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1.
Sci Rep ; 13(1): 19025, 2023 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-37923898

RESUMO

Hypervirulent Klebsiella pneumoniae strains (hvKp) can cause invasive community-acquired infections in healthy patients of all ages. In this study, the prevalence of putative hvKp in a German tertiary center was investigated and hvKp were characterized by phenotypic and molecular assays. All K. pneumoniae isolates in routine microbiological diagnostics from a single center were screened by string-testing over a period of 6 months. String-test positive (≥ 0.5 mm) isolates were re-evaluated on different media and under various conditions (aerobe, anaerobe). For string-test positive isolates, genes (magA, iutA, rmpA and rmpA2) associated with hypermucoviscosity and hypervirulence were amplified by multiplex PCR. PCR-positive isolates were subjected to whole-genome sequencing and sedimentation and biofilm formation assays. From 1310 screened K. pneumoniae isolates in clinical routine 100 isolates (7.6%) were string test positive. From these, 9% (n = 9) were defined as putative hvKp (string-test+/PCR+). Highest rate of string-test-positive isolates was observed on MacConkey agar under aerobic conditions. Amongst these nine putative hvKp isolates, the international lineage ST23 carrying hvKp-plasmid pKpVP-1 was the most common, but also a rare ST86 with pKpVP-2 was identified. All nine isolates showed hypermucoviscosity and weak biofilm formation. In conclusion, 9% of string-positive, respectively 0.69% of all K. pneumoniae isolates from routine were defined as putative hypervirulent. MacConkey agar was the best medium for hvKp screening.


Assuntos
Infecções por Klebsiella , Klebsiella pneumoniae , Humanos , Fatores de Virulência/genética , Virulência/genética , Ágar , Reação em Cadeia da Polimerase Multiplex , Infecções por Klebsiella/diagnóstico , Infecções por Klebsiella/epidemiologia , Infecções por Klebsiella/microbiologia , Antibacterianos
2.
J Infect ; 87(5): 428-437, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37549695

RESUMO

The objectives of this study were to assess Candida spp. distribution and antifungal resistance of candidaemia across Europe. Isolates were collected as part of the third ECMM Candida European multicentre observational study, conducted from 01 to 07-07-2018 to 31-03-2022. Each centre (maximum number/country determined by population size) included ∼10 consecutive cases. Isolates were referred to central laboratories and identified by morphology and MALDI-TOF, supplemented by ITS-sequencing when needed. EUCAST MICs were determined for five antifungals. fks sequencing was performed for echinocandin resistant isolates. The 399 isolates from 41 centres in 17 countries included C. albicans (47.1%), C. glabrata (22.3%), C. parapsilosis (15.0%), C. tropicalis (6.3%), C. dubliniensis and C. krusei (2.3% each) and other species (4.8%). Austria had the highest C. albicans proportion (77%), Czech Republic, France and UK the highest C. glabrata proportions (25-33%) while Italy and Turkey had the highest C. parapsilosis proportions (24-26%). All isolates were amphotericin B susceptible. Fluconazole resistance was found in 4% C. tropicalis, 12% C. glabrata (from six countries across Europe), 17% C. parapsilosis (from Greece, Italy, and Turkey) and 20% other Candida spp. Four isolates were anidulafungin and micafungin resistant/non-wild-type and five resistant to micafungin only. Three/3 and 2/5 of these were sequenced and harboured fks-alterations including a novel L657W in C. parapsilosis. The epidemiology varied among centres and countries. Acquired echinocandin resistance was rare but included differential susceptibility to anidulafungin and micafungin, and resistant C. parapsilosis. Fluconazole and voriconazole cross-resistance was common in C. glabrata and C. parapsilosis but with different geographical prevalence.

3.
J Antimicrob Chemother ; 78(9): 2185-2191, 2023 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-37473450

RESUMO

BACKGROUND: In recent years, an increasing number of linezolid-resistant enterococci (LRE) was recognized at the German National Reference Centre (NRC) for Enterococci. National guidelines on infection prevention recommend screening for LRE in epidemiologically linked hospital settings without referring to a reliable and rapid diagnostic method. Since 2020, CHROMAgar™ provide a chromogenic linezolid screening agar, LIN-R, suitable to simultaneously screen for linezolid-resistant staphylococci and enterococci. OBJECTIVES: To assess the applicability of CHROMAgar™ LIN-R in clinical settings for detecting LRE directly from patient material and to infer prevalence rates of LRE amongst German hospital patients. METHODS: During the 3-month trial period, clinical samples were plated on CHROMAgar™ LIN-R. Antimicrobial susceptibility testing was performed using VITEK2 or disc diffusion. At the NRC, linezolid resistance was determined by broth microdilution, multiplex-PCR for cfr/optrA/poxtA and by a restriction-based assay for 23S rDNA mutations. RESULTS: The 12 participating study sites used 13 963 CHROMAgar™ LIN-R plates during the study period. Of 442 presumptive LRE, 192 were confirmed by phenotypic methods. Of these, 161 were received by the NRC and 121 (75%) were verified as LRE. Most of LR-E. faecium 53/81 (65%) exhibited a 23S rRNA gene mutation as the sole resistance-mediating mechanism, whereas optrA constituted the dominant resistance trait in LR-E. faecalis [39/40 (98%)]. Prevalence of LRE across sites was estimated as 1% (ranging 0.18%-3.7% between sites). CONCLUSIONS: CHROMAgar™ LIN-R represents a simple and efficient LRE screening tool in hospital settings. A high proportion of false-positive results demands validation of linezolid resistance by a reference method.


Assuntos
Enterococcus faecium , Infecções por Bactérias Gram-Positivas , Humanos , Linezolida/farmacologia , Antibacterianos/farmacologia , Prevalência , Farmacorresistência Bacteriana/genética , Enterococcus/genética , Hospitais , Infecções por Bactérias Gram-Positivas/epidemiologia , Enterococcus faecium/genética , Testes de Sensibilidade Microbiana , Enterococcus faecalis
4.
J Fungi (Basel) ; 9(4)2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-37108955

RESUMO

With increasing frequency, clinical and laboratory-based mycologists are consulted on invasive fungal diseases caused by rare fungal species. This review aims to give an overview of the management of invasive aspergillosis (IA) caused by non-fumigatus Aspergillus spp.-namely A. flavus, A. terreus, A. niger and A. nidulans-including diagnostic and therapeutic differences and similarities to A. fumigatus. A. flavus is the second most common Aspergillus spp. isolated in patients with IA and the predominant species in subtropical regions. Treatment is complicated by its intrinsic resistance against amphotericin B (AmB) and high minimum inhibitory concentrations (MIC) for voriconazole. A. nidulans has been frequently isolated in patients with long-term immunosuppression, mostly in patients with primary immunodeficiencies such as chronic granulomatous disease. It has been reported to disseminate more often than other Aspergillus spp. Innate resistance against AmB has been suggested but not yet proven, while MICs seem to be elevated. A. niger is more frequently reported in less severe infections such as otomycosis. Triazoles exhibit varying MICs and are therefore not strictly recommended as first-line treatment for IA caused by A. niger, while patient outcome seems to be more favorable when compared to IA due to other Aspergillus species. A. terreus-related infections have been reported increasingly as the cause of acute and chronic aspergillosis. A recent prospective international multicenter surveillance study showed Spain, Austria, and Israel to be the countries with the highest density of A. terreus species complex isolates collected. This species complex seems to cause dissemination more often and is intrinsically resistant to AmB. Non-fumigatus aspergillosis is difficult to manage due to complex patient histories, varying infection sites and potential intrinsic resistances to antifungals. Future investigational efforts should aim at amplifying the knowledge on specific diagnostic measures and their on-site availability, as well as defining optimal treatment strategies and outcomes of non-fumigatus aspergillosis.

5.
Antibiotics (Basel) ; 11(5)2022 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-35625189

RESUMO

Multidrug resistance is an emerging healthcare issue, especially concerning Pseudomonas aeruginosa. In this multicenter study, P. aeruginosa isolates with resistance against meropenem detected by routine methods were collected and tested for carbapenemase production and susceptibility against ceftazidime-avibactam. Meropenem-resistant isolates of P. aeruginosa from various clinical materials were collected at 11 tertiary care hospitals in Germany from 2017−2019. Minimum inhibitory concentrations (MICs) were determined via microdilution plates (MICRONAUT-S) of ceftazidime-avibactam and meropenem at each center. Detection of the presence of carbapenemases was performed by PCR or immunochromatography. For meropenem-resistant isolates (n = 448), the MIC range of ceftazidime-avibactam was 0.25−128 mg/L, MIC90 was 128 mg/L and MIC50 was 16 mg/L. According to EUCAST clinical breakpoints, 213 of all meropenem-resistant P. aeruginosa isolates were categorized as susceptible (47.5%) to ceftazidime-avibactam. Metallo-ß-lactamases (MBL) could be detected in 122 isolates (27.3%). The MIC range of ceftazidime-avibactam in MBL-positive isolates was 4−128 mg/L, MIC90 was >128 mg/L and MIC50 was 32 mg/L. There was strong variation in the prevalence of MBL-positive isolates among centers. Our in vitro results support ceftazidime-avibactam as a treatment option against infections caused by meropenem-resistant, MBL-negative P. aeruginosa.

6.
J Infect Dis ; 226(9): 1608-1615, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-35512326

RESUMO

BACKGROUND: The contribution of droplet-contaminated surfaces for virus transmission has been discussed controversially in the context of the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) pandemic. More importantly, the risk of fomite-based transmission has not been systematically addressed. Therefore, the aim of this study was to evaluate whether confirmed hospitalized coronavirus disease 2019 (COVID-19) patients can contaminate stainless steel carriers by coughing or intensive moistening with saliva and to assess the risk of SARS-CoV-2 transmission upon detection of viral loads and infectious virus in cell culture. METHODS: We initiated a single-center observational study including 15 COVID-19 patients with a high baseline viral load (cycle threshold value ≤25). We documented clinical and laboratory parameters and used patient samples to perform virus culture, quantitative polymerase chain reaction, and virus sequencing. RESULTS: Nasopharyngeal and oropharyngeal swabs of all patients were positive for viral ribonucleic acid on the day of the study. Infectious SARS-CoV-2 could be isolated from 6 patient swabs (46.2%). After coughing, no infectious virus could be recovered, however, intensive moistening with saliva resulted in successful viral recovery from steel carriers of 5 patients (38.5%). CONCLUSIONS: Transmission of infectious SARS-CoV-2 via fomites is possible upon extensive moistening, but it is unlikely to occur in real-life scenarios and from droplet-contaminated fomites.


Assuntos
COVID-19 , Doenças Transmissíveis , Humanos , SARS-CoV-2 , Fômites , Pandemias , Carga Viral
7.
One Health Outlook ; 4(1): 9, 2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-35527255

RESUMO

BACKGROUND: The Equine Hepacivirus (EqHV) is an equine-specific and liver-tropic virus belonging to the diverse genus of Hepaciviruses. It was recently found in a large donkey (Equus asinus) cohort with a similar seroprevalence (30%), but lower rate of RNA-positive animals (0.3%) compared to horses. These rare infection events indicate either a lack of adaptation to the new host or a predominantly acute course of infection. METHODS: In order to analyze the susceptibility and the course of EqHV infection in donkeys, we inoculated two adult female donkeys and one control horse intravenously with purified EqHV from a naturally infected horse. Liver biopsies were taken before and after inoculation to study changes in the transcriptome. RESULTS: Infection kinetics were similar between the equids. All animals were EqHV PCR-positive from day three. EqHV RNA-levels declined when the animals seroconverted and both donkeys cleared the virus from the blood by week 12. Infection did not have an impact on the clinical findings and no significant histopathological differences were seen. Blood biochemistry revealed a mild increase in GLDH at the time of seroconversion in horses, which was less pronounced in donkeys. Transcriptomic analysis revealed a distinct set of differentially expressed genes, including viral host factors and immune genes. CONCLUSION: To summarize, our findings indicate that donkeys are a natural host of EqHV, due to the almost identical infection kinetics. The different immune responses do however suggest different mechanisms in reacting to hepaciviral infections.

8.
J Clin Med ; 11(3)2022 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-35160206

RESUMO

Septic arthritis is common in older adults and can be related to joint surgery or hematogenous distribution. To date, the risk factors affecting survival are unknown. This study aimed to evaluate the effects of existing implants, positive synovial microbiological culture results, and the American Society of Anesthesiology Physical Status (ASA) classification on the short- and mid-term survival of older patients with primary septic gonarthritis. This retrospective study included 133 older adults >60 years who underwent surgery for primary septic gonarthritis. Data were collected from medical records and public obituaries. Kaplan-Meier survival curves were used to estimate the probability of survival, as well as log-rank tests to measure and compare survival rates over one- and five-year periods. The mean age was 74.9 years (SD ± 9.2), and the 5-year follow-up rate was 74.3% (the mean follow-up was 3000.5 days; SD ± 1771.6). Mean survival was significantly different in patients with implants and without implants (p = 0.015), and between ASA II, ASA III, and ASA IV (p < 0.001). There was no significant difference in the survival of patients with or without a positive synovial microbiological culture (p = 0.08). Older adults with septic monoarthritis and pre-existing medical implants showed impaired survival. The ASA classification prior to surgery for primary septic monoarthritis can be helpful in identifying patients with poorer mid-term outcomes.

9.
Mycoses ; 65(2): 132-133, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35075748
10.
World J Pediatr ; 17(5): 484-494, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34415560

RESUMO

BACKGROUND: Healthcare workers are considered a particularly high-risk group during the coronavirus disease 2019 (COVID-19) pandemic. Healthcare workers in paediatrics are a unique subgroup: they come into frequent contact with children, who often experience few or no symptoms when infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and, therefore, may transmit the disease to unprotected staff. In Germany, no studies exist evaluating the risk of COVID-19 to healthcare workers in paediatric institutions. METHODS: We tested the staff at a large children's hospital in Germany for immunoglobulin (Ig) G antibodies against the nucleocapsid protein of SARS-CoV-2 in a period between the first and second epidemic wave in Germany. We used a questionnaire to assess each individual's exposure risk and his/her own perception of having already been infected with SARS-CoV-2. RESULTS: We recruited 619 participants from all sectors, clinical and non-clinical, constituting 70% of the entire staff. The seroprevalence of SARS-CoV-2 antibodies was 0.325% (95% confidence interval 0.039-1.168). Self-perceived risk of a previous SARS-CoV-2 infection decreased with age (odds ratio, 0.81; 95% confidence interval, 0.70-0.93). Having experienced symptoms more than doubled the odds of a high self-perceived risk (odds ratio, 2.18; 95% confidence interval, 1.59-3.00). There was no significant difference in self-perceived risk between men and women. CONCLUSIONS: Seroprevalence was low among healthcare workers at a large children's hospital in Germany before the second epidemic wave, and it was far from a level that confers herd immunity. Self-perceived risk of infection is often overestimated.


Assuntos
Atitude do Pessoal de Saúde , Atitude Frente a Saúde , COVID-19/sangue , COVID-19/epidemiologia , Pessoal de Saúde/psicologia , Imunoglobulina G/sangue , SARS-CoV-2/imunologia , Adulto , Feminino , Alemanha/epidemiologia , Hospitais Pediátricos , Humanos , Masculino , Pessoa de Meia-Idade , Medição de Risco , Estudos Soroepidemiológicos
11.
iScience ; 24(8): 102908, 2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34337354

RESUMO

The current severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has created a significant threat to global health. While respiratory aerosols or droplets are considered as the main route of human-to-human transmission, secretions expelled by infected individuals can also contaminate surfaces and objects, potentially creating the risk of fomite-based transmission. Consequently, frequently touched objects such as paper currency and coins have been suspected as potential transmission vehicle. To assess the risk of SARS-CoV-2 transmission by banknotes and coins, we examined the stability of SARS-CoV-2 and bovine coronavirus, as surrogate with lower biosafety restrictions, on these different means of payment and developed a touch transfer method to examine transfer efficiency from contaminated surfaces to fingertips. Although we observed prolonged virus stability, our results indicate that transmission of SARS-CoV-2 via contaminated coins and banknotes is unlikely and requires high viral loads and a timely order of specific events.

13.
GMS Hyg Infect Control ; 16: Doc13, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33796441

RESUMO

Introduction: Vancomycin-resistant Enterococcus faecium accounts for around 10-23% of nosocomial enterococcal infections and constitutes a relevant therapeutic problem due to its limited susceptibility to antibiotics. The resistance towards glycopeptide antibiotics is mediated by the so-called van genes. Currently, the most common resistance type in Germany is the vanB-type. Little data are available on the molecular epidemiology in Germany. Therefore, an epidemiological typing of Enterococcus faecium isolates with vanB-type resistance from two German hospitals in Essen and Nuremberg was performed. Two outbreaks and 104 sporadic cases were investigated. Methods: All 128 isolates with vanB-type resistance were collected between 2011-2012 and 2017-2018. They were characterized using multilocus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE). Results: ST 117 was the most common sequence type (ST) in both hospitals, especially since 2017. PFGE divided the isolates of this study into 68 PFGE types and showed a broad genetic diversity. Two epidemiologically assumed in-hospital outbreaks were genetically confirmed. Apart from that, in-hospital transmissions were rare events. Conclusion: The results obtained by MLST confirmed the previously described allocation of STs in Germany. PFGE showed a broad genetic diversity of vanB VRE between the two hospitals and also within each hospital. In-hospital transmissions were rare, but outbreaks did occur. Our data supports the strategy to screen and isolate patients in transmission events in order to detect monoclonality indicating a common source or hygiene mismanagement.

15.
J Fungi (Basel) ; 6(4)2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33271743

RESUMO

Pneumocystis jirovecii pneumonia is a difficult invasive infection to diagnose. Apart from microscopy of respiratory specimens, two diagnostic tests are increasingly used including real-time quantitative PCR (qPCR) of respiratory specimens, mainly in bronchoalveolar lavage fluids (BAL), and serum ß-1,3-d-glucan (BDG). It is still unclear how these two biomarkers can be used and interpreted in various patient populations. Here we analyzed retrospectively and multicentrically the correlation between BAL qPCR and serum BDG in various patient population, including mainly non-HIV patients. It appeared that a good correlation can be obtained in HIV patients and solid organ transplant recipients but no correlation can be observed in patients with hematologic malignancies, solid cancer, and systemic diseases. This observation reinforces recent data suggesting that BDG is not the best marker of PCP in non-HIV patients, with potential false positives due to other IFI or bacterial infections and false-negatives due to low fungal load and low BDG release.

16.
Appl Environ Microbiol ; 86(24)2020 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-33097507

RESUMO

Stenotrophomonas maltophilia is one of the most frequently isolated multidrug-resistant nosocomial opportunistic pathogens. It contributes to disease progression in cystic fibrosis (CF) patients and is frequently isolated from wounds, infected tissues, and catheter surfaces. On these diverse surfaces S. maltophilia lives in single-species or multispecies biofilms. Since very little is known about common processes in biofilms of different S. maltophilia isolates, we analyzed the biofilm profiles of 300 clinical and environmental isolates from Europe of the recently identified main lineages Sgn3, Sgn4, and Sm2 to Sm18. The analysis of the biofilm architecture of 40 clinical isolates revealed the presence of multicellular structures and high phenotypic variability at a strain-specific level. Further, transcriptome analyses of biofilm cells of seven clinical isolates identified a set of 106 shared strongly expressed genes and 33 strain-specifically expressed genes. Surprisingly, the transcriptome profiles of biofilm versus planktonic cells revealed that just 9.43% ± 1.36% of all genes were differentially regulated. This implies that just a small set of shared and commonly regulated genes is involved in the biofilm lifestyle. Strikingly, iron uptake appears to be a key factor involved in this metabolic shift. Further, metabolic analyses implied that S. maltophilia employs a mostly fermentative growth mode under biofilm conditions. The transcriptome data of this study together with the phenotypic and metabolic analyses represent so far the largest data set on S. maltophilia biofilm versus planktonic cells. This study will lay the foundation for the identification of strategies for fighting S. maltophilia biofilms in clinical and industrial settings.IMPORTANCE Microorganisms living in a biofilm are much more tolerant to antibiotics and antimicrobial substances than planktonic cells are. Thus, the treatment of infections caused by microorganisms living in biofilms is extremely difficult. Nosocomial infections (among others) caused by S. maltophilia, particularly lung infection among CF patients, have increased in prevalence in recent years. The intrinsic multidrug resistance of S. maltophilia and the increased tolerance to antimicrobial agents of its biofilm cells make the treatment of S. maltophilia infection difficult. The significance of our research is based on understanding the common mechanisms involved in biofilm formation of different S. maltophilia isolates, understanding the diversity of biofilm architectures among strains of this species, and identifying the differently regulated processes in biofilm versus planktonic cells. These results will lay the foundation for the treatment of S. maltophilia biofilms.


Assuntos
Biofilmes , Genes Bacterianos , Variação Genética , Stenotrophomonas maltophilia/fisiologia , Stenotrophomonas maltophilia/patogenicidade , Europa (Continente) , Perfilação da Expressão Gênica , Fenótipo , Proteólise , Stenotrophomonas maltophilia/genética , Virulência
17.
Euro Surveill ; 25(39)2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33006300

RESUMO

We found that a single nucleotide polymorphism (SNP) in the nucleoprotein gene of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) from a patient interfered with detection in a widely used commercial assay. Some 0.2% of the isolates in the EpiCoV database contain this SNP. Although SARS-CoV-2 was still detected by the other probe in the assay, this underlines the necessity of targeting two independent essential regions of a pathogen for reliable detection.


Assuntos
Betacoronavirus/genética , Técnicas de Laboratório Clínico , Infecções por Coronavirus/diagnóstico , Nucleoproteínas/genética , Pandemias , Pneumonia Viral/diagnóstico , Mutação Puntual , Polimorfismo de Nucleotídeo Único , RNA Viral/genética , Reação em Cadeia da Polimerase em Tempo Real , Proteínas Virais/genética , Sequência de Bases , Betacoronavirus/isolamento & purificação , COVID-19 , Teste para COVID-19 , Técnicas de Laboratório Clínico/métodos , Busca de Comunicante , Infecções por Coronavirus/virologia , Primers do DNA , Erros de Diagnóstico , Reações Falso-Negativas , Feminino , Genes Virais , Humanos , Pessoa de Meia-Idade , Nasofaringe/virologia , Nucleoproteínas/análise , Filogenia , Pneumonia Viral/virologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Romênia , SARS-CoV-2 , Doença Relacionada a Viagens , Proteínas Virais/análise
18.
Vaccines (Basel) ; 8(3)2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32679691

RESUMO

Severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2, a new member of the genus Betacoronavirus, is a pandemic virus, which has caused numerous fatalities, particularly in the elderly and persons with underlying morbidities. At present, there are no approved vaccines nor antiviral therapies available. The detection and quantification of SARS-CoV-2-neutralizing antibodies plays a crucial role in the assessment of the immune status of convalescent COVID-19 patients, evaluation of recombinant therapeutic antibodies, and the evaluation of novel vaccines. To detect SARS-CoV-2-neutralizing antibodies, classically, a virus-neutralization test has to be performed at biosafety level 3, considerably limiting the general use of this test. In the present work, a biosafety level 1 pseudotype virus assay based on a propagation-incompetent vesicular stomatitis virus (VSV) has been used to determine the neutralizing antibody titers in convalescent COVID-19 patients. The neutralization titers in serum of two independently analyzed patient cohorts were available within 18 h and correlated well with those obtained with a classical SARS-CoV-2 neutralization test (Pearson correlation coefficients of r = 0.929 and r = 0.939, respectively). Most convalescent COVID-19 patients had only low titers of neutralizing antibodies (ND50 < 320). The sera of convalescent COVID-19 patients also neutralized pseudotype virus displaying the SARS-CoV-1 spike protein on their surface, which is homologous to the SARS-CoV-2 spike protein. In summary, we report a robust virus-neutralization assay, which can be used at low biosafety level 1 to rapidly quantify SARS-CoV-2-neutralizing antibodies in convalescent COVID-19 patients and vaccinated individuals.

19.
J Infect Dis ; 222(8): 1289-1292, 2020 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-32726430

RESUMO

The ongoing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic creates a significant threat to global health. Recent studies suggested the significance of throat and salivary glands as major sites of virus replication and transmission during early coronavirus disease 2019, thus advocating application of oral antiseptics. However, the antiviral efficacy of oral rinsing solutions against SARS-CoV-2 has not been examined. Here, we evaluated the virucidal activity of different available oral rinses against SARS-CoV-2 under conditions mimicking nasopharyngeal secretions. Several formulations with significant SARS-CoV-2 inactivating properties in vitro support the idea that oral rinsing might reduce the viral load of saliva and could thus lower the transmission of SARS-CoV-2.


Assuntos
Antivirais/farmacologia , Betacoronavirus/efeitos dos fármacos , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/virologia , Antissépticos Bucais/farmacologia , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/virologia , Animais , Betacoronavirus/fisiologia , COVID-19 , Chlorocebus aethiops , Infecções por Coronavirus/transmissão , Humanos , Pandemias , Pneumonia Viral/transmissão , SARS-CoV-2 , Saliva/virologia , Células Vero , Carga Viral/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos
20.
J Clin Microbiol ; 58(9)2020 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-32434781

RESUMO

Diagnosis of Lyme neuroborreliosis (LNB) is challenging, as long as Borrelia-specific intrathecal antibodies are not yet detectable. The chemokine CXCL13 is elevated in the cerebrospinal fluid (CSF) of LNB patients. Here, we compared the performances of the Euroimmun CXCL13 enzyme-linked immunosorbent assay (CXCL13 ELISA) and the ReaScan CXCL13 lateral flow immunoassay (CXCL13 LFA), a rapid point-of-care test, to support the diagnosis of LNB. In a dual-center case-control study, CSF samples from 90 patients (34 with definite LNB, 10 with possible LNB, and 46 with other central nervous system [CNS] diseases [non-LNB group]) were analyzed with the CXCL13 ELISA and the CXCL13 LFA. Classification of patients followed the European Federation of Neurological Societies (EFNS) guidelines on LNB. The CXCL13 ELISA detected elevated CXCL13 levels in all patients with definite LNB (median, 1,409 pg/ml) compared to the non-LNB controls (median, 20.7 pg/ml; P < 0.0001), with a sensitivity of 100% and a specificity of 84.8% (cutoff value, 78.6 pg/ml; area under the receiver operating characteristic [ROC] curve, 0.93). Similarly, the CXCL13 LFA yielded elevated CXCL13 levels in 31 patients with definite LNB (median arbitrary value, 223.5) compared to the non-LNB control patients (median arbitrary value, 0; P < 0.0001) and had a sensitivity and specificity of 91.2% and 93.5%, respectively (cutoff arbitrary value, 22.5; area under the ROC curve, 0.94). The correlation between the CXCL13 levels obtained by ELISA and LFA was strong (Spearman correlation coefficient r = 0.89; P < 0.0001). The CXCL13 ELISA and the CXCL13 LFA are comparable diagnostic tools for the detection of CXCL13 in the CSF of patients with definite LNB. The advantage of the CXCL13 LFA is the shorter time to result.


Assuntos
Neuroborreliose de Lyme , Estudos de Casos e Controles , Quimiocina CXCL13 , Ensaio de Imunoadsorção Enzimática , Humanos , Imunoensaio , Neuroborreliose de Lyme/diagnóstico
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