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.

SUMMARY: 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.

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. 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. 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. 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. Infections with three kinds of parasitic worms—hookworm, roundworm, and whipworm—are collectively known as soil-transmitted helminths (STHs). These parasitic worm infections are widespread in Nigeria, but the exact distribution is poorly understood. In view of the global commitment to control STH infections, there is a need to accelerate the mapping of STH infections to guide control interventions, such as large-scale administration of deworming drugs. In this study, we collated survey data from the year 2011 for Nigeria. The data were utilized to predict the distribution of STH infection based on environmental and socioeconomic covariates, and employing a Bayesian geostatistical modeling approach. Our results indicated that STH infections are widely distributed across Nigeria with prevalence estimates as high as 83% for roundworm, 50% for hookworm, and 19% for whipworm infections at specific survey locations. We predict that 5.7 million school-aged children were infected with STHs. The numbers of deworming tablets for annual or bi-annual treatment of the school-aged population at local government areas level in Nigeria for 2011 were estimated to be 10.2 million.

Mapping and prediction of schistosomiasis in Nigeria using compiled survey data and Bayesian geospatial modelling

SUMMARY: The Nigerian national control programme (NCP) for schistosomiasis does not have a specific action plan for female genital schistosomiasis (FGS), mainly due to gaps in epidemiological and clinical surveillance. To address this, we conducted a pilot investigation for FGS in girls (>5 and ≤15 years) and adult women (≥16 years) in four rural communities near Abeokuta, Ogun State. Urine samples were collected from 317 participants [children (n = 187), adults (n = 130)] and examined for ova of S chistosoma haematobium by microscopy. A total of 149 participants (47·0%) had egg-patent urogenital schistosomiasis [children (64·7%), adults (21·6%)], reported blood in urine was common (44·5%) as well as sign-post symptoms of FGS. To verify FGS directly, 20 adult women each underwent a gynaecological investigation by colposcopy with observed lesions classified according to the WHO FGS pocket atlas. Fourteen (70·0%) women presented with FGS as grainy-sandy patches (n = 10), homogenous yellow sandy patches (n = 6), nabothian cysts and rubbery papules (n = 1). Our study confirms FGS in Ogun State and calls for further appraisals of this disease in other areas where urogenital schistosomiasis is endemic. The Nigerian NCP should be encouraged to develop an appropriate response to FGS not only to detect it, but also to prevent it.