High prevalence of Schistosoma mansoni infection and stunting among school age children in communities along the Albert-Nile, Northern Uganda: A cross sectional study

BackgroundKnowing the prevalence of schistosomiasis is key to informing programmes to control and eliminate the disease as a public health problem. It is also important to understand the impact of infection on child growth and development in order to allocate appropriate resources and effort to the control of the disease.MethodsWe conducted a survey to estimate the prevalence of schistosomiasis among school aged children in villages along the Albert-Nile shore line in the district of Pakwach, North Western Uganda. A total of 914 children aged between 10-15 years were screened for Schistosoma mansoni using the POC-CCA and Kato Katz (KK) techniques. The infection intensities were assessed by POC-CCA and KK as well as CAA tests. The KK intensities were also correlated with POC-CCA and with CAA intensity. Anthropometric measurements were also taken and multivariate analysis was carried out to investigate their association with infection status.ResultsThe prevalence of schistosomiasis using the POC-CCA diagnostic test was estimated at 85% (95% CI: 83-87), being highest amongst children living closer to the Albert-Nile shoreline. Visual scoring of the POC-CCA results was more sensitive than the Kato Katz test and was positively correlated with the quantified infection intensities by the CAA test. The majority of the children were underweight (BMI< 18.5), and most notably, boys had significantly lower height for age (stunting) than girls in the same age range (p < 0.0001), but this was not directly associated with S. mansoni infection.ConclusionHigh prevalence of S. mansoni infection in the region calls for more frequent mass drug administration with praziquantel. We observed high levels of stunting which was not associated with schistosomiasis. There is a need for improved nutrition among the children in the area.Author summarySchistosomiasis is a neglected but frequent disease that is caused by schistosomes, with over 290 million people worldwide at risk of infection. The major mode of transmission is through contact with fresh water sources infested with infected snails (the intermediate host). In this study, using the point of care test (POC-CCA), we screened 914 school aged children (10-15 years) living in the rural communities along the Lake Albert- River Nile shores of Pakwach district in Northern Uganda. We observed a very high prevalence of S. mansoni infections (over 80%) although the prevalence dropped to 40% in communities that were further from the lake shores. This high prevalence was also coupled with Kato Katz light schistosome infection intensities as categorised by WHO guidelines. We further compared the POC-CCA and Kato Katz tests to the more sensitive CAA assay and this revealed that even though both tests gave good probability of positive prediction, the POC-CCA had higher sensitivity in screening for S. mansoni infections than Kato Katz assay. The study also revealed high levels of stunting within the children, more so amongst boys. Frequent screening and mass treatment of these communities with praziquantel will reduce on the infection rates. But in addition, improved hygiene and sanitation will be required for a sustainable reduction in the prevalence and morbidity of schistosomiasis in the Albert-Nile communities along with dietary intervention for optimal child health