Data on the pre-MDA and post MDA interventions for Schistosoma mansoni and Schistosoma haematobium in a co-endemic focus in Uganda: 1951-2011.

The dataset for this article contains Urinary and Intestinal Schistosomiasis from Lango region, northern Uganda which is the only known co-endemic region for S.mansoni and S.haematobium. Reported in the data, is the retrospective data review for historical information before interventions were implemented before 2003 and after interventions were implemented in 2003 by the national control program. In 2007 and 2011, parasitological surveys were conducted in the region to validate Schistosomiasis trends following World Health Organization (WHO) guidelines for surveys. In addition, malacological surveys were undertaken in 2007 to assess local transmission potential. The dataset can provide an insight into the health implications of Schistosomiasis control in co-endemic focus in Uganda, "The epidemiology of schistosomiasis in Lango region Uganda 60 years after Schwetz 1951: Can schistosomiasis be eliminated through mass drug administration without other supportive control measures?" (Adriko et al., 2018) [10].

The epidemiology of schistosomiasis in Lango region Uganda 60 years after Schwetz 1951: Can schistosomiasis be eliminated through mass drug administration without other supportive control measures?

INTRODUCTION: Lango region is the only known endemic region for urinary and intestinal schistosomiasis in Uganda. Although there has been no significant improvement in sanitation and safe water supply in the region over years, the endemicity and prevalence of Schistosoma haematobium, in particular, have declined, perhaps due to yearly mass treatment campaigns implemented since 2003. METHODS: We report the epidemiology of Urinary and Intestinal schistosomiasis in Lango since 1951-2011 determined through Microscopic examinations for S. mansoni and S. haematobium respectively. A retrospective data review from 195 to 2011 was done to establish the prevalence over the years in the region. We performed Poisson regression analysis to observe trends in epidemiology before and after control was initiated in 2002. In addition, malacological surveys were undertaken in 2007 to assess local transmission potential. FINDINGS: Contrary to earlier records, S. haematobium was low and confined to a few putative foci, with declined in infections from 28.2% in 1951 to 2.48% by 2011. Although this decline can be attributed to control, this was already much lower in 1967 than 1951, long before control interventions began suggesting that environmental changes may have made the habitat less suitable for the transmission of S. haematobium. Compared to the historical records S. mansoni prevalence first increased up immediately before control interventions in 2003, significantly declined (p=<0.001) until 2007. However, in 2007 and 2011 declined insignificant, (p = 0.656). No snail has ever been isolated shedding S. haematobium cercariae but many Bulinus snail spp. were found shedding S. bovis cercariae. CONCLUSION: This suggests that a combination of environmental and mass treatment has had a significant impact on transmission in Lango region.

Evaluation of circulating cathodic antigen (CCA) urine-cassette assay as a survey tool for Schistosoma mansoni in different transmission settings within Bugiri District, Uganda.

Diagnosis of schistosomiasis at the point-of-care (POC) is a growing topic in neglected tropical disease research. There is a need for diagnostic tests which are affordable, sensitive, specific, user-friendly, rapid, equipment-free and delivered to those who need it, and POC is an important tool for disease mapping and guiding mass deworming. The aim of present study was to evaluate the relative diagnostic performance of two urine-circulating cathodic antigen (CCA) cassette assays, one commercially available and the other in experimental production, against results obtained using the standard Kato-Katz faecal smear method (six thick smears from three consecutive days), as a 'gold-standard', for Schistosoma mansoni infection in different transmission settings in Uganda. Our study was conducted among 500 school children randomly selected across 5 schools within Bugiri district, adjacent to Lake Victoria in Uganda. Considering results from the 469 pupils who provided three stool samples for the six Kato-Katz smears, 293 (76%) children had no infection, 109 (23%) were in the light intensity category, while 42 (9%) and 25 (5%) were in the moderate and heavy intensity categories respectively. Following performance analysis of CCA tests in terms of sensitivity, specificity, negative and positive predictive values, overall performance of the commercially available CCA test was more informative than single Kato-Katz faecal smear microscopy, the current operational field standard for disease mapping. The current CCA assay is therefore a satisfactory method for surveillance of S. mansoni in an area where disease endemicity is declining due to control interventions. With the recent resolution on schistosomiasis elimination by the 65th World Health Assembly, the urine POC CCA test is an attractive tool to augment and perhaps replace the Kato-Katz sampling within ongoing control programmes.

Intestinal schistosomiasis in chimpanzees on Ngamba Island, Uganda: observations on liver fibrosis, schistosome genetic diversity and praziquantel treatment.

Despite treatment with praziquantel (PZQ) at 40 mg/kg in food, several chimpanzees on Ngamba Island Chimpanzee Sanctuary (NICS) continue to excrete eggs of Schistosoma mansoni. To monitor disease, 8 animals were closely examined under anaesthesia in March 2011 with portable ultrasonography and by rectal snip biopsy. Schistosome genetic diversity had been previously assayed within 4 of these chimpanzees, finding extensive diversity with 27 DNA barcodes encountered, although none was common to all animals. Calcified schistosome eggs were found in the rectal snips from 5 chimpanzees and liver fibrosis was clearly documented, indicative of progressive disease in 6 animals, the latter being surprisingly advanced in a younger chimpanzee. All 8 animals were treated under anaesthesia by oral gavage with PZQ at 60 mg/kg dosing that was well tolerated. These animals were again re-examined in June 2012 using stool and urine sampling. Only 1 chimpanzee appeared to be free from infection and active egg excretion was confirmed in 6 animals. If intestinal schistosomiasis is to be controlled within this setting, a long-term disease management plan is required which should combine active case-detection with an insistent treatment regime with praziquantel for these chimpanzees, exploring perhaps the performance of even higher dosing.

DNA barcoding of schistosome cercariae reveals a novel sub-lineage within Schistosoma rodhaini from Ngamba Island Chimpanzee Sanctuary, Lake Victoria.

While Schistosoma rodhaini is typically considered a parasite of small mammals and is very scantly distributed in the Lake Victoria basin, it is known to hybridize with the more widespread Schistosoma mansoni, the causative agent of intestinal schistosomiasis. As part of broader parasitological and malacological surveys for S. mansoni across Lake Victoria, schistosome cercariae were harvested from a field-caught Biomphalaria choanomphala taken on Ngamba Island Chimpanzee Sanctuary, Uganda. Upon DNA barcoding, these cercariae were found to be a mixture of both S. rodhaini and S. mansoni, with further phylogenetic analysis revealing a hitherto unknown sub-lineage within S. rodhaini. Despite repeated sampling for eggs and miracidia from both chimpanzees and staff on Ngamba Island Sanctuary, detection of S. rodhaini within local definitive hosts awaits additional efforts, which should be mindful of a potential host role of spotted-necked otters.

Zoonotic schistosomiasis in non-human primates: past, present and future activities at the human-wildlife interface in Africa.

Schistosomiasis is one of the world's most widely distributed and prevalent parasitic diseases. Less widely recognized is that some species of Schistosoma, including several that commonly affect humans, also cause disease in other mammalian species; in particular, infections in non-human primates are known. With interest increasing in emerging zoonotic diseases, the status of schistosomiasis as a zoonotic infection is in need of re-appraisal, especially in light of advances in application of molecular screening and epidemiological tools where newly reported infections raise general animal welfare and conservation concerns. Focusing on Africa, this review provides a summary of the occurrence of schistosomiasis in non-human primates and discusses new ways in which surveillance for schistosomiasis should be integrated into more effective conservation management and disease control strategies. Emphasis is on the more common forms of human schistosomiasis, their clinical manifestations and epidemiological significance in terms of infection reservoir potential.

Molecular epidemiology and phylogeography of Schistosoma mansoni around Lake Victoria.

Intestinal schistosomiasis continues to be a major public health problem in sub-Saharan Africa, and is endemic in communities around Lake Victoria. Interest is growing in the molecular evolution and population genetic structure of Schistosoma mansoni and we describe a detailed analysis of the molecular epidemiology and phylogeography of S. mansoni from Lake Victoria. In total, 388 cytochrome oxidase 1 (COI) sequences were obtained from 25 sites along the Ugandan, Tanzanian and Kenyan shorelines of Lake Victoria, and 122 unique barcodes were identified; 9 corresponded to previously discovered barcodes from Lakes Victoria and Albert. A subset of the data, composed of COI sequences from miracidia from 10 individual children, was used for population genetics analyses; these results were corroborated by microsatellite analysis of 4 isolates of lab-passaged adult worms. Overall, 12 barcodes were found to be shared across all 3 countries, whereas the majority occurred singly and were locally restricted. The population genetics analyses were in agreement in revealing high diversity at the level of the human host and negligible population structuring by location. The lack of correlation between genetic distance and geographical distance in these data may be attributed to the confounding influence of high intra-individual diversity as well as human migration between communities.

Performance of circulating cathodic antigen (CCA) urine-dipsticks for rapid detection of intestinal schistosomiasis in schoolchildren from shoreline communities of Lake Victoria.

ABSTRACT: For disease surveillance and mapping within large-scale control programmes, RDTs are becoming popular. For intestinal schistosomiasis, a commercially available urine-dipstick which detects schistosome circulating cathodic antigen (CCA) in host urine is being increasingly applied, however, further validation is needed. In this study, we compared the CCA urine-dipstick test against double thick Kato-Katz faecal smears from 171 schoolchildren examined along the Tanzanian and Kenyan shorelines of Lake Victoria. Diagnostic methods were in broad agreement; the mean prevalence of intestinal schistosomiasis inferred by Kato-Katz examination was 68.6% (95% confidence intervals (CIs) = 60.7-75.7%) and 71.3% (95% CIs = 63.9-78.8%) by CCA urine-dipsticks. There were, however, difficulties in precisely 'calling' the CCA test result, particularly in discrimination of 'trace' reactions as either putative infection positive or putative infection negative, which has important bearing upon estimation of mean infection prevalence; considering 'trace' as infection positive mean prevalence was 94.2% (95% CIs = 89.5-97.2%). A positive association between increasing intensity of the CCA urine-dipstick test band and faecal egg count was observed. Assigning trace reactions as putative infection negative, overall diagnostic sensitivity (SS) of the CCA urine-dipstick was 87.7% (95% CIs = 80.6-93.0%), specificity (SP) was 68.1% (95% CIs = 54.3-80.0%), positive predictive value (PPV) was 86.1% (95% CIs = 78.8-91.7%) and negative predictive value (NPV) was 71.1% (95% CIs = 57.2-82.8%). To assist in objective defining of the CCA urine-dipstick result, we propose the use of a simple colour chart and conclude that the CCA urine-dipstick is a satisfactory alternative, or supplement, to Kato-Katz examination for rapid detection of intestinal schistosomiasis.