School-wide publications

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Start date: 1991

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Now showing 1 - 10 of 160
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    Whole-genome sequencing and phylogenetic analysis of the first and second confirmed cases of human infection with Monkeypox virus from Sierra Leone
    (Elsevier BV, 2025-08-12) Yu, Shuo
    Whole-genome sequencing and phylogenetic analysis of the first and second confirmed cases of human infection with Monkeypox virus from Sierra LeoneTo the Editor, We read with great interest the letter by Yadav and colleagues, which detailed the need to focus on understanding the evolutionary trajectory of monkeypox virus. 1 The monkeypox virus (MPXV) is genetically classified into four primary clades (Ia, Ib, IIa, IIb).Notably, the newly identified clade Ib has emerged as the dominant strain in the current Public Health Emergency of International Concern (PHEIC), exemplified by the ongoing outbreak in the Democratic Republic of the Congo. 2 Concurrently, global transmission of clade IIb MPXV persists, underscoring that the ongoing epidemic warrants serious attention.On January 10-11, 2025, Sierra Leone released the case reports of its first two human infections with monkeypox virus during the PHEIC, becoming the final member of the Mano River Alliance to document such cases.Here, we present the two case studies with viral sequencing insights, shedding light on MPXV evolution in West Africa.Case 1 was a male in his twenties working as a car dealer who presented to the hospital in early January.He had traveled to Lungi (Port Loko District) from 26 December 2024 to 5 January 2025 (Fig. 1A).Symptom onset occurred on 6 January.Case 2, a male staff at a restaurant over 20 years old, developed symptoms on 6 January and sought hospital care in January.Both of the vesicle samples were confirmed MPXV-positive by real-time PCR using Monkeypox Virus Nucleic Acid Detection Kit at the Molecular Laboratory of 34th Military Hospital in Sierra Leone on January 10 and 11, respectively (Fig. 1A; Fig. S1 in the Appendix).Mean cycle threshold values were 20.29 for Case 1 and 15.14 for Case 2. The patients were admitted to the infectious disease isolation unit and were managed appropriately.Pre-rash symptoms included fever and headache, with rash involvement of the face, palms, and other cutaneous sites (Fig. S2 in the Appendix).Case 2 additionally presented with genital rashes with dysuria.Both patients denied animal/known case exposure, blood transfusions, travel (except for Case 1's documented trip, Journal of Infection 91 (2025) 106587
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    The relationship between decrease in feed intake and infection with trypanosoma congolense and T. vivax in West African dwarf goats
    (Taylor & Francis, 1993-03-01) Wassink, G. J.
    Twenty-three mature dwarf goats were used to study whether there is a relationship between the decrease in feed intake for individual goats and infection with T.congolense and T. vivax. Furthermore, it was investigated how rectal temperatures and blood parameters were affected by the T. congolense infection and how changes in these parameters can be used to predict the effect of a T. vivax infection on feed intake. For individual goats a ranking correlation was found between relative dry matter intake and infection (r = 0.59; p < .05). Animals with the most marked decrease in dry matter intake during the T. congolense infection showed a smaller increase in urea and a higher increase in non esterified fatty acids and beta-hydroxy butyrate levels in their blood. Evidence was obtained that the relative decrease in dry matter intake for individual goats during a T. vivax infection can be predicted on the basis of urea and creatinine responses measured in the blood during a previous infection with T. congolense infection.
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    Inland valley swamp rice development: Malaria, schistosomiasis, onchocerciasis in South Central Sierra Leone
    (Elsevier BV, 1994-03-01) Gbakima, A A
    The prevalence of malaria, schistosomiasis and onchocerciasis was determined in 1,106 residents of five villages in the Moyamba District, Southern Sierra Leone, to determine whether inland valley swamp (IVS) development was associated with changes in the prevalence of malaria, schistosomiasis and onchocerciasis in these villages. These parasitic diseases were studied in four villages receiving IVS, Food and Agricultural Organization (FAO) assistance and in one village not receiving FAO assistance. Malaria was the most prevalent infection, detected in 42.6% of the persons examined, followed by O. volvulus (17.7%), S. haematobium (0.6%) and S. mansoni (0.3%). Plasmodium falciparum accounted for 90.4% of the malaria infections, followed by P. malaria (2.1%), P. ovale (0.5%), and mixed infections (7.0%). The trend of infection to O. volvulus increased significantly with an increase in age. S. haematobium (0.6%) and S. mansoni (0.3%) infections were low and no Biomphalaria pfeifferi and Bulinus globosus were found in 33 IVS development swamps examined. These data indicate that IVS development is associated with an increase in the prevalence of malaria infection, but not in the prevalence of O. volvulus, S. haematobium and S. mansoni.
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    Functionality and Antioxidant Properties of Tilapia (Oreochromis niloticus) as Influenced by the Degree of Hydrolysis
    (Multidisciplinary Digital Publishing Institute, 2010-04-26) Foh, Mohamed Beva Kelfala
    Freeze dried protein powders (Fresh minced meat, FMM and Hot water dip, HWD) from tilapia (Oreochromis niloticus) were hydrolyzed by Alcalase 2.4 L (Alc), Flavourzyme (Flav) and Neutrase (Neut), and investigated for antioxidant activity and their functional properties. FMM and HWD hydrolysed by Alc, exhibiting superior antioxidant activity, had estimated degrees of hydrolysis (DH) of 23.40% and 25.43%, respectively. The maximum values of the 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS), 3-(2-pyridyl) 5,6-bis(4-phenyl-sulphonic acid)-1,2,4-triazine (ferrozine), radical scavenging activities and metal chelating properties were 86.67%, 91.27% and 82.57%, and 84.67%, 92.60% and 78.00% for FMM and HWD, respectively, with a significant difference (P 8,000 Da. At pH 2, FMM and HWD hydrolysates have varying solubilities above 85% (Alc FMM; 91.33%, Flav FMM; 79.5%, Neut FMM; 83.8% and Alc HWD; 90.45%, Flav HWD; 83.5%, and Neut HWD; 85.8%). They have 'U' shaped solubility curves, water holding capacity was in the range of 2.77 and 1.77 mL/g, while oil holding capacity ranged between 3.13 and 2.23 mL/g. FMM and HWD have the highest bulk density of 0.53 and 0.53 for Neutrase and Alcalase 2.4 L, respectively. Foam capacity and stability ranged from 125.5 to 61.4, 138.5 to 45.2, 130.0 to 62.5, and 124.5 to 55.0, 137.5 to 53.3, 129.6 to 62.7 for FMM and HWD hydrolyzed with Alcalase 2.4 L, Flavourzyme and Neutrase, respectively. Tilapia fish protein hydrolysates are thus potential functional food ingredients.
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    Improved mapping strategy to better inform policy on the control of schistosomiasis and soil-transmitted helminthiasis in Sierra Leone
    (BioMed Central, 2011-06-06) Hodges, Mary
    BACKGROUND: Schistosomiasis and soil-transmitted helminthiasis (STH) are endemic in Sierra Leone confirmed by national mapping in 2008. To better inform planning of preventive chemotherapy strategy, another survey was conducted before mass drug administration (MDA) in seven districts according to the mapping results or local knowledge. Fifty-nine chiefdoms and one school in every chiefdom were selected. Thirty school children aged 9-14 years from each school (total: 1760) were examined by parasitological methods for infection with Schistosoma mansoni and STHs. RESULTS: The overall prevalence of S. mansoni was 40.2% (95% confidence interval (CI): 37.9-42.5%), particularly in Kailahun (63.3%), Kenema (46.7%), Koinadugu (41.9%) and Kono (71.7%). The results demonstrated the focal distribution of S. mansoni in Bo, Tonkolili and Bombali districts with prevalence ranging from 0.0-63.3%, 3.3-90.0% and 0.0-67.9% respectively. The arithmetic mean intensity of S. mansoni infection was 95.4 epg (95% CI: 61.4-129.5 epg), Heavy mean intensity of infection was found in Kailahun (120.2 epg), Kenema (104.5 epg), Koinadugu (112.3 epg) and Kono (250.3 epg). Heavy or moderate infection with S. mansoni occurred in 20.7% of children examined. Hookworm prevalence was moderate: 31.2% (95% CI: 29.1-33.4%), but high in Bo (50.0%) and Tonkolili (56.7%). Hookworm intensity of infection was light with a mean epg of 53.0 (95% CI: 38.4-67.7 epg). Prevalence and intensity of Ascaris lumbricoides (1.5%, 17.8 epg) and Trichuris trichiura (2.5%, 20.3 epg) was low. CONCLUSIONS: The prediction by previous spatial analysis that S. mansoni was highly endemic across north-eastern Sierra Leone was confirmed with a significant proportion of children heavily or moderately infected. The distribution of S. mansoni in Bo, Tonkolili and Bombali districts ranged widely, highlighting the importance of considering the nature of focal transmission in national mapping exercises. These results were used to refine the MDA for schistosomiasis control to chiefdom implementation units rather than the entire district in these 3 districts. The survey demonstrated that sufficient number of survey sites for schistosomiasis mapping in each district should be used to provide a better national planning of MDA activities, and that it is affordable with the contributions from all parties involved and national resources mobilized.
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    Mass drug administration significantly reduces infection of Schistosoma mansoni and hookworm in school children in the national control program in Sierra Leone
    (BioMed Central, 2012-01-22) Hodges, Mary H
    BACKGROUND: The first-ever round of school-based mass drug administration (MDA) with praziquantel together with mebendazole targeting school-aged children in endemic districts was conducted in 2009 by the National Neglected Tropical Diseases Control Program. To evaluate the impact of the treatment regimen, a cross-sectional sentinel site survey was conducted 6 months post-MDA. METHODS: Fifteen sentinel schools from six highly endemic districts (according to data from national and pre-MDA surveys) with Schistosoma mansoni affecting over 50% of the population, and moderate to high prevalence of hookworms (> 20%). Approximately 30 children aged 9-14 years were selected from each school and stool samples (one per student) were examined by the Kato-Katz method. RESULTS: The overall prevalence (and intensity) in these sentinel sites pre-MDA of S. mansoni was 69.0% (170.8 epg), hookworm: 41.7% (71.7 epg), Ascaris lumbricoides: 1.8% and Trichuris trichiura: 3.8%. Six months post MDA, the findings were S. mansoni: 38.2% (47.3 epg) and hookworm: 14.5% (8.7 epg), representing a reduction from pre-MDA levels of 44.6% (65.2%) and 72.3% (87.9%) respectively. The proportion of children who were moderately or heavily infected with S. mansoni fell from 35.6% pre MDA to 9.9% post MDA. CONCLUSIONS: Significant reduction in S. mansoni and hookworm infection was achieved by this first round MDA in school-going children in Sierra Leone. This reduction in infection burden can potentially contribute to a reduction of morbidity, such as anaemia, in these children.
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    Reemergence of Chikungunya Virus in Bo, Sierra Leone
    (Centers for Disease Control and Prevention, 2013-05-24) Ansumana, Rashid
    We diagnosed 400 possible IgM-positive cases of chikungunya virus in Bo, Sierra Leone, during July 2012-January 2013 by using lateral flow immunoassays. Cases detected likely represent only a small fraction of total cases. Further laboratory testing is required to confirm this outbreak and characterize the virus.
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