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Walker R, Fothergill-Misbah N, Kariuki S, Ojo O, Cilia R, Dekker MCJ, Agabi O, Akpalu A, Amod F, Breckons M, Cham M, Del Din S, Dotchin C, Guggsa S, Kwasa J, Mushi D, Nwaokorie FO, Park T, Rochester L, Rogathi J, Sarfo FS, Shalash A, Ternent L, Urasa S, Okubadejo N. Transforming Parkinson's Care in Africa (TraPCAf): protocol for a multimethodology National Institute for Health and Care Research Global Health Research Group project. BMC Neurol 2023; 23:373. [PMID: 37858118 PMCID: PMC10585779 DOI: 10.1186/s12883-023-03414-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Accepted: 09/29/2023] [Indexed: 10/21/2023] Open
Abstract
BACKGROUND Parkinson's disease (PD) is the second most common neurodegenerative disorder and, according to the Global Burden of Disease estimates in 2015, was the fastest growing neurological disorder globally with respect to associated prevalence, disability, and deaths. Information regarding the awareness, diagnosis, phenotypic characteristics, epidemiology, prevalence, risk factors, treatment, economic impact and lived experiences of people with PD from the African perspective is relatively sparse in contrast to the developed world, and much remains to be learned from, and about, the continent. METHODS Transforming Parkinson's Care in Africa (TraPCAf) is a multi-faceted, mixed-methods, multi-national research grant. The study design includes multiple sub-studies, combining observational (qualitative and quantitative) approaches for the epidemiological, clinical, risk factor and lived experience components, as appropriate, and interventional methods (clinical trial component). The aim of TraPCAf is to describe and gain a better understanding of the current situation of PD in Africa. The countries included in this National Institute for Health and Care Research (NIHR) Global Health Research Group (Egypt, Ethiopia, Ghana, Kenya, Nigeria, South Africa and Tanzania) represent diverse African geographies and genetic profiles, with differing resources, healthcare systems, health and social protection schemes, and policies. The research team is composed of experts in the field with vast experience in PD, jointly led by a UK-based and Africa-based investigator. DISCUSSION Despite the increasing prevalence of PD globally, robust data on the disease from Africa are lacking. Existing data point towards the poor awareness of PD and other neurological disorders on the continent and subsequent challenges with stigma, and limited access to affordable services and medication. This multi-site study will be the first of its kind in Africa. The data collected across the proposed sub-studies will provide novel and conclusive insights into the situation of PD. The selected country sites will allow for useful comparisons and make results relevant to other low- and middle-income countries. This grant is timely, as global recognition of PD and the public health challenge it poses builds. The work will contribute to broader initiatives, including the World Health Organization's Intersectoral global action plan on epilepsy and other neurological disorders. TRIAL REGISTRATION https://doi.org/10.1186/ISRCTN77014546 .
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Affiliation(s)
- R Walker
- Northumbria Healthcare NHS Foundation Trust, Newcastle upon Tyne, UK
- Population Health Sciences Institute, Newcastle University, Newcastle upon Tyne, UK
| | - N Fothergill-Misbah
- Population Health Sciences Institute, Newcastle University, Newcastle upon Tyne, UK.
| | - S Kariuki
- Neuroscience Unit, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - O Ojo
- College of Medicine, University of Lagos, Lagos, Nigeria
- Lagos University Teaching Hospital, Lagos, Nigeria
| | - R Cilia
- Parkinson and Movement Disorders Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - M C J Dekker
- Kilimanjaro Christian Medical Centre, Moshi, Tanzania
- Kilimanjaro Christian Medical University College, Moshi, Tanzania
| | - O Agabi
- College of Medicine, University of Lagos, Lagos, Nigeria
| | - A Akpalu
- University of Ghana Medical School, Korle Bu Teaching Hospital, Accra, Ghana
| | - F Amod
- University of KwaZulu-Natal, Durban, South Africa
| | - M Breckons
- Population Health Sciences Institute, Newcastle University, Newcastle upon Tyne, UK
| | - M Cham
- Richard Novati Catholic Hospital, Sogakope, Ghana
| | - S Del Din
- Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK
- National Institute for Health and Care Research (NIHR) Newcastle Biomedical Research Centre (BRC), Newcastle University and Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
| | - C Dotchin
- Northumbria Healthcare NHS Foundation Trust, Newcastle upon Tyne, UK
- Population Health Sciences Institute, Newcastle University, Newcastle upon Tyne, UK
| | - S Guggsa
- Addis Ababa University, Addis Ababa, Ethiopia
| | - J Kwasa
- Department of Clinical Medicine and Therapeutics, University of Nairobi, Nairobi, Kenya
| | - D Mushi
- Institute of Public Health, Kilimanjaro Christian Medical University College, Moshi, Tanzania
| | - F O Nwaokorie
- Department of Medical Laboratory Science, Faculty of Basic Medical Sciences, College of Medicine, University of Lagos, Lagos, Nigeria
| | - T Park
- Parkinson's Africa, Kingston upon Thames, UK
| | - L Rochester
- Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK
- National Institute for Health and Care Research (NIHR) Newcastle Biomedical Research Centre (BRC), Newcastle University and Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
| | - J Rogathi
- Kilimanjaro Christian Medical Centre, Moshi, Tanzania
- Kilimanjaro Christian Medical University College, Moshi, Tanzania
| | - F S Sarfo
- Kwame Nkrumah University of Science & Technology, Kumasi, Ghana
| | - A Shalash
- Department of Neurology, Faculty of Medicine, Ain Shams University, Cairo, Egypt
| | - L Ternent
- Population Health Sciences Institute, Newcastle University, Newcastle upon Tyne, UK
| | - S Urasa
- Kilimanjaro Christian Medical Centre, Moshi, Tanzania
- Kilimanjaro Christian Medical University College, Moshi, Tanzania
| | - N Okubadejo
- College of Medicine, University of Lagos, Lagos, Nigeria
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Hassell JM, Muloi DM, VanderWaal KL, Ward MJ, Bettridge J, Gitahi N, Ouko T, Imboma T, Akoko J, Karani M, Muinde P, Nakamura Y, Alumasa L, Furmaga E, Kaitho T, Amanya F, Ogendo A, Fava F, Wee BA, Phan H, Kiiru J, Kang’ethe E, Kariuki S, Robinson T, Begon M, Woolhouse MEJ, Fèvre EM. Epidemiological connectivity between humans and animals across an urban landscape. Proc Natl Acad Sci U S A 2023; 120:e2218860120. [PMID: 37450494 PMCID: PMC10629570 DOI: 10.1073/pnas.2218860120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Accepted: 05/19/2023] [Indexed: 07/18/2023] Open
Abstract
Urbanization is predicted to be a key driver of disease emergence through human exposure to novel, animal-borne pathogens. However, while we suspect that urban landscapes are primed to expose people to novel animal-borne diseases, evidence for the mechanisms by which this occurs is lacking. To address this, we studied how bacterial genes are shared between wild animals, livestock, and humans (n = 1,428) across Nairobi, Kenya-one of the world's most rapidly developing cities. Applying a multilayer network framework, we show that low biodiversity (of both natural habitat and vertebrate wildlife communities), coupled with livestock management practices and more densely populated urban environments, promotes sharing of Escherichia coli-borne bacterial mobile genetic elements between animals and humans. These results provide empirical support for hypotheses linking resource provision, the biological simplification of urban landscapes, and human and livestock demography to urban dynamics of cross-species pathogen transmission at a landscape scale. Urban areas where high densities of people and livestock live in close association with synanthropes (species such as rodents that are more competent reservoirs for zoonotic pathogens) should be prioritized for disease surveillance and control.
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Affiliation(s)
- James M. Hassell
- Global Health Program, Smithsonian’s National Zoo and Conservation Biology Institute, Washington, DC20008
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, CT06510
- Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, LiverpoolL69 3BX, United Kingdom
| | - Dishon M. Muloi
- Usher Institute, University of Edinburgh, EdinburghEH16 4SS, United Kingdom
- International Livestock Research Institute, 00100Nairobi, Kenya
- Centre for Immunity, Infection and Evolution, University of Edinburgh, EdinburghEH9 3FL, United Kingdom
| | - Kimberly L. VanderWaal
- Department of Veterinary Population Medicine, College of Veterinary Medicine, University of Minnesota, St. Paul, MN55108
| | - Melissa J. Ward
- Usher Institute, University of Edinburgh, EdinburghEH16 4SS, United Kingdom
- Nuffield Department of Clinical Medicine, University of Oxford, OxfordOX3 7BN, United Kingdom
- Faculty of Medicine, University of Southampton, SouthamtonSO17 1BJ, United Kingdom
| | - Judy Bettridge
- Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, LiverpoolL69 3BX, United Kingdom
- International Livestock Research Institute, 00100Nairobi, Kenya
| | | | - Tom Ouko
- Kenya Medical Research Institute, 00200Nairobi, Kenya
| | | | - James Akoko
- International Livestock Research Institute, 00100Nairobi, Kenya
| | - Maurice Karani
- International Livestock Research Institute, 00100Nairobi, Kenya
| | - Patrick Muinde
- International Livestock Research Institute, 00100Nairobi, Kenya
| | - Yukiko Nakamura
- Faculty of Veterinary Medicine, Hokkaido University, Sapporo060-0818, Japan
| | - Lorren Alumasa
- International Livestock Research Institute, 00100Nairobi, Kenya
| | - Erin Furmaga
- Department of Epidemiology, Columbia University, New York, NY10032
| | - Titus Kaitho
- Veterinary Services Department, Kenya Wildlife Service, 00100Nairobi, Kenya
| | - Fredrick Amanya
- International Livestock Research Institute, 00100Nairobi, Kenya
| | - Allan Ogendo
- International Livestock Research Institute, 00100Nairobi, Kenya
| | - Francesco Fava
- International Livestock Research Institute, 00100Nairobi, Kenya
- Department of Environmental Science and Policy, Università degli Studi di Milano, 20133Milan, Italy
| | - Bryan A. Wee
- Usher Institute, University of Edinburgh, EdinburghEH16 4SS, United Kingdom
| | - Hang Phan
- Nuffield Department of Clinical Medicine, University of Oxford, OxfordOX3 7BN, United Kingdom
| | - John Kiiru
- Kenya Medical Research Institute, 00200Nairobi, Kenya
| | | | - Sam Kariuki
- Kenya Medical Research Institute, 00200Nairobi, Kenya
| | - Timothy Robinson
- Food and Agriculture Organization of the United Nations, 00153Rome, Italy
| | - Michael Begon
- Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, LiverpoolL69 3BX, United Kingdom
| | - Mark E. J. Woolhouse
- Usher Institute, University of Edinburgh, EdinburghEH16 4SS, United Kingdom
- Centre for Immunity, Infection and Evolution, University of Edinburgh, EdinburghEH9 3FL, United Kingdom
| | - Eric M. Fèvre
- Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, LiverpoolL69 3BX, United Kingdom
- International Livestock Research Institute, 00100Nairobi, Kenya
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Miller KM, Tanz RR, Shulman ST, Carapetis JR, Cherian T, Lamagni T, Bowen AC, Pickering J, Fulurija A, Moore HC, Cannon JW, Barnett TC, Van Beneden CA, Carapetis J, Van Beneden C, Kaslow DC, Cherian T, Lamagni T, Engel M, Cannon J, Moore HC, Bowen A, Seale A, Kang G, Watkins D, Kariuki S. Standardization of Epidemiological Surveillance of Group A Streptococcal Pharyngitis. Open Forum Infect Dis 2022; 9:S5-S14. [PMID: 36128410 PMCID: PMC9474939 DOI: 10.1093/ofid/ofac251] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Pharyngitis, more commonly known as sore throat, is caused by viral and/or bacterial infections. Group A Streptococcus (Strep A) is the most common bacterial cause of pharyngitis. Strep A pharyngitis is an acute, self-limiting disease but if undertreated can lead to suppurative complications, nonsuppurative poststreptococcal immune-mediated diseases, and toxigenic presentations. We present a standardized surveillance protocol, including case definitions for pharyngitis and Strep A pharyngitis, as well as case classifications that can be used to differentiate between suspected, probable, and confirmed cases. We discuss the current tests used to detect Strep A among persons with pharyngitis, including throat culture and point-of-care tests. The type of surveillance methodology depends on the resources available and the objectives of surveillance. Active surveillance and laboratory confirmation is the preferred method for case detection. Participant eligibility, the surveillance population and additional considerations for surveillance of pharyngitis are addressed, including baseline sampling, community engagement, frequency of screening and season. Finally, we discuss the core elements of case report forms for pharyngitis and provide guidance for the recording of severity and pain associated with the course of an episode.
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Affiliation(s)
- Kate M Miller
- Wesfarmers Centre for Vaccines and Infectious Diseases, Telethon Kids Institute, University of Western Australia , Perth , Australia
| | - Robert R Tanz
- Northwestern University Feinberg School of Medicine and Ann and Robert H. Lurie Children’s Hospital of Chicago , Chicago, Illinois , USA
| | - Stanford T Shulman
- Northwestern University Feinberg School of Medicine and Ann and Robert H. Lurie Children’s Hospital of Chicago , Chicago, Illinois , USA
| | - Jonathan R Carapetis
- Wesfarmers Centre for Vaccines and Infectious Diseases, Telethon Kids Institute, University of Western Australia , Perth , Australia
- Perth Children’s Hospital , Perth , Australia
| | | | - Theresa Lamagni
- United Kingdom Health Security Agency , London , United Kingdom
| | - Asha C Bowen
- Wesfarmers Centre for Vaccines and Infectious Diseases, Telethon Kids Institute, University of Western Australia , Perth , Australia
- Perth Children’s Hospital , Perth , Australia
| | - Janessa Pickering
- Wesfarmers Centre for Vaccines and Infectious Diseases, Telethon Kids Institute, University of Western Australia , Perth , Australia
| | - Alma Fulurija
- Wesfarmers Centre for Vaccines and Infectious Diseases, Telethon Kids Institute, University of Western Australia , Perth , Australia
| | - Hannah C Moore
- Wesfarmers Centre for Vaccines and Infectious Diseases, Telethon Kids Institute, University of Western Australia , Perth , Australia
| | - Jeffrey W Cannon
- Wesfarmers Centre for Vaccines and Infectious Diseases, Telethon Kids Institute, University of Western Australia , Perth , Australia
- Department of Global Health and Population, Harvard T. H. Chan School of Public Health , Boston, Massachusetts , USA
| | - Timothy C Barnett
- Wesfarmers Centre for Vaccines and Infectious Diseases, Telethon Kids Institute, University of Western Australia , Perth , Australia
| | - Chris A Van Beneden
- CDC Foundation, Centers for Disease Control and Prevention , Atlanta, Georgia , USA
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4
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Miller KM, Carapetis JR, Cherian T, Hay R, Marks M, Pickering J, Cannon JW, Lamagni T, Romani L, Moore HC, Van Beneden CA, Barth DD, Bowen AC, Carapetis J, Van Beneden C, Kaslow D, Cherian T, Lamagni T, Engel M, Cannon J, Moore H, Bowen A, Seale A, Kang G, Watkins D, Kariuki S. Standardization of Epidemiological Surveillance of Group A Streptococcal Impetigo. Open Forum Infect Dis 2022; 9:S15-S24. [PMID: 36128409 PMCID: PMC9474945 DOI: 10.1093/ofid/ofac249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Impetigo is a highly contagious bacterial infection of the superficial layer of skin. Impetigo is caused by group A Streptococcus (Strep A) and Staphylococcus aureus, alone or in combination, with the former predominating in many tropical climates. Strep A impetigo occurs mainly in early childhood, and the burden varies worldwide. It is an acute, self-limited disease, but many children experience frequent recurrences that make it a chronic illness in some endemic settings. We present a standardized surveillance protocol including case definitions for impetigo including both active (purulent, crusted) and resolving (flat, dry) phases and discuss the current tests used to detect Strep A among persons with impetigo. Case classifications that can be applied are detailed, including differentiating between incident (new) and prevalent (existing) cases of Strep A impetigo. The type of surveillance methodology depends on the burden of impetigo in the community. Active surveillance and laboratory confirmation is the preferred method for case detection, particularly in endemic settings. Participant eligibility, surveillance population and additional considerations for surveillance of impetigo, including examination of lesions, use of photographs to document lesions, and staff training requirements (including cultural awareness), are addressed. Finally, the core elements of case report forms for impetigo are presented and guidance for recording the course and severity of impetigo provided.
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Affiliation(s)
- Kate M Miller
- Wesfarmers Centre for Vaccines and Infectious Diseases, Telethon Kids Institute, University of Western Australia , Perth, Western Australia , Australia
| | - Jonathan R Carapetis
- Wesfarmers Centre for Vaccines and Infectious Diseases, Telethon Kids Institute, University of Western Australia , Perth, Western Australia , Australia
- Perth Children’s Hospital , Perth, Western Australia , Australia
| | | | - Roderick Hay
- St John’s Institute of Dermatology, King’s College London , United Kingdom
| | - Michael Marks
- Clinical Research Department, Faculty of Infectious Diseases, London School of Hygiene and Tropical Medicine , London , United Kingdom
- Hospital for Tropical Diseases, University College , London , United Kingdom
- Division of Infection and Immunity, University College London , London , United Kingdom
| | - Janessa Pickering
- Wesfarmers Centre for Vaccines and Infectious Diseases, Telethon Kids Institute, University of Western Australia , Perth, Western Australia , Australia
| | - Jeffrey W Cannon
- Wesfarmers Centre for Vaccines and Infectious Diseases, Telethon Kids Institute, University of Western Australia , Perth, Western Australia , Australia
- Department of Global Health and Population, Harvard T. H. Chan School of Public Health , Boston, Massachusetts , USA
| | - Theresa Lamagni
- United Kingdom Health Security Agency , London , United Kingdom
| | - Lucia Romani
- The Kirby Institute, University of New South Wales Sydney , Sydney , Australia
- Murdoch Children’s Research Group , Melbourne , Australia
| | - Hannah C Moore
- Wesfarmers Centre for Vaccines and Infectious Diseases, Telethon Kids Institute, University of Western Australia , Perth, Western Australia , Australia
| | - Chris A Van Beneden
- CDC Foundation, Centers for Disease Control and Prevention , Atlanta, Georgia , USA
| | - Dylan D Barth
- Wesfarmers Centre for Vaccines and Infectious Diseases, Telethon Kids Institute, University of Western Australia , Perth, Western Australia , Australia
| | - Asha C Bowen
- Wesfarmers Centre for Vaccines and Infectious Diseases, Telethon Kids Institute, University of Western Australia , Perth, Western Australia , Australia
- Perth Children’s Hospital , Perth, Western Australia , Australia
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Wakeman BS, Shakamuri P, McDonald MA, Weinberg J, Svoboda P, Murphy MK, Kariuki S, Mace K, Elder E, Rivera H, Qvarnstrom Y, Pohl J, Shi YP. Development of a new peptide-bead coupling method for an all peptide-based Luminex multiplexing assay for detection of Plasmodium falciparum antibody responses. J Immunol Methods 2021; 499:113148. [PMID: 34560073 DOI: 10.1016/j.jim.2021.113148] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Revised: 08/16/2021] [Accepted: 09/15/2021] [Indexed: 11/16/2022]
Abstract
Using a recombinant protein antigen for antibody testing shows a sum of antibody responses to multiple different immune epitopes existing in the protein antigen. In contrast, the antibody testing to an immunogenic peptide epitope reflects a singular antibody response to the individual peptide epitope. Therefore, using a panel of peptide epitopes provides an advantage for profiling multiple singular antibody responses with potential to estimate recent malaria exposure in human infections. However, transitioning from malaria immune epitope peptide-based ELISA to an all peptide bead-based multiplex Luminex assay presents some challenges including variation in the ability of different peptides to bind beads. The aim of this study was to develop a peptide coupling method while demonstrating the utility of these peptide epitopes from multiple stage antigens of Plasmodium falciparum for measuring antibodies. Successful coupling of peptide epitopes to beads followed three steps: 1) development of a peptide tag appended to the C-terminus of each peptide epitope consisting of beta-alanine-lysine (x 4)--cysteine, 2) bead modification with a high concentration of adipic acid dihydrazide, and 3) use of the peptide epitope as a blocker in place of the traditional choice, bovine serum albumin (BSA). This new method was used to couple 12 peptide epitopes from multiple stage specific antigens of P. falciparum, 1 Anopheles mosquito salivary gland peptide, and 1 Epstein-Barr virus peptide as an assay control. The new method was applied to testing of IgG in pooled samples from 30 individuals with previously repeated malaria exposure in western Kenya and IgM and IgG in samples from 37 U.S. travelers with recent exposure to malaria. The new peptide-bead coupling method and subsequent multiplex Luminex assay showed reliable detection of IgG to all 14 peptides in Kenyan samples. Among 37 samples from U.S. travelers recently diagnosed with malaria, IgM and IgG to the peptide epitopes were detected with high sensitivity and variation. Overall, the U.S. travelers had a much lower positivity rates of IgM than IgG to different peptide epitopes, ranging from a high of 62.2% positive for one epitope to a low of only 5.4% positive for another epitope. In contrast, the travelers had IgG positive rates from 97.3% to 91.9% to various peptide epitopes. Based on the different distribution in IgM and IgG positivity to overall number of peptide epitopes and to the number of pre-erythrocytic, erythrocytic, gametocytic, and salivary stage epitopes at the individual level, four distinct patterns of IgM and IgG responses among the 37 samples from US travelers were observed. Independent peptide-bead coupling and antibody level readout between two different instruments also showed comparable results. Overall, this new coupling method resolves the peptide-bead coupling challenge, is reproducible, and can be applied to any other immunogenic peptide epitopes. The resulting all peptide bead-based multiplex Luminex assay can be expanded to include other peptide epitopes of P. falciparum, different malaria species, or other diseases for surveillance, either in US travelers or endemic areas.
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Affiliation(s)
- B S Wakeman
- Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, GA, USA.
| | - P Shakamuri
- Division of Scientific Resources, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA, USA.
| | - M A McDonald
- Division of Scientific Resources, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA, USA.
| | - J Weinberg
- Division of Scientific Resources, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA, USA.
| | - P Svoboda
- Division of Scientific Resources, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA, USA.
| | - M K Murphy
- Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, GA, USA.
| | - S Kariuki
- Kenya Medical Research Institute, Centre for Global Health Research, Kisumu, Kenya.
| | - K Mace
- Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, GA, USA.
| | - E Elder
- Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, GA, USA.
| | - H Rivera
- Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, GA, USA.
| | - Y Qvarnstrom
- Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, GA, USA.
| | - J Pohl
- Division of Scientific Resources, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA, USA.
| | - Y P Shi
- Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, GA, USA.
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6
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Oneko M, Cherop YR, Sang T, Gutman JR, Wiegand R, Nyang'au EM, Odila AD, Akach D, Hamel MJ, Samuels AM, Kariuki S, Abebe Y, Nzuu EL, Wijayalath W, James ER, Sim BKL, Billingsley PF, Richie TL, Hoffman SL, Seder RA, Steinhardt LC. Feasibility of direct venous inoculation of the radiation-attenuated Plasmodium falciparum whole sporozoite vaccine in children and infants in Siaya, western Kenya. Vaccine 2020; 38:4592-4600. [PMID: 32444192 DOI: 10.1016/j.vaccine.2020.05.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Revised: 04/30/2020] [Accepted: 05/04/2020] [Indexed: 10/24/2022]
Abstract
PfSPZ Vaccine, composed of radiation-attenuated, aseptic, purified, cryopreserved Plasmodium falciparum sporozoites, is administered by direct venous inoculation (DVI) for maximal efficacy against malaria. A critical issue for advancing vaccines that are administered intravenously is the ability to efficiently administer them across multiple age groups. As part of a pediatric safety, immunogenicity, and efficacy trial in western Kenya, we evaluated the feasibility and tolerability of DVI, including ease of venous access, injection time, and crying during the procedure across age groups. Part 1 was an age de-escalation, dose escalation trial in children aged 13 months-5 years and infants aged 5-12 months; part 2 was a vaccine efficacy trial including only infants, using the most skilled injectors from part 1. Injectors could use a vein viewer, if needed. A total of 1222 injections (target 0.5 mL) were initiated by DVI in 511 participants (36 were 5-9-year-olds, 65 were 13-59-month-olds, and 410 infants). The complete volume was injected in 1185/1222 (97.0%) vaccinations, 1083/1185 (91.4%) achieved with the first DVI. 474/511 (92.8%) participants received only complete injections, 27/511 (5.3%) received at least one partial injection (<0.5 mL), and in 10/511 (2.0%) venous access was not obtained. The rate of complete injections by single DVI for infants improved from 77.1% in part 1 to 92.8% in part 2. No crying occurred in 51/59 (86.4%) vaccinations in 5-9-year-olds, 25/86 (29.1%) vaccinations in 13-59-month-olds and 172/1067 (16.1%) vaccinations in infants. Mean administration time ranged from 2.6 to 4.6 minutes and was longer for younger age groups. These data show that vaccination by DVI was feasible and well tolerated in infants and children in this rural hospital in western Kenya, when performed by skilled injectors. We also report that shipping and storage in liquid nitrogen vapor phase was simple and efficient. (Clinicaltrials.gov NCT02687373).
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Affiliation(s)
- M Oneko
- Kenya Medical Research Institute, Centre for Global Health Research, Kisumu, Kenya.
| | - Y R Cherop
- Kenya Medical Research Institute, Centre for Global Health Research, Kisumu, Kenya
| | - T Sang
- Kenya Medical Research Institute, Centre for Global Health Research, Kisumu, Kenya
| | - J R Gutman
- Malaria Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - R Wiegand
- Malaria Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - E M Nyang'au
- Kenya Medical Research Institute, Centre for Global Health Research, Kisumu, Kenya
| | - A D Odila
- Kenya Medical Research Institute, Centre for Global Health Research, Kisumu, Kenya
| | - D Akach
- Kenya Medical Research Institute, Centre for Global Health Research, Kisumu, Kenya
| | - M J Hamel
- Malaria Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - A M Samuels
- Malaria Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - S Kariuki
- Kenya Medical Research Institute, Centre for Global Health Research, Kisumu, Kenya
| | - Y Abebe
- Sanaria Inc., Rockville, MD, USA
| | - E L Nzuu
- Kenya Medical Research Institute, Centre for Global Health Research, Kisumu, Kenya
| | | | | | | | | | | | | | - R A Seder
- National Institutes of Health, Bethesda, MD, USA
| | - L C Steinhardt
- Malaria Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, GA, USA
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7
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Muloi D, Ward M, Hassell J, Bettridge J, Robinson T, Pedersen A, Kang’ethe E, Kariuki S, Fèvre E, Woolhouse M. One Health genomic epidemiology of antimicrobial resistant Escherichia coli carriage in sympatric humans and livestock in Nairobi, Kenya. J Infect Public Health 2020. [DOI: 10.1016/j.jiph.2020.01.043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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8
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Hassell JM, Ward MJ, Muloi D, Bettridge JM, Robinson TP, Kariuki S, Ogendo A, Kiiru J, Imboma T, Kang'ethe EK, Öghren EM, Williams NJ, Begon M, Woolhouse MEJ, Fèvre EM. Clinically relevant antimicrobial resistance at the wildlife-livestock-human interface in Nairobi: an epidemiological study. Lancet Planet Health 2019; 3:e259-e269. [PMID: 31229001 PMCID: PMC6630895 DOI: 10.1016/s2542-5196(19)30083-x] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Revised: 04/25/2019] [Accepted: 04/26/2019] [Indexed: 05/17/2023]
Abstract
BACKGROUND Antimicrobial resistance is one of the great challenges facing global health security in the modern era. Wildlife, particularly those that use urban environments, are an important but understudied component of epidemiology of antimicrobial resistance. We investigated antimicrobial resistance overlap between sympatric wildlife, humans, livestock, and their shared environment across the developing city of Nairobi, Kenya. We use these data to examine the role of urban wildlife in the spread of clinically relevant antimicrobial resistance. METHODS 99 households across Nairobi were randomly selected on the basis of socioeconomic stratification. A detailed survey was administered to household occupants, and samples (n=2102) were collected from the faeces of 75 wildlife species inhabiting household compounds (ie, the household and its perimeter; n=849), 13 livestock species (n=656), and humans (n=333), and from the external environment (n=288). Escherichia coli, our sentinel organism, was cultured and a single isolate from each sample tested for sensitivity to 13 antibiotics. Diversity of antimicrobial resistant phenotypes was compared between urban wildlife, humans, livestock, and the environment, to investigate whether wildlife are a net source for antimicrobial resistance in Nairobi. Generalised linear mixed models were used to determine whether the prevalence of antimicrobial resistant phenotypes and multidrug-resistant E coli carriage in urban wildlife is linked to variation in ecological traits, such as foraging behaviour, and to determine household-level risk factors for sharing of antimicrobial resistance between humans, wildlife, and livestock. FINDINGS E coli were isolated from 485 samples collected from wildlife between Sept 6,2015, and Sept 28, 2016. Wildlife carried a low prevalence of E coli isolates susceptible to all antibiotics tested (45 [9%] of 485 samples) and a high prevalence of clinically relevant multidrug resistance (252 [52%] of 485 samples), which varied between taxa and by foraging traits. Multiple isolates were resistant to one agent from at least seven antimicrobial classes tested for, and a single isolate was resistant to all antibiotics tested for in the study. The phenotypic diversity of antimicrobial-resistant E coli in wildlife was lower than in livestock, humans, and the environment. Within household compounds, statistical models identified two interfaces for exchange of antimicrobial resistance: between both rodents, humans and their rubbish, and seed-eating birds, humans and their rubbish; and between seed-eating birds, cattle, and bovine manure. INTERPRETATION Urban wildlife carry a high burden of clinically relevant antimicrobial-resistant E coli in Nairobi, exhibiting resistance to drugs considered crucial for human medicine by WHO. Identifiable traits of the wildlife contribute to this exposure; however, compared with humans, livestock, and the environment, low phenotypic diversity in wildlife is consistent with the hypothesis that wildlife are a net sink rather than source of clinically relevant resistance. Wildlife that interact closely with humans, livestock, and both human and livestock waste within households, are exposed to more antimicrobial resistant phenotypes, and could therefore act as conduits for the dissemination of clinically relevant antimicrobial resistance to the wider environment. These results provide novel insight into the broader epidemiology of antimicrobial resistance in complex urban environments, characteristic of lower-middle-income countries. FUNDING UK Medical Research Council and CGIAR Research Program on Agriculture for Nutrition and Health.
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Affiliation(s)
- James M Hassell
- Institute of Infection and Global Health, University of Liverpool, Neston, UK; International Livestock Research Institute, Nairobi, Kenya
| | - Melissa J Ward
- Centre for Immunity, Infection and Evolution, University of Edinburgh, Edinburgh, UK; Nuffield Department of Clinical Medicine, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Dishon Muloi
- International Livestock Research Institute, Nairobi, Kenya; Centre for Immunity, Infection and Evolution, University of Edinburgh, Edinburgh, UK; Usher Institute of Population Health Sciences and Informatics, University of Edinburgh, Edinburgh, UK
| | - Judy M Bettridge
- Institute of Infection and Global Health, University of Liverpool, Neston, UK; International Livestock Research Institute, Nairobi, Kenya
| | | | - Sam Kariuki
- Centre for Microbiology Research, Kenya Medical Research Institute, Nairobi, Kenya
| | - Allan Ogendo
- International Livestock Research Institute, Nairobi, Kenya
| | - John Kiiru
- Centre for Microbiology Research, Kenya Medical Research Institute, Nairobi, Kenya
| | | | | | - Elin M Öghren
- Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | - Nicola J Williams
- Institute of Infection and Global Health, University of Liverpool, Neston, UK
| | - Michael Begon
- Institute of Integrative Biology, University of Liverpool, Liverpool, UK
| | - Mark E J Woolhouse
- Centre for Immunity, Infection and Evolution, University of Edinburgh, Edinburgh, UK; Usher Institute of Population Health Sciences and Informatics, University of Edinburgh, Edinburgh, UK
| | - Eric M Fèvre
- Institute of Infection and Global Health, University of Liverpool, Neston, UK; International Livestock Research Institute, Nairobi, Kenya.
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9
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de Glanville WA, Thomas LF, Cook EAJ, Bronsvoort BMDC, Wamae NC, Kariuki S, Fèvre EM. Household socio-economic position and individual infectious disease risk in rural Kenya. Sci Rep 2019; 9:2972. [PMID: 30814567 PMCID: PMC6393457 DOI: 10.1038/s41598-019-39375-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Accepted: 01/22/2019] [Indexed: 11/21/2022] Open
Abstract
The importance of household socio-economic position (SEP) in shaping individual infectious disease risk is increasingly recognised, particularly in low income settings. However, few studies have measured the extent to which this association is consistent for the range of pathogens that are typically endemic among the rural poor in the tropics. This cross-sectional study assessed the relationship between SEP and human infection within a single community in western Kenya using a set of pathogens with diverse transmission routes. The relationships between household SEP and individual infection with Plasmodium falciparum, hookworm (Ancylostoma duodenale and/or Necator americanus), Entamoeba histolytica/dispar, Mycobacterium tuberculosis, and HIV, and co-infections between hookworm, P. falciparum and E. histolytica/dispar, were assessed using multivariable logistic and multinomial regression. Individuals in households with the lowest SEP were at greatest risk of infection with P. falciparum, hookworm and E. histolytica/dispar, as well as co-infection with each pathogen. Infection with M. tuberculosis, by contrast, was most likely in individuals living in households with the highest SEP. There was no evidence of a relationship between individual HIV infection and household SEP. We demonstrate the existence of a household socio-economic gradient within a rural farming community in Kenya which impacts upon individual infectious disease risk. Structural adjustments that seek to reduce poverty, and therefore the socio-economic inequalities that exist in this community, would be expected to substantially reduce overall infectious disease burden. However, policy makers and researchers should be aware that heterogeneous relationships can exist between household SEP and infection risk for different pathogens in low income settings.
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Affiliation(s)
- W A de Glanville
- Centre for Immunity, Infection and Evolution, Institute for Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Ashworth Laboratories, West Mains Road, Edinburgh, EH9 3JT, UK.
- International Livestock Research Institute, Old Naivasha Road, PO BOX 30709, 00100, Nairobi, Kenya.
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, G12 8QQ, United Kingdom.
| | - L F Thomas
- Centre for Immunity, Infection and Evolution, Institute for Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Ashworth Laboratories, West Mains Road, Edinburgh, EH9 3JT, UK
- International Livestock Research Institute, Old Naivasha Road, PO BOX 30709, 00100, Nairobi, Kenya
| | - E A J Cook
- Centre for Immunity, Infection and Evolution, Institute for Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Ashworth Laboratories, West Mains Road, Edinburgh, EH9 3JT, UK
- International Livestock Research Institute, Old Naivasha Road, PO BOX 30709, 00100, Nairobi, Kenya
| | - B M de C Bronsvoort
- The Royal (Dick) School of Veterinary Studies, University of Edinburgh, Roslin, Midlothian, EH25 9RG, UK
- Roslin Institute, The Royal (Dick) School of Veterinary Studies, University of Edinburgh, Roslin, Midlothian, EH25 9RG, UK
| | - N C Wamae
- School of Pharmacy and Health Sciences, United States International University-Africa, PO Box 14634-01000, Nairobi, Kenya
| | - S Kariuki
- Centre for Microbiology Research, Kenya Medical Research Institute, PO Box 19464-00200, Nairobi, Kenya
| | - E M Fèvre
- International Livestock Research Institute, Old Naivasha Road, PO BOX 30709, 00100, Nairobi, Kenya.
- Institute of Infection and Global Health, University of Liverpool, Leahurst Campus, Neston, CH64 7TE, UK.
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10
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Kavai S, Kariuki S. Increasing multidrug and fluoroquinolone resistance among Salmonella Typhi from sporadic outbreaks in Kenya. Int J Infect Dis 2019. [DOI: 10.1016/j.ijid.2018.11.119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
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11
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Muturi P, Yu J, Li J, Jiang M, Maina AN, Kariuki S, Mwaura FB, Wei H. Isolation and characterization of pectolytic bacterial pathogens infecting potatoes in Nakuru County, Kenya. J Appl Microbiol 2018; 124:1580-1588. [PMID: 29437273 DOI: 10.1111/jam.13730] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Revised: 01/21/2018] [Accepted: 02/07/2018] [Indexed: 11/28/2022]
Abstract
AIMS Isolation and characterization of pectolytic bacteria associated with soft rot disease of potatoes in Nakuru, Kenya, to provide the basis for the development of disease control measures. METHODS AND RESULTS Potato tubers showing symptoms of soft rot were collected from different farms in Molo and Mau Narok regions within Nakuru county. Isolation was done using crystal violet pectate medium (CVPM). Out of the 71 isolates that showed growth on CVPM, pathogenicity tests revealed that 36 of them had the ability to macerate tissues of potato tubers. All the isolates yielded a fragment of approximately 1500 bp after 16S rDNA amplification. Using the BIOLOG microbial identification system, 20 bacterial isolates were identified as Pectobacterium carotovorum subsp. carotovorum, 7 were Pseudomonas fluorescens B while 9 were Ps. fluorescens A. Y1/Y2 primers successfully amplified pectate lyase-encoding (pel) gene, approximately 434 bp, in all the 20 P. carotovorum species. The virulence of the isolated strains to cause disease, according to pectinolytic tests, varied with change in incubation temperature of the test samples. Pectobacterium carotovorum strains were the most virulent at 30°C while disease severity due to infection by Ps. fluorescens A strains was high at 20°C compared to the other isolates. CONCLUSION This study reveals the identity of pectolytic bacterial species from two genera, Pectobacterium and Pseudomonas, as causative agents of potato soft rot in Nakuru, Kenya. SIGNIFICANCE AND IMPACT OF THE STUDY Research findings from this study will aid in developing suitable risk mitigation methods for adoption by farmers to prevent losses due to soft rot.
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Affiliation(s)
- P Muturi
- Key Laboratory of Emerging Pathogens and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China.,University of Chinese Academy of Sciences, Beijing, China
| | - J Yu
- Key Laboratory of Emerging Pathogens and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China
| | - J Li
- Key Laboratory of Emerging Pathogens and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China
| | - M Jiang
- Key Laboratory of Emerging Pathogens and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China
| | - A N Maina
- School of Biological and Life Sciences, Technical University of Kenya, Nairobi, Kenya.,School of Biological Sciences, University of Nairobi, Nairobi, Kenya
| | - S Kariuki
- Centre of Microbiology Research, Kenya Medical Research Institute, Nairobi, Kenya
| | - F B Mwaura
- School of Biological Sciences, University of Nairobi, Nairobi, Kenya
| | - H Wei
- Key Laboratory of Emerging Pathogens and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China.,Sino-Africa Joint Research Centre, Nairobi, Kenya
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12
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Pavlinac PB, Singa BO, John-Stewart GC, Richardson BA, Brander RL, McGrath CJ, Tickell KD, Amondi M, Rwigi D, Babigumira JB, Kariuki S, Nduati R, Walson JL. Azithromycin to prevent post-discharge morbidity and mortality in Kenyan children: a protocol for a randomised, double-blind, placebo-controlled trial (the Toto Bora trial). BMJ Open 2017; 7:e019170. [PMID: 29289941 PMCID: PMC5778294 DOI: 10.1136/bmjopen-2017-019170] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
INTRODUCTION Child mortality due to infectious diseases remains unacceptably high in much of sub-Saharan Africa. Children who are hospitalised represent an accessible population at particularly high risk of death, both during and following hospitalisation. Hospital discharge may be a critical time point at which targeted use of antibiotics could reduce morbidity and mortality in high-risk children. METHODS AND ANALYSIS In this randomised, double-blind, placebo-controlled trial (Toto Bora Trial), 1400 children aged 1-59 months discharged from hospitals in Western Kenya, in Kisii and Homa Bay, will be randomised to either a 5-day course of azithromycin or placebo to determine whether a short course of azithromycin reduces rates of rehospitalisation and/or death in the subsequent 6-month period. The primary analysis will be modified intention-to-treat and will compare the rates of rehospitalisation or death in children treated with azithromycin or placebo using Cox proportional hazard regression. The trial will also evaluate the effect of a short course of azithromycin on enteric and nasopharyngeal infections and cause-specific morbidities. We will also identify risk factors for postdischarge morbidity and mortality and subpopulations most likely to benefit from postdischarge antibiotic use. Antibiotic resistance in Escherichia coli and Streptococcus pneumoniae among enrolled children and their primary caregivers will also be assessed, and cost-effectiveness analyses will be performed to inform policy decisions. ETHICS AND DISSEMINATION Study procedures were reviewed and approved by the institutional review boards of the Kenya Medical Research Institute, the University of Washington and the Kenyan Pharmacy and Poisons Board. The study is being externally monitored, and a data safety and monitoring committee has been assembled to monitor patient safety and to evaluate the efficacy of the intervention. The results of this trial will be published in peer-reviewed scientific journals and presented at relevant academic conferences and to key stakeholders. TRIAL REGISTRATION NUMBER NCT02414399.
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Affiliation(s)
- Patricia B Pavlinac
- Department of Global Health, University of Washington, Seattle, Washington, USA
| | - Benson O Singa
- Centre for Clinical Research, Kenya Medical Research Institute, Nairobi, Kenya
- Childhood Acute Illness and Nutrition Network, Nairobi, Kenya
| | - Grace C John-Stewart
- Department of Global Health, University of Washington, Seattle, Washington, USA
- Department of Epidemiology, University of Washington, Seattle, Washington, USA
- Department of Pediatrics, University of Washington, Seattle, Washington, USA
- Department of Allergy and Infectious Disease, University of Washington, Seattle, Washington, USA
| | - Barbra A Richardson
- Department of Global Health, University of Washington, Seattle, Washington, USA
- Department of Biostatistics, University of Washington, Seattle, Washington, USA
| | - Rebecca L Brander
- Department of Epidemiology, University of Washington, Seattle, Washington, USA
| | - Christine J McGrath
- Department of Global Health, University of Washington, Seattle, Washington, USA
| | - Kirkby D Tickell
- Department of Global Health, University of Washington, Seattle, Washington, USA
- Childhood Acute Illness and Nutrition Network, Nairobi, Kenya
| | - Mary Amondi
- Centre for Clinical Research, Kenya Medical Research Institute, Nairobi, Kenya
| | - Doreen Rwigi
- Centre for Clinical Research, Kenya Medical Research Institute, Nairobi, Kenya
| | - Joseph B Babigumira
- Department of Global Health, University of Washington, Seattle, Washington, USA
- Department of Pharmacy, University of Washington, Seattle, Washington, USA
| | - Sam Kariuki
- Centre for Microbiology Research, Kenya Medical Research Institute, Nairobi, Kenya
| | - Ruth Nduati
- Department of Pediatrics, School of Medicine, University of Nairobi, Nairobi, Kenya
| | - Judd L Walson
- Department of Global Health, University of Washington, Seattle, Washington, USA
- Childhood Acute Illness and Nutrition Network, Nairobi, Kenya
- Department of Epidemiology, University of Washington, Seattle, Washington, USA
- Department of Pediatrics, University of Washington, Seattle, Washington, USA
- Department of Allergy and Infectious Disease, University of Washington, Seattle, Washington, USA
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13
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Njeru J, Tomaso H, Mertens K, Henning K, Wareth G, Heller R, Kariuki S, Fèvre EM, Neubauer H, Pletz MW. Serological evidence of Francisella tularensis in febrile patients seeking treatment at remote hospitals, northeastern Kenya, 2014-2015. New Microbes New Infect 2017; 19:62-66. [PMID: 28721222 PMCID: PMC5498284 DOI: 10.1016/j.nmni.2017.05.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Revised: 05/16/2017] [Accepted: 05/29/2017] [Indexed: 11/02/2022] Open
Abstract
Tularaemia is a highly contagious infectious zoonosis caused by the bacterial agent Francisella tularensis. The aim of this study was to investigate the presence of antibodies to F. tularensis in febrile patients in northeastern Kenya. During 2014-2015, 730 patients were screened for anti-F. tularensis antibodies using a combination of ELISA and Western blot. Twenty-seven (3.7%) individuals were positive for F. tularensis. Tularaemia was not suspected by the treating clinicians in any of them. Our results suggest that tularaemia may be present in Kenya but remain unreported, and emphasizes the need for local clinicians to broaden their diagnostic repertoire when evaluating patients with undifferentiated febrile illness.
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Affiliation(s)
- J Njeru
- Institute of Bacterial Infections and Zoonoses, Friedrich-Loeffler-Institute, Jena, Germany.,Centre for Infectious Diseases and Infection Control, Jena University Hospital, Jena, Germany.,Centre for Microbiology Research, Kenya Medical Research Institute, Nairobi, Kenya
| | - H Tomaso
- Institute of Bacterial Infections and Zoonoses, Friedrich-Loeffler-Institute, Jena, Germany
| | - K Mertens
- Institute of Bacterial Infections and Zoonoses, Friedrich-Loeffler-Institute, Jena, Germany
| | - K Henning
- Institute of Bacterial Infections and Zoonoses, Friedrich-Loeffler-Institute, Jena, Germany
| | - G Wareth
- Institute of Bacterial Infections and Zoonoses, Friedrich-Loeffler-Institute, Jena, Germany.,Faculty of Veterinary Medicine, Benha University, Moshtohor, Egypt
| | - R Heller
- Institute for Molecular Cell Biology, Center for Molecular Biomedicine, Friedrich Schiller University of Jena, Jena, Germany
| | - S Kariuki
- Centre for Microbiology Research, Kenya Medical Research Institute, Nairobi, Kenya
| | - E M Fèvre
- Institute of Infection and Global Health, University of Liverpool, Liverpool, UK.,International Livestock Research Institute, Nairobi, Kenya
| | - H Neubauer
- Institute of Bacterial Infections and Zoonoses, Friedrich-Loeffler-Institute, Jena, Germany
| | - M W Pletz
- Centre for Infectious Diseases and Infection Control, Jena University Hospital, Jena, Germany
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14
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Robinson TP, Bu DP, Carrique-Mas J, Fèvre EM, Gilbert M, Grace D, Hay SI, Jiwakanon J, Kakkar M, Kariuki S, Laxminarayan R, Lubroth J, Magnusson U, Thi Ngoc P, Van Boeckel TP, Woolhouse MEJ. Antibiotic resistance is the quintessential One Health issue. Trans R Soc Trop Med Hyg 2016; 110:377-80. [PMID: 27475987 PMCID: PMC4975175 DOI: 10.1093/trstmh/trw048] [Citation(s) in RCA: 376] [Impact Index Per Article: 47.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Revised: 06/28/2016] [Accepted: 06/30/2016] [Indexed: 11/21/2022] Open
Affiliation(s)
- T P Robinson
- International Livestock Research Institute, Nairobi, Kenya
| | - D P Bu
- Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, China
| | - J Carrique-Mas
- Oxford University Clinical Research Unit, Wellcome Trust Major Overseas Programme, Ho Chi Minh City, Vietnam
| | - E M Fèvre
- Institute of Infection and Global Health, University of Liverpool, Liverpool, UK
| | - M Gilbert
- Université Libre de Bruxelles, Brussels, Belgium
| | - D Grace
- International Livestock Research Institute, Nairobi, Kenya
| | - S I Hay
- Institute for Health Metrics and Evaluation, University of Washington, Seattle, USA Oxford Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, Oxford, UK
| | - J Jiwakanon
- Research Group for Preventive Technology in Livestock, Faculty of Veterinary Medicine, Khon Kaen University, Khon Kaen, Thailand
| | - M Kakkar
- Public Health Foundation of India, Delhi, India
| | - S Kariuki
- Kenya Medical Research Institute, Nairobi, Kenya
| | - R Laxminarayan
- Center for Disease Dynamics, Economics and Policy, Washington DC, USA
| | - J Lubroth
- Food and Agriculture Organization of the United Nations, Rome, Italy
| | - U Magnusson
- Department of Clinical Sciences, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - P Thi Ngoc
- National Institute of Veterinary Research, Hanoi, Vietnam
| | - T P Van Boeckel
- Institute of Integrative Biology and Center for Adaptation to a Changing Environment, Swiss Federal Institute of Technology, Zurich, Switzerland
| | - M E J Woolhouse
- Centre for Immunity, Infection & Evolution, University of Edinburgh, Edinburgh, UK
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15
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Mbae C, Mulinge E, Guleid F, Wainaina J, Waruru A, Njiru ZK, Kariuki S. Molecular Characterization of Giardia duodenalis in Children in Kenya. BMC Infect Dis 2016; 16:135. [PMID: 27005473 PMCID: PMC4802924 DOI: 10.1186/s12879-016-1436-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Accepted: 02/16/2016] [Indexed: 01/20/2023] Open
Abstract
Background Giardia duodenalis is an important intestinal protozoan in humans worldwide with high infection rates occurring in densely populated and low resource settings. The parasite has been recorded to cause diarrhea in children. This study was carried out to identify G. duodenalis assemblages and sub-assemblages in children presenting with diarrhea in Kenya. Methods A total of 2112 faecal samples were collected from children aged ≤5 years and screened for the presence of Giardia cysts using microscopy. A total of 96 (4.5 %) samples were identified as Giardia positive samples and were genotyped using glutamate dehydrogenase (gdh), triose phosphate isomerase (tpi) and β-giardin loci. Results The three markers successfully genotyped 72 isolates and grouped 2 (1.4) isolates as Assemblage A, 64 (88.9) as Assemblage B and 7 (9.7 %) consisted of mixed infections with assemblage A and B. A further analysis of 50 isolates using GDH Polymerase Chain Reaction and Restriction Fragment Length Polymorphism (PCR-RFLP) categorized 2 assemblage A isolates as sub-assemblage AII while 6 and 14 assemblage B isolates were categorized into sub-assemblage BIII and BIV respectively. A mixed infection with sub-assemblage BIII and BIV was recorded in 28 isolates. Over half (55.6 %) of Giardia infections were recorded among the children between 13 to 48 months old. Conclusion This paper reports the first data on the assemblages and sub-assemblages of Giardia duodenalis in children representing with diarrhea in Kenya.
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Affiliation(s)
- C Mbae
- Centre for Microbiological Research, KEMRI, P.O Box 19464-00202, Nairobi, Kenya.
| | - E Mulinge
- Centre for Microbiological Research, KEMRI, P.O Box 19464-00202, Nairobi, Kenya
| | - F Guleid
- Centre for Microbiological Research, KEMRI, P.O Box 19464-00202, Nairobi, Kenya
| | - J Wainaina
- International Livestock Research Institute, Naivasha Rd, P.O Box 30709, Nairobi, Kenya
| | - A Waruru
- Kenya Medical Research Institute, P. O Box 58540-00200, Nairobi, Kenya
| | - Z K Njiru
- Murdoch University, School of Health Professions, Peel Campus, Mandurah, WA, 6210, Australia
| | - S Kariuki
- Centre for Microbiological Research, KEMRI, P.O Box 19464-00202, Nairobi, Kenya
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16
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Neafsey DE, Juraska M, Bedford T, Benkeser D, Valim C, Griggs A, Lievens M, Abdulla S, Adjei S, Agbenyega T, Agnandji ST, Aide P, Anderson S, Ansong D, Aponte JJ, Asante KP, Bejon P, Birkett AJ, Bruls M, Connolly KM, D'Alessandro U, Dobaño C, Gesase S, Greenwood B, Grimsby J, Tinto H, Hamel MJ, Hoffman I, Kamthunzi P, Kariuki S, Kremsner PG, Leach A, Lell B, Lennon NJ, Lusingu J, Marsh K, Martinson F, Molel JT, Moss EL, Njuguna P, Ockenhouse CF, Ogutu BR, Otieno W, Otieno L, Otieno K, Owusu-Agyei S, Park DJ, Pellé K, Robbins D, Russ C, Ryan EM, Sacarlal J, Sogoloff B, Sorgho H, Tanner M, Theander T, Valea I, Volkman SK, Yu Q, Lapierre D, Birren BW, Gilbert PB, Wirth DF. Genetic Diversity and Protective Efficacy of the RTS,S/AS01 Malaria Vaccine. N Engl J Med 2015; 373:2025-2037. [PMID: 26488565 PMCID: PMC4762279 DOI: 10.1056/nejmoa1505819] [Citation(s) in RCA: 264] [Impact Index Per Article: 29.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
BACKGROUND The RTS,S/AS01 vaccine targets the circumsporozoite protein of Plasmodium falciparum and has partial protective efficacy against clinical and severe malaria disease in infants and children. We investigated whether the vaccine efficacy was specific to certain parasite genotypes at the circumsporozoite protein locus. METHODS We used polymerase chain reaction-based next-generation sequencing of DNA extracted from samples from 4985 participants to survey circumsporozoite protein polymorphisms. We evaluated the effect that polymorphic positions and haplotypic regions within the circumsporozoite protein had on vaccine efficacy against first episodes of clinical malaria within 1 year after vaccination. RESULTS In the per-protocol group of 4577 RTS,S/AS01-vaccinated participants and 2335 control-vaccinated participants who were 5 to 17 months of age, the 1-year cumulative vaccine efficacy was 50.3% (95% confidence interval [CI], 34.6 to 62.3) against clinical malaria in which parasites matched the vaccine in the entire circumsporozoite protein C-terminal (139 infections), as compared with 33.4% (95% CI, 29.3 to 37.2) against mismatched malaria (1951 infections) (P=0.04 for differential vaccine efficacy). The vaccine efficacy based on the hazard ratio was 62.7% (95% CI, 51.6 to 71.3) against matched infections versus 54.2% (95% CI, 49.9 to 58.1) against mismatched infections (P=0.06). In the group of infants 6 to 12 weeks of age, there was no evidence of differential allele-specific vaccine efficacy. CONCLUSIONS These results suggest that among children 5 to 17 months of age, the RTS,S vaccine has greater activity against malaria parasites with the matched circumsporozoite protein allele than against mismatched malaria. The overall vaccine efficacy in this age category will depend on the proportion of matched alleles in the local parasite population; in this trial, less than 10% of parasites had matched alleles. (Funded by the National Institutes of Health and others.).
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Jost J, Sivadier G, Ba A, Ngoungou E, Kariuki S, Ratsimbazafy V, Preux P, Newton C. Quality of antiepileptic drugs in Africa: Results from a pilot study (Quaeda) in Kenya and Gabon. J Neurol Sci 2015. [DOI: 10.1016/j.jns.2015.08.155] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Laxminarayan R, Duse A, Wattal C, Zaidi AKM, Wertheim HFL, Sumpradit N, Vlieghe E, Hara GL, Gould IM, Goossens H, Greko C, So AD, Bigdeli M, Tomson G, Woodhouse W, Ombaka E, Peralta AQ, Qamar FN, Mir F, Kariuki S, Bhutta ZA, Coates A, Bergstrom R, Wright GD, Brown ED, Cars O. Antibiotic resistance-the need for global solutions. Lancet Infect Dis 2013; 13:1057-98. [PMID: 24252483 DOI: 10.1016/s1473-3099(13)70318-9] [Citation(s) in RCA: 2479] [Impact Index Per Article: 225.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The causes of antibiotic resistance are complex and include human behaviour at many levels of society; the consequences affect everybody in the world. Similarities with climate change are evident. Many efforts have been made to describe the many different facets of antibiotic resistance and the interventions needed to meet the challenge. However, coordinated action is largely absent, especially at the political level, both nationally and internationally. Antibiotics paved the way for unprecedented medical and societal developments, and are today indispensible in all health systems. Achievements in modern medicine, such as major surgery, organ transplantation, treatment of preterm babies, and cancer chemotherapy, which we today take for granted, would not be possible without access to effective treatment for bacterial infections. Within just a few years, we might be faced with dire setbacks, medically, socially, and economically, unless real and unprecedented global coordinated actions are immediately taken. Here, we describe the global situation of antibiotic resistance, its major causes and consequences, and identify key areas in which action is urgently needed.
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Affiliation(s)
- Ramanan Laxminarayan
- Center for Disease Dynamics, Economics and Policy, Washington, DC, USA; Princeton University, Princeton NJ, USA; Public Health Foundation of India, New Delhi, India
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Dinda V, Gunturu R, Kariuki S, Hakeem A, Raja A, Kimang'a A. Pattern of pathogens and their sensitivity isolated from surgical site infections at the Aga Khan University Hospital, Nairobi, Kenya. Ethiop J Health Sci 2013; 23:141-9. [PMID: 23950630 PMCID: PMC3742891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
BACKGROUND In low income countries, surgical site infections (SSIs) are costly and impose a heavy and potentially preventable burden on both patients and healthcare providers. This study aimed to determine the occurrence of SSI, pathogens associated with SSI, the antibiogram of the causative pathogens and specific risk factors associated with SSI at the hospital. METHODS Two hundred and sixty-eight respondents admitted for general surgical procedures (other than neurological and cardiothoracic surgeries) at the Aga Khan University Hospital were eligible to take part in the study. Post-surgery patients were observed for symptoms of infection. Follow ups were done through the consulting clinics, breast clinic and casualty dressing clinic by a team of surgeons. In cases of infection, pus swabs were collected for culture. RESULTS SSI incidence rate was 7.0%, pathogens isolated from SSI included gram negative enteric bacilli and S. aureus which was the most prevalent bacterial isolate. Only one isolate of MRSA was found and all staphylococci were susceptible to Vancomycin. Preoperative stay ≥ 2 days and wound class were the risk factors associated with SSI. CONCLUSION The SSI incidence rates (7.0%) observed in this study were relatively lower than the ones documented in other studies in Kenya. S. aureus is the most prevalent pathogen associated with SSI. Similar to findings from other studies done in the region; prolonged hospital stay and dirty wounds were the risks associated with postsurgical sepsis at the hospital.
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Affiliation(s)
- Victor Dinda
- Department of Medical laboratory science, School of Health sciences, Masinde Muliro University of Science and Technology
| | - Revathi Gunturu
- Department of Pathology, Aga Khan University Hospital Nairobi, Kenya
| | - Sam Kariuki
- Center of Microbiology Research, Kenya Institute Medical Research Institute, Kenya
| | - Abdi Hakeem
- Department of Surgery, Aga Khan University Hospital Nairobi, Kenya
| | - Asad Raja
- Department of Surgery, Aga Khan University Hospital Nairobi, Kenya
| | - Andrew Kimang'a
- Department of Medical Microbiology, College of Health Sciences, Jomo Kenyatta University of Agriculture & Technology, Kenya
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Njoroge S, Muigai AWT, Njiruh PN, Kariuki S. MOLECULAR CHARACTERISATION AND ANTIMICROBIAL RESISTANCE PATTERNS OF ESCHERICHIA COLI ISOLATES FROM GOATS SLAUGHTERED IN PARTS OF KENYA. East Afr Med J 2013; 90:72-83. [PMID: 26866105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
OBJECTIVE To determine the antibiotic resistance patterns of pathogenic Escherichia coli on goat meat carcass at Huruma and Kiserian abattoirs in Kenya. DESIGN Laboratory based study. SETTING Huruma and Kiserian abattoirs in Kenya, SUBJECTS 400 slaughtered goats inspected by veterinary health officers and approved for human consumption. METHODS A Total of 400 slaughtered goats which were inspected by veterinary health officers and approved for human consumption were sampled from Huruma and Kiserian abattoir. Goat carcass swabs were collected by passing each swab tissue on four parts of the carcass mainly neck, right and left forelimbs, right and left hind limbs, and brisket. RESULTS A total of 54 E. coli isolates were isolated and confirmed to be pathogenic. The percentage of isolates resistant to various microbial agents was recorded as follows: ampicillin (26 %), amoxycillin-clavulanic acid (17%), tetracycline (15%), chroramphenicol (4%), and ceftrixone (2% each). All Escherichia coli isolates were susceptible to gentamicin sulphamethaxazole-trimethomprin, kanamycin, cetriazididine (CAZ, 30pg), ciproxacin, nalidixic acid and chloramphenicol. Isolates were resistant to one or more of the antibiotics tested. Among the drugs tested, resistance was more frequently observed against ampicillin, amoxycillin-clavulanic acid, tetracycline, ceftrixone and chroramphenicol antibiotics. Among the isolates 26(48%) were positive for the stx1 gene, 19(35%) had the eae gene, 10(19%) possessed est gene,while 8(15%) harboured elt gene. Overall five isolates (10%) possessed aspu gene and two (4%) had aggR gene. No isolate possessed ipah gene. CONCLUSION This study demonstrated that there is a significant level of antimicrobial resistance in pathogenic E. coli isolated from goat meat from Huruma and Kiserian abattoir. This indicates that goat meat from abattoirs could pose a risk of transmission of pathogenic antibiotic resistant strains to human. Poor hygienic standards and indiscriminate use of antimicrobials are the two main reasons for the presence of resistant pathogens in goat carcasses. RECOMMENDATIONS Implemention of appropriate hygiene measures to control contamination of meat with pathogenic E. coli.
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Affiliation(s)
- S Njoroge
- Institute of Tropical Medicine and Infectious Diseases, Jomo Kenyatta University of Agriculture and Technology, PO Box 62000-00200, Nairobi, Kenya
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Maina EK, Kiiyukia C, Wamae CN, Waiyaki PG, Kariuki S. Characterization of methicillin-resistant Staphylococcus aureus from skin and soft tissue infections in patients in Nairobi, Kenya. Int J Infect Dis 2012; 17:e115-9. [PMID: 23092752 DOI: 10.1016/j.ijid.2012.09.006] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2012] [Revised: 07/24/2012] [Accepted: 09/14/2012] [Indexed: 10/27/2022] Open
Abstract
BACKGROUND Skin and soft tissue infections (SSTIs) are among the most common infectious diseases and a frequent cause of hospital visits. In this study we sought to assess the prevalence of methicillin-resistant Staphylococcus aureus (MRSA) and antibiotic susceptibility patterns in SSTIs in patients attending hospitals in Kenya. METHODS Eighty-two S. aureus isolates recovered from SSTIs from both inpatients and outpatients were screened for antibiotic susceptibility, possession of staphylococcal cassette chromosome mec (SCCmec) gene type, and the Panton-Valentine leukocidin (PVL) toxin gene. The prevalence of MRSA was investigated in relation to the type of patient and infection type, as well as the type of health care facility. RESULTS Of 60 boil cultures, 39 (65%) grew S. aureus, of out of which 34 (87.2%) were MRSA. Of the 60 abscess cultures, 14 (23.3%) grew S. aureus, of which 10 (71.4%) were MRSA. Of 34 cellulitis cultures, 18 (52.9%) grew S. aureus, of which 16 (88.8%) were MRSA. Of 25 ulcer cultures, 11 (44%) grew S. aureus, of which nine (81.8%) were MRSA. Sixty-nine of 82 S. aureus (84.1%) were MRSA, with 52 (75.4%) possessing SCCmec II type and 14 (20.3%) being positive for the PVL gene. Based on hospitals, it was noted that most MRSA were isolated at publicly funded health care facilities serving an economically disadvantaged segment of Nairobi's population, such as those living in urban informal settlements. All 82 S. aureus were susceptible to vancomycin and resistant in high numbers to macrolides, aminoglycosides, and quinolones. Bacterial isolates were mostly susceptible to vancomycin, ciprofloxacin and co-trimoxazole, and none was resistant to vancomycin. However, most organisms showed decreased susceptibility to erythromycin and clindamycin. CONCLUSIONS These findings suggest that SCCmec II MRSA and a PVL strain of MRSA are significant pathogens in patients with SSTIs presenting to hospitals in Kenya, and that MRSA cases are prevalent at publicly funded health care facilities.
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Affiliation(s)
- Edward K Maina
- Centre for Microbiology Research, Kenya Medical Research Institute, P.O Box 19464-00202 Nairobi, Kenya
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Omuse G, Kariuki S, Revathi G. Unexpected absence of meticillin-resistant Staphylococcus aureus nasal carriage by healthcare workers in a tertiary hospital in Kenya. J Hosp Infect 2011; 80:71-3. [PMID: 22104475 DOI: 10.1016/j.jhin.2011.09.009] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2011] [Accepted: 09/14/2011] [Indexed: 10/15/2022]
Abstract
Healthcare workers (HCWs) are a major reservoir of meticillin-resistant Staphylococcus aureus (MRSA). A cross-sectional study was conducted between July and December 2010 to determine the prevalence of nasal carriage of MRSA at the Aga Khan University Hospital Nairobi. Nasal swabs were taken from 246 randomly selected HCWs. MRSA was identified using both phenotypic and genotypic methods. The prevalence of MRSA carriage was 0% [95% confidence interval (CI): 0-1.5%] whereas that of meticillin-susceptible Staphylococcus aureus was 18.3% (95% CI: 14.0-23.6%). Given the absence of MRSA in our hospital, screening HCWs should be limited to an outbreak setting.
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Affiliation(s)
- G Omuse
- Aga Khan University Hospital Nairobi, Nairobi, Kenya.
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Saidi SM, Yamasaki S, Lijima Y, Kariuki S. Cholera-like diarrhoea due to Salmonella infection. J Infect Dev Ctries 2011; 5:68-70. [PMID: 21330744 DOI: 10.3855/jidc.1168] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2010] [Revised: 08/17/2010] [Accepted: 08/17/2010] [Indexed: 10/31/2022] Open
Abstract
An unusually high number of sporadic cholera outbreaks have occurred in various parts of Kenya since January 2009. Clinical symptoms of cholera play an important role in the diagnosis and management of the disease, especially in resource-poor settings in most developing countries. We describe a case report of a patient who was treated for cholera according to symptoms at presentation to hospital. Non-typhoid Salmonella was later isolated and the patient's condition improved after administration of ciprofloxacin.
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Affiliation(s)
- Suleiman Mzee Saidi
- Centre for Microbiology Research, Kenya Medical Research Institute, Nairobi, Kenya.
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Kimang'a A, Revathi G, Kariuki S, Sayed S, Devani S, Vivienne M, Kuester D, Mönkemüller K, Malfertheiner P, Wex T. IL-17A and IL-17F gene expression is strongly induced in the mucosa of H. pylori-infected subjects from Kenya and Germany. Scand J Immunol 2011; 72:522-8. [PMID: 21044126 DOI: 10.1111/j.1365-3083.2010.02469.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Helicobacter pylori infection is the major cause of gastritis. Immunologically, H. pylori gastritis is associated with an infiltration of immune cells into gastric mucosa and the upregulation of various cytokines. Here, we analysed the gene expression of IL-1- and IL-17-related cytokines in regard to H. pylori infection in 85 German and 51 Kenyan patients with reflux-related or dyspeptic symptoms, respectively. Degree of gastritis and density of colonization were assessed histologically in accordance with the updated Sydney classification. Gene expression levels of cytokines IL-1β, IL-8, IL-18, IL-33, IL-17A, IL-17F and IL-23 as well as IL-23R were analysed by real-time RT-PCR. In both populations, H. pylori-infected individuals had significant higher inflammatory scores for activity and chronicity than H. pylori-negative subjects (P values between 0.006 and <0.0001). IL-8 mRNA was induced up to 6-fold in H. pylori-infected patients (P < 0.05), while the expression levels of IL-1β, IL-18, IL-23, IL-33 and IL-23R did not differ with respect to the H. pylori status in both groups. Most strikingly, a significant induction of both IL-17A and IL-17F was noted in H. pylori-infected individuals of both ethnic groups. Almost all IL-17F-positive samples revealed co-expression of IL-17A (40/42, 95.2%). Analysing IL-17A and IL-17F transcript levels of these 40 'double-positive' samples, a highly significant positive correlation between both genes was identified (P < 0.001). Taken together, H. pylori infection leads to a strong upregulation of both IL-17A and IL-17F in the gastric mucosa suggesting a regulatory link between both genes.
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Affiliation(s)
- A Kimang'a
- Sub-Department of Medical Microbiology, Jomo Kenyatta University of Agriculture and Technology, Nairobi, Kenya
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Mengo DM, Kariuki S, Muigai A, Revathi G. Trends in Salmonella enteric serovar Typhi in Nairobi, Kenya from 2004 to 2006. J Infect Dev Ctries 2010; 4:393-396. [PMID: 20601792] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2009] [Revised: 03/08/2010] [Accepted: 03/16/2010] [Indexed: 05/29/2023] Open
Abstract
BACKGROUND Typhoid fever is a global health problem. The World Health Organization (WHO) estimates that the current annual global burden of typhoid is approximately 22 million new cases, 5% of which are fatal. METHODOLOGY To assess the trends in antibiotic resistance in 100 Salmonella enterica serovar Typhi strains were isolated from the blood of patients in Nairobi, Kenya, from 2004 to 2006. All isolates were tested against ampicilin, chloramphenic, nalidixic acid, ciprofloxacin, cotrimoxazole, cefuroxime, cefriaxone, amoxycillin/clavulanic acid, tetracycline and gentamycin. Susceptibility and resistance were determined using MIC and disk diffusion tests. RESULTS From 2004 to 2006 a total of 100 strains were studied; 70% of the isolates were multidrug resistant (MDR) while 15% of the isolates were sensitive to all drugs tested. Of 13 isolates that were resistant to ciprofloxacin and nalidixic acid by disk diffusion, 11 had an MIC of 0. 25 microg/ml while two isolates had an MIC of 1.00 microg,/ml. Resistance in ampicillin decreased from 88% in 2004 to 64% in 2005; this increased to 76% in 2006. Similar trends were observed for four other antibiotics tested. CONCLUSION The prescription of first-line antibiotics used in the treatment of S. Typhi should be stopped temporarily. Drugs such as cipfloxacin would be useful in the treatment of typhoid caused by MDR S. Typhi. There is need to monitor the resistance in flouroquinolones as resistance to these drugs has been observed and they are the current drugs used to treat typhoid.
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Affiliation(s)
- Doris Mueni Mengo
- Institute of Tropical Medicine and Infectious Diseases, Jomo Kenyatta University of Agriculture and Technology, Nairobi, Kenya.
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Oundo JO, Iijima Y, Boga HI, Muli F, Kariuki S. Molecular typing and antibiotic susceptibility patterns of enteropathogenic and shigatoxin producing Escherichia coli isolated from food handlers in three areas of Kenya. ACTA ACUST UNITED AC 2010; 86:279-86. [PMID: 20358790 DOI: 10.4314/eamj.v86i6.54140] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
OBJECTIVES To determine the aetiology, epidemiology and sanitary factors of carriage of enteropathogenic Escherichia coli (EPEC) and Shiga-toxin producing E. coli (STEC) in food-handlers working in tourist hotels in three popular tourist destinations in Kenya. DESIGN Cross sectional laboratory based study. SETTING Three tourist destinations of Nairobi, Malindi and Diani in Kenya. SUBJECTS Food handlers who were working in hotels frequented by tourists in the three study sites. RESULTS Overall, during the period of April 2003 to May 2004, a total of 1399 food handlers stool samples were collected and analysed. EPEC expressing the eaeA gene and STEC expressing the stx2 gene were detected in 11/1399 (0.8%) and 2/1399 (0.1%) of the study subjects respectively. The mean age of the subjects from whom EPEC and STEC were isolated was similar (32.6 years) to those from whom no EPEC and STEC were isolated (32.5 years). Prior use of antibiotics, water source and toilet types were not significantly associated with the isolation of EPEC and STEC (p>0.05). There were 11 resistance patterns with six isolates (6/13, 46.2%) showing multidrug resistance. High prevalence of resistance was observed to co-trimoxazole (55.6%), chloramphenicol (33.3%), ampicillin (22.2%) and tetracycline (22.2%). High concentrations of antibiotics were required to achieve MIC90 for tetracycline, (>64 mg ml(-1)) and ampicillin (>256 mg ml(-1)). Cluster analysis of the Pulse Field Gel Electrophoresis profiles revealed that the EPEC and STEC isolates belonged to two main genotypes with 11 distinct DNA fragment profiles. CONCLUSION This is the first report in Africa on the isolation of STEC from food handlers working in tourist hotels. These food handlers who carry the STEC and EPEC could potentially infect tourists and other people through food or water contamination in the hotel settings and thus our findings are of great public health importance.
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Affiliation(s)
- J O Oundo
- Kenya Medical Research Institute, Centre for Microbiology Research, P.O. Box 19464-00202, Nairobi, Kenya
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Mengo DM, Kariuki S, Muigai A, Revathi G. Trends in Salmonella enteric serovar Typhi in Nairobi, Kenya from 2004 to 2006. J Infect Dev Ctries 2010. [DOI: 10.3855/jidc.503] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Background: Typhoid fever is a global health problem. The World Health Organization (WHO) estimates that the current annual global burden of typhoid is approximately 22 million new cases, 5% of which are fatal. Methodology: To assess the trends in antibiotic resistance in 100 Salmonella enterica serovar Typhi strains were isolated from the blood of patients in Nairobi, Kenya, from 2004 to 2006. All isolates were tested against ampicilin, chloramphenic, nalidixic acid, ciprofloxacin, cotrimoxazole, cefuroxime, cefriaxone, amoxycillin/clavulanic acid, tetracycline and gentamycin. Susceptibility and resistance were determined using MIC and disk diffusion tests. Results: From 2004 to 2006 a total of 100 strains were studied; 70% of the isolates were multidrug resistant (MDR) while 15% of the isolates were sensitive to all drugs tested. Of 13 isolates that were resistant to ciprofloxacin and nalidixic acid by disk diffusion, 11 had an MIC of 0. 25 µg/ml while two isolates had an MIC of 1.00 µg,/ml. Resistance in ampicillin decreased from 88% in 2004 to 64% in 2005; this increased to 76% in 2006. Similar trends were observed for four other antibiotics tested. Conclusion: The prescription of first-line antibiotics used in the treatment of S. Typhi should be stopped temporarily. Drugs such as cipfloxacin would be useful in the treatment of typhoid caused by MDR S. Typhi. There is need to monitor the resistance in flouroquinolones as resistance to these drugs has been observed and they are the current drugs used to treat typhoid.
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Kariuki S. Antimicrobial-resistant bacterial infection in the era of HIV. East Afr Med J 2010; 87:177-178. [PMID: 23057278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
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Wesonga SM, Muluvi GM, Okemo PO, Kariuki S. Antibiotic resistant salmonella and Escherichia coli isolated from indigenous Gallus domesticus in Nairobi, Kenya. East Afr Med J 2010; 87:205-210. [PMID: 23057283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
OBJECTIVE To characterise and investigate antimicrobial resistance of Esherichia coli and salmonella strains isolated from indigenous Gallus gallus in a leading slaughterhouse/market outlet in Nairobi-Kenya. DESIGN A repeated cross sectional study and based on random sampling was used. SETTING The study was carried out in a leading market outlet in Nairobi, Kenya. RESULTS A hundred and four indigenous chicken rectal swabs were analysed, of which 67.3% were contaminated with Escherichia coli and 12.5% with Salmonella typhimurium. Seventy Escherichia coli isolates showed resistance phenotypes to one, two or more antibiotics. The most common antimicrobial resistance pattern was the single resistance to Tet (21.43%), followed by Amp Cot Tet (14%), Aug Amp Cot Tet (4.29%), Aug Amp Cot Tet Kan Chl (2.86%), Amp Cot Tet Chl, Cot Tet (2.86%) and Crx Amp Cot Tet Chl, Crx Amp Cot Chi, Amp Cot, Aug Amp, (1.43%) respectively. The highest rate of resistance was against Tet (55.7%), followed by Cot (40%). Third in line of resistance was Amp 32.86%, followed by Aug (11.43%), low or moderate resistance was against Chl (8.57%), Kan (4.29%), and Crx (2.86%) (P<0.0002). Salmonella typhimurium recovered displayed single resistance pattern to Tet (16.67%), Gen Cot Tet (8.33%), Amp Cot Tet (8.33%), Aug Amp Cot Tet (8.33%) and Amp Cot Tet Chl (16.67%). The highest resistance was against Tet (58.3%), Cot (41.7%), Amp (33.3%), Chl (16.7%), Aug and Gen (8.3%) respectively (P<0.0001). 3.0kb and 5.6kb plasmids isolated were not transferable by conjugation. CONCLUSION Routine surveillance at slaughter/market outlets of Escherichia coli and Salmonella enterica should be done to identify infected flocks as a regulatory procedure for food safety and security programme.
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Affiliation(s)
- S M Wesonga
- Department of Biochemistry and Biotechnology, Kenyatta University, P. O. Box 43844, Nairobi, Kenya
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Sifuna AW, Njagi ENM, Okemo P, Munyalo A, Orinda GO, Kariuki S. Microbiological quality and safety of Rastrineobola argentea retailed in Kisumu town markets, Kenya. ACTA ACUST UNITED AC 2009; 85:509-13. [PMID: 19537428 DOI: 10.4314/eamj.v85i10.9664] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
OBJECTIVE To investigate faecal contamination and safety of Rastrineobola argentea sold in retail markets in Kisumu town. DESIGN This was a repeated cross sectional study and based on random sampling. SETTING Kisumu city, targeting six markets; Oile, Jubilee, Kibuye, Kondele, Nyalenda and Manyatta. RESULTS A total of 60 fish samples were analysed. All the fish were found to be contaminated with E. coli, and in addition 6.67% of the fish products tested positive for Salmonella. Shigella was absent in all samples analysed. 26.53% of E. coli isolates tested were resistant to two or more antimicrobial agents tested, with the highest level of resistance detected against cotrimoxazole at 38.76%. The E. coli multiple antibiotic resistance (MAR) index was 0.084 indicating that the contamination was not originating from a high-risk source. A plasmid of approximately 5.6 kb was commonly isolated from E. coli isolates that showed resistance to ampicillin. Plasmids isolated were not transferable by conjugation. CONCLUSION The presence of Salmonella spp and occurrence of MDR E. coli were identified as some of the possible health risks that may be associated with R. argentea displayed for sale in Kisumu city markets. This possess a real health risk through consumption or directly through contact with the fish products.
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Affiliation(s)
- A W Sifuna
- Department of Biochemistry and Biotechnology, Kenyatta University, P.O. Box 43844, Nairobi, Kenya
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Bhattacharya S, Black R, Bourgeois L, Clemens J, Cravioto A, Deen JL, Dougan G, Glass R, Grais RF, Greco M, Gust I, Holmgren J, Kariuki S, Lambert PH, Liu MA, Longini I, Nair GB, Norrby R, Nossal GJV, Ogra P, Sansonetti P, von Seidlein L, Songane F, Svennerholm AM, Steele D, Walker R. The Cholera Crisis in Africa. Science 2009; 324:885. [DOI: 10.1126/science.1173890] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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Thwing JI, Odero CO, Odhiambo FO, Otieno KO, Kariuki S, Ord R, Roper C, McMorrow M, Vulule J, Slutsker L, Newman RD, Hamel MJ, Desai M. In-vivo efficacy of amodiaquine-artesunate in children with uncomplicated Plasmodium falciparum malaria in western Kenya. Trop Med Int Health 2009; 14:294-300. [PMID: 19187521 DOI: 10.1111/j.1365-3156.2009.02222.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
OBJECTIVES To assess the efficacy of amodiaquine-artesunate in an area with high chloroquine resistance in western Kenya. METHODS Twenty-eight day in-vivo efficacy trial of amodiaquine-artesunate in 103 children aged 6-59 months in western Kenya with smear-confirmed uncomplicated Plasmodium falciparum malaria. RESULTS The 28-day uncorrected adequate clinical and parasitological response (ACPR) was 69.0%, with 15.5% Late Clinical Failure and 15.5% Late Parasitologic Failure rates. The PCR-corrected 28-day ACPR was 90.2%. Clinical risk factors for recurrent infection (recrudescences and reinfections) were lower axillary temperature at enrollment and low weight-for-age Z-score. The presence of single nucleotide polymorphisms pfcrt 76T and pfmdr1 86Y at baseline was associated with increased risk of recurrent infections, both reinfections and recrudescences. CONCLUSION Although artemether-lumefantrine (Coartem) is the first line ACT in Kenya, amodiaquine-artesunate is registered as an option for treatment of uncomplicated P. falciparum and remains an effective alternative to Coartem in western Kenya. Continued amodiaquine monotherapy in the private sector may jeopardize the future use of amodiaquine-artesunate as an alternative artemisinin-based combination therapy.
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Affiliation(s)
- J I Thwing
- Malaria Branch, Division of Parasitic Diseases, Centers for Disease Control and Prevention, Atlanta, GA 30341, USA.
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Pitout JDD, Revathi G, Chow BL, Kabera B, Kariuki S, Nordmann P, Poirel L. Metallo-beta-lactamase-producing Pseudomonas aeruginosa isolated from a large tertiary centre in Kenya. Clin Microbiol Infect 2008; 14:755-9. [PMID: 18727799 DOI: 10.1111/j.1469-0691.2008.02030.x] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
This study was designed to characterize the beta-lactamase content of carbapenem-resistant Pseudomonas aeruginosa isolates recovered during 2006 and 2007 in a large tertiary-care centre in Nairobi, Kenya. Molecular characterization was done using PCR and sequencing, and typing was performed using pulsed-field gel electrophoresis (PFGE). In total, 416 P. aeruginosa isolates were obtained during that period, of which 57 (13.7%) were resistant to carbapenems. All carbapenem-resistant isolates tested positive for metallo-beta-lactamase (MBL) production. All MBL isolates produced VIM-2 with two types of integron structures. PFGE identified three clonally related groups of VIM-2-producing P. aeruginosa, including a pan-resistant clone that was responsible for nosocomial outbreaks during 2006 and 2007 in the intensive-care unit. These findings suggest that continuous molecular surveillance needs to be performed to monitor the spread within the hospital of this pan-resistant strain. This study is the first report of VIM-2-producing P. aeruginosa from the African continent.
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Affiliation(s)
- J D D Pitout
- Division of Microbiology, Calgary Laboratory Services, Department of Pathology & Laboratory Medicine, and Microbiology & Infectious Diseases, University of Calgary, Calgary, Alberta, Canada.
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Lwai-Lume L, Ogutu EO, Amayo EO, Kariuki S. Drug susceptibility pattern of Helicobacter pylori in patients with dyspepsia at the Kenyatta National Hospital, Nairobi. ACTA ACUST UNITED AC 2006; 82:603-8. [PMID: 16619703 DOI: 10.4314/eamj.v82i12.9364] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
OBJECTIVE To determine drug susceptibility pattern of Helicobacter pylori to metronidazole, clarithromycin, amoxicillin and tetracycline in patients presenting with dyspepsia at the Kenyatta National Hospital. DESIGN Cross-sectional descriptive study. SETTING Kenyatta National Hospital, Nairobi. SUBJECTS Two hundred and sixty-seven patients aged 15 to 85 years, presenting with dyspepsia and referred for upper gastro-intestinal endoscopy were recruited into the study. RESULTS Between October 2003 and April 2004, 138 male and 129 female patients aged 15-85 years, with a mean age of 45.4 years were studied. Gastritis was the most common endoscopic finding, occurring in 55%, followed by normal-looking mucosa in 27% and peptic ulcer disease in 16% of the patients. The rapid urease test was positive in 184 patients (69%). The culture yield was 62% of these CLO (Campylobacter like organisms) positive biopsies. The MIC90 (minimum inhibitory concentration) was 256 mg/l for metronidazole, 1.5 mg/l for clarithromycin, 1.5 mg/l for tetracycline and 0.75 mg/l for amoxicillin. The MIC values for amoxicillin were significantly higher in the female patients (p = 0.02) but showed no significant variation for age. The MIC values for metronidazole, tetracycline and clarithromycin showed no significant difference for age or gender. MIC values for tetracycline were significantly higher for patients with duodenitis and duodenal ulcer p = 0.009 and 0.02, respectively. CONCLUSION All isolated H. pylori organisms were resistant to metronidazole. The susceptibility of the H. pylori isolates was 93.6% for clarithromycin, 95.4% for amoxicillin and 98.1% for tetracycline. The MIC90 for amoxicillin and clarithromycin were found to be close to the upper limit of the susceptibility range. There was a rising MIC90 for tetracycline and metronidazole compared to that found in a previous study in 1991.
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Affiliation(s)
- L Lwai-Lume
- Departmnent of Medicine, College of Health Sciences, University of Nairobi, P.O. Box 19676, Nairobi, Kenya
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Takala SL, Escalante AA, Branch OH, Kariuki S, Biswas S, Chaiyaroj SC, Lal AA. Genetic diversity in the Block 2 region of the merozoite surface protein 1 (MSP-1) of Plasmodium falciparum: additional complexity and selection and convergence in fragment size polymorphism. Infect Genet Evol 2006; 6:417-24. [PMID: 16517218 PMCID: PMC1853307 DOI: 10.1016/j.meegid.2006.01.009] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2006] [Accepted: 01/31/2006] [Indexed: 10/24/2022]
Abstract
Fragment size in the Block 2 repetitive region of merozoite surface protein 1 (MSP1) has commonly been used as a molecular marker in studies of malaria transmission dynamics and host immunity in Plasmodium falciparum malaria. In this study, we further explore the genetic variation in MSP-1 Block 2 underlying potential problems faced while studying the immune responses elicited by this vaccine target and while using it as a molecular marker in epidemiologic investigations. We describe the distribution of a new Block 2 recombinant allele family in samples collected from western Kenya and other malarious regions of the world and provide evidence that this allele family is found worldwide and that all MR alleles most likely originated from a single recombination event. We test whether the number of tandem repeats (i.e. fragment size) can be considered neutral in an area of high transmission in western Kenya. In addition, we investigate the validity of the assumption that Block 2 alleles of the same size and allele family are identical by examining MSP1 Block 2 amino acid sequences obtained from full-length MSP-1 clones generated from infected Kenyan children and find that this assumption does not hold. We conclude that the worldwide presence of a new allele family, the effect of positive natural selection, and the lack of conserved amino acid motifs within alleles of the same size suggest a higher level of complexity that may hamper our ability to elucidate allele family specific immune responses elicited by this vaccine target and its overall use as genetic marker in other types of epidemiologic investigations.
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Affiliation(s)
- S L Takala
- Division of Parasitic Diseases, National Center for Infectious Diseases, Centers for Disease Control and Prevention, GA, USA.
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Nys S, Okeke IN, Kariuki S, Dinant GJ, Driessen C, Stobberingh EE. Antibiotic resistance of faecal Escherichia coli from healthy volunteers from eight developing countries. J Antimicrob Chemother 2004; 54:952-5. [PMID: 15471998 DOI: 10.1093/jac/dkh448] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVES To determine the prevalence of antibiotic-resistant faecal Escherichia coli from adult volunteers from urban (U) areas in Kenya, Mexico, Peru and the Philippines, and non-urban (NU) locations in Curacao, Mexico, Venezuela, Ghana, Zimbabwe and the Philippines. METHODS Faecal samples of adult volunteers (n=1290) were analysed in one laboratory for the presence of antimicrobial-resistant E. coli using Eosin Methylene Blue agar plates containing, respectively, ampicillin, oxytetracycline, cefazolin, ciprofloxacin, gentamicin, chloramphenicol and trimethoprim at breakpoint concentrations. RESULTS The mean age of the volunteers was approximately 35 years; most of them were female. Ciprofloxacin resistance was in the range 1%-63%: the highest percentages were found in the urban populations of Asia and South America. In Peru and the Philippines (U and NU), the prevalence of gentamicin resistance was >20%. Cefazolin resistance was the highest in the urban Philippines (25%). Higher prevalences for ampicillin, oxytetracycline and trimethoprim were found for urban areas compared with non-urban ones of Asia, Africa and South America, respectively (P<0.05). CONCLUSIONS In the populations studied, antibiotic resistance in faecal E. coli from adult volunteers was emerging for cefazolin, gentamicin and ciprofloxacin and was high for the older drugs ampicillin, oxytetracycline, trimethoprim and chloramphenicol.
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Affiliation(s)
- S Nys
- Department of Medical Microbiology, University Hospital Maastricht, Medical Microbiology, P.O. Box 5800, 6202AZ Maastricht, The Netherlands
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Kariuki S, Muyodi J, Mirza B, Mwatu W, Daniels JJD. Antimicrobial susceptibility in community-acquired bacterial pneumonia in adults. East Afr Med J 2003; 80:213-7. [PMID: 12918806 DOI: 10.4314/eamj.v80i4.8645] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
OBJECTIVES To determine the antimicrobial susceptibility patterns of Streptococcus pneumoniae and Haemophilus influenzae, two bacterial pathogens commonly associated with community-acquired pneumonia. DESIGN Cross-sectional study. SETTING Bacterial isolates were obtained from adults suspected to have community-acquired pneumonia and who sought treatment at two city council clinics in Nairobi, Kenya. Susceptibility to antimicrobial agents was performed using a microdilution broth method, according to the criteria set by the National Committee for Clinical Laboratory Standards. RESULTS A total of 277 S. pneumoniae and 58 H. influenzae were obtained from 536 adults examined in the period January 1998 to December 1999. Of the 277 S. pneumoniae, only 56.7% were susceptible to penicillin and 7.6% of strains were resistant to two or more antimicrobial agents. Of the 58 H. influenzae strains, 91.4% were sensitive to ampicillin, with 6.8% resistant to two or more antimicrobial agents. 8.6% were beta-lactamase producers and accounted for the entire ampicillin-resistant population. CONCLUSION The prevalence of resistance to penicillin and other commonly used antibiotics among pneumococci is high and the large number of multi-resistant strains among H. influenzae is a cause for concern. The prudent use of antibiotics in treatment of pneumonia and other infections should be advocated to minimise spread of resistance.
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Affiliation(s)
- S Kariuki
- Centre for Microbiology Research, Kenya Medical Research Institute, PO Box 43640, Nairobi, Kenya
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Oundo JO, Muli F, Kariuki S, Waiyaki PG, Iijima Y, Berkley J, Kokwaro GO, Ngetsa CJ, Mwarumba S, Torto R, Lowe B. Non-typhi salmonella in children with severe malaria. East Afr Med J 2002; 79:633-9. [PMID: 12678446 DOI: 10.4314/eamj.v79i12.8670] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
OBJECTIVE To determine the association between Plasmodium falciparum malaria and non-typhi Salmonella in children. DESIGN Cross-sectional hospital based study. SETTING Kilifi District Hospital (KDH) between January 1997 and June 2001. SUBJECTS Children aged between three months to 123 months (mean age 28.28 months) and who had been admitted to the paediatric or High Dependency Research Ward (HDRW) of the KDH. METHODS A total of 19, 118 blood cultures routinely obtained for all admissions and 1,820 clinically indicated stools samples were obtained from 9,147 children admitted with malaria. The specimens were cultured and antibiotic sensitivity done using standard laboratory procedures with stringent internal and external quality control in place. RESULTS The total bacterial pathogens isolated from blood and stool were 1,395/19,118 (7.3%) and 342/1,820 (19%) respectively. Non-typhi salmonella consisted of 260/1,395 (18.6%) of the positive blood cultures and 92/324 (28.4%) of the stool cultures out of which a total of 101 NTS occurred in children with severe malaria. Out of the 9,147 malaria cases admitted, 101/9,147 (1.10%) had concomitant NTS infection. NTS with severe malaria as a proportion of all malaria admissions for the period varied between 0.8% and 1.5%. There was a significant association (p-value=0.032) between clinical outcome of death and female sex of the patient. The NTS isolates which occurred with severe malaria showed various levels of antibiotic resistance. They were resistant to ampicillin (35%), chloramphenicol (18%), gentamicin (22%), cefuroxime (29%), sulphamethoxazole-trimethoprim (39%), ciprofloxacin (3%), cefotaxime (14%), amoxycillin-clavulanic acid (26%) and tobramycin (18.0%). Multidrug resistance (MDR) was seen in 34 (33.6%) of the isolates. CONCLUSIONS NTS and severe malaria occurring together are a problem in this area and that a large number of the isolates are MDR. An elaborate case-controlled study is required to elucidate the chain of events of both NTS and malaria parasite co-existence.
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Affiliation(s)
- J O Oundo
- Centre for Microbiology Research, Kenya Medical Research Institute, Nairobi, Kenya
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Abstract
DNA-DNA hybridization, cultured cell lines, and transmission electron microscopy were used to study pathogenicity traits of 64 Escherichia coli isolated from apparently healthy chickens from 18 small-scale farms in Thika District, Kenya. A total of 39 (60.9%) isolates hybridized with the eae gene probe for enteropathogenic E. coli (EPEC) whereas another 16 (25%) hybridized with the lt and st gene probes and were categorized as enterotoxigenic E. coli. Electron microscopic examination of the eae probe-positive E. coli cultures with the HT-2919A cell line confirmed that they were able to attach intimately and produced effacement typical of EPEC. In addition, negative stain electron microscopy showed that the EPEC strains produced pili that have previously been associated with increased virulence of E. coli infections in chickens. This study has also demonstrated that apparently healthy chickens may carry enteropathogenic E. coli strains.
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Affiliation(s)
- S Kariuki
- Department of Medical Microbiology and Genito-Urinary Medicine, University of Liverpool, United Kingdom
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Guinness L, Arthur G, Bhatt SM, Achiya G, Kariuki S, Gilks CF. Costs of hospital care for HIV-positive and HIV-negative patients at Kenyatta National Hospital, Nairobi, Kenya. AIDS 2002; 16:901-8. [PMID: 11919492 DOI: 10.1097/00002030-200204120-00010] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To record the costs of hospital care for HIV-positive and -negative patients in Nairobi, and identify costs paid by patients per admission. DESIGN Cost data were collected on inpatients enrolled in a linked clinical study using standardized costing methods. SETTING Kenyatta National Hospital, Nairobi's main district hospital. PATIENTS Consecutive adult medical admissions to one ward over 14 weeks who consented to enrollment; tertiary referrals were excluded. MAIN OUTCOME MEASURE Average length of stay and cost per patient admission. RESULTS The hospital costs of 398 patients (163 HIV positive; 33 with clinical AIDS) were analysed. The mean length of stay was 9.3 days and the mean cost per patient admission was US$163. There was no significant difference in costs or mean lengths of stay between HIV-positive and -negative groups, nor were the costs and lengths of stay for clinical AIDS patients significantly different to those for HIV-positive patients without AIDS. The patient charges paid to the hospital per admission, recorded for 344 patients, were on average US$61; and did not differ by HIV status. CONCLUSION The similar cost patterns for inpatient care irrespective of HIV status or clinical AIDS probably reflects the limited provision of care beyond basic clinical services. Length of stay rather than differing treatment regimes thus appears to be the main cost driver. Private costs of medical care were high and were likely to pressurize households. When resources are limited, the introduction of new, more costly therapies needs careful planning. The study provides cost information for planning care services in resource-poor settings.
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Affiliation(s)
- Lorna Guinness
- Liverpool School of Tropical Medicine, Liverpool, L3 5QA UK
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Zhou Z, Xiao L, Branch OH, Kariuki S, Nahlen BL, Lal AA. Antibody responses to repetitive epitopes of the circumsporozoite protein, liver stage antigen-1, and merozoite surface protein-2 in infants residing in a Plasmodium falciparum-hyperendemic area of western Kenya. XIII. Asembo Bay Cohort Project. Am J Trop Med Hyg 2002; 66:7-12. [PMID: 12135271 DOI: 10.4269/ajtmh.2002.66.7] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
The present study was initiated to characterize antibody responses to repetitive epitopes of the circumsporozoite protein (CSP), liver stage antigen-1 (LSA-1), and merozoite surface protein-2 (MSP-2) of Plasmodium falciparum in infants residing in a P. falciparum-hyperendemic area of western Kenya. In this study, development and maintenance of these antibody responses in 28 infants were studied longitudinally by use of monthly serum samples collected from birth to age 1 year. Mother plasma and infant umbilical cord plasma were also tested to assess the transplacental transfer of maternal antibodies. Results showed that antibodies passively transferred from mothers were detectable for CSP, LSA-1, and MSP-2 repeat epitopes. Infants were able to mount and maintain a strong antibody response against LSA-1 in their first year of life. Infants often responded to CSP repeats, but with a much lower antibody titer. Antibody responses in infants against Fc27 and 3D7 repeats of MSP-2 were low throughout their first year. In addition, 51 infants whose first detected infection occurred at > 4 months of age were selected to determine antibody responses to the antigens tested upon their first and second detected infections. Antibody responses to LSA-1 and, to a lesser degree, CSP increased in positivity rates and titer upon second infection. Antibody responses to Fc27-type and 3D7-type repeats of MSP-2 were low upon both infections. There was no association between maternally transferred anti-LSA-1, anti-CSP, or anti-MSP-2 antibodies and an infant's first detected infection. No significant correlation was found between an infant's antibody responses to the 4 antigen repetitive epitopes and protection against malarial parasitemia during the first year of life.
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Affiliation(s)
- Z Zhou
- Division of Parasitic Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia 30341, USA
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Branch OH, Takala S, Kariuki S, Nahlen BL, Kolczak M, Hawley W, Lal AA. Plasmodium falciparum genotypes, low complexity of infection, and resistance to subsequent malaria in participants in the Asembo Bay Cohort Project. Infect Immun 2001; 69:7783-92. [PMID: 11705960 PMCID: PMC98874 DOI: 10.1128/iai.69.12.7783-7792.2001] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
To assess the relationship between the within-host diversity of malaria infections and the susceptibility of the host to subsequent infection, we genotyped 60 children's successive infections from birth through 3 years of life. MSP-1 Block2 genotypes were used to estimate the complexity of infection (COI). Malaria transmission and age were positively associated with the number of K1 and Mad20 alleles detected (COI(KM)) (P < 0.003). Controlling for previous parasitemia, transmission, drug treatment, parasite density, sickle cell, and age, COI(KM) was negatively correlated with resistance to parasitemia of > 500/microl (P < 0.0001). Parasitemias with the RO-genotype were more resistant than those without this genotype (P < 0.0000). The resistance in low COI(KM) infections was not genotype specific. We discuss the impact of genotype-transcending immunity to conserved antigenic determinants. We also propose a diversity-driven immunomodulation hypothesis that may explain the delayed development of natural immunity in the first few years of life and suggest that interventions that decrease the COI(KM) could facilitate the development of protective immunity.
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Affiliation(s)
- O H Branch
- Division of Parasitic Diseases, National Center for Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
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Abstract
OBJECTIVE To determine if antimicrobial resistance occurs in various bacterial species isolated from rats. METHOD Two hundred and fifteen rats were trapped from areas in and around Nairobi, Kenya. They were sacrificed and their intestinal, liver and spleen specimens obtained. Various bacterial species were isolated from these specimens. The species were analysed for antimicrobial susceptibility to 12 commonly used antimicrobials using the disc diffusion technique. RESULTS The bacterial species isolated included pathogenic and potentially pathogenic ones such as Escherichia coli 137, Salmonella typhimurium 1, Klebsiella pneumoniae 2, Enterobacter cloacae 4, Enterobacter sakazakii 2, Citrobacter freundii 3, Morganella morganii (2), Pseudomonas aeruginosa 2 and Burkhoddria cepacia 6. Depending on the species, the resistance to the various antimicrobials were: 0-100% for cefotaxime, nalidixic acid, cefuroxime, tetracycline, chloramphenicol, co-amoxyclav, sulfamethoxazole, ampicillin, trimethoprim and cephradine, 0-66.6% for gentamicin and 0-25% for apramycin. CONCLUSION The results showed that, rats from the study area harboured bacterial species with antimicrobial resistance. These micro-organisms may form an important reservoir for antibiotic resistance which could pose a public health hazard. Control of rat populations, better management of sewer systems and waste dumping sites are recommended in order to reduce occurrence of these drug resistance reservoirs.
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Affiliation(s)
- F M Gakuya
- Department of Public Health, Pharmacology and Toxicology, University of Nairobi, Kenya
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Abstract
OBJECTIVES To determine if antimicrobial resistance occurs in E. coli isolated from rats and if this resistance is transferable via plasmids. METHODS Sixty Escherichia coli isolates obtained from 215 rats trapped in and around Nairobi, Kenya, were analysed for antimicrobial susceptibility to eleven commonly used antimicrobials. Plasmid DNA analysis and in-vitro conjugation tests were conducted on twenty two resistant isolates. RESULTS A total of 12 (20%) E. coli were resistant to at least one of the commonly used drugs including ampicillin, sulphamethoxazole and streptomycin. Eight (13.3%) isolates were multidrug resistant. The drug resistant E. coli fell into five plasmid profile groups with plasmids ranging between two and 98 megadaltons (Mda). Resistance to ampicillin was transferable. CONCLUSION The results of this study show that rats from the study area may form an important reservoir for drug-resistant E. coli that could pose a public health hazard.
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Affiliation(s)
- F M Gakuya
- Department of Public Health, Pharmacology and Toxicology, University of Nairobi, P.O. Box 29053, Nairobi
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Abstract
Antibiotics have been considered to be safe and effective 'magic bullets', with no disadvantages to their widespread use. This has been proven to be a complacent attitude, with ever-increasing prevalences of resistance now evident. The present review covers aspects of the development, mechanisms and genetics of antimicrobial resistance in enteric commensals and pathogens.
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Affiliation(s)
- S Kariuki
- Centre for Microbiology Research, Kenya Medical Research Institute, Nairobi, Kenya
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Kokwaro G, Kariuki S. Medical research in Africa: problems and some solutions. Malawi Med J 2001; 13:40. [PMID: 27528905 PMCID: PMC3345382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023] Open
Abstract
This article appeared in the Bulletin of the Royal Society of Tropical Medicine and Hygiene, UK, and is reproduced with kind permission of the authors.
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Affiliation(s)
- G Kokwaro
- Wellcome Trust Research Laboratories
| | - S Kariuki
- Centre for Microbiology Research, Kenya Medical Research Institute (KEMRI), P O Box 43640, Nairobi, Kenya
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Udhayakumar V, Kariuki S, Kolczack M, Girma M, Roberts JM, Oloo AJ, Nahlen BL, Lal AA. Longitudinal study of natural immune responses to the Plasmodium falciparum apical membrane antigen (AMA-1) in a holoendemic region of malaria in western Kenya: Asembo Bay Cohort Project VIII. Am J Trop Med Hyg 2001; 65:100-7. [PMID: 11508382 DOI: 10.4269/ajtmh.2001.65.100] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
We investigated the development and maintenance of proliferative and antibody responses to apical membrane antigen-1 (AMA-1) epitopes in a holoendemic area of western Kenya. Young children (< 10 years), older children (10-17 years), and adults (> or = 18 years) were followed longitudinally for antibody and T-cell responses at 3 time points with an interval of 3-4 months. The proliferative responses against the AMA-1 T epitopes (PL171, PL172, PL173, PL186, PL191, and PL192) were not stable during follow-up; however, response to mycobacterial antigen PPD was highly stable. The responder frequencies were similar in all 3 time points except for epitope PL192. The younger and older children responded more frequently to T-cell epitopes, but the differences were not significant. A positive proliferative response to PL191 was associated with a significantly lower risk of parasitemia at subsequent follow-up (relative risk, 0.5; P = 0.03). The presence of antibody response to B epitopes PL169, PL170, PL173, PL187, and PL192 in one time point was associated with a subsequent response (P = 0.0001-0.008) suggesting a stable response. Younger (P = 0.046) and older children (P = 0.017) more frequently responded to epitope PL169 than did adults, and adults responded more frequently to PL187 than did younger children (P = 0.009). Responses to AMA-1 T-cell epitopes were short lived, and antibody responses were relatively stable.
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Affiliation(s)
- V Udhayakumar
- Division of Parasitic Diseases, National Center for Infectious Diseases, Centers for Disease Control and Prevention, Public Health Service, U.S. Department of Health and Human Services, Atlanta, Georgia, USA.
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Kariuki S, Corkill JE, Revathi G, Musoke R, Hart CA. Molecular characterization of a novel plasmid-encoded cefotaximase (CTX-M-12) found in clinical Klebsiella pneumoniae isolates from Kenya. Antimicrob Agents Chemother 2001; 45:2141-3. [PMID: 11408239 PMCID: PMC90616 DOI: 10.1128/aac.45.7.2141-2143.2001] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Nine Klebsiella pneumoniae isolates, six from blood and three from cerebrospinal fluid of newborn babies at Kenyatta National Hospital, Nairobi, Kenya, were analyzed for the mechanism of cephalosporin resistance. By using pulsed-field gel electrophoresis of XbaI-digested chromosomal DNA, all the nine isolates were found to be clonal. PCR and direct sequencing revealed a novel extended-spectrum beta-lactamase, which we designated CTX-M-12. It has a more potent hydrolytic activity against cefotaxime than against ceftazidime and a pI of 9.0 and is encoded on a large self-transferable ca. 160-kbp plasmid.
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Affiliation(s)
- S Kariuki
- Centre for Microbiology Research, Kenya Medical Research Institute, Nairobi, Kenya.
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Shi YP, Nahlen BL, Kariuki S, Urdahl KB, McElroy PD, Roberts JM, Lal AA. Fcgamma receptor IIa (CD32) polymorphism is associated with protection of infants against high-density Plasmodium falciparum infection. VII. Asembo Bay Cohort Project. J Infect Dis 2001; 184:107-11. [PMID: 11398118 DOI: 10.1086/320999] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2000] [Revised: 04/03/2001] [Indexed: 11/03/2022] Open
Abstract
In vitro studies have shown that inhibition of Plasmodium falciparum blood-stage parasite growth by antibody-dependent cellular inhibition is mediated by cooperation between malaria-specific IgG1 and IgG3, but not IgG2, and monocytes via the Fcgamma receptor II (FcgammaRII). A single amino acid substitution at position 131 in FcgammaRIIa is critical in the binding of human IgG subclasses. The hypothesis that the FcgammaRIIa-Arg/Arg131 genotype, which does not bind to IgG2, is a host genetic factor for protection against high-density P. falciparum infection was tested. One hundred eighty-two infants from a large community-based birth cohort study in western Kenya were selected for an unmatched case-control study. Results showed that the infants with the FcgammaRIIa-Arg/Arg131 genotype were significantly less likely to be at risk for high-density falciparum infection, compared with infants with the FcgammaRIIa-His/Arg131 genotype (adjusted odds ratio, 0.278; 95% confidence interval, 0.123-0.627; P=.0021). This finding supports the hypothesis.
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Affiliation(s)
- Y P Shi
- Division of Parasitic Diseases, National Centers for Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, USA.
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Kariuki S, Oundo JO, Muyodi J, Lowe B, Threlfall EJ, Hart CA. Genotypes of multidrug-resistant Salmonella enterica serotype typhimurium from two regions of Kenya. FEMS Immunol Med Microbiol 2000; 29:9-13. [PMID: 10967254 DOI: 10.1111/j.1574-695x.2000.tb01498.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A combination of phage typing and pulsed-field gel electrophoresis of Xbal-digested chromosomal DNA has been used to study the epidemiological relationships of multidrug-resistant Salmonella enterica serotype typhimurium from Nairobi (64 isolates) and Kilifi (40 isolates) collected over the period 1994-1997. Isolates from Nairobi belonged to 11 definitive phage types (DTs) encompassing eight different PFGE patterns. In contrast, isolates from Kilifi were mainly DT 56 (60%) and all fell into a single PFGE pattern. The remaining isolates did not conform to a recognisable phage type. We conclude that multidrug-resistant S. typhimurium infections from Nairobi were caused by multiple strains while those from Kilifi were likely to be from a microepidemic caused by a single clone.
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Affiliation(s)
- S Kariuki
- Centre for Microbiology Research, Kenya Medical Research Institute, Nairobi.
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