Incidence and clinical and microbiological features of invasive and probable invasive streptococcal group A infections in children and adults in the Brussels-Capital Region, 2005-2020.

Assess the incidence, risk factors, clinical and microbiological features, and outcome of both probable invasive and invasive group A Streptococcus (GAS) infections in children and adults in the BrusselsCapital Region between 2005 and 2020. A retrospective, multicentric study was performed in three university hospitals in Brussels. Patients were identified through the centralized laboratory information system. Epidemiological and clinical data were collected from patients' hospital records. A total of 467 cases were identified. Incidence has increased from 2.1 to 10.9/100,000 inhabitants between 2009 and 2019 in non-homeless adults while it was above 100/100,000 on homeless in years with available denominators. Most of GAS were isolated from blood (43.6%), and the most common clinical presentation was skin and soft tissue infections (42.8%). A third of all the patients needed surgery, a quarter was admitted to the intensive care unit, and 10% of the adult patients died. Wounds and chickenpox disease were the main risk factors for children. Tobacco, alcohol abuse, wounds or chronic skin lesion, being homeless, and diabetes were identified as major predisposing factors for adults. The most common emm clusters were D4, E4, and AC3; 64% of the isolates were theoretically covered by the 30-valent M-protein vaccine. The burden of invasive and probable invasive GAS infections is on the rise in the studied adult population. We identified potential interventions that could contribute to decrease this burden: appropriate care of wounds, specifically among homeless and patients with risk factors such as diabetes and systematic chickenpox vaccination for children.

Detection of Herpesviridae in whole blood by multiplex PCR DNA-based microarray analysis after hematopoietic stem cell transplantation.

Viral infections are important causes of morbidity and mortality in patients after hematopoietic stem cell transplantation. The monitoring by PCR of Herpesviridae loads in blood samples has become a critical part of posttransplant follow-up, representing mounting costs for the laboratory. In this study, we assessed the clinical performance of the multiplex PCR DNA microarray Clart Entherpex kit for detection of cytomegalovirus (CMV), Epstein-Barr virus (EBV), and human herpesvirus 6 (HHV-6) as a screening test for virological follow-up. Two hundred fifty-five blood samples from 16 transplanted patients, prospectively tested by routine PCR assays, were analyzed by microarray. Routine PCR detected single or multiple viruses in 42% and 10% of the samples, respectively. Microarray detected single or multiple viruses in 34% and 18% of the samples, respectively. Microarray results correlated well with CMV and EBV detections by routine PCR (kappa tests = 0.79 and 0.78, respectively), whereas a weak correlation was observed with HHV-6 (0.43). HHV-7 was also detected in 48 samples by microarray. In conclusion, the microarray is a reliable screening assay for a posttransplant virological follow-up to detect CMV and EBV infections in blood. However, positive samples must be subsequently confirmed and viral loads must be quantified by PCR assays. Limitations were identified regarding HHV-6 detection. Although it is promising, is easy to use as a first-line test, and allows a reduction in the cost of analysis without undue delay in the reporting of the final quantitative result to the clinician, some characteristics of this microarray should be improved, particularly regarding quality control and the targeted virus panel, such that it could then be used as a routine test.

Impact of rapid molecular screening at hospital admission on nosocomial transmission of methicillin-resistant Staphylococcus aureus: cluster randomised trial.

DESIGN: Cluster randomised crossover trial with seven wards randomly allocated to intervention or control arm. SETTING: Medical and surgical wards of a university hospital with active MRSA control programme. PARTICIPANTS: All patients hospitalized >48 h in study wards and screened for MRSA on admission and discharge Intervention: Rapid PCR-based screening test for MRSA compared with control screening test by enrichment culture using chromogenic agar. OBJECTIVE: We determined the benefit of PCR-detection versus culture-based detection of MRSA colonisation upon patient admission on early implementation of isolation precautions and reduction of hospital transmission of MRSA. MAIN OUTCOME: Cumulative rate of MRSA hospital acquisition of in patients screened negative on admission. RANDOMIZATION: The sequential order of inclusion of study wards in each arm was randomised by assigning a number to each ward and using a computer generated list of random numbers. FINDINGS: Of 3704 eligible patients, 67.8% were evaluable for the study. Compared with culture, PCR-screening reduced the median test reporting time from admission from 88 to 11 hours (p<0.001) and the median time from admission to isolation from 96 to 25 hours (p<0.001). MRSA acquisition was detected in 36 patients (3.2%) in the control arm and 34 (3.2%) in the intervention arm. The incidence density rate of hospital acquired MRSA was 2.82 and 2.57/1,000 exposed patient-days in the control and intervention arm, respectively (risk ratio 0.91 (95% confidence interval, 0.60-1.39). Poisson regression model adjusted for colonisation pressure, compliance with hand hygiene and antibiotic use indicated a RR 0.99 (95% CI, 0.69 to 1.44). INTERPRETATION: Universal PCR screening for MRSA on admission to medical and surgical wards in an endemic setting shortened the time to implement isolation precautions but did not reduce nosocomial acquisition of MRSA. TRIAL REGISTRATION: clinicaltrials.gov NCT00846105.