Seroprevalence of Anti-Dengue Virus 2 Serocomplex antibodies in out-patients with fever visiting selected hospitals in rural parts of western Kenya in 2010-2011: A cross sectional study

Introduction: There has been a recent increase in the spread of dengue to rural areas. Rural parts of western kenya are naturally prone to mosquito-borne diseases, however, limited research has been documented on infections with dengue. This study therefore investigated the presence of antibodies against dengue virus 2 (denv-2) in a cross-section of febrile out-patients visiting three selected hospitals to assess the level of exposure and to possibly identify the epidemiologic and clinical factors of seropositive participants. Methods: In a cross-sectional study, we administered a questionnaire and used indirect elisa to test for the presence of denv-2 antibodies in febrile outpatients (n=422) visiting three selected hospitals in rural western  kenya. All positive and borderline samples were re-evaluated by plaque reduction neutralization tests (prnt).Results: The prevalence of denv-2 serocomplex antibodies was 8.5% by indirect elisa and 1.2% by prnt. Using bivariable analysis, age (p<0.0001), headache (or, 3.4 (1.6-7.4); p=0.002), retro-orbital pain (or, 3.1  (1.2-7.7); p=0.015), muscle ache (or, 2.6 (1.3-5.2); p= 0.007), jointpain (or, 3.5 (1.7-7.3); p=0.001) and abdominal pain (or, 9.5  (2.44-37.24); p=0.001) were significantly associated with denv-2 seropositivity.Conclusion: This study confirms that there is an existence of dengue virus 2 circulating in regions of western kenya. Age, headache, retro-orbitalpain, muscle ache, joint pain and abdominal pain were associated with increased denv-2 seropositivity

Seroprevalence of Dengue virus among febrile patients visiting selected Hospitals in the Western Region of Kenya, 2010/2011

Background: Dengue fever (DF) and Dengue Hemorrhagic fever’s (DHF) lack of an effective vaccine and specific treatment promotes the diseases’ significance as a public health problem leading to increased morbidity and mortality. The disease is caused by any four closely-related, but antigenically distinct, Dengue virus (DENV) serotypes; DENV-1, DENV-2, DENV-3, and DENV-4 transmitted through mosquito vectors, Aedes mosquitoes. Currently, there is scanty information on its incidence and prevalence in populations naturally-exposed to mosquito-borne diseases in western Kenya.Methods: This study was therefore designed to determine the sero-prevalence of DF in patients (n=422, aged>5 years) presenting with fever at three selected health facilities in Kenya; Anderson Medical Centre (in Trans-Nzoia District in Rift Valley Province), and KEMRI/CIPDCR Alupe Clinic and Alupe Sub-district Hospital (in Teso-south District of Western Province). Furthermore, the socio-demographic characteristics associated with potential risk on sero-prevalence of dengue virus were evaluated. Using serum, indirect ELISA was performed as the screening test with Plaque Reduction Neutralization Test (PRNT) as the confirmatory test, while sociodemographic characteristics were evaluated using structured questionnaires. Chi-square tests were used to test for proportionality.Results: Overall, a low sero-prevalence of 1.2% (5/422) was recorded in the two regions. Among the main significant symptoms of classical DF were retro-orbital pain (OR; 7.75, 95% CI; 1.25-48.07, P=0.013), muscle ache (OR; 10.89, 95% CI; 1.20-78.50, P=0.016) and joint pain (OR; 53.47, 95% CI; 1.22-45.32, P=0.009). In addition, walls with cracks (OR; 8.75, 95% CI; 1.43-2.389, P<0.001), place of storage of water vessel (OR; 3.20, 95% CI; 2.78-68.10, P=0.014), burning of charcoal (OR; 0.06, 95% CI; 0.01-0.38, P<0.001) and farming (OR; 8.83, 95% CI; 1.97-79.78, P<0.001) were significantly associated with DENV-2 sero-positivity. The current study identifies additional factors that may predispose to DF in populations naturally-exposed to mosquito-borne diseases.Conclusion: The overall seroprevalence was low but non-zero implying that dengue is not a main cause of febrile illness in these study regions, but it may be a potential hazard to public health.Keywords: sero-prevalence, dengue virus, health facilities, KenyaAfr J Health Sci. 2013; 26:248-27

Factors associated with superficial mycoses in patients visiting Alupe Clinic and its environs in Busia western Kenya

Background: Globally, Superficial fungal infections are common problems in patients infected human immunodeficiency virus (HIV).The most common, predisposition being unknown HIV status and low socio-economic factors.Objective: The aim of this study was to identify factors associated with Superficial mycoses in patients attending Alupe Outpatient Clinic and its environs. After ethical approval, was obtained from ethical review committee, KEMRI.Methods: A cross-sectional study was conducted in 371 patients from two health facilities in Busia County Kenya. Data was collected using semi structured questionnaire after patients had consented. Quantitative data was analyzed using Statistical Package for Social Sciences (SPSS) version 20.Results: Of 371 respondents; 42.86% (159) were males and 57.14% (212) were females. The mean age for both sexes was 30.8 years with std. dev of 20.0046 and a range of [1,89].The HIV status for respondents were; negative 49.33%, positive 6.20%, unknown status 44.47% respectively.Conclusion: The factors associated with superficial mycoses in patients visiting Alupe Outpatient Clinic and its environs were statistically significant and were majorly associated with; age, gender, HIV status, occupation, site of infection and County. Further research is needed to establish why there is high prevalence of superficial mycoses among; Farmers, business, pupils, students, teachers and those who are unemployed. HIV/AIDS testing and awareness as a predisposition should be prioritized in future studies.Keywords: Superficial mycosis, Human Immunodeficiency Virus, Busi

EuCARE-hospitalised study protocol: a cohort study of patients hospitalised with COVID-19 in the EuCARE project

Background: Severe acute respiratory syndrome coronavirus 2 (SARS CoV-2), the virus responsible for coronavirus disease 2019 (COVID-19), can lead to hospitalisation, particularly in elderly, immunocompromised, and non-vaccinated or partially vaccinated individuals. Although vaccination provides protection, the duration of this protection wanes over time. Additional doses can restore immunity, but the influence of viral variants, specific sequences, and vaccine-induced immune responses on disease severity remains unclear. Moreover, the efficacy of therapeutic interventions during hospitalisation requires further investigation. The study aims to analyse the clinical course of COVID-19 in hospitalised patients, taking into account SARS-CoV-2 variants, viral sequences, and the impact of different vaccines. The primary outcome is all-cause in-hospital mortality, while secondary outcomes include admission to intensive care unit and length of stay, duration of hospitalisation, and the level of respiratory support required. Methods: This ongoing multicentre study observes hospitalised adult patients with confirmed SARS-CoV-2 infection, utilising a combination of retrospective and prospective data collection. It aims to gather clinical and laboratory variables from around 35,000 patients, with potential for a larger sample size. Data analysis will involve biostatistical and machine-learning techniques. Selected patients will provide biological material. The study started on October 14, 2021 and is scheduled to end on October 13, 2026. Discussion: The analysis of a large sample of retrospective and prospective data about the acute phase of SARS CoV-2 infection in hospitalised patients, viral variants and vaccination in several European and non-European countries will help us to better understand risk factors for disease severity and the interplay between SARS CoV-2 variants, immune responses and vaccine efficacy. The main strengths of this study are the large sample size, the long study duration covering different waves of COVID-19 and the collection of biological samples that allows future research. Trial registration: The trial has been registered on ClinicalTrials.gov. The unique identifier assigned to this trial is NCT05463380

The potential for quality assurance systems to save costs and lives:the case of early infant diagnosis of HIV

OBJECTIVES: Scaling up of point-of-care testing (POCT) for early infant diagnosis of HIV (EID) could reduce the large gap in infant testing. However, suboptimal POCT EID could have limited impact and potentially high avoidable costs. This study models the cost-effectiveness of a quality assurance system to address testing performance and screening interruptions, due to, for example, supply stockouts, in Kenya, Senegal, South Africa, Uganda and Zimbabwe, with varying HIV epidemics and different health systems. METHODS: We modelled a quality assurance system-raised EID quality from suboptimal levels: that is, from misdiagnosis rates of 5%, 10% and 20% and EID testing interruptions in months, to uninterrupted optimal performance (98.5% sensitivity, 99.9% specificity). For each country, we estimated the 1-year impact and cost-effectiveness (US$/DALY averted) of improved scenarios in averting missed HIV infections and unneeded HIV treatment costs for false-positive diagnoses. RESULTS: The modelled 1-year costs of a national POCT quality assurance system range from US$ 69 359 in South Africa to US$334 341 in Zimbabwe. At the country level, quality assurance systems could potentially avert between 36 and 711 missed infections (i.e. false negatives) per year and unneeded treatment costs between US$ 5808 and US$ 739 030. CONCLUSIONS: The model estimates adding effective quality assurance systems are cost-saving in four of the five countries within the first year. Starting EQA requires an initial investment but will provide a positive return on investment within five years by averting the costs of misdiagnoses and would be even more efficient if implemented across multiple applications of POCT

Species-Specific Serological Detection for Schistosomiasis by Serine Protease Inhibitor (SERPIN) in Multiplex Assay

Background: Both Schistosoma mansoni and Schistosoma haematobium cause schistosomiasis in sub-Saharan Africa. We assessed the diagnostic value of selected Schistosoma antigens for the development of a multiplex serological immunoassay for sero-epidemiological surveillance. Methodology/Principal Findings: Diagnostic ability of recombinant antigens from S. mansoni and S. haematobium was assessed by Luminex multiplex immunoassay using plasma from school children in two areas of Kenya, endemic for different species of schistosomiasis. S. mansoni serine protease inhibitor (SERPIN) and Sm-RP26 showed significantly higher reactivity to patient plasma as compared to the control group. Sm-Filamin, Sm-GAPDH, Sm-GST, Sm-LAP1, Sm-LAP2, Sm-Sm31, Sm-Sm32 and Sm-Tropomyosin did not show difference in reactivity between S. mansoni infected and uninfected pupils. Sm-RP26 was cross-reactive to plasma from S. haematobium patients, whereas Sm-SERPIN was species-specific. Sh-SEPRIN was partially cross-reactive to S. mansoni infected patients. ROC analysis for Sm-RP26, Sm-SERPIN and Sh-SERPIN showed AUC values of 0.833, 0.888 and 0.947, respectively. Using Spearman’s rank correlation coefficient analysis, we also found significant positive correlation between the number of excreted eggs and median fluorescence intensity (MFI) from the multiplex immunoassays for Sm-SERPIN (ρ = 0.430, p-value = 0.003) and Sh-SERPIN (ρ = 0.433, p-value = 0.006). Conclusions/Significance: Sm-SERPIN is a promising species-specific diagnostic antigen. Sh-SEPRIN was partially cross-reactive to S. mansoni infected patients. SERPINs showed correlation with the number of excreted eggs. These indicate prospects for inclusion of SERPINs in the multiplex serological immunoassay system

Results and harmonization guidelines from two large-scale international Elispot proficiency panels conducted by the Cancer Vaccine Consortium (CVC/SVI)

The Cancer Vaccine Consortium of the Sabin Vaccine Institute (CVC/SVI) is conducting an ongoing large-scale immune monitoring harmonization program through its members and affiliated associations. This effort was brought to life as an external validation program by conducting an international Elispot proficiency panel with 36 laboratories in 2005, and was followed by a second panel with 29 participating laboratories in 2006 allowing for application of learnings from the first panel. Critical protocol choices, as well as standardization and validation practices among laboratories were assessed through detailed surveys. Although panel participants had to follow general guidelines in order to allow comparison of results, each laboratory was able to use its own protocols, materials and reagents. The second panel recorded an overall significantly improved performance, as measured by the ability to detect all predefined responses correctly. Protocol choices and laboratory practices, which can have a dramatic effect on the overall assay outcome, were identified and lead to the following recommendations: (A) Establish a laboratory SOP for Elispot testing procedures including (A1) a counting method for apoptotic cells for determining adequate cell dilution for plating, and (A2) overnight rest of cells prior to plating and incubation, (B) Use only pre-tested serum optimized for low background: high signal ratio, (C) Establish a laboratory SOP for plate reading including (C1) human auditing during the reading process and (C2) adequate adjustments for technical artifacts, and (D) Only allow trained personnel, which is certified per laboratory SOPs to conduct assays. Recommendations described under (A) were found to make a statistically significant difference in assay performance, while the remaining recommendations are based on practical experiences confirmed by the panel results, which could not be statistically tested. These results provide initial harmonization guidelines to optimize Elispot assay performance to the immunotherapy community. Further optimization is in process with ongoing panels

Genetic Analysis of HIV-1 Subtypes in Nairobi, Kenya

Background: Genetic analysis of a viral infection helps in following its spread in a given population, in tracking the routes of infection and, where applicable, in vaccine design. Additionally, sequence analysis of the viral genome provides information about patterns of genetic divergence that may have occurred during viral evolution. Objective: In this study we have analyzed the subtypes of Human Immunodeficiency Virus -1 (HIV-1) circulating in a diverse sample population of Nairobi, Kenya. Methodology: 69 blood samples were collected from a diverse subject population attending the Aga Khan University Hospital in Nairobi, Kenya. Total DNA was extracted from peripheral blood mononuclear cells (PBMCs), and used in a Polymerase Chain Reaction (PCR) to amplify the HIV gag gene. The PCR amplimers were partially sequenced, and alignment and phylogenetic analysis of these sequences was performed using the Los Alamos HIV Database. Results: Blood samples from 69 HIV-1 infected subjects from varying ethnic backgrounds were analyzed. Sequence alignment and phylogenetic analysis showed 39 isolates to be subtype A, 13 subtype D, 7 subtype C, 3 subtype AD and CRF01_AE, 2 subtype G and 1 subtype AC and 1 AG. Deeper phylogenetic analysis revealed HIV subtype A sequences to be highly divergent as compared to subtypes D and C. Conclusion: Our analysis indicates that HIV-1 subtypes in the Nairobi province of Kenya are dominated by a genetically diverse clade A. Additionally, the prevalence of highly divergent, complex subtypes, intersubtypes, and the recombinant forms indicates viral mixing in Kenyan population, possibly as a result of dual infections

Are slum dwellers at heightened risk of HIV infection than other urban residents? Evidence from population-based HIV prevalence surveys in Kenya

In 2008, the global urban population surpassed the rural population and by 2050 more than 6 billion will be living in urban centres. A growing body of research has reported on poor health outcomes among the urban poor but not much is known about HIV prevalence among this group. A survey of nearly 3000 men and women was conducted in two Nairobi slums in Kenya between 2006 and 2007, where respondents were tested for HIV status. In addition, data from the 2008/2009 Kenya Demographic and Health Survey were used to compare HIV prevalence between slum residents and those living in other urban and rural areas. The results showed strong intra-urban differences. HIV was 12% among slum residents compared with 5% and 6% among non-slum urban and rural residents, respectively. Generally, men had lower HIV prevalence than women although in the slums the gap was narrower. Among women, sexual experience before the age of 15 compared with after 19 years was associated with 62% higher odds of being HIV positive. There was ethnic variation in patterns of HIV infection although the effect depended on the current place of residence

Safety and immunogenicity of the candidate tuberculosis vaccine MVA85A in West Africa.

BACKGROUND: Vaccination with a recombinant modified vaccinia Ankara expressing antigen 85A from Mycobacterium tuberculosis, MVA85A, induces high levels of cellular immune responses in UK volunteers. We assessed the safety and immunogenicity of this new vaccine in West African volunteers. METHODS AND FINDINGS: We vaccinated 21 healthy adult male subjects (11 BCG scar negative and 10 BCG scar positive) with MVA85A after screening for evidence of prior exposure to mycobacteria. We monitored them over six months, observing for clinical, haematological and biochemical adverse events, together with assessment of the vaccine induced cellular immune response using ELISPOT and flow cytometry. MVA85A was well tolerated with no significant adverse events. Mild local and systemic adverse events were consistent with previous UK trials. Marked immunogenicity was found whether individuals had a previous BCG scar or not. There was not enhanced immunogenicity in those with a BCG scar, and induced T cell responses were better maintained in apparently BCG-naïve Gambians than previously studied BCG-naïve UK vaccinees. Although responses were predominantly attributable to CD4+ T cells, we also identified antigen specific CD8+ T cell responses, in subjects who were HLA B-35 and in whom enough blood was available for more detailed immunological analysis. CONCLUSIONS: These data on the safety and immunogenicity of MVA85A in West Africa support its accelerated development as a promising booster vaccine for tuberculosis. TRIAL REGISTRATION: ClinicalTrials.gov NCT00423839