Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 38
Filtrar
1.
Microbiol Spectr ; 11(4): e0362322, 2023 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-37338400

RESUMEN

Most investigations into the distribution of methicillin resistant Staphylococcus aureus (MRSA) have focused exclusively on bloodborne infections within individual health care institutions for shorter time periods. This has limited the analysis of a community-spread pathogen to snapshots within the hospital domain. Therefore, in this study we determined the demographic and geographical patterns of MRSA infections and their fluctuation in 10 years within all public hospitals in Gauteng, South Africa. A retrospective analysis of S. aureus samples was done by deduplicating samples in two groups. The sample groups were placed into subsets with respect to demographic and geographical fields and compared across the studied period. Logistic regression was utilized to determine odds ratios for resistant infections in univariate and multivariable configurations. A total of 66,071 unique infectious events were identified from the 148,065 samples received over a 10-year period, out of which 14,356 were identified as bacteremia. MRSA bacteremia rates in Gauteng peaked in 2015 and have since decreased. Within Gauteng, metropolitan areas have the greatest burden of MRSA with children under 5 years of age and males being most affected. Medical wards have the highest S. aureus bacteremia rates, while intensive care units have the highest MRSA bacteremia rates. Patient age, admitting ward, and geographical district are the most important associated factors of resistance. MRSA acquisition rates have shown tremendous growth since 2009 but have since spiked and subsequently decreased. This may be due to the initiation of the National Guidelines on Antimicrobial Stewardship and Infectious Disease Surveillance. Further studies to determine the trajectory of infections are required to support these claims. IMPORTANCE S. aureus is the leading cause of a variety of devastating clinical conditions, including infective endocarditis, bacteremia, and pleuropulmonary infections. It is an important pathogen responsible for substantial morbidity and mortality. MRSA is a variant of interest originally responsible for difficult to treat hospital-acquired infections that has since achieved community spread throughout the world. Most investigations into the distribution of MRSA have focused exclusively on bloodborne infections within individual health care institutions for shorter periods. This has limited the analysis of a community-spread pathogen to snapshots within the hospital domain. This study sought to determine the demographic and geographical patterns of MRSA infections as well as how these have fluctuated over time within all public hospitals. This will also help in understanding the epidemiology and resistance trends of S. aureus, which will help clinicians to understand the clinical prospective and policy makers to design guidelines and strategies for treating such infections.


Asunto(s)
Bacteriemia , Infecciones Comunitarias Adquiridas , Infección Hospitalaria , Staphylococcus aureus Resistente a Meticilina , Infecciones Estafilocócicas , Masculino , Niño , Humanos , Preescolar , Staphylococcus aureus , Estudios Retrospectivos , Estudios Prospectivos , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/epidemiología , Infecciones Comunitarias Adquiridas/epidemiología , Sudáfrica/epidemiología , Infección Hospitalaria/epidemiología , Hospitales Públicos , Bacteriemia/tratamiento farmacológico , Bacteriemia/epidemiología , Antibacterianos/farmacología , Antibacterianos/uso terapéutico
2.
Afr J Lab Med ; 12(1): 1898, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36756217

RESUMEN

This study evaluated the performance of the Xpert Carba-R assay for detecting the five common carbapenemases in carbapenemase-producing organisms in Johannesburg, South Africa between April 2021 and September 2021. The assay demonstrated 98% sensitivity and 97% specificity. It was also able to detect all the carbapenemases in double carbapenemase producers, as well as carbapenemases in non-fermenter organisms. The Xpert Carba-R assay, therefore, allows the rapid (< 1 h) and accurate identification of the common carbapenemases in pure bacterial cultures and rectal swabs. This assay can aid in the timeous institution of appropriate treatment and infection prevention and control measures.

3.
J Infect Public Health ; 16(2): 233-249, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36603376

RESUMEN

Over the last few years, the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) unleashed a global public health catastrophe that had a substantial influence on human physical and mental health, the global economy, and socio-political dynamics. SARS-CoV-2 is a respiratory pathogen and the cause of ongoing COVID-19 pandemic, which testified how unprepared humans are for pandemics. Scientists and policymakers continue to face challenges in developing ideal therapeutic agents and vaccines, while at the same time deciphering the pathology and immunology of SARS-CoV-2. Challenges in the early part of the pandemic included the rapid development of diagnostic assays, vaccines, and therapeutic agents. The ongoing transmission of COVID-19 is coupled with the emergence of viral variants that differ in their transmission efficiency, virulence, and vaccine susceptibility, thus complicating the spread of the pandemic. Our understanding of how the human immune system responds to these viruses as well as the patient groups (such as the elderly and immunocompromised individuals) who are often more susceptible to serious illness have both been aided by this epidemic. COVID-19 causes different symptoms to occur at different stages of infection, making it difficult to determine distinct treatment regimens employed for the various clinical phases of the disease. Unsurprisingly, determining the efficacy of currently available medications and developing novel therapeutic strategies have been a process of trial and error. The global scientific community collaborated to research and develop vaccines at a neck-breaking speed. This review summarises the overall picture of the COVID-19 pandemic, different mutations in SARS-CoV-2, immune response, and the treatment modalities against SARS-CoV-2.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/epidemiología , COVID-19/inmunología , COVID-19/terapia , Mutación , Pandemias/prevención & control , SARS-CoV-2/genética
4.
PLoS One ; 17(11): e0277459, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36367892

RESUMEN

BACKGROUND: Correctional centres provide ideal conditions for tuberculosis (TB) transmission and disease progression. Despite the high TB incidence and incarceration rate in South Africa, data from South African correctional centres are scarce. Thus, the study evaluated TB diagnosis, treatment initiation and completion, and identified prevalent Mycobacterium tuberculosis strains among detainees entering a South African correctional centre. METHODS: This study was a prospective observational study that enrolled participants between February and September 2017 from a correctional centre located in the Western Cape, South Africa. All adult male detainees who tested positive for TB during admission screening were eligible to participate in the study. Sputum samples from enrolled participants underwent smear microscopy and culture. Strain typing was performed on culture-positive samples. The time between specimen collection and diagnosis, the time between diagnosis and treatment initiation, and the proportion of detainees completing TB treatment at the correctional centre were calculated. RESULTS: During the study period, 130 TB cases were detected through routine admission screening (126 male, 2 female, 2 juvenile). Out of the 126 eligible male detainees, 102 were enrolled in the study (81%, 102/126). All TB cases were detected within 30 hrs of admission screening. The majority (78%, 80/102) of participants started treatment within 48 hrs of TB diagnosis. However, only 8% (9/102) of participants completed treatment at the correction centre. Sputa from 90 of the 102 participants were available for smear and culture. There was a high smear positivity, with 49% (44/90) of isolates being smear positive. The Beijing family was the most frequent lineage (55.2%) in the study. CONCLUSION: The strengths of the current TB control efforts at the correctional centre include rapid detection of cases through admission screening and prompt treatment initiation. However, a high number of detainees exiting before treatment completion highlights the need to strengthen links between correctional TB services and community TB services to ensure detainees complete TB treatment after release and prevent TB transmission.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis Pulmonar , Tuberculosis , Adulto , Masculino , Femenino , Humanos , Tuberculosis Pulmonar/epidemiología , Sudáfrica/epidemiología , Esputo/microbiología , Tuberculosis/diagnóstico , Tuberculosis/tratamiento farmacológico , Tuberculosis/epidemiología
5.
Afr J Lab Med ; 11(1): 1482, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35747557

RESUMEN

Background: The 2017-2018 listeriosis outbreak in South Africa warranted testing for Listeria monocytogenes in food products and processing environments. Diagnostic tests are needed to accurately differentiate L. monocytogenes from other Listeria species. Objective: The study assessed the performance of the commonly used tests in our setting to accurately identify L. monocytogenes. Methods: The study was conducted in a public health laboratory in South Africa. Cultured isolates from food and environmental samples were tested both prospectively and retrospectively between August 2018 and December 2018. Isolates were phenotypically identified using tests for detecting ß-haemolysis, Christie-Atkins-Munch-Peterson, alanine arylamidase (AlaA), mannosidase, and xylose fermentation. Listeria monocytogenes isolates were identified using automated systems, Microscan Walkaway Plus 96, Vitek® MS, Vitek® 2 and Surefast Listeria monocytogenes PLUS PCR. All results were compared to whole-genome sequencing results. Results: ß-haemolysis and Christie-Atkins-Munch-Peterson tests gave delayed positivity or were negative for L. monocytogenes and falsely positive for one strain of Listeria innocua. The AlaA enzyme and Colorex Listeria agar lacked specificity for L. monocytogenes identification. Based on a few phenotypic test results, an aberrant L. monocytogenes strain and Listeria seeligeri strain were reported. All automated platforms overcalled L. monocytogenes in place of other Listeria species. Conclusion: No test was ideal in differentiating Listeria species. This is an issue in resource-limited settings where these tests are currently used. Newer technologies based on enzyme-linked immunosorbent assay and other molecular techniques specific to L. monocytogenes detection need to be investigated.

6.
Artículo en Inglés | MEDLINE | ID: mdl-36612608

RESUMEN

The use and abuse of antibiotics are directly related to the development of drug resistance, a global public health problem. Whereas the majority of research focus is on the use and misuse of antibiotics in drug resistance development, little is known about improper disposal, as a source of contamination in the environment that includes groundwater, especially in informal settlements. This study sought to determine antibiotic use and disposal in informal settlements in Kisumu, Kenya. A random cross-sectional sample of 447 households in selected informal settlements of Kisumu, Kenya was studied. A structured questionnaire was issued to persons heading households. The prevalence of antibiotic use was 43% (n = 193). Among these people, 74% (n = 144) had consulted a health worker in a healthcare facility for a prescription. Respondents did not always complete doses but kept the remainder for the next time they would become ill (54%). About 32% disposed of the remainder of the antibiotics in pit latrines and compost pits (10%) while 4% disposed through burning. Antibiotic use was fairly high despite a low level of awareness of the health effects of consuming water contaminated with antibiotics (35%) (n = 156); p = 0.03. Misuse and inappropriate disposal of antibiotics as identified may lead to a higher risk of antibiotic resistance, increasing the disease burden in the informal settlements.


Asunto(s)
Composición Familiar , Salud Pública , Humanos , Kenia/epidemiología , Prevalencia , Estudios Transversales
7.
Mutat Res ; 821: 111724, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33070028

RESUMEN

BACKGROUND: Mycobacterium tuberculosis (Mtb) is an airborne pathogenic microorganism that causes tuberculosis (TB). This pathogen invades lung tissues causing pulmonary infections and disseminates into other host organs. The Bacillus Calmette-Guérin (BCG) vaccine is employed to provide immune protection against TB; however, its efficacy is dependent on the age, immune status and geographic location of vaccinated individuals. Advanced diagnostic approaches such as GeneXpert MTB/RIF® and line probe assays (LPAs) have allowed rapid detection of drug-resistant, multidrug-resistant (MDR) and extensively drug-resistant (XDR) Mtb strains. However, in sub-Saharan Africa, public and private health institutions are further burdened by the high prevalence of Human Immunodeficiency Virus (HIV), the causative agent of acquired immunodeficiency syndrome (AIDS) and TB co-infections across different age groups. Epigenetic mechanisms have been widely exploited by Mtb and HIV to bypass the host's innate and adaptive immune responses, leading to microbial proliferation and disease manifestation. In the current study, we investigated the impact of epigenetic mechanisms in regulating target gene expression in healthy and patients co-infected with MDR TB-HIV.


Asunto(s)
Coinfección/genética , Epigénesis Genética , Infecciones por VIH/genética , VIH/aislamiento & purificación , Mycobacterium tuberculosis/aislamiento & purificación , Transcriptoma , Tuberculosis Resistente a Múltiples Medicamentos/genética , Adulto , Estudios de Casos y Controles , Coinfección/epidemiología , Coinfección/microbiología , Coinfección/virología , Femenino , VIH/genética , Infecciones por VIH/epidemiología , Infecciones por VIH/virología , Humanos , Masculino , Persona de Mediana Edad , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/genética , Fenotipo , Estándares de Referencia , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico , Tuberculosis Resistente a Múltiples Medicamentos/epidemiología , Tuberculosis Resistente a Múltiples Medicamentos/microbiología , Adulto Joven
8.
J Glob Antimicrob Resist ; 23: 232-242, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33045438

RESUMEN

OBJECTIVES: In this study, we examined the impact of epigenetic modifications on host gene functioning by assessing the expression of seven candidate genes in three separate groups including healthy, multidrug-resistant (MDR) TB-HIV co-infected and HIV-1 positive individuals. METHODS: Ten patients with MDR TB and HIV-1 co-infection on TB and HIV therapy and a cohort comprised of 10 newly diagnosed individuals with HIV-1 infection were recruited from the TB and HIV clinics at the Charlotte Maxeke Johannesburg Academic Hospital. Notably, the HIV-1 positive individuals were not placed on antiretroviral therapy (ART) at the time of recruitment and blood collection. A third group consisting of 10 healthy participants without MDR TB or HIV infection was recruited from the University of the Witwatersrand. Blood samples collected from all three cohorts were employed for extraction of plasma, total RNA and genomic DNA. RESULTS: Our data indicated that the expression of DNA methyltransferase 1 (DNMT1) and Ten-eleven translocation methylcytosine dioxygenase 1 (TET1) genes was significantly increased in HIV-1 positive patients and was lowest in MDR TB-HIV co-infected patients. By contrast, histone acetyltransferase (HAT), histone deacetylase (HDAC), protein tyrosine kinase (PtkA) and protein tyrosine phosphatase (PtpA) mRNA expression levels were substantially enhanced in HIV-1 infected and were lowest in healthy individuals. Conversely, Dicer expression levels were comparable among all three study groups. CONCLUSION: Promising preliminary data emanating from this investigation may potentially be used for generation of novel vaccines and therapeutic compounds capable of neutralising MDR TB-HIV and HIV-1 infection.


Asunto(s)
Infecciones por VIH , VIH-1 , Tuberculosis Resistente a Múltiples Medicamentos , Acetilación , Antituberculosos/uso terapéutico , Metilación de ADN , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , VIH-1/genética , Humanos , Oxigenasas de Función Mixta , Fosforilación , Proteínas Proto-Oncogénicas , Sudáfrica , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico
9.
N Engl J Med ; 382(7): 632-643, 2020 02 13.
Artículo en Inglés | MEDLINE | ID: mdl-32053299

RESUMEN

BACKGROUND: An outbreak of listeriosis was identified in South Africa in 2017. The source was unknown. METHODS: We conducted epidemiologic, trace-back, and environmental investigations and used whole-genome sequencing to type Listeria monocytogenes isolates. A case was defined as laboratory-confirmed L. monocytogenes infection during the period from June 11, 2017, to April 7, 2018. RESULTS: A total of 937 cases were identified, of which 465 (50%) were associated with pregnancy; 406 of the pregnancy-associated cases (87%) occurred in neonates. Of the 937 cases, 229 (24%) occurred in patients 15 to 49 years of age (excluding those who were pregnant). Among the patients in whom human immunodeficiency virus (HIV) status was known, 38% of those with pregnancy-associated cases (77 of 204) and 46% of the remaining patients (97 of 211) were infected with HIV. Among 728 patients with a known outcome, 193 (27%) died. Clinical isolates from 609 patients were sequenced, and 567 (93%) were identified as sequence type 6 (ST6). In a case-control analysis, patients with ST6 infections were more likely to have eaten polony (a ready-to-eat processed meat) than those with non-ST6 infections (odds ratio, 8.55; 95% confidence interval, 1.66 to 43.35). Polony and environmental samples also yielded ST6 isolates, which, together with the isolates from the patients, belonged to the same core-genome multilocus sequence typing cluster with no more than 4 allelic differences; these findings showed that polony produced at a single facility was the outbreak source. A recall of ready-to-eat processed meat products from this facility was associated with a rapid decline in the incidence of L. monocytogenes ST6 infections. CONCLUSIONS: This investigation showed that in a middle-income country with a high prevalence of HIV infection, L. monocytogenes caused disproportionate illness among pregnant girls and women and HIV-infected persons. Whole-genome sequencing facilitated the detection of the outbreak and guided the trace-back investigations that led to the identification of the source.


Asunto(s)
Brotes de Enfermedades , Enfermedades Transmitidas por los Alimentos/epidemiología , Listeria monocytogenes/aislamiento & purificación , Listeriosis/epidemiología , Productos de la Carne/microbiología , Adolescente , Adulto , Anciano , Técnicas de Tipificación Bacteriana , Estudios de Casos y Controles , Femenino , Enfermedades Transmitidas por los Alimentos/etiología , Enfermedades Transmitidas por los Alimentos/mortalidad , Infecciones por VIH/complicaciones , VIH-1 , Humanos , Recién Nacido , Listeria monocytogenes/genética , Listeriosis/etiología , Listeriosis/mortalidad , Masculino , Productos de la Carne/efectos adversos , Persona de Mediana Edad , Embarazo , Complicaciones Infecciosas del Embarazo/epidemiología , Recall y Retirada del Producto , Distribución por Sexo , Sudáfrica/epidemiología , Secuenciación Completa del Genoma , Adulto Joven
10.
Tuberculosis (Edinb) ; 113: 200-214, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30514504

RESUMEN

Tuberculosis (TB) infection caused by Mycobacterium tuberculosis (Mtb) is still a persistent global health problem, particularly in developing countries. The World Health Organization (WHO) reported a mortality rate of about 1.8 million worldwide due to TB complications in 2015. The Bacillus Calmette-Guérin (BCG) vaccine was introduced in 1921 and is still widely used to prevent TB development. This vaccine offers up to 80% protection against various forms of TB; however its efficacy against lung infection varies among different geographical settings. Devastatingly, the development of various forms of drug-resistant TB strains has significantly impaired the discovery of effective and safe anti-bacterial agents. Consequently, this necessitated discovery of new drug targets and novel anti-TB therapeutics to counter infection caused by various Mtb strains. Importantly, various factors that contribute to TB development have been identified and include bacterial resuscitation factors, host factors, environmental factors and genetics. Furthermore, Mtb-induced epigenetic changes also play a crucial role in evading the host immune response and leads to bacterial persistence and dissemination. Recently, the application of GeneXpert MTB/RIF® to rapidly diagnose and identify drug-resistant strains and discovery of different molecular markers that distinguish between latent and active TB infection has motivated and energised TB research. Therefore, this review article will briefly discuss the current TB state, highlight various mechanisms employed by Mtb to evade the host immune response as well as to discuss some modern molecular techniques that may potentially target and inhibit Mtb replication.


Asunto(s)
Farmacorresistencia Bacteriana/genética , Epigénesis Genética , Mycobacterium tuberculosis/genética , Tuberculosis/genética , Tuberculosis/microbiología , Animales , Antituberculosos/uso terapéutico , Genotipo , Humanos , Evasión Inmune/genética , Mutación , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/inmunología , Mycobacterium tuberculosis/patogenicidad , Fenotipo , Pronóstico , Tuberculosis/tratamiento farmacológico , Tuberculosis/inmunología , Vacunas contra la Tuberculosis/uso terapéutico
11.
Curr Opin Infect Dis ; 31(4): 316-324, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29846209

RESUMEN

PURPOSE OF REVIEW: Less than two decades into the 21st century, the world has already witnessed numerous large epidemics or pandemics. These events have highlighted inadequacies in both national and international capacity for outbreak prevention, detection, and response. Here, we review some of the major challenges from a policy perspective. RECENT FINDINGS: The most important challenges facing policymakers include financing outbreak preparedness and response in a complex political environment with limited resources, coordinating response efforts among a growing and diverse range of national and international actors, accurately assessing national outbreak preparedness, addressing the shortfall in the global biomedical workforce, building surge capacity of both human and material resources, balancing investments in public health and curative services, building capacity for outbreak-related research and development, and reinforcing measures for infection prevention and control. SUMMARY: In recent years, numerous epidemics and pandemics have caused not only considerable loss of life but also billions of dollars of economic loss. Although the events have served as a wake-up call and led to the implementation of relevant policies and counter-measures, such as the Global Health Security Agenda, many questions remain and much work to be done. Wise policies and approaches for outbreak control exist, but will require the political will to implement them.


Asunto(s)
Epidemias/prevención & control , Planificación en Salud , Pandemias/prevención & control , Epidemias/economía , Epidemias/legislación & jurisprudencia , Salud Global , Planificación en Salud/legislación & jurisprudencia , Planificación en Salud/métodos , Política de Salud , Fuerza Laboral en Salud , Humanos , Control de Infecciones , Pandemias/economía , Pandemias/legislación & jurisprudencia , Investigación
12.
J Infect Dev Ctries ; 12(8): 616-624, 2018 08 31.
Artículo en Inglés | MEDLINE | ID: mdl-31958323

RESUMEN

INTRODUCTION: Antimicrobial resistant bacterial infections are widespread globally and increases in antimicrobial resistance presents a major threat to public health. Pseudomonas aeruginosa is an opportunistic healthcare-associated pathogen with high rates of morbidity and mortality and an extensive range of resistance mechanisms. This study describes the antibiotic susceptibility profiles of P. aeruginosa isolates from patients with bacteraemia submitted by sentinel laboratories in South Africa from 2014 to 2015. METHODOLOGY: Organism identification and antimicrobial susceptibility testing were done using automated systems. Molecular methods were used to detect common resistance genes and mechanisms. RESULTS: Overall the susceptibility was high for all antibiotics tested with a decrease over the two-year period. There was no change in the MIC50 and MIC90 breakpoints for all antibiotics from 2014 to 2015. The MIC50 was within the susceptible breakpoint range for most antibiotics and the MIC90 was within the susceptible breakpoint range for colistin only. Phenotypically carbapenem non-susceptible isolates harboured the following plasmid-mediated genes: blaVIM (n = 81, 12%) and blaGES (n = 6, 0.9%); blaNDM (n = 4, 0.6%) and blaOXA-48 and variants (n = 3, 0.45%). Porin deletions were observed in one meropenem non-susceptible isolate only, and multi-drug resistance efflux pumps were expressed in the majority of the non-susceptible isolates investigated. BlaVEB-1, blaIMP and blaKPC were not detected. CONCLUSION: The prevalence of resistance to commonly used antibacterial agents was low for P. aeruginosa isolates and similarly, tested resistance mechanisms were detected in a relatively small proportion of isolates. Findings in this study represent baseline information for understanding antimicrobial susceptibility patterns in P. aeruginosa isolates from blood. Our surveillance report may assist in contributing to hospital treatment guidelines.


Asunto(s)
Antibacterianos/farmacología , Bacteriemia/microbiología , Infecciones por Pseudomonas/microbiología , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Proteínas Bacterianas/genética , Niño , Preescolar , Farmacorresistencia Bacteriana/efectos de los fármacos , Farmacorresistencia Bacteriana/genética , Femenino , Humanos , Lactante , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Infecciones por Pseudomonas/sangre , Infecciones por Pseudomonas/epidemiología , Pseudomonas aeruginosa/aislamiento & purificación , Sudáfrica/epidemiología , Adulto Joven , beta-Lactamasas/genética
13.
Int J Infect Dis ; 64: 100-106, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28893672

RESUMEN

The Global Action Plan on antimicrobial resistance calls for the use of antimicrobial medicines in human and animal health to be optimized, in tandem with a strengthening of the knowledge and evidence base through surveillance and research. However, there is a paucity of consumption data for African countries such as South Africa. Determining antimicrobial consumption data in low-resource settings remains a challenge. This article describes alternative mechanisms of assessing antimicrobial consumption data, such as the use of Intercontinental Marketing Services (IMS) data and contract data arising from tenders (an open Request for Proposal, RFP), as opposed to the international norms of daily defined doses per 100 patient-days or per 1000 population. Despite their limitations, these serve as indicators of antimicrobial exposure at the population level and represent an alternative method for ascertaining antimicrobial consumption in human health. Furthermore, South Africa has the largest antiretroviral treatment programme globally and carries a high burden of tuberculosis. This prompted the inclusion of antiretroviral and anti-tuberculosis antibiotic consumption data. Knowledge of antimicrobial utilization is imperative for meaningful future interventions. Baseline antimicrobial utilization data could guide future research initiatives that could provide a better understanding of the different measures of antibiotic use and the level of antibiotic resistance.


Asunto(s)
Antiinfecciosos/uso terapéutico , Farmacorresistencia Microbiana , Control de Medicamentos y Narcóticos , Animales , Antibacterianos/administración & dosificación , Antibacterianos/uso terapéutico , Antiinfecciosos/administración & dosificación , Programas de Optimización del Uso de los Antimicrobianos , Antituberculosos/administración & dosificación , Antituberculosos/uso terapéutico , Antivirales/administración & dosificación , Antivirales/uso terapéutico , Humanos , Sudáfrica
14.
BMC Infect Dis ; 17(1): 104, 2017 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-28143441

RESUMEN

BACKGROUND: The diagnosis of tuberculous meningitis (TBM) can be extremely difficult in the absence of culture confirmation. Cerebrospinal fluid (CSF) adenosine deaminase (ADA) can potentially assist in this regard, although its current value remains unclear. The literature on the usefulness of CSF ADA in TBM diagnosis is inconsistent, especially from an analytical point of view. METHODS: A retrospective analysis of clinical and laboratory data relating to all CSF ADA requests during 2009 and 2010 in a South African quaternary healthcare setting was performed. A CSF ADA cut-off for TBM diagnosis was calculated using receiver operating characteristic curve analysis. The performance of CSF ADA in different infective and non-infective categories was assessed. RESULTS: In total, 3548 CSF ADA requests were considered over the 2-year period. Of these, 1490 were for patients for whom both a CSF ADA and a mycobacterial culture were requested. The optimal cut-off was calculated at 2.0 U/L (AUC = 0.86; 95% CI = 0.82 - 0.89; p-value < 0.01; sensitivity of 85.9% (95% CI of 77.0 - 92.3) and specificity of 77.7% (95% CI of 75.4 - 79.8%); positive likelihood ratio = 3.85 and negative likelihood ratio = 0.18). At this cut-off 13 TBM cases were missed. CONCLUSION: An optimal cut-off for routine use could not be established as too many TBM cases were missed. Specimen integrity, lack of ADA assay standardisation and overlap in performance of the assay in different diagnostic categories affect interpretation.


Asunto(s)
Adenosina Desaminasa/líquido cefalorraquídeo , Tuberculosis Meníngea/diagnóstico , Adulto , Femenino , Humanos , Masculino , Curva ROC , Estudios Retrospectivos , Sensibilidad y Especificidad , Tuberculosis Meníngea/líquido cefalorraquídeo
15.
Medchemcomm ; 8(12): 2195-2207, 2017 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-30108736

RESUMEN

The occurrence of invasive fungal diseases, particularly in immunocompromised patients, is life-threatening and increases the economic burden. The rising problem of multi-drug resistance is becoming a major concern for clinicians. In addition, a repertoire of antifungal agents is far less in number than antibacterial drugs. To combat these problems, combination therapy has gained a lot of interest. We previously reported the synergistic interaction of some mono- and bis-dihydropyrimidinone and thione derivatives with fluconazole and amphotericin B for combination antifungal therapy. In this study we used the same approach and synthesized different azole and non-azole derivatives of mono-(M) and bis-(B) chalcones and evaluated their antifungal activity profile alone and in combination with the most commonly used antifungal drug - fluconazole (FLC) - against seven FLC susceptible and three FLC resistant clinically isolated Candida albicans strains. Based on the minimum inhibitory concentration results, the bis-derivatives showed lower MIC values compared to their mono-analogues. Both fractional inhibitory concentration index and isobologram results revealed mostly synergistic, additive or indifferent interactions between the tested compounds and FLC against different Candida isolates. None of the tested compounds showed any effect on energy dependent R6G efflux, revealing that they do not reverse the mechanism of drug efflux. However, surprisingly, these compounds profoundly decreased ergosterol biosynthesis and showed down regulation of ERG11 gene expression, which is the possible mechanism of reversal of azole drug resistance by these compounds. These results provide a platform for further research to develop pyrimidinone/thione ring containing compounds as promising new antifungal agents, which could be used in antifungal combination therapy.

16.
Future Microbiol ; 10(10): 1629-34, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26437762

RESUMEN

Healthcare-associated infections have serious implications for both patients and hospitals. Environmental surface contamination is the key to transmission of nosocomial pathogens. Routine manual cleaning and disinfection eliminates visible soil and reduces environmental bioburden and risk of transmission, but may not address some surface contamination. Automated area decontamination technologies achieve more consistent and pervasive disinfection than manual methods, but it is challenging to demonstrate their efficacy within a randomized trial of the multiple interventions required to reduce healthcare-associated infection rates. Until data from multicenter observational studies are available, automated area decontamination technologies should be an adjunct to manual cleaning and disinfection within a total, multi-layered system and risk-based approach designed to control environmental pathogens and promote patient safety.


Asunto(s)
Infección Hospitalaria/epidemiología , Desinfección/métodos , Contaminación de Equipos/prevención & control , Control de Infecciones/métodos , Consenso , Infección Hospitalaria/microbiología , Exposición a Riesgos Ambientales , Humanos , Seguridad del Paciente
17.
J Water Health ; 13(1): 190-202, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25719478

RESUMEN

Mycobacterium kansasii (M. kansasii) is a major cause of non-tuberculous mycobacterial pulmonary disease in the South African gold-mining workforce, but the source of infection and molecular epidemiology are unknown. This study investigated the presence of M. kansasii in gold and coal mine and associated hostel water supplies and compared the genetic diversity of clinical and environmental isolates of M. kansasii. Five M. kansasii and ten other potentially pathogenic mycobacteria were cultured mainly from showerhead biofilms. Polymerase chain reaction-restriction analysis of the hsp65 gene on 196 clinical and environmental M. kansasii isolates revealed 160 subtype I, eight subtype II and six subtype IV strains. Twenty-two isolates did not show the typical M. kansasii restriction patterns, suggesting that these isolates may represent new subtypes of M. kansasii. In contrast to the clonal population structure found amongst the subtype I isolates from studies in other countries, DNA fingerprinting of 114 clinical and three environmental subtype I isolates demonstrated genetic diversity amongst the isolates. This study demonstrated that showerheads are possible sources of M. kansasii and other pathogenic non-tuberculous mycobacterial infection in a gold-mining region, that subtype I is the major clinical isolate of M. kansasii strain and that this subtype exhibits genetic diversity.


Asunto(s)
Oro , Minería , Infecciones por Mycobacterium no Tuberculosas/microbiología , Mycobacterium kansasii/aislamiento & purificación , Contaminantes del Agua/aislamiento & purificación , Biopelículas , ADN Bacteriano/genética , Genes Bacterianos/genética , Humanos , Mycobacterium kansasii/genética , Filogenia , Reacción en Cadena de la Polimerasa , Sudáfrica
18.
PLoS One ; 10(12): e0145429, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26719975

RESUMEN

INTRODUCTION: We aimed to obtain an in-depth understanding on recent antimicrobial resistance trends and molecular epidemiology trends of S. aureus bacteraemia (SAB). METHODS: Thirteen academic centres in South Africa were included from June 2010 until July 2012. S. aureus susceptibility testing was performed on the MicroScan Walkaway. Real-time PCR using the LightCycler 480 II was done for mecA and nuc. SCCmec and spa-typing were finalized with conventional PCR. We selected one isolate per common spa type per province for multilocus sequence typing (MLST). RESULTS: S. aureus from 2709 patients were included, and 1231 (46%) were resistant to methicillin, with a significant decline over the three-year period (p-value = 0.003). Geographical distribution of MRSA was significantly higher in Gauteng compared to the other provinces (P<0.001). Children <5 years were significantly associated with MRSA with higher rates compared to all other age groups (P = 0.01). The most prevalent SCCmec type was SCCmec type III (531 [41%]) followed by type IV (402 [31%]). Spa-typing discovered 47 different spa-types. The five (87%) most common spa-types were t037, t1257, t045, t064 and t012. Based on MLST, the commonest was ST612 clonal complex (CC8) (n = 7) followed by ST5 (CC5) (n = 4), ST36 (CC30) (n = 4) and ST239 (CC8) (n = 3). CONCLUSIONS: MRSA rate is high in South Africa. Majority of the isolates were classified as SCCmec type III (41%) and type IV (31%), which are typically associated with hospital and community- acquired infections, respectively. Overall, this study reveals the presence of a variety of hospital-acquired MRSA clones in South Africa dominance of few clones, spa 037 and 1257. Monitoring trends in resistance and molecular typing is recommended to detect changing epidemiological trends in AMR patterns of SAB.


Asunto(s)
Bacteriemia/epidemiología , Resistencia a la Meticilina , Staphylococcus aureus Resistente a Meticilina/fisiología , Infecciones Estafilocócicas/epidemiología , Adolescente , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Bacteriemia/microbiología , Niño , Preescolar , Genotipo , Hospitalización , Humanos , Lactante , Recién Nacido , Concentración 50 Inhibidora , Staphylococcus aureus Resistente a Meticilina/genética , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Epidemiología Molecular , Reacción en Cadena de la Polimerasa , Vigilancia de la Población , Prevalencia , Sudáfrica/epidemiología , Infecciones Estafilocócicas/microbiología , Adulto Joven
19.
PLoS Negl Trop Dis ; 8(11): e3233, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25393244

RESUMEN

BACKGROUND: In 2008 a nosocomial outbreak of five cases of viral hemorrhagic fever due to a novel arenavirus, Lujo virus, occurred in Johannesburg, South Africa. Lujo virus is only the second pathogenic arenavirus, after Lassa virus, to be recognized in Africa and the first in over 40 years. Because of the remote, resource-poor, and often politically unstable regions where Lassa fever and other viral hemorrhagic fevers typically occur, there have been few opportunities to undertake in-depth study of their clinical manifestations, transmission dynamics, pathogenesis, or response to treatment options typically available in industrialized countries. METHODS AND FINDINGS: We describe the clinical features of five cases of Lujo hemorrhagic fever and summarize their clinical management, as well as providing additional epidemiologic detail regarding the 2008 outbreak. Illness typically began with the abrupt onset of fever, malaise, headache, and myalgias followed successively by sore throat, chest pain, gastrointestinal symptoms, rash, minor hemorrhage, subconjunctival injection, and neck and facial swelling over the first week of illness. No major hemorrhage was noted. Neurological signs were sometimes seen in the late stages. Shock and multi-organ system failure, often with evidence of disseminated intravascular coagulopathy, ensued in the second week, with death in four of the five cases. Distinctive treatment components of the one surviving patient included rapid commencement of the antiviral drug ribavirin and administration of HMG-CoA reductase inhibitors (statins), N-acetylcysteine, and recombinant factor VIIa. CONCLUSIONS: Lujo virus causes a clinical syndrome remarkably similar to Lassa fever. Considering the high case-fatality and significant logistical impediments to controlled treatment efficacy trials for viral hemorrhagic fever, it is both logical and ethical to explore the use of the various compounds used in the treatment of the surviving case reported here in future outbreaks. Clinical observations should be systematically recorded to facilitate objective evaluation of treatment efficacy. Due to the risk of secondary transmission, viral hemorrhagic fever precautions should be implemented for all cases of Lujo virus infection, with specialized precautions to protect against aerosols when performing enhanced-risk procedures such as endotracheal intubation.


Asunto(s)
Antivirales/uso terapéutico , Infecciones por Arenaviridae/patología , Infección Hospitalaria/patología , Brotes de Enfermedades , Fiebres Hemorrágicas Virales/patología , Lujo virus/aislamiento & purificación , Acetilcisteína/uso terapéutico , Adulto , Infecciones por Arenaviridae/tratamiento farmacológico , Infecciones por Arenaviridae/epidemiología , Infecciones por Arenaviridae/virología , Infección Hospitalaria/tratamiento farmacológico , Infección Hospitalaria/epidemiología , Infección Hospitalaria/virología , Factor VIIa/uso terapéutico , Resultado Fatal , Femenino , Fiebres Hemorrágicas Virales/tratamiento farmacológico , Fiebres Hemorrágicas Virales/epidemiología , Fiebres Hemorrágicas Virales/virología , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Fiebre de Lassa/patología , Virus Lassa/aislamiento & purificación , Lujo virus/efectos de los fármacos , Masculino , Persona de Mediana Edad , Proteínas Recombinantes/uso terapéutico , Ribavirina/uso terapéutico , Sudáfrica/epidemiología
20.
S Afr Med J ; 104(8): 563-8, 2014 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-25213849

RESUMEN

BACKGROUND: The increasing rates of antimicrobial resistance observed in the nosocomial pathogen Klebsiella pneumoniae are of major public health concern worldwide. OBJECTIVES: To describe the antibiotic susceptibility profiles of K. pneumoniae isolates from bacteraemic patients submitted by sentinel laboratories in five regions of South Africa from mid-2010 to mid-2012. Molecular methods were used to detect the most commonly found extended-spectrum beta-lactamase (ESBL) and carbapenemase resistance genes. METHODS: Thirteen academic centres serving the public healthcare sector in Gauteng, KwaZulu-Natal, Free State, Limpopo and Western Cape provinces submitted K. pneumoniae isolates from patients with bloodstream infections. Vitek 2 and MicroScan instruments were used for organism identification and susceptibility testing. Multiplex polymerase chain reactions (PCRs) were used to detect blaCTX-M, blaSHV and blaTEM genes in a proportion of the ESBL isolates. All isolates exhibiting reduced susceptibility to carbapenems were PCR tested for blaKPC and blaNDM-1 resistance genes. RESULTS: Overall, 68.3% of the 2,774 isolates were ESBL-positive, showing resistance to cefotaxime, ceftazidime and cefepime. Furthermore, 46.5% of all isolates were resistant to ciprofloxacin and 33.1% to piperacillin-tazobactam. The major ESBL genes were abundantly present in the sample analysed. Most isolates (95.5%) were susceptible to the carbapenems tested, and no isolates were positive for blaKPC or blaNDM-1. There was a trend towards a decrease in susceptibility to most antibiotics. CONCLUSION: The high proportion of ESBL-producing K. pneumoniae isolates observed, and the prevalence of ESBL genes, are of great concern. Our findings represent a baseline for further surveillance in SA, and can be used for policy and treatment decisions.


Asunto(s)
Klebsiella pneumoniae/efectos de los fármacos , Farmacorresistencia Bacteriana , Humanos , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Vigilancia de Guardia , Sudáfrica , beta-Lactamasas/genética
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...