fetching of water, bathing and swimming. CONCLUSION: Community participatory health education is needed in this community as a first step in reducing infection and transmission of the disease, while the rehabilitation and repair of the existing water borehole system in the community should be effected. The results of this study have shown that pre-school children also harbour infection and are a source of transmission of schistosomiasis in endemic communities. Planning and provision for their treatment should be considered in control programmes.
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BACKGROUND: Studies on biting behaviours and infectivity status of insect vectors are pre-requisites in understanding the epidemiology of the vector- borne diseases and planning effective control measures. A longitudinal study was carried out to investigate the transmission index of Simulium damnosum complex species along Osun River, South Western Nigeria. Adult flies were collected on human attractants from 07:00 to 18:00 hours for two consecutive days from February 2008 to June 2009 at three communities: Osun Eleja, Osun Ogbere and Osun Budepo. The infectivity rate was determined by dissection and Polymerase Chain Reaction amplification (PCR) of 0-150 genes of Onchocerca parasite using the pool screening technique. RESULTS: The results indicated that the majority of the flies collected at the three sampling points were nulliparous as they accounted for 53.90%, 57.86% and 59.58% of the flies dissected at Osun Budepo, Osun Ogbere and Osun Eleja, respectively. The parous rate was higher during the dry season than the wet season but the difference was not statistically significant (p < 0.05). The biting activity of the parous flies showed two peaks at Osun Budepo and three peaks at Osun Eleja and Osun Ogbere. Of the 1,472 flies dissected and 1,235 flies screened by molecular method, none was infected with Onchocerca parasite at the three sampling points however the annual biting rates at the three communities were higher than 1,000 considered as tolerable value for a person living in an onchocerciasis zone by Word Health Organization. CONCLUSION: The study has provided the baseline data for further study on onchocerciasis transmission dynamics and the need to intercept man- simuliid vector contact at the study area.
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BACKGROUND: Simulum damnosum Theobald sensu lato (s.l.) is the vector of the parasitic filarial worm Onchocerca volvulus Leuckart which causes onchocerciasis. In order to understand the vector population dynamics, a preliminary 12 months entomological evaluation was carried out at Abeokuta, the Southwest Zone of Nigeria, an onchocerciasis endemic area, where vector control has not been previously initiated. S.damnosum s.l. flies were caught on human attractants between 700 to1800 hours each day, for 4 days each month, from August 2007 to July 2008. The flies caught were classified as either forest-dwelling or savanna-dwelling groups based on the colour of certain morphological characters. Climatic data such as rainfall, humidity and temperature were also collected monthly during the period of survey. RESULTS: A total of 1,139 flies were caught, 596 (52.33%) were forest-dwelling group while 543 (47.67%) were savanna-dwelling group of S. damnosum s.l. The highest percentage of forest-dwelling group was caught in the month of August 2007 (78.06%) and the least percentage of forest-dwelling groups was caught in November 2007 (8.14%). The highest percentage of savannah-dwelling group was caught in the month of November 2007 (91.86%) and the least percentage of savannah-dwelling group was caught in August 2007 (21.94%). There was no significant difference between the population of forest and savannah-dwelling groups of the fly when the means of the fly population were compared (P = 0.830). Spearman correlation analysis showed a significant relationship between monthly fly population with monthly average rainfall (r = 0.550, n = 12, P = 0.033), but no significant relationship with monthly average temperature (r = 0.291, n = 12, P = 0.179). There was also a significant relationship between monthly fly population and monthly average relative humidity (r = 0.783, n = 12 P = 0.001). There was no significant correlation between the population of forest-dwelling group of S. damnosum s.l. and monthly average rainfall (r = 0.466, n = 12, P = 0.064) and monthly average temperature (r = 0.375, n = 12, P = 0.115) but there was significant correlation with monthly average relative humidity (r = 0.69, n = 12, P = 0.006). There was significant correlation between savannah-dwelling group and monthly average rainfall (r = 0.547, n = 12, P = 0.033), and monthly average relative humidity (r = 0.504, n = 12, P = 0.047) but there was no significant correlation with monthly average temperature (r = 0.142, n = 12, P = 0.329) CONCLUSION: The results from this study showed that both the forest and the savannah dwelling groups of S. damnosum s.l. were caught biting in the study area. This could have implications on the transmission and epidemiology of human onchocerciasis if not monitored.