Candida parapsilosis infection in very low birthweight infants

In a UK national surveillance study, we found that Candida parapsilosis accounted for one quarter of all cases of invasive fungal infection in very low birthweight infants. C parapsilosis was associated with fewer deep-seated infections than C albicans, but mortality was similar. Ongoing surveillance is needed to monitor the epidemiology of invasive fungal infection in very low birthweight infants.This study was partly supported by an educational grant provided by Pfizer UK

Enhanced nasopharyngeal infection and shedding associated with an epidemic lineage of emm3 group A Streptococcus

Background: A group A Streptococcus (GAS) lineage of genotype emm3, sequence type 15 (ST15) was associated with a six month upsurge in invasive GAS disease in the UK. The epidemic lineage (Lineage C) had lost two typical emm3 prophages, Φ315.1 and Φ315.2 associated with the superantigen ssa, but gained a different prophage (ΦUK-M3.1) associated with a different superantigen, speC and a DNAse spd1. Methods and Results: The presence of speC and spd1 in Lineage C ST15 strains enhanced both in vitro mitogenic and DNAse activities over non-Lineage C ST15 strains. Invasive disease models in Galleria mellonella and SPEC-sensitive transgenic mice, revealed no difference in overall invasiveness of Lineage C ST15 strains compared to non-Lineage C ST15 strains, consistent with clinical and epidemiological analysis. Lineage C strains did however markedly prolong murine nasal infection with enhanced nasal and airborne shedding compared to non-Lineage C strains. Deletion of speC or spd1 in two Lineage C strains identified a possible role for spd1 in airborne shedding from the murine nasopharynx. Conclusions: Nasopharyngeal infection and shedding of Lineage C strains was enhanced compared to nonLineage C strains and this was, in part, mediated by the gain of the DNase spd1 through prophage acquisition

Future priorities of acute hospitals for surgical site infection surveillance in England

BACKGROUND: Since the launch of the national surgical site infection (SSI) surveillance service in 1997, successive expansions of the programme provided hospitals with increasing flexibility in procedures to target through surveillance. Ensuring the programme continues to meet hospitals' needs remains essential. AIM: As a means to inform the future direction of the service, a survey of all acute NHS Trusts was undertaken to assess and understand priorities for surveillance. METHODS: A web-based survey was circulated to acute NHS Trust infection control teams in England asking them to identify and rank i) reasons for undertaking current SSI surveillance ii) priority surgical categories for future SSI surveillance and iii) reasons for prioritising these categories. FINDINGS: Of the 161 Trusts surveyed, 84 (52%) responded. Assessment of quality of care was identified as the most common driver for SSI surveillance activity. Considerable heterogeneity in priority areas was observed, with 24 different surgical categories selected as top priority. Of the procedures undertaken by 15 or more Trusts, Caesarean section (2.7), hip replacement (2.8) and coronary artery bypass graft (2.9) were highest ranked. All 17 categories in the current surveillance programme were selected as a top priority by one or more Trusts. CONCLUSION: Whilst the majority of hospitals' priorities for SSI surveillance are included in the current programme, the top ranked priority, Caesarean section, is not included. Given the diversity of priority areas, maintaining a comprehensive spectrum of categories in the national programme is essential to assist hospitals in addressing local prioritie

Emergence of a novel lineage containing a prophage in emm/M3 group A Streptococcus associated with upsurge in invasive disease in the UK

A sudden increase in invasive Group A Streptococcus (iGAS) infections associated with emm/M3 isolates during the winter of 2008/09 prompted the initiation of enhanced surveillance in England. In order to characterise the population of emm/M3 GAS within the UK and determine bacterial factors that might be responsible for this upsurge, 442 emm/M3 isolates from cases of invasive and non-invasive infections during the period 2001–2013 were subjected to whole genome sequencing. MLST analysis differentiated emm/M3 isolates into three sequence types (STs): ST15, ST315 and ST406. Analysis of the whole genome SNP-based phylogeny showed that the majority of isolates from the 2008–2009 upsurge period belonged to a distinct lineage characterized by the presence of a prophage carrying the speC exotoxin and spd1 DNAase genes but loss of two other prophages considered typical of the emm/M3 lineage. This lineage was significantly associated with the upsurge in iGAS cases and we postulate that the upsurge could be attributed in part to expansion of this novel prophage-containing lineage within the population. The study underlines the importance of prompt genomic analysis of changes in the GAS population, providing an advanced public health warning system for newly emergent, pathogenic strains

Turner et al. Reply to "Emergence of the Same Successful Clade among Distinct Populations of emm89 Streptococcus pyogenes in Multiple Geographic Regions"

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Emergence of a New Highly Successful Acapsular Group A Streptococcus Clade of Genotype emm89 in the United Kingdom

UNLABELLED: Group A Streptococcus (GAS) genotype emm89 is increasingly recognized as a leading cause of disease worldwide, yet factors that underlie the success of this emm type are unknown. Surveillance identified a sustained nationwide increase in emm89 invasive GAS disease in the United Kingdom, prompting longitudinal investigation of this genotype. Whole-genome sequencing revealed a recent dramatic shift in the emm89 population with the emergence of a new clade that increased to dominance over previous emm89 variants. Temporal analysis indicated that the clade arose in the early 1990s but abruptly increased in prevalence in 2008, coinciding with an increased incidence of emm89 infections. Although standard variable typing regions (emm subtype, tee type, sof type, and multilocus sequence typing [MLST]) remained unchanged, uniquely the emergent clade had undergone six distinct regions of homologous recombination across the genome compared to the rest of the sequenced emm89 population. Two of these regions affected known virulence factors, the hyaluronic acid capsule and the toxins NADase and streptolysin O. Unexpectedly, and in contrast to the rest of the sequenced emm89 population, the emergent clade-associated strains were genetically acapsular, rendering them unable to produce the hyaluronic acid capsule. The emergent clade-associated strains had also acquired an NADase/streptolysin O locus nearly identical to that found in emm12 and modern emm1 strains but different from the rest of the sequenced emm89 population. The emergent clade-associated strains had enhanced expression of NADase and streptolysin O. The genome remodeling in the new clade variant and the resultant altered phenotype appear to have conferred a selective advantage over other emm89 variants and may explain the changes observed in emm89 GAS epidemiology. IMPORTANCE: Sudden upsurges or epidemic waves are common features of group A streptococcal disease. Although the mechanisms behind such changes are largely unknown, they are often associated with an expansion of a single genotype within the population. Using whole-genome sequencing, we investigated a nationwide increase in invasive disease caused by the genotype emm89 in the United Kingdom. We identified a new clade variant that had recently emerged in the emm89 population after having undergone several core genomic recombination-related changes, two of which affected known virulence factors. An unusual finding of the new variant was the loss of the hyaluronic acid capsule, previously thought to be essential for causing invasive disease. A further genomic adaptation in the NADase/streptolysin O locus resulted in enhanced production of these toxins. Recombination-related genome remodeling is clearly an important mechanism in group A Streptococcus that can give rise to more successful and potentially more pathogenic variants

Time to negative throat culture following initiation of antibiotics for pharyngeal group A Streptococcus: a systematic review and meta-analysis up to October 2021 to inform public health control measures

Background: Public health guidance recommending isolation of individuals with group A streptococcal (GAS) infection or carriage for 12–24 h from antibiotic initiation to prevent onward transmission requires a strong evidence base. Aim: To estimate the pooled proportion of individuals who remain GAS culture-positive at set intervals after initiation of antibiotics through a systematic literature review (PROSPERO CRD42021290364) and meta-analysis. Methods: We searched Ovid MEDLINE (1946–), EMBASE (1974–) and Cochrane library. We included interventional or observational studies with ≥ 10 participants reporting rates of GAS throat culture positivity during antibiotic treatment for culture-confirmed GAS pharyngitis, scarlet fever and asymptomatic pharyngeal GAS carriage. We did not apply age, language or geographical restrictions. Results: Of 5,058 unique records, 43 were included (37 randomised controlled studies, three non-randomised controlled trials and three before-and-after studies). The proportion of individuals remaining culture-positive on day 1, day 2 and days 3–9 were 6.9% (95% CI: 2.7–16.8%), 5.4% (95% CI: 2.1–13.3%) and 2.6% (95% CI: 1.6–4.2%). For penicillins and cephalosporins, day 1 positivity was 6.5% (95% CI: 2.5–16.1%) and 1.6% (95% CI: 0.04–42.9%), respectively. Overall, for 9.1% (95% CI: 7.3–11.3), throat swabs collected after completion of therapy were GAS culture-positive. Only six studies had low risk of bias. Conclusions: Our review provides evidence that antibiotics for pharyngeal GAS achieve a high rate of culture conversion within 24 h but highlights the need for further research given methodological limitations of published studies and imprecision of pooled estimates. Further evidence is needed for non-beta-lactam antibiotics and asymptomatic individuals

Household transmission of invasive group A Streptococcus infections in England: a population-based study, 2009, 2011 to 13

Invasive group A s treptococcal infection has a 15% case fatality rate and a risk of secondary transmission. This retrospective study us ed two national data sources from England ; enhanced surveillance ( 2009) and a case management system ( 2011 - 13) to identify clusters of sever e group A streptococcal disease . 2 4 household pairs were identified. The median onset interval between cases was 2 days (range 0 - 28) with simultaneous onset in 8 pairs . The attack rate during the 30 days after first exposure to a primary case was 4 52 0 per 100000 person - years at risk (95% CI 2 900 - 673 0 ) a 19 40 ( 12 40 - 28 80 ) fold elevation over the background incidence . The theoretical number needed to treat ( NNT ) to prevent one secondary case using antibiotic prophylaxis was 2 71 ( 194 - 454 ) overall, 50 for mother - neonate pairs ( 2 7 - 3 93 ) and 8 2 for couples aged 75 years and over ( 46 - 417 ). Whilst a dramatic increased risk of infection was noted in all household contacts, increased ris k was greatest for mother - neonate pairs and couples aged 75 and over , suggesting targeted prophylaxis c ould be considered. Offering prophylaxis is challenging due to the short time interval between cases emphasising the importance of immediate notification and assessment of contacts

Emerging invasive group A Streptococcus M1UK lineage detected by allele-specific PCR, England, 2020

Increasing reports of invasive Streptococcus pyogenes infections mandate surveillance for toxigenic lineage M1UK. An allele-specific PCR was developed to distinguish M1UK from other emm1 strains. The M1UK lineage represented 91% of invasive emm1 isolates in England in 2020. Allele-specific PCR will permit surveillance for M1UK without need for genome sequencing