Skin microbiome in atopic dermatitis

Atopic dermatitis is a common inflammatory skin disease with a complex pathogenesis that includes imbalanced immune system signalling, impaired skin barrier and enhanced Staphylococcus aureus skin colonization. The skin bacterial communities are characterized by increasing abundance of S. aureus, leading to reduced diversity compared with the bacterial communities on healthy skin, and increasing disease severity. In contrast, fungal communities are richer and more diverse on the skin of patients with atopic dermatitis, although distribution of the most common species is similar in patients and controls. Filaggrin deficiency in atopic dermatitis skin might be related to the enhanced skin colonization by S. aureus. In addition, S. aureus expressing variant virulence factors have been shown to elicit atopic dermatitis-like phenotypes in mice, indicating that specific S. aureus strains can induce flare-ups. This review aims to provide an overview of the recent literature on the skin microbiome in atopic dermatitis

Increase in invasive group A streptococcal infections and emergence of novel, rapidly expanding sub-lineage of the virulent Streptococcus pyogenes M1 clone, Denmark, 2023

Funding Information: We would like to thank Karina Kaae, Lanni Fugl Niebuhr Nielsen and Joan Nevermann Jensen for their laboratory expertise, and acknowledge the great effort by clinicians and laboratory technicians at hospitals across Denmark and at Landspítali, Reykjavik, in securing samples and data essential for WGS-based surveillance efforts, as well as the dedicated technical staff maintaining and developing the registries and epidemiological databases at the core of national surveillance in Denmark. Publisher Copyright: © 2023 European Centre for Disease Prevention and Control (ECDC). All rights reserved.A highly virulent sub-lineage of the Streptococcus pyogenes M1 clone has been rapidly expanding throughout Denmark since late 2022 and now accounts for 30% of the new invasive group A streptococcal infections. We aimed to investigate whether a shift in variant composition can account for the high incidence rates observed over winter 2022/23, or if these are better explained by the impact of COVID-19-related restrictions on population immunity and carriage of group A Streptococcus. An increase in incidence rates of invasive (iGAS) and non-invasive (nGAS) group A Streptococcus infection has been reported by several countries across Europe during the 2022/23 winter season [1-3]. Through analysis of all whole genome sequencing (WGS) data acquired for national surveillance of iGAS in Denmark since 2018, we aimed to investigate current genomic developments and the impact of emerging lineages on iGAS incidence rates in 2023. In Denmark, iGAS is not notifiable except in case of meningitis, however, test results from all 10 Departments of Clinical Microbiology (DCMs) are submitted to the Danish Microbiology Database (MiBa) [4] and can be used to monitor incidence rates. Iceland also experienced a higher iGAS incidence in early 2023, and we also present Icelandic WGS data on iGAS isolates from 2022 and 2023.Peer reviewe

Comparative subgenomic mRNA profiles of SARS-CoV-2 Alpha, Delta and Omicron BA.1, BA.2 and BA.5 sub-lineages using Danish COVID-19 genomic surveillance dataResearch in context

Summary: Background: Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has rapidly spread worldwide in the population since it was first detected in late 2019. The transcription and replication of coronaviruses, although not fully understood, is characterised by the production of genomic length RNA and shorter subgenomic RNAs to make viral proteins and ultimately progeny virions. Observed levels of subgenomic RNAs differ between sub-lineages and open reading frames but their biological significance is presently unclear. Methods: Using a large and diverse panel of virus sequencing data produced as part of the Danish COVID-19 routine surveillance together with information in electronic health registries, we assessed the association of subgenomic RNA levels with demographic and clinical variables of the infected individuals. Findings: Our findings suggest no significant statistical relationship between levels of subgenomic RNAs and host-related factors. Interpretation: Differences between lineages and subgenomic ORFs may be related to differences in target cell tropism, early virus replication/transcription kinetics or sequence features. Funding: The author(s) received no specific funding for this work

Wearing occlusive gloves increases the density of staphylococcus aureus in patients with hand eczema

Hand eczema is frequently colonized with Staphylococcus aureus. Some patients with hand eczema wear occlusive gloves regularly; however, the effect of this on the density of S. aureus is unexplored. The aim of this study is to examine the effect of occlusive gloves on the density of S. aureus sampled from the hands of patients with hand eczema. In an experimental set-up, patients with moderate-to-severe hand eczema wore an occlusive glove on one hand for 4 h with a 30-min break. Bacterial swabs were collected from the most severe eczema lesion on the hand before and immediately after glove exposure. S. aureus colony-forming units were counted and log-transformations used for comparison of before- and after-values. Among 30 patients, 19 (63%) were colonized with S. aureus. After glove occlusion S. aureus colony-forming units increased by a factor of 1.72 (p < 0.01). In conclusion, the density of sampled S. aureus on eczematous skin after prolonged wearing of occlusive gloves is greatly increased