Anticoagulation control among patients on vitamin K antagonists in nine countries in Sub-Saharan Africa.

Vitamin K antagonists (VKA) is the primary anticoagulant in most settings of Sub-Saharan Africa. Understanding the quality of anticoagulation services in the continent is vital in optimising the intended benefits. This study assessed the quality of anticoagulation and associated factors among VKA-treated patients in nine SSA countries. We conducted a retrospective cohort study of randomly selected patients on anticoagulation from 20 clinics in Botswana, the Democratic Republic of Congo, Ethiopia, Gambia, Ghana, Mozambique, Nigeria, Tanzania, and South Africa. Eligible participants were those on VKAs for at least three months and with at least four international normalised ratios (INR) results in 2019-2021. We report the proportion of INR values in the therapeutic range, time-in-therapeutic range (TTR) using the Rosendaal method, and the proportion of patients with TTR ≥ 65% (optimal anticoagulation). The mean age was 51.1(16.1) years, and 64.2% were women. The most common indications for VKA included venous thromboembolism (29.6%), prosthetic valves (26.7%) and atrial fibrillation/flutter (30.1%). We analysed 6743 INR tests from 1011 participants, and of these, 48.5% were sub-therapeutic, 34.1% therapeutic, and 17.4% were supratherapeutic relative to disease-specific reference ranges. TTR was calculated for 660 patients using 4927 INR measurements. The median (interquartile range [IQR]) TTR was 35.8(15.9,57.2) %. Optimal anticoagulation control was evident in 19.2% of participants, varying from 2.7% in Tanzania to 23.1% in Ethiopia. The proportion of patients with TTR ≥ 65% was 15,4% for prosthetic heart valves, 21.1% for venous thromboembolism and 23.7% for atrial fibrillation or flutter. Countries with universal health coverage had higher odds of optimal anticoagulation control (adjusted odds ratio (aOR) 1.79, 95% confidence interval [CI], 1.15- 2.81, p = 0.01). Patients on VKAs for different therapeutic indications in SSA had suboptimal TTR. Universal health coverage increased the odds of achieving TTR by 79%. The evidence calls for more intensive warfarin management strategies in SSA, including providing VKA services without out-of-pocket payments.

Evaluating the sensitivity and specificity of Determine™ HIV-1/2 rapid test using a 0.01M phosphate-buffered saline produced at the Medical Research Council Unit The Gambia for the diagnosis of HIV.

BACKGROUND: Human immunodeficiency virus (HIV) rapid diagnostic tests (RDTs) are widely used. However, buffer stockouts commonly lead to utilising non-approved liquids, resulting in errors. Our aim was to evaluate the diagnostic accuracy of an alternative buffer. METHODS: Paired Determine HIV-1/2 rapid tests with commercial buffer and locally produced 0.01M phosphate-buffered saline (PBS) were performed on consecutive consenting individuals requiring HIV testing. Serum samples were sent for confirmation through the local gold-standard algorithm (Murex HIV Ag/Ab, Hexagon HIV with/without Geenius HIV 1/2). Test accuracy, κ and exact McNemar's test were also carried out. RESULTS: Of 167 participants, 137 had confirmatory testing. The sensitivity of the Determine HIV-1/2 test using PBS compared with the gold standard was 100% (95% confidence interval [CI] 90.5 to 100) with a specificity of 98% (95% CI 92.9 to 99.8). The κ value was 0.94 compared with the gold standard and 0.92 compared with the Determine HIV-1/2 test using the commercial buffer. McNemar's test showed no evidence of differing sensitivities. Due to operational constraints, the study included 37 of the 49 positive cases as determined by the sample size calculation, resulting in an attained power of 80% instead of the intended 90%. CONCLUSIONS: These results suggest that 0.01M PBS is an alternative solution for Determine HIV-1/2 when buffer stockouts occur.

Using an Antibiogram Profile to Improve Infection Control and Rational Antimicrobial Therapy in an Urban Hospital in The Gambia, Strategies and Lessons for Low- and Middle-Income Countries.

Antimicrobial resistance is a global health threat and efforts to mitigate it is warranted, thus the need for local antibiograms to improve stewardship. This study highlights the process that was used to develop an antibiogram to monitor resistance at a secondary-level health facility to aid empirical clinical decision making in a sub-Saharan African county. This retrospective cross-sectional descriptive study used 3 years of cumulative data from January 2016 to December 2018. Phenotypic data was manually imputed into WHONET and the cumulative antibiogram constructed using standardized methodologies according to CLSI M39-A4 guidelines. Pathogens were identified by standard manual microbiological methods and antimicrobial susceptibility testing was performed using Kirby-Bauer disc diffusion method according to CLSI M100 guidelines. A total of 14,776 non-duplicate samples were processed of which 1163 (7.9%) were positive for clinically significant pathogens. Among the 1163 pathogens, E. coli (n = 315) S. aureus (n = 232), and K. pneumoniae (n = 96) were the leading cause of disease. Overall, the susceptibility for E. coli and K. pneumoniae from all samples were: trimethoprim-sulfamethoxazole (17% and 28%), tetracycline (26% and 33%), gentamicin (72% and 46%), chloramphenicol (76 and 60%), and ciprofloxacin (69% and 59%), and amoxicillin/clavulanic (77% and 54%) respectively. Extended spectrum beta-lactamase (ESBL) resistance was present in 23% (71/315) vs. 35% (34/96) respectively. S. aureus susceptibility for methicillin was 99%. This antibiogram has shown that improvement in combination therapy is warranted in The Gambia.

Genomic epidemiology of SARS-CoV-2 infections in The Gambia: an analysis of routinely collected surveillance data between March, 2020, and January, 2022.

BACKGROUND: COVID-19, caused by SARS-CoV-2, is one of the deadliest pandemics of the past 100 years. Genomic sequencing has an important role in monitoring of the evolution of the virus, including the detection of new viral variants. We aimed to describe the genomic epidemiology of SARS-CoV-2 infections in The Gambia. METHODS: Nasopharyngeal or oropharyngeal swabs collected from people with suspected cases of COVID-19 and international travellers were tested for SARS-CoV-2 with standard RT-PCR methods. SARS-CoV-2-positive samples were sequenced according to standard library preparation and sequencing protocols. Bioinformatic analysis was done using ARTIC pipelines and Pangolin was used to assign lineages. To construct phylogenetic trees, sequences were first stratified into different COVID-19 waves (waves 1-4) and aligned. Clustering analysis was done and phylogenetic trees constructed. FINDINGS: Between March, 2020, and January, 2022, 11 911 confirmed cases of COVID-19 were recorded in The Gambia, and 1638 SARS-CoV-2 genomes were sequenced. Cases were broadly distributed into four waves, with more cases during the waves that coincided with the rainy season (July-October). Each wave occurred after the introduction of new viral variants or lineages, or both, generally those already established in Europe or in other African countries. Local transmission was higher during the first and third waves (ie, those that corresponded with the rainy season), in which the B.1.416 lineage and delta (AY.34.1) were dominant, respectively. The second wave was driven by the alpha and eta variants and the B.1.1.420 lineage. The fourth wave was driven by the omicron variant and was predominantly associated with the BA.1.1 lineage. INTERPRETATION: More cases of SARS-CoV-2 infection were recorded in The Gambia during peaks of the pandemic that coincided with the rainy season, in line with transmission patterns for other respiratory viruses. The introduction of new lineages or variants preceded epidemic waves, highlighting the importance of implementing well structured genomic surveillance at a national level to detect and monitor emerging and circulating variants. FUNDING: Medical Research Unit The Gambia at London School of Hygiene & Tropical Medicine, UK Research and Innovation, WHO.

Clinical characteristics of people with diabetic ketoacidosis at a clinic in The Gambia: a retrospective study

Background: Diabetic ketoacidosis (DKA) remains an important cause of hospitalisation and death in people with diabetes mellitus (DM) living in low- and middle-income countries. The clinical profile of patients with DKA varies, and maybe contributory to the outcomes observed globally. The aim of this study was to describe the clinical characteristics of people with diabetic ketoacidosis (DKA) seen at a clinic in The Gambia during a one-and-a-half-year period. Methods: This was a retrospective chart review that included people with DM who were seen from June 2017 to December 2018 at the Medical Research Council the Gambia at London School of Hygiene and Tropical Medicine. Biodata, anthropometric and admissions data were extracted for all patients from the electronic medical records system. Data were analysed for differences in clinical and biochemical characteristics on admission for DKA. Results: In total, 23 out of 103 admissions for people with DM were for a diagnosis of DKA during the study period. Sixteen of those included were females and the mean age of all patients was 35 ± 13 years. Two people had type 1 DM and 15 people were categorised as type 2 DM. DM was diagnosed for the first time during admission for DKA for 12 people and 6 people had confirmed sepsis. There were no significant differences in age at diagnosis of DM or biochemical characteristics. Conclusion: DKA was a common indication for admission for people with DM in the Medical Research Council the Gambia at London School of Hygiene and Tropical Medicine and the majority of patients with DKA had type 2 DM. Further studies are needed to describe DKA in this setting more accurately.

Circulation of respiratory viruses during the COVID-19 pandemic in The Gambia.

Background: In many countries, non-pharmaceutical interventions to limit severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission resulted in significant reductions in other respiratory viruses. However, similar data from Africa are limited. We explored the extent to which viruses such as influenza and rhinovirus co-circulated with SARS-CoV-2 in The Gambia during the COVID-19 pandemic.  Methods: Between April 2020 and March 2022, respiratory viruses were detected using RT-PCR in nasopharyngeal swabs from 1397 participants with influenza-like illness. An assay to detect SARS-CoV-2 and a viral multiplex RT-PCR assay was used as previously described  to detect influenza A and B, respiratory syncytial virus (RSV) A and B, parainfluenza viruses 1-4, human metapneumovirus (HMPV), adenovirus, seasonal coronaviruses (229E, OC43, NL63) and human rhinovirus. Results: Overall virus positivity was 44.2%, with prevalence higher in children <5 years (80%) compared to children aged 5-17 years (53.1%), adults aged 18-50 (39.5%) and >50 years (39.9%), p<0.0001. After SARS-CoV-2 (18.3%), rhinoviruses (10.5%) and influenza viruses (5.5%) were the most prevalent. SARS-CoV-2 positivity was lower in children <5 (4.3%) and 5-17 years (12.7%) than in adults aged 18-50 (19.3%) and >50 years (24.3%), p<0.0001. In contrast, rhinoviruses were most prevalent in children <5 years (28.7%), followed by children aged 5-17 (15.8%), adults aged 18-50 (8.3%) and >50 years (6.3%), p<0.0001. Four SARS-CoV-2 waves occurred, with 36.1%-52.4% SARS-CoV-2 positivity during peak months. Influenza infections were observed in both 2020 and 2021 during the rainy season as expected (peak positivity 16.4%-23.5%). Peaks of rhinovirus were asynchronous to the months when SARS-CoV-2 and influenza peaked. Conclusion: Our data show that many respiratory viruses continued to circulate during the COVID-19 pandemic in The Gambia, including human rhinoviruses, despite the presence of NPIs during the early stages of the pandemic, and influenza peaks during expected months.

Impact of Personal Cooling on Performance, Comfort and Heat Strain of Healthcare Workers in PPE, a Study From West Africa.

Background: Personal protective equipment (PPE) is an essential component of safely treating suspected or confirmed SARS-CoV-2 patients. PPE acts as a barrier to heat loss, therefore increasing the risk of thermal strain which may impact on cognitive function. Healthcare workers (HCWs) need to be able to prioritize and execute complex tasks effectively to ensure patient safety. This study evaluated pre-cooling and per-cooling methods on thermal strain, thermal comfort and cognitive function during simulated emergency management of an acutely unwell patient. Methods: This randomized controlled crossover trial was run at the Clinical Services Department of the Medical Research Unit The Gambia. Each participant attended two sessions (Cool and Control) in standard PPE. Cool involved pre-cooling with an ice slurry ingestion and per-cooling by wearing an ice-vest external to PPE. Results: Twelve participants completed both sessions. There was a significant increase in tympanic temperature in Control sessions at both 1 and 2 h in PPE (p = 0.01). No significant increase was seen during Cool. Effect estimate of Cool was -0.2°C (95% CI -0.43; 0.01, p = 0.06) post 1 h and -0.28°C (95% CI -0.57; 0.02, p = 0.06) post 2 h on tympanic temperature. Cool improved thermal comfort (p < 0.001), thermal sensation (p < 0.001), and thirst (p = 0.04). No difference on cognitive function was demonstrated using multilevel modeling. Discussion: Thermal strain in HCWs wearing PPE can be safely reduced using pre- and per-cooling methods external to PPE.

Origin of imported SARS-CoV-2 strains in The Gambia identified from whole genome sequences.

The SARS-CoV-2 disease, first detected in Wuhan, China, in December 2019 has become a global pandemic and is causing an unprecedented burden on health care systems and the economy globally. While the travel history of index cases may suggest the origin of infection, phylogenetic analysis of isolated strains from these cases and contacts will increase the understanding and link between local transmission and other global populations. The objective of this analysis was to provide genomic data on the first six cases of SARS-CoV-2 in The Gambia and to determine the source of infection. This ultimately provide baseline data for subsequent local transmission and contribute genomic diversity information towards local and global data. Our analysis has shown that the SARS-CoV-2 virus identified in The Gambia are of European and Asian origin and sequenced data matched patients' travel history. In addition, we were able to show that two COVID-19 positive cases travelling in the same flight had different strains of SARS-CoV-2. Although whole genome sequencing (WGS) data is still limited in sub-Saharan Africa, this approach has proven to be a highly sensitive, specific and confirmatory tool for SARS-CoV-2 detection.

Intense and Mild First Epidemic Wave of Coronavirus Disease, The Gambia.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic is evolving differently in Africa than in other regions. Africa has lower SARS-CoV-2 transmission rates and milder clinical manifestations. Detailed SARS-CoV-2 epidemiologic data are needed in Africa. We used publicly available data to calculate SARS-CoV-2 infections per 1,000 persons in The Gambia. We evaluated transmission rates among 1,366 employees of the Medical Research Council Unit The Gambia (MRCG), where systematic surveillance of symptomatic cases and contact tracing were implemented. By September 30, 2020, The Gambia had identified 3,579 SARS-CoV-2 cases, including 115 deaths; 67% of cases were identified in August. Among infections, MRCG staff accounted for 191 cases; all were asymptomatic or mild. The cumulative incidence rate among nonclinical MRCG staff was 124 infections/1,000 persons, which is >80-fold higher than estimates of diagnosed cases among the population. Systematic surveillance and seroepidemiologic surveys are needed to clarify the extent of SARS-CoV-2 transmission in Africa.

Establishing and operating a 'virtual ward' system to provide care for patients with COVID-19 at home: experience from The Gambia.

Health systems in sub-Saharan Africa have remained overstretched from dealing with endemic diseases, which limit their capacity to absorb additional stress from new and emerging infectious diseases. Against this backdrop, the rapidly evolving COVID-19 pandemic presented an additional challenge of insufficient hospital beds and human resource for health needed to deliver hospital-based COVID-19 care. Emerging evidence from high-income countries suggests that a 'virtual ward' (VW) system can provide adequate home-based care for selected patients with COVID-19, thereby reducing the need for admissions and mitigate additional stress on hospital beds. We established a VW at the Medical Research Council Unit, The Gambia at the London School of Hygiene and Tropical Medicine, a biomedical research institution located in The Gambia, a low-income west African country, to care for members of staff and their families infected with COVID-19. In this practice paper, we share our experience focusing on the key components of the system, how it was set up and successfully operated to support patients with COVID-19 in non-hospital settings. We describe the composition of the multidisciplinary team operating the VW, how we developed clinical standard operating procedures, how clinical oversight is provided and the use of teleconsultation and data capture systems to successfully drive the process. We demonstrate that using a VW to provide an additional level of support for patients with COVID-19 at home is feasible in a low-income country in sub-Saharan Africa. We believe that other low-income or resource-constrained settings can adopt and contextualise the processes described in this practice paper to provide additional support for patients with COVID-19 in non-hospital settings.

The effects of intensive speech treatment on intelligibility in Parkinson's disease: A randomised controlled trial.

BACKGROUND: More than 6,000,000 individuals worldwide are diagnosed with Parkinson's disease (PD). Nearly 90% develop speech signs that may substantially impair their speech intelligibility, resulting in losses in their communication and quality of life. Benefits of intensive speech treatment have been documented for a range of speech signs. However, the critical question of whether speech is more intelligible after treatment has not been investigated in a randomised controlled trial (RCT). We hypothesised that intensive speech treatment would improve speech intelligibility in PD. METHOD: Sixty-four patients with hypokinetic dysarthria secondary to PD participated in this single-centre, parallel arm, statistically-powered RCT. Reporting follows CONSORT guidelines for non-pharmacological treatment. Patients were recruited from US clinics and randomised using a statistician-derived minimisation algorithm, to intensive speech treatment (16 1-hour sessions/1 month) targeting voice (voice group) or targeting articulation (articulation group) or to an untreated group (no treatment group). Speech treatments were delivered by speech clinicians who specialised in treating patients with PD. Trial design minimised bias and supported equipoise. For intelligibility assessment, blinded listeners (n = 117) orthographically transcribed 57 patients' recorded, self-generated narrative speech samples, randomly presented in multi-talker babble noise. Listeners were American-English speakers, ages 18-35 years, with normal hearing. The primary outcome was baseline (pre-treatment) to post-treatment change in transcription accuracy (TA), recognised as the most objective measure of intelligibility. TA was defined as the percentage of words transcribed correctly. Listeners, data collectors, and data managers were blinded to treatment conditions and groups. Reliability was evaluated using intraclass correlation coefficients and differences amongst groups were evaluated by mixed-effects models, in accordance with the intention-to-treat approach.This trial was registered with ClinicalTrials.gov Identifier: NCT00123084. FINDINGS: Between June 23, 2016 and August 14, 2017, blinded listeners transcribed baseline and post-treatment speech samples for intelligibility assessment of 57 patients in the voice (n = 19), articulation (n = 19) and no treatment (n = 19) groups. Between-group differences (d) in changes from baseline to post-treatment in TA indicated significantly greater increases following treatment targeting voice than treatment targeting articulation (d = 26·2%, 95% CI 1·5 - 51·0; p = 0·04; ES=1·0). Differences between TA changes in the treatment targeting voice and in the no treatment group were significant (d = 42·8%, 95% CI 22·4 - 63·2; p = 0·0002; ES=1·8). Differences between TA changes in the treatment targeting articulation and in the no treatment group were not significant (d = 16·5%, 95% CI -6·1 - 39·2; p = 0·147; ES=0·9). INTERPRETATION: These findings provide the first RCT evidence that intensive speech treatment targeting voice improves speech intelligibility in PD. Thus, this evidence-based treatment may positively impact health-related quality of life for patients with PD globally when it is included in patient management.

Viral Etiology, Clinical Features and Antibiotic Use in Children <5 Years of Age in the Gambia Presenting With Influenza-like Illness.

BACKGROUND: Knowledge regarding the prevalence, clinical features and etiology of pediatric influenza-like illness (ILI) remains limited in African settings. Furthermore, it is likely that many children presenting with ILI receive antibiotics unnecessarily. More data are required to develop antimicrobial stewardship practice and guide effective vaccine strategies. We undertook a 1-year prospective study of ILI in the Gambia. METHODS: Children <5 years of age presenting with ILI from March 2018 to March 2019 were recruited. Clinical and antibiotic prescribing data were collected. Nasopharyngeal swabs were collected and analyzed for 12 respiratory viruses using a multiplex polymerase chain reaction. RESULTS: From a total of 735 ILI episodes, 530 (72.1%) nasopharyngeal swabs were positive for ≥1 virus. Of these, 36.7% were positive for rhinovirus, 14.7% for respiratory syncytial virus, 8.4% for influenza and 7.2% for human metapneumovirus. Compared with children <6 months of age, influenza was more common in 6- to 23-month-old children [odd ratio (OR): 5.68; 95% confidence interval (CI): 1.72-18.76; P = 0.004]. Respiratory syncytial virus and human metapneumovirus were associated with low peripheral oxygen saturations (OR: 2.13; 95% CI: 1.23-3.69; P = 0.007; and OR: 2.44; 95% CI: 1.13-5.27; P = 0.023, respectively). Antibiotics were prescribed in 78.3% of all ILI cases. CONCLUSIONS: A broad range of viruses are responsible for pediatric ILI in the Gambia. Refined treatment guidelines, improved diagnostic capacity and vaccines to prevent respiratory viruses will all play a role in reducing antimicrobial use for these cases.

Nasalance in adolescents with autism spectrum disorders.

Purpose: Listener judgments indicate atypical nasal resonance in individuals with Autism Spectrum Disorders (ASD); however, listener perceptions are susceptible to bias and may give unreliable information about a speaker's production of nasal resonance. The current study used Nasometry to obtain an objective estimation of nasal resonance among adolescents with ASD and neurotypical controls.Method: The Nasometer II 6450 (PENTAX Medical, Lincoln Park, New Jersey) was used to collect nasalance from adolescents aged 15-17 years with ASD (n = 11) and matched controls (n = 11) across two separate speech tasks: (1) passage reading and (2) spontaneous speech.Result: Adolescents with ASD evidenced significantly higher nasalance scores compared to controls, particularly in the passage loaded with bilabial plosives and some nasals (Bobby) as well as non-nasal words extracted from spontaneous speech. In addition, adolescents with ASD had significantly higher nasalance ratios than controls. Significant group differences were driven by a subset of participants with ASD.Conclusion: Perceptual judgements of nasality noted in previous autism studies are quantified by an increase in nasal energy compared to oral energy. The current data suggest hypernasality is present in a subset of people with ASD rather than being a general feature of speech in autism.

Community-acquired Invasive Bacterial Disease in Urban Gambia, 2005-2015: A Hospital-based Surveillance.

BACKGROUND: Invasive bacterial diseases cause significant disease and death in sub-Saharan Africa. Several are vaccine preventable, although the impact of new vaccines and vaccine policies on disease patterns in these communities is poorly understood owing to limited surveillance data. METHODS: We conducted a hospital-based surveillance of invasive bacterial diseases in The Gambia where blood and cerebrospinal fluid (CSF) samples of hospitalized participants were processed. Three surveillance periods were defined in relation to the introduction of pneumococcal conjugate vaccines (PCVs), before (2005- 2009), during (2010-2011) and after (2012-2015) PCV introduction. We determined the prevalences of commonly isolated bacteria and compared them between the different surveillance periods. RESULTS: A total of 14 715 blood and 1103 CSF samples were collected over 11 years; overall, 1045 clinically significant organisms were isolated from 957 patients (972 organisms [6.6%] from blood and 73 [6.6%] from CSF). The most common blood culture isolates were Streptococcus pneumoniae (24.9%), Staphylococcus aureus (22.0%), Escherichia coli (10.9%), and nontyphoidal Salmonella (10.0%). Between the pre-PCV and post-PCV eras, the prevalence of S. pneumoniae bacteremia dropped across all age groups (from 32.4% to 16.5%; odds ratio, 0.41; 95% confidence interval, .29-.58) while S. aureus increased in prevalence, becoming the most prevalent bacteria (from 16.9% to 27.2%; 1.75; 1.26-2.44). Overall, S. pneumoniae (53.4%), Neisseria meningitidis (13.7%), and Haemophilus influenzae (12.3%) were the predominant isolates from CSF. Antimicrobial resistance to common antibiotics was low. CONCLUSIONS: Our findings demonstrate that surveillance data on the predominant pathogens associated with invasive disease is necessary to inform vaccine priorities and appropriate management of patients.

Recognition and management of congenital ichthyosis in a low-income setting.

We report the case of a 3-week old girl in The Gambia who presented to hospital with an undiagnosed skin disorder evolving since birth. Using telemedicine to seek specialist dermatology advice abroad, she was diagnosed with and managed for suspected congenital lamellar ichthyosis. Poor early recognition and limited resources, for both acute and chronic care, created significant challenges to optimal management; these were overcome, in part, by adopting a common sense, back-to-basics approach to treatment and by empowering the parents to take ownership of their infant's daily skin and eye care. This case highlights key global health issues associated with managing chronic, often debilitating, paediatric dermatological conditions in a low-income setting; namely, poor access to important diagnostic tools and medications, lack of experience and expertise in the management of severe skin disease and its associated complications, absence of long-term community support, alternative health beliefs and risk of sociocultural stigma.

Relationship Between F2 Slope and Intelligibility in Parkinson's Disease: Lexical Effects and Listening Environment.

Purpose There is a complex relationship between speech production and intelligibility of speech. The current study sought to evaluate the interaction of the factors of lexical characteristics, listening environment, and the 2nd formant transition (F2 slope) on intelligibility of speakers with Parkinson's disease (PD). Method Twelve speakers with PD and 12 healthy controls read sentences that included words with the diphthongs /aɪ/, /ɔɪ/, and /aʊ/. The F2 slope of the diphthong transition was measured and averaged across the 3 diphthongs for each speaker. Young adult listeners transcribed the sentences to assess intelligibility of words with high and low word frequency and high and low neighborhood density in quiet and noisy listening conditions. The average F2 slope and intelligibility scores were entered into regression models to examine their relationship. Results F2 slope was positively related to intelligibility in speakers with PD in both listening conditions with a stronger relationship in noise than in quiet. There was no significant relationship between F2 slope and intelligibility of healthy speakers. In the quiet condition, F2 slope was only correlated with intelligibility in less-frequent words produced by the PD group. In the noise condition, F2 slope was related to intelligibility in high- and low-frequency words and high-density words in PD. Conclusions The relationship between F2 slope and intelligibility in PD was affected by lexical factors and listening conditions. F2 slope was more strongly related to intelligibility in noise than in quiet for speakers with PD. This relationship was absent in highly frequent words presented in quiet and those with fewer lexical neighbors.

Prevalence of Panton-Valentine Leukocidin (PVL) and Antimicrobial Resistance in Community-Acquired Clinical Staphylococcus aureus in an Urban Gambian Hospital: A 11-Year Period Retrospective Pilot Study.

Background:Staphylococcus aureus is a major human pathogen. Panton-Valentine leukocidin (PVL) is a virulence factor produced by some strains that causes leukocyte lysis and tissue necrosis. PVL-associated S. aureus (PVL-SA) predominantly causes skin and soft-tissue infections (SSTIs) but can also cause invasive infections such as necrotizing pneumonia. It is carried by both community-associated methicillin susceptible S. aureus (CA-MSSA) and methicillin resistant S. aureus (CA-MRSA). This study aims to determine the prevalence of PVL-SA among patients seen at an urban Gambian hospital and associated antibiotic resistance. Methods: Archived clinical S. aureus (70 invasive bacteraemia and 223 non-invasive SSTIs) from 293 patients were retrieved as well as relevant data from clinical records where available. Antibiotic susceptibility was assessed using disc diffusion according to Clinical Laboratory Standards Institute (CLSI) guidelines. Genomic DNA was extracted and the presence of lukF and lukS PVL genes was detected by conventional gel-based PCR. Result: PVL-SA strains accounted for 61.4% (180/293) of S. aureus isolates. PVL prevalence was high in both Gambian bacteraemia and SSTIs S. aureus strains. Antimicrobial resistance was low and included chloramphenicol (4.8%), cefoxitin (2.4%), ciprofloxacin (3.8%), erythromycin (8.9%), gentamicin (5.5%) penicillin (92.5%), tetracycline (41.0%), and sulfamethoxazole-trimethoprim (24.2%). There was no association of PVL with antimicrobial resistance. Conclusion: PVL expression is high among clinical S. aureus strains among Gambian patients. Reporting of PVL-SA clinical infections is necessary to enable the monitoring of the clinical impact of these strains in the population and guide prevention of the spread of virulent PVL-positive CA-MRSA strains. SUMMARY  Staphylococcus aureus (S. aureus) is a major human pathogen with several virulence factors. We performed a retrospective analysis to investigate the prevalence of one such virulence factor (PVL) amongst clinical S. aureus samples. We found a high prevalence in our setting but antimicrobial resistance including methicillin resistance was low.