EPIDEMIOLOGY OF INTESTINAL HELMINTH INFESTATIONS AMONG SCHOOLCHILDREN IN SOUTHERN UGANDA

Objective: To determine the prevalence and intensity of intestinal helminth species amongschool children in southern Uganda.Design: A cross-sectional survey using a randomly selected sample.Setting: Eighteen districts of southern Uganda,Subject: Two thousand and four school children aged two to twenty years (93.3 %, aged 5-10years) selected from classes 1 and 2 in 26 randomly selected primary schools.Results: Overall, 55.9 % of children were infected with either hookworm,Ascarislumbricotdesor Trichuris trichiura. The prevalence of A. lurnbricoides was 17.5% ( range 0-66.7% byschtml), T. trichiura was 7.3% (0 - 45.0%) and hookworm 44.5% (15.6-86.0%). Theprevalence of A. lumbricoides and T. trichiura was greatest in western districts whilehookworm infection was more evenly distributed across the country.Conclusion: Mass antihelminthic treatment of school children was warranted in 13 of the 18districts as more than 50% of the children were infected with an intestinal nematode. It islikely that pre-school children are similarly infected

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 EFFECT OF SEASONAL RAINFALL AND OTHER ENVIRONMENTAL CHANGES, ON SNAIL DENSITY AND INFECTION RATES WITH SCHISTOSOMA MANSONI FIFTEEN YEARS AFTER THE LAST SNAILS’ STUDY IN KIGUNGU, ENTEBBE, UGANDA

Background: The last study on snail population density in relation to rainfall pattern in Kigungu canoe landing and recreational sites on Lake Victoria shore was earlier carried out about a fi fteen years ago. This study also reviewed the infl uence of other environmental factors on the snails’ infection rate.Objective: To reassess the density dynamic of Biomphalaria (B) choanomphala and Biomphalaria (B) pfeifferi, which act as the intermediate host for S. mansoni and Bulinus (B) globosus, and Bulinus (B) tropicus, which act as intermediate host for S. haematobium.Design: Retrospective study.Setting: Busy canoe landing sites along Lake Victoria in Kigungu fi shing village were selected for the snail sampling.Results: Nine thousand one hundred and ninety four B. choanomphala were collected over the study period. The numbers of B. choanomphala collected in each year was 4742 (51.6%) and 4452 (48.4%) in 2004 and 2005 respectively. Of the 4742 B.Choanomphala collected in 2004,82 (1.7%) shed human cercariae and 329 (6.7%) shed non-human cercariae. Whereas in 2005, out of 4452 B. choanomphala collected 302 (6.85<%) shednon-human cercariae and 82 (1.8%) shed human cercariae. Similarly, 4173 B. pfeifferi were also collected in the same period. Out of which 2224 (53.3%)) were collected in 2004 and 1949 (46.7%) in 2005. For B. pfeifferi, 42 (1.9%) out of 2224 snails collected in 2004 shed human cercariae and 246 (11.1(%) shed non-human cercariae. While in 2005, 33 outof 1949 snails (1.7%) shed human ccrcariae and 159 (8.2%) shed  non-human cercariae. Other snails of medical importance collected included 292 B. globosus and 3094 B. tropicus. None of the Bulinus spp. collected shed any human cercariae but 37 (2.1 %) and 30 (2.3%) B. tropicus shed non-human cercariae in 2004 and 2005 respectively. In 2004 and 2005, the area received, 1729mm and 1959mm of rainfall respectively. The meanrainfall during the year was 144.05 mm and 163.3 mm in 2004 and 2005 respectively. There was a negative correlation between rainfalls and snail density dynamic.Conclusion: We have found in this study that in spite of the bush clearing of the papyrus swamps which originally was the major habitats for B. choanomphala, B. pfeifferi and the Bulinus spp the intermediate host for schistosome at all canoe landing sites at Kigungu, these snails are still present. Moreover, that their population density dynamic and infection rate are inversely proportional to the rainfall pattern

Development and application of an ethically and epidemiologically advantageous assay for the multi-locus microsatellite analysis of Schistosoma mansoni

Non-availability of adult worms from living hosts remains a key problem in population genetic studies of schistosomes. Indirect sampling involving passage through laboratory animals presents significant ethical and practical drawbacks, and may result in sampling biases such as bottlenecking processes and/or host-induced selection pressures. The novel techniques reported here for sampling, storage and multi-locus microsatellite analysis of larval Schistosoma mansoni, allowing genotyping of up to 7 microsatellite loci from a single larva, circumvent these problems. The utility of these assays and the potential problems of laboratory passage, were evaluated using 7 S. mansoni population isolates collected from school-children in the Hoima district of Uganda, by comparing the associated field-collected miracidia with adult worms and miracidia obtained from a single generation in laboratory mice. Analyses of laboratory-passaged material erroneously indicated the presence of geographical structuring in the population, emphasizing the dangers of indirect sampling for population genetic studies. Bottlenecking and/or other sampling effects were demonstrated by reduced variability of adult worms compared to their parent field-collected larval samples. Patterns of heterozygote deficiency were apparent in the field-collected samples, which were not evident in laboratory-derived samples, potentially indicative of heterozygote advantage in establishment within laboratory hosts. Genetic distance between life-cycle stages in the majority of isolates revealed that adult worms and laboratory-passaged miracidia clustered together whilst segregating from field miracidia, thereby further highlighting the utility of this assay

Differential Anti-Glycan Antibody Responses in Schistosoma mansoni-Infected Children and Adults Studied by Shotgun Glycan Microarray

Host-parasite interactio

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