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Introduction: Schistosomiasis (SCH) and soil transmitted helminthiases (STH) have been historically recognized as a major public health problem in Angola. However, lack of reliable, country wide prevalence data on these diseases has been a major hurdle to plan and implement programme actions to target these diseases. This study aimed to characterize SCH and STH prevalence and distribution in Angola. Methods: A country wide mapping was conducted in October 2018 (1 province) and from July to December 2019 (14 provinces) in school aged (SAC) children in 15 (of 18) provinces in Angola, using WHO protocols and procedures. A total of 640 schools and an average of 50 students per school (N = 31,938 children) were sampled. Stool and urine samples were collected and processed using the Kato-Katz method and Urine Filtration. Prevalence estimates for SCH and STH infections were calculated for each province and district with 95% confidence intervals. Factors associated with SCH and STH infection, respectively, were explored using multivariable logistic regression accounting for clustering by school. Results: Of the 131 districts surveyed, 112 (85.5%) are endemic for STH, 30 (22.9%) have a prevalence above 50%, 24 (18.3%) are at moderate risk (prevalence 20%-50%), and 58 (44.3%) are at low risk (<20% prevalence); similarly, 118 (90,1%) of surveyed districts are endemic for any SCH, 2 (1.5%) are at high risk (>50% prevalence), 59 (45.0%) are at moderate risk (10%-50% prevalence), and 57 (43.5%) are at low risk (<10% prevalence). There were higher STH infection rates in the northern provinces of Malanje and Lunda Norte, and higher SCH infection rates in the southern provinces of Benguela and Huila. Conclusions: This mapping exercise provides essential information to Ministry of Health in Angola to accurately plan and implement SCH and STH control activities in the upcoming years. Data also provides a useful baseline contribution for Angola to track its progress towards the 2030 NTD roadmap targets set by WHO. Author summary: Neglected Tropical Diseases (NTD) still affect nearly 1 billion people worldwide and are a major public health problem in Angola. Schistosomiasis (SCH) and soil transmitted Helminthiases (STH) affect disproportionally school aged children (SAC). In endemic areas, implementation of preventive chemoprevention through school-based Mass Drug Administration Campaigns is a key strategy used to reduce the burden of these infections. Mapping of schistosomiasis and soil transmitted helminthiases is essential to know where transmission occurs and is used to inform interventions planning. A country wide SCH and STH mapping was conducted across 15 of the 18 provinces of Angola. Parasitological analysis of nearly 32,000 children was conducted to detect SCH and STH infections and determine the prevalence of these diseases. Eighty Six percent of the mapped districts are endemic for STH and 22.9% have a prevalence above 50%. Similarly, 90% of surveyed districts are endemic for SCH. There were higher STH infection rates in the northern provinces of Malanje and Lunda Norte, and higher SCH infection rates in the southern provinces of Benguela and Huila. These results are of vital importance to map the prevalence of SCH and STH in Angola and to plan adequate interventions that support NTD control across the country. [ABSTRACT FROM AUTHOR]

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. Author Summary: Schistosomiasis (SCH) is a parasitic infection and one gets infected when bathing or in contact with contaminated fresh water bodies like rivers. It has been shown that people living in poor sanitary conditions and especially school-aged children suffer the most from this infection. Mapping is needed in order to control or prevent the disease. However, in the Democratic Republic of the Congo (DRC), surveillance of schistosomiasis is lacking. Previous data on distribution of schistosomiasis may have lost relevance since the disease was last mapped 20 years ago. This study was carried out in 2011 in the health zone of Kasansa, DRC. Six primary schools were visited and stool samples were collected from children attending the 3rd class. The stool samples were analyzed for S. mansoni infection. Up to 335 children were recruited and 82.7% were infected. Moreover, in 4 health areas over 91% of the children were infected. Of all infected children, almost 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 put effective control measures. [ABSTRACT FROM AUTHOR]

Background Schistosomiasis (SCH) and soil-transmitted helminthiasis (STH) are widely distributed in the Democratic Republic of the Congo (DRC) and constitute a serious public health problem. As recommended by the World Health Organization (WHO), before launching mass chemotherapy to control these diseases, parasitological surveys were conducted in sentinel sites in six health zones (HZs) in Bandundu and Maniema provinces. Baseline prevalence and intensity of infection for SCH and STH were determined to establish the appropriate treatment plan using Praziquantel (PZQ) and Albendazole (ALB). Methods Parasitological surveys were conducted from April to May 2015 in twenty-six selected sampling units (schools) for baseline mapping in six HZs: Fifty school children (25 females and 25 males) aged 9–15 years were randomly selected per sampling unit. A total of 1300 samples (urine and stool) were examined using haematuria dipsticks, parasite-egg filtration and the point-of-care Circulating Cathodic Antigen (POC-CCA) assay for urine samples and the Kato-Katz technique for stool specimens. Results Three species of schistosomes ( S. mansoni , S. haematobium and S. intercalatum ) and three groups of STH (hookworm, Ascaris and Trichuris ) were detected at variable prevalence and intensity among the schools, the HZs and the provinces. In Bandundu, no SCH was detected by either Kato-Katz or the POC-CCA technique, despite a high prevalence of STH with 68% and 80% at Kiri and Pendjua HZs, respectively. In Maniema, intestinal schistosomiasis was detected by both Kato-Katz and POC-CCA with an average prevalence by Kato-Katz of 32.8% and by POC-CCA of 42.1%. Comparative studies confirmed the greater sensitivity (and operational feasibility) of the POC-CCA test on urine compared to Kato-Katz examination of stool for diagnosing intestinal schistosomiasis even in areas of comparatively light infections. STH was widely distributed and present in all HZs with a mean prevalence (95% CI) of 59.62% (46.00–65.00%). The prevalence of hookworm, roundworm and whipworm were 51.62% (32.40%–71.50%), 15.77% (0.50%–39.60%) and 13.46 (0.50%–33.20%), respectively. Conclusion This study provided the evidence base for implementing programs targeting SCH and STH in these Health Zones. Observations also reinforce the operational value and feasibility of the POC-CCA test to detect S. mansoni and, for the first time, S. intercalatum infections in a routine NTD program setting. [ABSTRACT FROM AUTHOR]