Biomed Full Text Articleshttp://erepository.uonbi.ac.ke/handle/11295/145502024-03-29T08:06:39Z2024-03-29T08:06:39ZHigh Multiple Carriage and Emergence of Streptococcus Pneumoniae Vaccine Serotype Variants in Malawian ChildrenKamng’ona, Arox WHinds, JasonBar-zeev, NaorGould, Katherine AChaguza, ChrispinMsefula, ChisomoCornick, Jennifer EKulohoma, KulohomaGray, KatherineBentley, Stephen DEverett, Heyderman & Dean BFrench, NeilHeyderman, Robert SEverett, Dean Bhttp://erepository.uonbi.ac.ke/handle/11295/1636372023-05-22T07:24:22Z2015-01-01T00:00:00ZHigh Multiple Carriage and Emergence of Streptococcus Pneumoniae Vaccine Serotype Variants in Malawian Children
Kamng’ona, Arox W; Hinds, Jason; Bar-zeev, Naor; Gould, Katherine A; Chaguza, Chrispin; Msefula, Chisomo; Cornick, Jennifer E; Kulohoma, Kulohoma; Gray, Katherine; Bentley, Stephen D; Everett, Heyderman & Dean B; French, Neil; Heyderman, Robert S; Everett, Dean B
Background: Carriage of either single or multiple pneumococcal serotypes (multiple carriage) is a prerequisite for
developing invasive pneumococcal disease. However, despite the reported high rates of pneumococcal carriage in
Malawi, no data on carriage of multiple serotypes has been reported previously. Our study provides the first description
of the prevalence of multiple pneumococcal carriage in Malawi.
Methods: The study was conducted in Blantyre and Karonga districts in Malawi, from 2008 to 2012. We recruited 116
children aged 0–13 years. These children were either HIV-infected (N = 44) or uninfected (N = 72). Nasopharyngeal
samples were collected using sterile swabs. Pneumococcal serotypes in the samples were identified by microarray.
Strains that could not be typed by microarray were sequenced to characterise possible genetic alterations within the
capsular polysaccharide (CPS) locus.
Results: The microarray identified 179 pneumococcal strains (from 116 subjects), encompassing 43 distinct serotypes
and non-typeable (NT) strains. Forty per cent (46/116) of children carried multiple serotypes. Carriage of vaccine type
(VT) strains was higher (p = 0.028) in younger (0–2 years) children (71 %, 40/56) compared to older (3–13 years) children
(50 %, 30/60). Genetic variations within the CPS locus of known serotypes were observed in 19 % (34/179) of the strains
identified. The variants included 13-valent pneumococcal conjugate vaccine (PCV13) serotypes 6B and 19A, and the
polysaccharide vaccine serotype 20. Serotype 6B variants were the most frequently isolated (47 %, 16/34). Unlike the
wild type, the CPS locus of the 6B variants contained an insertion of the licD-family phosphotransferase gene. The CPS
locus of 19A- and 20-variants contained an inversion in the sugar-biosynthesis (rmlD) gene and a 717 bp deletion within
the transferase (whaF) gene, respectively.
Conclusions: The high multiple carriage in Malawian children provides opportunities for genetic exchange through
horizontal gene transfer. This may potentially lead to CPS locus variants and vaccine escape. Variants reported here
occurred naturally, however, PCV13 introduction could exacerbate the CPS genetic variations. Further studies are
therefore recommended to assess the invasive potential of these variants and establish whether PCV13 would offer
cross-protection. We have shown that younger children (0–2 years) are a reservoir of VT serotypes, which makes them
an ideal target for vaccination.
2015-01-01T00:00:00ZComment on “Encephalopathy in patients with COVID‐19: A review”Cheruiyot, Ihttp://erepository.uonbi.ac.ke/handle/11295/1535842021-01-08T07:42:53Z2020-06-30T00:00:00ZComment on “Encephalopathy in patients with COVID‐19: A review”
Cheruiyot, I
2020-06-30T00:00:00ZResponding to maternal, neonatal and child health equipment needs in Kenya: a model for an innovation ecosystem leveraging on collaborations and partnershipsAyah, ROng'ech, J.Mbugua, E. M.Kosgei, R. C.Waller, K.Gathara, Dhttp://erepository.uonbi.ac.ke/handle/11295/1535832021-01-08T07:18:34Z2020-04-24T00:00:00ZResponding to maternal, neonatal and child health equipment needs in Kenya: a model for an innovation ecosystem leveraging on collaborations and partnerships
Ayah, R; Ong'ech, J.; Mbugua, E. M.; Kosgei, R. C.; Waller, K.; Gathara, D
Background
Up to 70% of medical devices in low-income and middle-income countries are partially or completely non-functional, impairing service provision and patient outcomes. In Sub-Saharan Africa, medical devices not designed for local conditions, lack of well-trained biomedical engineers and diverse donated equipment have led to poor maintenance and non-repair. The Maker Project’s aim was to test the effectiveness of an innovative partnership ecosystem network, the ‘Maker Hub’, in reducing gaps in the supply of essential medical devices for maternal, newborn and child health. This paper describes the first phase of the project, the building of the Maker Hub.
Methods
Key activities in setting up the Maker Hub—a collaborative partnership between the University of Nairobi (UoN) and the Kenyatta National Hospital (KNH), catalysed by Concern Worldwide Kenya—are described using a product development partnership approach. Using a health systems approach, a needs assessment identified a medical equipment shortlist. Design thinking with a capacity building component was used by the UoN (innovators, public health specialists, engineers) working closely and with KNH nurses, physicians and biomedical engineers to develop the prototypes.
Results
To date, four medical device prototypes have been developed. Two have been evaluated by the National Bureau of Standards and one has undergone clinical testing.
Conclusions
We have demonstrated an innovative partnership ecosystem that has developed medical devices that have undergone national standards evaluation and clinical testing, a first in Sub-Saharan Africa. Promoting a robust innovation ecosystem for medical equipment requires investment in building trust in the innovation ecosystem.
2020-04-24T00:00:00ZMolecular prevalence of emerging Anaplasma and Ehrlichia pathogens in apparently healthy dairy cattle in peri-urban Nairobi, KenyaPeter, S. GAboge, G. OKariuki, H. WKanduma, E. G.Gakuya, D. W.Maingi, N.Mainga, A. Ohttp://erepository.uonbi.ac.ke/handle/11295/1535812021-01-08T06:38:49Z2020-09-29T00:00:00ZMolecular prevalence of emerging Anaplasma and Ehrlichia pathogens in apparently healthy dairy cattle in peri-urban Nairobi, Kenya
Peter, S. G; Aboge, G. O; Kariuki, H. W; Kanduma, E. G.; Gakuya, D. W.; Maingi, N.; Mainga, A. O
Background
Anaplasma and Ehrlichia species are tick-borne pathogens of both veterinary and public health importance. The current status of these pathogens, including emerging species such as Ehrlichia minasensis and Anaplasma platys, infecting cattle in Kenya, remain unclear, mainly because of limitation in the diagnostic techniques. Therefore, we investigated the Anaplasma and Ehrlichia species infecting dairy cattle in Nairobi, Kenya using molecular methods.
Results
A total of 306 whole blood samples were collected from apparently healthy dairy cattle. Whole blood DNA was extracted and tested for presence of Anaplasma and Ehrlichia DNA through amplification and sequencing of the 16S rDNA gene. Sequence identity was confirmed using BLASTn analysis while phylogenetic reconstruction was performed to determine the genetic relationship between the Kenyan isolates and other annotated genotypes available in GenBank. Anaplasma and Ehrlichia species were detected in 19.9 and 3.3% of all the samples analyzed, respectively. BLASTn analysis of the sequences against non-redundant GenBank nucleotide database revealed infections with A. platys (44.8%), A. marginale (31%) and A. bovis (13.8%). All four sequenced Ehrlichia spp. were similar to Ehrlichia minasensis. Nucleotide polymorphism was observed for A. platys, A. bovis and E. minasensis. The Anaplasma species clustered in four distinct phylogenetic clades including A. marginale, A. platys, A. bovis and some unidentified Anaplasma spp. The Kenyan Ehrlichia minasensis clustered in the same clade with isolates from America and Australia but distant from E. ruminantium.
Conclusion
This study provides the first report of infection of dairy cattle in Kenya with A. platys and E. minasensis, which are emerging pathogens. We conclude that cattle in peri-urban Nairobi are infected with various species of Anaplasma and E. minasensis. To understand the extent of these infections in other parts of the country, large-scale screening studies as well as vector identification is necessary to inform strategic control.
2020-09-29T00:00:00Z