Weed species in tomato production and their role as alternate hosts of 'Tomato spotted wilt virus' and its vector 'Frankliniella occidentalis'

'Tomato spotted wilt virus' (TSWV) is an important plant virus that infects a wide range of hosts including weeds making its management difficult. A survey was undertaken to establish the occurrence of weed species in tomato production systems in Kenya and their role as hosts of TSWV and its vectors. Selected weed species were further evaluated for their reaction to TSWV, transmission efficiency by 'Frankliniella occidentalis' and ability to support thrips reproduction. Of the 43 weed species identified in the field, 29 species had been reported as hosts of TSWV, twowere non-hosts and 11 had no record of their status. Among the more common species, 'Amaranthus hybridus', 'Solanum nigrum', 'Tagetes minuta' and 'Datura stramonium' were susceptible to the virus and supported high levels of thrips reproduction. The TSWV could not be transmitted to 'Galinsoga parviflora' and 'Sonchus oleraceus' by 'F. occidentalis' despite them being highly susceptible in mechanical transmission tests. There was a significant correlation between feeding damage and number of larvae of 'F. occidentalis' on different weeds. Occurrence of weeds that support thrips reproduction and are good hosts of TSWV is a clear indicator of their role in epidemiology and the importance of their management for disease control

Effect of provision of an integrated neonatal survival kit and early cognitive stimulation package by community health workers on developmental outcomes of infants in Kwale County, Kenya: study protocol for a cluster randomized trial

Background: Each year, more than 200 million children under the age of 5 years, almost all in low- and middle-income countries (LMICs), fail to achieve their developmental potential. Risk factors for compromised development often coexist and include inadequate cognitive stimulation, poverty, nutritional deficiencies, infection and complications of being born low birthweight and/or premature. Moreover, many of these risk factors are closely associated with newborn morbidity and mortality. As compromised development has significant implications on human capital, inexpensive and scalable interventions are urgently needed to promote neurodevelopment and reduce risk factors for impaired development. Method/Design: This cluster randomized trial aims at evaluating the impact of volunteer community health workers delivering either an integrated neonatal survival kit, an early stimulation package, or a combination of both interventions, to pregnant women during their third trimester of pregnancy, compared to the current standard of care in Kwale County, Kenya. The neonatal survival kit comprises a clean delivery kit (sterile blade, cord clamp, clean plastic sheet, surgical gloves and hand soap), sunflower oil emollient, chlorhexidine, ThermoSpotTM, Mylar infant sleeve, and a reusable instant heater. Community health workers are also equipped with a portable hand-held electric scale. The early cognitive stimulation package focuses on enhancing caregiver practices by teaching caregivers three key messages that comprise combining a gentle touch with making eye contact and talking to children, responsive feeding and caregiving, and singing. The primary outcome measure is child development at 12 months of age assessed with the Protocol for Child Monitoring (Infant and Toddler version). The main secondary outcome is newborn mortality. Discussion: This study will provide evidence on effectiveness of delivering an innovative neonatal survival kit and/or early stimulation package to pregnant women in Kwale County, Kenya. Study findings will help inform policy on the most appropriate interventions for promoting healthy brain development and reduction of newborn morbidity and mortality in Kenya and other similar settings. Trial registration: ClinicalTrial.gov NCT02208960 (August 1, 2014

Metagenomic analyses and genetic diversity of Tomato leaf curl Arusha virus affecting tomato plants in Kenya.

Funder: Bill and Melinda Gates Foundation; doi: http://dx.doi.org/10.13039/100000865BACKGROUND: Tomato production is threatened worldwide by the occurrence of begomoviruses which are associated with tomato leaf curl diseases. There is little information on the molecular properties of tomato begomoviruses in Kenya, hence we investigated the population and genetic diversity of begomoviruses associated with tomato leaf curl in Kenya. METHODS: Tomato leaf samples with virus-like symptoms were obtained from farmers' field across the country in 2018 and Illumina sequencing undertaken to determine the genetic diversity of associated begomoviruses. Additionally, the occurrence of selection pressure and recombinant isolates within the population were also evaluated. RESULTS: Twelve complete begomovirus genomes were obtained from our samples with an average coverage of 99.9%. The sequences showed 95.7-99.7% identity among each other and 95.9-98.9% similarities with a Tomato leaf curl virus Arusha virus (ToLCArV) isolate from Tanzania. Analysis of amino acid sequences showed the highest identities in the regions coding for the coat protein gene (98.5-100%) within the isolates, and 97.1-100% identity with the C4 gene of ToLCArV. Phylogenetic algorithms clustered all Kenyan isolates in the same clades with ToLCArV, thus confirming the isolates to be a variant of the virus. There was no evidence of recombination within our isolates. Estimation of selection pressure within the virus population revealed the occurrence of negative or purifying selection in five out of the six coding regions of the sequences. CONCLUSIONS: The begomovirus associated with tomato leaf curl diseases of tomato in Kenya is a variant of ToLCArV, possibly originating from Tanzania. There is low genetic diversity within the virus population and this information is useful in the development of appropriate management strategies for the disease in the country

Single intraoperative intravenous Co-Amoxiclav versus postoperative full oral course in prevention of postadenotonsillectomy morbidity: a randomised clinical trial

<p>Abstract</p> <p>Background</p> <p>Adenotonsillectomy results in postoperative morbidity which otolaryngologists attempt to reduce by use of antibiotics. The regimes used as quite varied with some opting for a full oral course postoperatively while others prefer prophylactic doses. This randomised clinical trial done in Kenyatta National Hospital, Kenya had the aim of comparing the efficacy of Co-Amoxiclav given as a single intravenous dose with a full oral course in the prevention of post adenotonsillectomy morbidity.</p> <p>Methods</p> <p>126 patients below 12 years scheduled to undergo adenotonsillectomy were randomised into two groups. 63 were given a single intravenous dose of Enhancin [Co-Amoxiclav] at induction while the remaining half received a five days oral course of the same postoperatively. All received oral Pacimol [Paracetamol] in the postoperative period. Analysis was done and comparison made between the two groups with regards to pain, fever and diet tolerated in the postoperative period with a follow up period of seven days.</p> <p>Results</p> <p>There was no statistical significant difference between the two groups with regards to postoperative pain, fever and diet tolerated. All had a P-value > 0.2. Postoperative pain was highest in the first postoperative day and reduced progressively to the lowest level on the 7^thpostoperative day. As pain reduced, patients were able to tolerate a more solid diet with all but 6 tolerating their usual diet. 4 patients developed fever in the 1^stpostoperative day which did not progress to the next day. One patient had fever on the 4^thand 7^thpostoperative day and was admitted in the paediatrics' ward with a chest infection. All these patients with history of fever were in the group that was on oral postoperative Co-Amoxiclav.</p> <p>Conclusion</p> <p>A single intraoperative dose of Co-Amoxiclav given intravenously at induction was found to be just as effective as a full oral course of the same given postoperatively in the prevention of post adenotonsillectomy morbidity. The prophylactic dose is favoured over the later as it is cheaper, ensures compliance and relieves off the need for refrigeration of the oral suspension as not all have access to refrigeration in low economy countries as ours.</p> <p>Trial registration</p> <p>ClinicalTrials.gov: <a href="http://www.clinicaltrials.gov/ct2/show/NCT01267942">NCT01267942</a></p

Prevalence of abnormal aminoglycoside trough levels in children with clinically suspected gram negative infections at a tertiary level hospital In Kenya-a cross sectional study

Background: Aminoglycosides are used to treat severe gram-negative infections. The associated risk of nephro toxicity necessitates therapeutic drug level monitoring. Objectives: This study attempted to determine prevalence of abnormal aminoglycoside trough levels in children below the age of 12 years and to determine if glomerular filtration rate (GFR) estimation using Schwartz formula correlates with drug trough levels. Materials and Methods: This was a cross sectional study enrolling children aged one day to 12 years on aminoglycosides, at a private tertiary facility in Nairobi. Aminoglycoside drug trough levels and serum creatinine measurements were analyzed for a calculated sample size of 81 patients. GFR was estimated using Schwartz formula. The Pearson correlation coefficient was calculated between the drug trough levels and estimated GFR. Results: Median age of participants was 3 days (IQR 19). The prevalence of abnormal aminoglycoside trough levels was 4.9% (95% CI 1.4% to 12.2%). The Pearson correlation coefficient between aminoglycoside trough levels and GFR was -0.342. The area under the receiver operating characteristic (ROC) curve was 0.6185 Conclusion: The prevalence of abnormal aminoglycoside trough levels was low and therefore the routine screening of patients on aminoglycoside therapy for toxicity using drug trough levels may not be justified

Distribution, charactisation and management of 'Tomato spotted wilt virus' and its vectors in tomato production systems in Kenya

'Tomato spotted wilt virus' (family 'Bunyaviridae', genus 'Tospovirus') is an important virus infecting horticultural crops and is transmitted solely by thrips species. The virus infects a wide range of plant species and presence of 'Frankliniella occidentalis', reported to be the most efficient vector species has complicated its management. TSWV was first reported in Kenya in 1999, causing serious yield losses in tomato production, and has continued to cause sporadic yield losses. This study was undertaken to determine the distribution and genetic diversity of the virus a decade after its incursion into Kenya. The study further evaluated important factors in the epidemiology of the disease and its management

Bacteriology of chronic suppurative otitis media (CSOM) in children in Garissa district, Kenya: A point prevalence study

Objectives To identify by type and sensitivity to drugs the bacteria found in ears of school-going children with chronic otitis media in Garissa district. Methods Study design: This was a descriptive prevalence study of CSOM bacterial flora in eligible ears conducted among a cohort of children attending public and private primary as well as Islamic religious schools, screened for chronic ear discharge in Garissa district, Kenya. Procedure and bacteriological techniques: We used sterile swab-sticks to collect a specimen of the discharge from eligible ears of consenting pupils at the induction stage of the zinc supplementation trial for treatment of chronic suppurative otitis media conducted between January and July 2010. All pupils below 18 years present on day of visit were eligible. Both aerobic and anaerobic bacterial cultures were done to identify clinically and epidemiologically important bacteria. Sensitivity tests were based on disc diffusion methods. Results are presented as frequencies and proportions. Results Of the pupils seen, 61% were still in pre- or lower primary school. Majority were aged 13 and 14 years. Of the 261 ear swab samples processed, 336 isolates – either in mixed or pure flora – were identified, being almost exclusively aerobes. Proteus spp., Enterococcus, Staphylococcus aureus and Pseudomonas spp. were isolated in 32.7%, 28.6%, 12.8% and 11.3% respectively. Proteus was susceptible to majority of the antibiotics tested for, while Enterococcus was poorly susceptible. Conclusions Aerobic bacteria were most prevalent in this study. Several of the bacteria identified are known to require iron for their growth. This may be important for CSOM treatment if biofilm formation is involved in pathogenesis. Majority of the isolates were susceptible to basic antibiotics compared to Enterococcus bacteria. This portends an important consideration for clinical management and therapeutic decision-making. Additionally, given the prevalence of Enterococcus bacteria, which is an indicator of faecal contamination of the environment, there is need to consider relevant public health components in managing childhood CSOM besides the clinical ones alone

Distribution and genetic diversity of 'Tomato spotted wilt virus' following an incursion into Kenya

'Tomato spotted wilt virus' (TSWV) affects the production of many horticultural crops worldwide. It was first reported from Kenya in 1999. The occurrence, distribution and genetic diversity of TSWV were evaluated in four tomato production areas in Kenya a decade after this incursion. The awareness of TSWV and its vectors among farmers was assessed through a questionnaire while plant samples including tomato leaves and fruit were collected from diseased and non-diseased plants. The samples were assayed for TSWV using ELISA and reverse transcriptase-polymerase chain reaction, and the resulting positive samples were sequenced. There was less awareness of the virus, its vectors and alternate hosts among farmers, despite the occurrence of the disease for over a decade. A total of 89 of 408 tomato samples tested positive for TSWV. Most of the positive samples came from Nakuru, where the virus was first detected, with only a single positive sample being obtained from Loitokitok and none from Bungoma or Kirinyaga. A phylogenetic analysis based on partial nucleocapsid (N) protein gene sequences suggested that the Kenyan isolates formed a single subgroup nested within a cluster of isolates that came predominantly from Europe. This indicated a single introduction that had undergone limited diversification. The study revealed that the disease has persisted in the area to which it was first introduced but has had very limited dispersal to other areas

Diversity of Thrips Species and Vectors of Tomato Spotted Wilt Virus in Tomato Production Systems in Kenya

Thrips have been recognized as primary vectors of tomato spotted wilt virus (TSWV) with 'Frankliniella occidentalis' (Pergande) reported as the most important and efficient vector, while other species such as 'Thrips tabaci' Lindeman also include populations that can vector the virus. A study was undertaken to establish the diversity of thrips and presence of vectors for TSWV in four major tomato production areas in Kenya. The cytochrome oxidase 1 (CO1) gene was used to generate sequences from thrips samples collected from tomatoes and weeds, and phylogenetic analysis done to establish the variation within potential vector populations. 'Ceratothripoides brunneus' Bagnall was the predominant species of thrips in all areas. 'F. occidentalis' and 'T. tabaci' were abundant in Nakuru, Kirinyaga, and Loitokitok but not detected at Bungoma. Other vectors of tospoviruses identified in low numbers were 'Frankliniella schultzei' (Trybom) and 'Scirtothrips dorsalis' Hood. Variation was observed in 'T. tabaci', 'F. occidentalis', and 'F. schultzei'. Kenyan specimens of 'T. tabaci' from tomato belonged to the arrhenotokous group, while those of 'F. occidentalis' clustered with the Western flower thrips G group. The detection of RNA of TSWV in both of these species of thrips supported the role they play as vectors. The study has demonstrated the high diversity of thrips species in tomato production and the occurrence of important vectors of TSWVand other tospoviruses