Newborn and infant hearing screening for early detection of hearing loss in Nairobi, Kenya.

Background: Early detection of hearing loss and subsequent intervention leads to better speech, language and educational outcomes giving way to improved social economic prospects in adult life. This can be achieved through establishing newborn and infant hearing screening programs. Objective: To determine the prevalence of hearing loss in newborns and infants in Nairobi, Kenya. Methods: A cross-sectional pilot study was conducted at the National hospital and at a sub county hospital immunization clinic. A total of 9,963 babies aged 0-3 years, were enrolled in the hearing screening program through convenient sampling over a period of nine months. A case history was administered followed by Distortion Product Oto-acoustic emissions (DPOAEs) and automated auditory brainstem response (AABR) hearing screening. Results: The screening coverage rate was 98.6% (9963/10,104). The referral rate for the initial screen was 3.6% (356/ 9,963), the return rate for follow-up rescreening was 72% (258 babies out of 356) with a lost to follow-up rate of 28% (98/356). The referral rate of the second screen was 10% (26/258). All the 26 babies referred from the second screen returned for diagnostic hearing evaluation and were confirmed with hearing loss, yielding a prevalence of 3/1000. Conclusions: Establishing universal newborn and infant hearing screening programs is essential for early detection and intervention for hearing loss. Data management and efficient follow-up systems are an integral part of achieving diagnostic confirmation of hearing loss and early intervention.

Real-time reverse transcription recombinase polymerase amplification (RT-RPA) assay for detection of cassava brown streak viruses.

Cassava brown streak disease (CBSD) caused by Cassava brown streak virus (CBSV) and Ugandan cassava brown streak virus (UCBSV) is the most economically important viral disease of cassava. As cassava is a vegetatively propagated crop, the development of rapid and sensitive diagnostics would aid in the identification of virus-free planting material and development of effective management strategies. In this study, a rapid, specific and sensitive real-time reverse transcription recombinase polymerase amplification (RT-RPA) assay was developed for real-time detection of CBSV and UCBSV. The RT-RPA was able to detect as little as 2 pg/µl of purified RNA obtained from infected cassava leaves, a sensitivity equivalent to that obtained by quantitative real-time reverse transcription PCR (qRT-PCR), within 20 min at 37 °C. Further, the RT-RPA detected each target virus directly from crude leaf and stem extracts, avoiding the tedious and costly isolation of high-quality RNA. The developed RT-RPA assay provides a valuable diagnostic tool that can be adopted by cassava seed certification and virus resistance breeding programs to ensure distribution of virus-free cassava planting materials to farmers. This is the first report on the development and validation of crude sap-based RT-RPA assay for the detection of cassava brown streak viruses (UCBSV and CBSV) infection in cassava plants.

Hearing Loss Detection and Early Intervention Strategies in Kenya.

Background: Thirty-four million children globally have disabling hearing loss, with the highest prevalence in low- and middle-income countries (LMICs). Early identification and management is crucial, yet barriers to screening and treatment of hearing loss are extensive in LMICs. Unaddressed hearing loss negatively impacts individuals and communities. The WHO's 2021 World Report on Hearing urges the development of Ear and Hearing Care (EHC) programs to improve access to all aspects of care, including screening, diagnostics, management, and developmental support. A joint Nairobi- and Seattle-based group convened in 2021 to discuss strategies for program development in Kenya, as presented in this paper. Findings: Developing a national EHC program must include the necessary support services for a child with a diagnosed hearing loss, while simultaneously promoting engagement of family, community, and healthcare workers. Existing government and healthcare system policies and priorities can be leveraged for EHC programming. Strategies for success include strengthening connections between policymakers at national, county, and municipal levels and local champions for the EHC agenda, with a concurrent focus on policy, early detection and intervention, habilitation, and family-centered care. Updates to health policy and funding to support the accessibility of services and equipment should focus on leveraging national healthcare coverage for hearing technologies and services, strengthening referral pathways, training to bolster the workforce, and metrics for monitoring and evaluation. Additional strategies to support forward progress include strategic engagement of partners and leveraging local partners for phased scale-up. Conclusions and Recommendations: Recommendations to strengthen EHC within the Kenyan health system include concurrent leverage of existing health policies and priorities, partner engagement, and strengthening referral pathways, monitoring and evaluation, and training. These strategies may be generalized to other countries too.

Distribution and Molecular Diversity of Whitefly Species Colonizing Cassava in Kenya.

The whitefly, Bemisia tabaci (Gennadium, Hemiptera) has been reported to transmit viruses that cause cassava mosaic disease (CMD) and cassava brown streak disease (CBSD) in many parts of sub-Saharan Africa (SSA). Currently, there is limited information on the distribution, species and haplotype composition of the whitefly populations colonizing cassava in Kenya. A study was conducted in the major cassava growing regions of Kenya to address this gap. Analyses of mitochondrial DNA cytochrome oxidase 1 (mtCO1) sequences revealed the presence of four distinct whitefly species: Bemisia tabaci, Bemisia afer, Aleurodicus dispersus and Paraleyrodes bondari in Kenya. The B. tabaci haplotypes were further resolved into SSA1, SSA2 and Indian Ocean (IO) putative species. The SSA1 population had three haplogroups of SSA1-SG1, SSA-SG2 and SSA1-SG3. Application of KASP genotyping grouped the Bemisia tabaci into two haplogroups namely sub-Saharan Africa East and Southern Africa (SSA-ESA) and sub-Saharan Africa East and Central Africa (SSA-ECA). The study presents the first report of P. bondari (Bondar's nesting whitefly) on cassava in Kenya. Bemisia tabaci was widely distributed in all the major cassava growing regions in Kenya. The increased detection of different whitefly species on cassava and genetically diverse B. tabaci mitotypes indicates a significant influence on the dynamics of cassava virus epidemics in the field. The study highlights the need for continuous monitoring of invasive whitefly species population on cassava for timely application of management practices to reduce the impact of cassava viral diseases and prevent potential yield losses.

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

BACKGROUND: 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.

Otitis Media and Its Sequelae in Kenyan Schoolchildren.

BACKGROUND: The goal of this study was to obtain representative Kenyan data on the point prevalence of acute otitis media (AOM) and its sequelae (otitis media with effusion [OME] and chronic suppurative otitis media [CSOM]), a major cause of preventable hearing loss in children in developing countries. In Africa, there are limited studies on the prevalence of AOM and its sequelae in children. METHODS: Study subjects were children aged 2 to 15 years and were enrolled from randomly selected preprimary and primary schools. After parental or guardian consent, subjects had a questionnaire administered, otoscopy and tympanometry were done, and audiometry was performed on those with ear problems detected on these examinations. RESULTS: A total of 9825 (75%) children was from rural schools. The prevalence of CSOM was 15 of 1000, OME was 15 of 1000, and AOM was 7 of 1000 children. Rural Rift Valley schoolchildren had the highest prevalence of CSOM (24 of 1000) compared with other regions (12 of 1000; P < .0001). Ear discharge occurred before 3.5 years in 50% of 901 children with ear discharge. A history of ear discharge was associated with abnormal tympanograms (odds ratio [OR], 11.9-19.2) and mild-to-severe hearing loss (OR, 21.6-38.6), even in children without ear disease (OR, 10.7-24.4). CONCLUSIONS: The burden of AOM sequelae in Kenyan preschool and schoolchildren is significant, and it occurs mostly in the first 4 years of life. By preventing early recurrent AOM, pneumococcal vaccination might partly avert nonreversible sequelae.

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 TSWV and other tospoviruses.

GDP Matters: Cost Effectiveness of Cochlear Implantation and Deaf Education in Sub-Saharan Africa.

HYPOTHESIS: Cochlear implantation and deaf education are cost effective in Sub-Saharan Africa. BACKGROUND: Cost effectiveness of pediatric cochlear implantation has been well established in developed countries but is unknown in low resource settings, where access to the technology has traditionally been limited. With incidence of severe-to-profound congenital sensorineural hearing loss 5 to 6 times higher in low/middle-income countries than the United States and Europe, developing cost-effective management strategies in these settings is critical. METHODS: Costs were obtained from experts in Nigeria, South Africa, Kenya, Rwanda, Uganda, and Malawi using known costs and published data, with estimation when necessary. A disability adjusted life years (DALY) model was applied using 3% discounting and 10-year length of analysis. Sensitivity analysis was performed to evaluate the effect of device cost, professional salaries, annual number of implants, and probability of device failure. Cost effectiveness was determined using the WHO standard of cost-effectiveness ratio/gross domestic product per capita (CER/GDP) less than 3. RESULTS: Cochlear implantation was cost effective in South Africa and Nigeria, with CER/GDP of 1.03 and 2.05, respectively. Deaf education was cost effective in all countries investigated, with CER/GDP ranging from 0.55 to 1.56. The most influential factor in the sensitivity analysis was device cost, with the cost-effective threshold reached in all countries using discounted device costs that varied directly with GDP. CONCLUSION: Cochlear implantation and deaf education are equally cost effective in lower-middle and upper-middle income economies of Nigeria and South Africa. Device cost may have greater impact in the emerging economies of Kenya, Uganda, Rwanda, and Malawi.

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. 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.

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

BACKGROUND: 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. METHODS: 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. RESULTS: 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 7th postoperative 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 1st postoperative day which did not progress to the next day. One patient had fever on the 4th and 7th postoperative 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. CONCLUSION: 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. TRIAL REGISTRATION: ClinicalTrials.gov: NCT01267942.

Pattern of congenital neck masses in a Kenyan paediatric population.

BACKGROUND: The distribution of congenital neck masses varies between countries and is important in diagnosis and treatment modalities. Data from Africa is scarce, and altogether absent from Kenya. OBJECTIVE: To describe the pattern of congenital masses in a Kenyan paediatric population. SET UP: Kenyatta National Hospital, Nairobi Kenya. STUDY DESIGN: Prospective descriptive cross-sectional. METHODOLOGY: Children aged 15 years and below with neck masses who presented to various surgical clinics and wards at the Kenyatta National Hospital between December 2006 and April 2007 were included in the study. They were examined for age, gender, type and location of the neck mass. Mode of investigation and final diagnosis were recorded. Data was analyzed by using statistical package for social sciences. Descriptive statistics were applied to determine means, frequencies and modes. Ninety-five percent confidence interval was used and p value of 0.05 taken as significant. Data are presented in form of tables. RESULTS: Two hundred and thirty-five children (129 male) with neck masses were examined. Fifty-one (22%) of these masses were congenital. Thyroglossal duct cysts were the most common (29%) followed by cystic hygromas (21%) and branchial cleft cysts (20%). Fifty-one percent of the masses were present at birth. The midline was the most common location (31.4%) followed by anterior border of sternocleidomastoid (27.5%) and submandibular region (19.6%). Ultrasound was the commonest diagnostic investigation. CONCLUSION: Congenital defects constitute an important differential diagnosis for paediatric neck masses in Kenya. Thyroglossal duct cysts, cystic hygromas and branchial cleft cysts are the most prevalent occurring most commonly in the midline and anterior border of sternocleidomastoid muscle. An understanding of the distribution of these masses improves diagnosis, preoperative decision making and their overall management.

Parental awareness of hearing impairment in their school-going children and healthcare seeking behaviour in Kisumu district, Kenya.

BACKGROUND: Hearing-impaired children who are identified early and appropriately managed have improved outcomes in speech, language, cognitive and social development. Enhanced parental awareness of their child's hearing disability, behavioral, developmental and psychosocial limitations is essential to sustaining timely detection and appropriate intervention. Additionally, availability of services for diagnosis, treatment and habilitation would improve the demand for pedaudiological care in this community. OBJECTIVE: To describe level of parental awareness of childhood HI and the pattern of access to and utilization of ambulatory care services. SUBJECTS: Thirty-three parents of lower primary school-going children who failed audiometric screening from sampled schools in Kisumu district, western Kenya. MAIN OUTCOME MEASURES: First person to detect HI, age of child at first suspicion of HI, source of ambulatory health care and use of the health care facilities. RESULTS: The prevalence of HI was 2.48%. Most parents/guardians (69.7%) were aware of their child's hearing impairment. Of these, 63.6% were first to detect HI in the pupils, while 30.3% were detected by screen. Most children (57.2%) were first recognized with (HI) after age 2 years. The mean age at identification was 5.5 years. The median travel distance to the preferred health care facility was 2 km (IQR 1-2.5). Parents seldom sought or lacked help for their hearing-impaired children. Of 27.3% who asked for hearing assessment, 9.1% received some counsel on HI and 12.1% received medication, one (3%) was referred for audiological assessment and none used a hearing aid. Use of health facilities for maternal care was (65.7%) and immunization (62.9%). CONCLUSIONS: Despite adequate parental awareness of chronic childhood disability, health facilities were underutilized. This indicates the need to further stimulate and maintain a desirable level of uptake of services for diagnosis, treatment and habilitation of childhood HI, while sustaining delivery of effective and acceptable high quality paediatric care.

Topical quinolone vs. antiseptic for treating chronic suppurative otitis media: a randomized controlled trial.

OBJECTIVE: To compare a topical quinolone antibiotic (ciprofloxacin) with a cheaper topical antiseptic (boric acid) for treating chronic suppurative otitis media in children. DESIGN: Randomized controlled trial. SETTING AND PARTICIPANTS: A total of 427 children with chronic suppurative otitis media enrolled from 141 schools following screening of 39 841 schoolchildren in Kenya. Intervention Topical ciprofloxacin (n = 216) or boric acid in alcohol (n = 211); child-to-child treatment twice daily for 2 weeks. MAIN OUTCOME MEASURES: Resolution of discharge (at 2 weeks for primary outcome), healing of the tympanic membrane, and change in hearing threshold from baseline, all at 2 and 4 weeks. RESULTS: At 2 weeks, discharge was resolved in 123 of 207 (59%) children given ciprofloxacin, and in 65 of 204 (32%) given boric acid (relative risk 1.86; 95% CI 1.48-2.35; P < 0.0001). This effect was also significant at 4 weeks, and ciprofloxacin was associated with better hearing at both visits. No difference with respect to tympanic membrane healing was detected. There were significantly fewer adverse events of ear pain, irritation, and bleeding on mopping with ciprofloxacin than boric acid. CONCLUSIONS: Ciprofloxacin performed better than boric acid and alcohol for treating chronic suppurative otitis media in children in Kenya.