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Prevalence of invasive ß-haemolytic streptococci (BHS) at a tertiary care hospital and molecular diversity of S. pyogenes and S. dysgalactiae was studied. Between 2012 and 2016, all blood culture sets (n = 55,839), CSF (n = 8413) and soft tissue (n = 20,926) samples were analysed for BHS positivity using HYBASE software. Molecular profiles of 99 S. pyogenes and S. dysgalactiae were identified by sequencing of M protein genes (emm types) and multiplex PCR typing of 20 other virulence determinants. Streptococci contributed to 6.2% of blood, 10.7% of CSF and 14.5% of soft tissue isolates, being among the most common invasive isolates. The overall rates of invasive S. pyogenes, S. agalactiae, S. dysgalactiae and S. pneumoniae were 2.4, 4.4, 2.1, and 5.3%. Whereas S. pneumoniae was 1.5% more common in CSF samples, BHS isolates were 2-fold and 11-fold higher in bacteraemia and invasive soft tissue infections. Genetic BHS typing revealed wide molecular diversity of invasive and noninvasive group A and group G BHS, whereas one emm-type (stG62647.0) and no other virulence determinants except scpA were detected in invasive group C BHS. BHS were important invasive pathogens, outpacing S. pneumoniae in bacteraemia and invasive soft tissue infections. The incidence of S. dysgalactiae infections was comparable to that of S. pyogenes even with less diversity of molecular virulence. The results of this study emphasise the need for awareness of BHS invasiveness in humans and the need to develop BHS prevention strategies.

Symptoms of acute febrile respiratory tract infection are often unspecific, but the rapid identification of pathogens allows optimised patient management. The objective of this study was to evaluate a novel multiplex polymerase chain reaction (PCR) suspension microarray which detects 19 viral and four atypical bacterial targets. A comprehensive set of sensitive monoplex real-time PCR assays was used for each pathogen as the gold standard. A panel of archived as well as 300 prospectively collected clinical samples was analysed by both methods. At least one target was detected in 165/300 (55 %) samples by monoplex PCR and in 140/300 (46 %) samples by multiplex PCR, respectively. The positivity rate was significantly higher in paediatric patients compared to adults [126/154 (82 %) vs. 39/146 (27 %) by monoplex and 114/154 (74 %) vs. 26/146 (18 %) by multiplex PCR, respectively]. Among all samples, 17/300 (5.6 %) were positive for atypical bacteria by monoplex and 8/300 (2.6 %) by multiplex PCR, respectively. Multiple detections were recorded in 35/300 (11.6 %) samples by monoplex and 26/300 (8.7 %) by multiplex PCR. For the most common pathogens, the sensitivity ranged from 57 to 93 % and the specificity ranged from 95 to 100 %. The overall concordance between both methods was 77 % [95 % confidence interval (CI) 72-81 %]. False-negative results by multiplex PCR were mainly due to the low target concentration. Compared to monoplex PCR, the novel microarray assay proved its principle but displayed overall lower sensitivities, potentially restricting its use to paediatric patients. For some targets, only small numbers of positive samples were available, requiring larger studies to firmly assess the sensitivity and specificity.

The purpose of this paper was to present the current knowledge on the prevention of group B streptococcus (GBS) neonatal infections and the status of prevention policies in European countries and to present the DEVANI pan-European program, launched in 2008. The aim of this program was to assess the GBS neonatal infection burden in Europe, to design a new vaccine to immunize neonates against GBS infections, to improve the laboratory performance for the diagnosis of GBS colonization and infection, and to improve the methods for the typing of GBS strains. The current guidelines for GBS prevention in different countries were ascertained and a picture of the burden before and after the instauration of prevention policies has been drawn. After the issue of the Centers for Disease Control and Prevention (CDC) guidelines, many European countries have adopted universal screening for the GBS colonization of pregnant women and intrapartum prophylaxis to colonized mothers. Nevertheless, some European countries continue advocating the risk factor approach to GBS prevention. Most European countries have implemented policies to prevent GBS neonatal infections and the burden of the disease has decreased during the last several years. Nevertheless, further steps are necessary in order to develop new strategies of prevention, to improve microbiological techniques to detect GBS colonization and infection, and to coordinate the prevention policies in the EU.

Group A streptococcus (GAS) is considered to be a major pathogen of bacterial tonsillopharyngitis in children. Although GAS is generally susceptible to penicillin, macrolides are often used as the second-line treatment. Over the last several decades, the rising macrolide resistance of GAS has been detected in several countries. With the current study, we aimed to determine the development of macrolide resistance at our paediatric centre. From March 2006 to May 2009, 350 GAS isolates were tested for susceptibility to erythromycin, azithromycin, clindamycin, penicillin and cefotaxime. Macrolide-resistant isolates were screened for the presence of genes related to macrolide resistance (mefA, ermB, ermTR, prtF1). In comparison to a prior study at our hospital, the erythromycin resistance rate decreased significantly from 13.6 to 2.6%. This effect may be attributable to a more restrictive use of macrolides in children in our region.

The aim of the present study was to identify released proteins of Streptococcus agalactiae and to investigate their immunoreactivity with human sera to determine whether such proteins might be viable as carrier proteins in conjugate vaccines. Infections with S. agalactiae are the leading cause of sepsis and meningitis in neonates. Vaccination of women of childbearing age would be a desirable alternative to intrapartum antibiotic prophylaxis, but factors that mediate S. agalactiae invasive disease and virulence are poorly defined. Capsule-based vaccines have shown only low immunogenicity to date, and interest has shifted towards S. agalactiae proteins, either as candidate vaccine antigens or as carrier proteins for serotype-specific S. agalactiae polysaccharides. In this study, some major released proteins of S. agalactiae could be identified, including molecules known to be present on the surface of bacterial cells but not previously described as released proteins, such as CAMP factor, a phosphocarrier protein, aldolase, enolase, PcsB, and heat-shock protein 70. Serotype-specific differences in the protein patterns of extracellular products and immunoreactivity with human sera could be detected by SDS-PAGE and Western blot. The identification of unexpected released proteins may indicate secondary functions for these proteins. In addition, the widespread immunoreactivity of these proteins with human sera as shown by Western blot indicates that released proteins may be promising candidates as carrier proteins in conjugate vaccines.

Rapid antigen detection tests (RADT) are widely used for the rapid diagnosis of group A streptococcal (GAS) tonsillopharyngitis. In a prospective 3-year study, the reliability of two different RADT methods was compared, as performed by lab technicians versus physicians. Sensitivity and specificity, as well as positive and negative predictive values, were calculated. When performed by physicians, the results (44.4 %, 8.3 %, 26.7 % and 16.7 %) of a latex agglutination test (LAT) were unacceptably low. However, after switching to a lateral-flow immunoassay (LFIT) and implementing additional hands-on training, the performance improved dramatically (100 %, 92.6 %, 84.6 % and 100 %). In conclusion, technical errors, along with a lack of experience and expertise, negatively impact RADT accuracy.

Viral pathogens such as respiratory syncytial virus, human metapneumovirus, rhinovirus, adenovirus, parainfluenza virus and influenza virus are the most frequent causes of acute respiratory tract infection and hospitalization in infants and young children. However, no pathogen can be identified in about 30% of suspected respiratory infections [1]. Recently, a new human virus belonging to the Bocavirus genus of the subfamily Parvovirinae was cloned from pooled human respiratory samples and its pathogenic potential was proposed according to its association with respiratory illness [2]. Later studies suggested human bocavirus (HBoV) may be causative for lower respiratory tract disease in young children [3–6]. In this report, we describe the detection by quantitative real-time PCR of HBoV DNA in the nasopharyngeal aspirates of two German children hospitalized for pneumonia. Sequencing of an NP-1 gene fragment and phylogenetic analysis revealed high sequence identity for this HBoV strain compared with the prototype strain HBoV st1 [2] and other strains worldwide [2–6]. Our finding of a high viral load combined with symptoms of acute respiratory tract infection may support the assertion of others that HBoV is an important emerging pathogen [2–6]. In March 2004, a 32-month-old boy presented with a 3day history of high fever and cough. He was treated with corticosteroids and bronchodilators to control acute bronchoconstriction. No antibiotics were administered. Due to increasing tachypnea and dyspnea, the child was hospitalized. Clinical examination upon admission revealed a body temperature of 39°C, tachypnea and dyspnea, as well as subcostal retractions. Wheezing and dry bilateral fine rales were present upon lung auscultation. Transcutaneously measured oxygen saturation was decreased to 87% and the patient required oxygen supplementation (4 l/min) for 6 days and intravenous treatment with corticosteroids for persistent bronchoconstriction. Laboratory tests showed a leukocyte count of 7.7×10/l, a blood pH level of 7.4, base excess of −4.7 mmol/l, and a C-reactive protein value of 5.6 mg/l. Chest radiograph revealed beginning right paracardial pulmonary infiltration without pleural effusion, indicating pneumonia. Under antiobstructive therapy with sultanol and intravenous corticosteroids, the boy’s respiratory condition improved. On day 4 after admission, he developed rotavirus gastroenteritis, probably of nosocomial origin, which rapidly improved under symptomatic therapy. By discharge on day 9, his general condition was good, although a mild fever (38°C) was still present. In the same period, an 18-month-old boy presented with a 2-day history of increasing dyspnea, fever (39.5°C), and cough. Clinical examination revealed a weakened general condition, tachypnea, a body temperature of 38.8°C, and modest wheezing as well as bilateral basal rales upon auscultation. The patient required oxygen supplementation (2 l/min) for 4 days. Initial laboratory tests showed an elevated leukocyte count of 12.5×10/l, a blood pH level of Eur J Clin Microbiol Infect Dis (2007) 26:147–149 DOI 10.1007/s10096-006-0244-6