Browsing by Author "Adriko, Moses"

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    Ethical and Scientific Considerations on the Establishment of a Controlled Human Infection Model for Schistosomiasis in Uganda: report of a stakeholders’ meeting held in Entebbe, Uganda.
    (AAS open research, 2018) Elliott, Alison M.; Wajja, Anne; Opio, Christopher; Angumya, Francis; Adriko, Moses; Egesa, Moses; Mfutso-Bengo, Joseph; Kapulu, Melissa; Lutalo, Tom; Nazziwa, Winfred Badanga; Muwumuza, Asuman; Kaleebu, Pontiano; Kabatereine, Narcis; Tukahebwa, Edridah
    Controlled human infection (CHI) models are gaining recognition as an approach to accelerating vaccine development, for use in both non-endemic and endemic populations: they can facilitate identification of the most promising candidate vaccines for further trials and advance understanding of protective immunity. Helminths present a continuing health burden in sub-Saharan Africa. Vaccine development for these complex organisms is particularly challenging, partly because protective responses are akin to mechanisms of allergy. A CHI model for Schistosoma mansoni (CHI-S) has been developed at Leiden University Medical Centre, the Netherlands. However, responses to schistosome infections, and candidate vaccines, are likely to be different among people from endemic settings compared to schistosome-naïve Dutch volunteers. Furthermore, among volunteers from endemic regions who have acquired immune responses through prior exposure, schistosome challenge can be used to define responses associated with clinical protection, and thus to guide vaccine development. To explore the possibility of establishing the CHI-S in Uganda, a Stakeholders’ Meeting was held in Entebbe in 2017. Regulators, community members, researchers and policy-makers discussed implementation challenges and recommended preparatory steps: risk assessment; development of infrastructure and technical capacity to produce the infectious challenge material in Uganda; community engagement from Parliamentary to grass-roots level; pilot studies to establish approaches to assuring fully informed consent and true voluntariness, and strategies for selection of volunteers who can avoid natural infection during the 12-week CHI-S; the building of regulatory capacity; and the development of study protocols and a product dossier in close consultation with ethical and regulatory partners. It was recommended that, on completion, the protocol and product dossier be reviewed for approval in a joint meeting combining ethical, regulatory and environment management authorities. Most importantly, representatives of schistosomiasis-affected communities emphasised the urgent need for an effective vaccine and urged the research community not to delay in the development process.
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    Genetic diversity of Ascaris in southwestern Uganda
    (Transactions of the Royal Society of Tropical Medicine and Hygiene, 2012) Betson, Martha; Nejsum, Peter; Llewellyn-Hughes, Julia; Griffin, Claire; Atuhaire, Aaron; Arinaitwe, Moses; Adriko, Moses; Ruggiana, Andrew; Turyakira, Grace; Kabatereine, Narcis B.; Stothard, Russell
    Despite the common occurrence of ascariasis in southwestern Uganda, helminth control in the region has been limited. To gain further insights into the genetic diversity of Ascaris in this area, a parasitological survey in mothers (n = 41) and children (n = 74) living in two villages, Habutobere and Musezero, was carried out. Adult Ascaris worms were collected from infected individuals by chemo-expulsion using pyrantel pamoate treatment. Genetic diversity within these worms was assessed by inspection of DNA sequence variation in a mitochondrial marker and length polymorphism at microsatellite loci. Overall prevalence of ascariasis was 42.5% in mothers and 30.4% in their children and a total of 98 worms was examined from 18 hosts. Sequence analysis of a portion of the mitochondrial cytochrome c oxidase subunit 1 gene revealed 19 different haplotypes, 13 of which had not been previously encountered. Microsatellite analysis using eight loci provided evidence for high gene flow between worm populations from the two villages but comparing these worms with others obtained in a prior study on Unguja, Zanzibar, confirmed little genetic exchange and mixing of worm populations between the two areas. By adding to our understanding of the genetic diversity of Ascaris in Africa, this study provides useful information for monitoring changes in parasite population structure in the face of ongoing and future control.
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    Risk Assessment for the Implementation of Controlled Human Schistosoma Mansoni Infection Trials in Uganda
    (AAS open research, 2019) Koopman, Jan Pieter; Egesa, Moses; Wajja, Anne; Adriko, Moses; Nassuuna, Jacent; Nkurunungi, Gyaviira; Driciru, Emmanuella; Cose, Stephen; Kaleebu, Pontiano; Kabatereine, Narcis; Tukahebwa, Edridah; Elliott, Alison M.
    Schistosomiasis is a parasitic infection highly prevalent in sub-Saharan Africa, and a significant cause of morbidity; it is a priority for vaccine development. A controlled human infection model for Schistosoma mansoni (CHI-S) with potential to accelerate vaccine development has been developed among naïve volunteers in the Netherlands. Because responses both to infections and candidate vaccines are likely to differ between endemic and non-endemic settings, we propose to establish a CHI-S in Uganda where Schistosoma mansoni is endemic. As part of a “road-map” to this goal, we have undertaken a risk assessment. We identified risks related to importing of laboratory vector snails and schistosome strains from the Netherlands to Uganda; exposure to natural infection in endemic settings concurrently with CHI-S studies, and unfamiliarity of the community with the nature, risks and rationale for CHI. Mitigating strategies are proposed. With careful implementation of the latter, we believe that CHI-S can be implemented safely in Uganda. Our reflections are presented here to promote feedback and discussion.