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Assessing antigenic drift and phylogeny of influenza A (H1N1) pdm09 virus in Kenya using HA1 sub-unit of the hemagglutinin gene.
No full textInfluenza A (H1N1) pdm09 virus emerged in North America in 2009 and has been established as a seasonal strain in humans. After an antigenic stasis of about six years, new antigenically distinct variants of the virus emerged globally in 2016 necessitating a change in the vaccine formulation for the first time in 2017. Herein, we analyzed thirty-eight HA sequences of influenza A (H1N1) pdm09 strains isolated in Kenya during 2015-2018 seasons, to evaluate their antigenic and molecular properties based on the HA1 sub-unit. Our analyses revealed that the A (H1N1) pdm09 strains that circulated in Kenya during this period belonged to genetic clade 6B, subclade 6B.1 and 6B.2. The Kenyan 2015 and 2016 isolates differed from the vaccine strain A/California/07/2009 at nine and fourteen antigenic sites in the HA1 respectively. Further, those isolated in 2017 and 2018 correspondingly varied from A/Michigan/45/2015 vaccine strain at three and fifteen antigenic sites. The predicted vaccine efficacy of A/California/07/2009 against Kenyan 2015/2016 was estimated to be 32.4% while A/Michigan/45/2015 showed estimated vaccine efficacies of 39.6% - 41.8% and 32.4% - 42.1% against Kenyan 2017 and 2018 strains, respectively. Hemagglutination-inhibition (HAI) assay using ferret post-infection reference antiserum showed that the titers for the Kenyan 2015/2016 isolates were 2-8-fold lower compared to the vaccine strain. Overall, our results suggest the A (H1N1) pdm09 viruses that circulated in Kenya during 2015/2016 influenza seasons were antigenic variants of the recommended vaccine strains, denoting sub-optimal vaccine efficacy. Additionally, data generated point to a swiftly evolving influenza A (H1N1) pdm09 virus in recent post pandemic era, underscoring the need for sustained surveillance coupled with molecular and antigenic analyses, to inform appropriate and timely influenza vaccine update
Bioprospecting Staphylococcus Phages with Therapeutic and Bio-Control Potential.
No full textEmergence of antibiotic-resistant bacteria is a serious threat to the public health. This is also true for Staphylococcus aureus and other staphylococci. Staphylococcus phages Stab20, Stab21, Stab22, and Stab23, were isolated in Albania. Based on genomic and phylogenetic analysis, they were classified to genus Kayvirus of the subfamily Twortvirinae. In this work, we describe the in-depth characterization of the phages that electron microscopy confirmed to be myoviruses. These phages showed tolerance to pH range of 5.4 to 9.4, to maximum UV radiation energy of 25 µJ/cm2, to temperatures up to 45 °C, and to ethanol concentrations up to 25%, and complete resistance to chloroform. The adsorption rate constants of the phages ranged between 1.0 × 10-9 mL/min and 4.7 × 10-9 mL/min, and the burst size was from 42 to 130 plaque-forming units. The phages Stab20, 21, 22, and 23, originally isolated using Staphylococcus xylosus as a host, demonstrated varied host ranges among different Staphylococcus strains suggesting that they could be included in cocktail formulations for therapeutic or bio-control purpose. Phage particle proteomes, consisting on average of ca 60-70 gene products, revealed, in addition to straight-forward structural proteins, also the presence of enzymes such DNA polymerase, helicases, recombinases, exonucleases, and RNA ligase polymer. They are likely to be injected into the bacteria along with the genomic DNA to take over the host metabolism as soon as possible after infection
Use of the Consolidated Framework for Implementation Research (CFIR) to Characterize Healthcare Workers' Perspectives on Financial Incentives to Increase Pediatric HIV Testing.
No full textBACKGROUND:
A prior randomized control trial showed financial incentives increase HIV testing rates for children of unknown HIV status. Translating evidence-based interventions such as these to scale requires an implementation science approach.
METHODS:
A qualitative study evaluating healthcare providers' perceptions of barriers and facilitators of a previously completed financial incentives intervention for pediatric HIV testing was conducted at healthcare facilities in Kisumu, Kenya. Six focus group discussions with 52 providers explored determinants of acceptability, feasibility and sustainability of financial incentive scale-up for pediatric HIV testing using the Consolidated Framework for Implementation Research to inform question guides and thematic analysis.
RESULTS:
Providers found the use of financial incentive interventions for pediatric HIV testing to be highly acceptable. First, providers believed financial incentives had a relative advantage over existing strategies because they overcame cost barriers and provided additional motivation to test; however, concerns about how financial incentives would be implemented influenced perceptions of feasibility and sustainability. Secondly, providers expressed concern that already overburdened staff and high costs of financial incentive programs would limit sustainability. Thirdly, providers feared that financial incentives might negatively affect further care due to expectations of repeated financial support and program manipulation.
CONCLUSION:
Providers viewed financial incentives as an acceptable intervention to scale programmatically to increase uptake of pediatric testing. To ensure feasibility and sustainability of financial incentives in pediatric HIV testing programs, it will be important to clearly define target populations, manage expectations of continued financial support, and establish systems to track testing
Teaching Canadian Literature in the University of Nairobi
No full textThis paper discusses experiences of teaching Canadian literature in the Department of Literature, University of Nairobi, Kenya. For a long time, the University of Nairobi syllabus required that teaching Canadian literature, or any foreign literature for that matter, should be related to an African experience. This paper explores a few possible but unworkable ways on how one could relate teaching Canadian literature to an African experience as a way of establishing its relationship to students in Nairobi, Kenya, which is over 10 000 kilometres away from Canada. On the whole, the paper argues that an effective approach to teaching the literature has been formalist that takes into account fidelity to the nature and function of literature, even as it reveals the universal in the particular that makes the form and content of Canadian literature relevant to Kenyan as well as to African experiences. In the end, the paper points out the past experience of teaching and learning Canadian literature must have been valuable to both student and teacher as two seminars held outside the university demonstrate that Kenyans can relate to it for — after all — literature is universal in the particular
