Tracing the adaptive evolution of SARS-CoV-2 during vaccine roll-out in Norway.

Vaccination against SARS-CoV-2 has greatly mitigated the impact of the COVID-19 pandemic. However, concerns have been raised about the degree to which vaccination might drive the emergence and selection of immune escape mutations that will hamper the efficacy of the vaccines. In this study, we investigate whether vaccination impacted the micro-scale adaptive evolution of SARS-CoV-2 in the Oslo region of Norway, during the first nine months of 2021, a period in which the population went from near-zero to almost 90 per cent vaccine coverage in the population over 50 years old.

Whole genomes from bacteria collected at diagnostic units around the world 2020.

The Two Weeks in the World research project has resulted in a dataset of 3087 clinically relevant bacterial genomes with pertaining metadata, collected from 59 diagnostic units in 35 countries around the world during 2020. A relational database is available with metadata and summary data from selected bioinformatic analysis, such as species prediction and identification of acquired resistance genes.

An emerging Panton-Valentine leukocidin-positive CC5-meticillin-resistant Staphylococcus aureus-IVc clone recovered from hospital and community settings over a 17-year period from 12 countries investigated by whole-genome sequencing.

Background: A novel Panton-Valentine leukocidin (PVL)-positive meticillin-resistant Staphylococcus aureus (MRSA) clonal complex (CC)5-MRSA-IVc ('Sri Lankan' clone) was recently described from Sri Lanka. Similar isolates caused a recent Irish hospital outbreak.

Aim: To investigate the international dissemination and diversity of PVL-positive CC5-MRSA-IVc isolates from hospital and community settings using whole-genome sequencing (WGS).

Phylodynamic signatures in the emergence of community-associated MRSA.

Community-associated, methicillin-resistant (MRSA) lineages have emerged in many geographically distinct regions around the world during the past 30 y. Here, we apply consistent phylodynamic methods across multiple community-associated MRSA lineages to describe and contrast their patterns of emergence and dissemination. We generated whole-genome sequencing data for the Australian sequence type (ST) ST93-MRSA-IV from remote communities in Far North Queensland and Papua New Guinea, and the Bengal Bay ST772-MRSA-V clone from metropolitan communities in Pakistan.

A tale of two STs: molecular and clinical epidemiology of MRSA t304 in Norway 2008-2016.

The purpose of this study was to investigate the epidemiological, molecular, and clinical characteristics of MRSA t304/ST8 and t304/ST6 in Norway from 2008 to 2016. Clinical and epidemiological data were collected for each case included in the study. Strains were characterized by PCR, spa typing, antimicrobial susceptibility testing, and whole genome sequencing.

Exploring the evolution and epidemiology of European CC1-MRSA-IV: tracking a multidrug-resistant community-associated meticillin-resistant clone.

This study investigated the evolution and epidemiology of the community-associated and multidrug-resistant clone European CC1-MRSA-IV. Whole-genome sequences were obtained for 194 European CC1-MRSA-IV isolates (189 of human and 5 of animal origin) from 12 countries, and 10 meticillin-susceptible precursors (from North-Eastern Romania; all of human origin) of the clone. Phylogenetic analysis was performed using a maximum-likelihood approach, a time-measured phylogeny was reconstructed using Bayesian analysis, and microarray genotyping was performed to identify resistance, virulence-associated and SCC (staphylococcal cassette chromosome ) genes.

Comparison of SARS-CoV-2 infections in healthcare workers with high and low exposures to Covid-19 patients in a Norwegian University Hospital.

Introduction: A year into the pandemic, the knowledge of SARS-CoV-2 infection risks among healthcare workers remains limited. In this cross-sectional study, we examined whether healthcare workers with high exposure to Covid-19 patients had a higher risk of SARS-CoV-2 infection than other healthcare workers in a Norwegian University Hospital. We also investigated the prevalence of asymptomatic healthcare workers in a ward with a SARS-CoV-2 outbreak.

Is increased Staphylococcus aureus colonization during military service caused by specific genotypes? Molecular examination of long-term carriage in a prospective cohort study.

A 22% increase in Staphylococcus aureus colonization was observed in Norwegian recruits during first year of military service. The aim was to determine whether specific genotypes caused the increase and to examine carriage status based on genotyping. Characterization of S.

Predictors of one-year all-cause mortality and infection-related mortality in patients with Staphylococcus aureus bacteraemia.

Objectives: Staphylococcus aureus bacteraemia (SAB) is a common infection associated with significant short-term mortality. Little is known about long-term prognosis. The aim of this study was to determine one-year all-cause mortality and infection-related mortality and associated predictors.

Staphylococcus aureus colonization during military service: a prospective cohort study.

Objectives: Staphylococcus aureus colonization leading to skin and soft-tissue infections (SSTI) are known challenges in crowded settings such as the military. The aim of the study was to establish and compare the prevalence of S. aureus colonization in recruits at enrolment and discharge after the first year of military service, and to investigate the prevalence of S.

No associations established between single nucleotide polymorphisms in human Toll-like receptor 2 and Toll-interacting protein and Staphylococcus aureus bloodstream infections.

Staphylococcus aureus bloodstream infections (SABSI) are associated with high morbidity and mortality. The Toll-like receptor 2 (TLR2) and Toll-interacting protein (TOLLIP) are important in recognition and regulation of human innate immunity response to S. aureus.

Emerging multidrug-resistant Bengal Bay clone ST772-MRSA-V in Norway: molecular epidemiology 2004-2014.

A multidrug-resistant, methicillin-resistant Staphylococcus aureus (MRSA) clone, PVL-positive ST772-MRSA-V, named the Bengal Bay clone, is emerging worldwide. In Norway, where MRSA prevalence is low, a sudden increase in ST772-MRSA-V initiated a nationwide molecular epidemiological study. Clinical data were obtained from the Norwegian Surveillance System for Communicable Diseases (MSIS).

Bengal Bay clone ST772-MRSA-V outbreak: conserved clone causes investigation challenges.

Background: The Bengal Bay clone, ST772-MRSA-V, associated with multi-drug resistance, Panton-Valentine leukocidin (PVL) and skin and soft tissue infections, is emerging worldwide. In Norway, a country with low prevalence of meticillin-resistant Staphylococcus aureus (MRSA), increased occurrence of ST772-MRSA-V has also caused hospital outbreaks. The conserved nature of this clone challenged the outbreak investigations.

Comparison of two single-use scrub suits in terms of effect on air-borne bacteria in the operating room.

A low level of air-borne bacteria in the operating room air can be achieved if all staff wear clothes made of low-permeability material (i.e. clean air suits).

DNA microarray analysis of Staphylococcus aureus causing bloodstream infection: bacterial genes associated with mortality?

Providing evidence for microbial genetic determinants' impact on outcome in Staphylococcus aureus bloodstream infections (SABSI) is challenging due to the complex and dynamic microbe-host interaction. Our recent population-based prospective study reported an association between the S. aureus clonal complex (CC) 30 genotype and mortality in SABSI patients.

Population-based epidemiology of Staphylococcus aureus bloodstream infection: clonal complex 30 genotype is associated with mortality.

Staphylococcus aureus bloodstream infections (SABSI) are associated with a high burden of morbidity and mortality. The impact of specific S. aureus genotypes on outcome is unclear.

Can MLVA Differentiate among Endemic-Like MRSA Isolates with Identical Spa-Type in a Low-Prevalence Region?

The prevalence of methicillin-resistant Staphylococcus aureus (MRSA) in Norway is low, but an endemic-like MRSA clone with Staphylococcal protein A (spa)-type t304 has been established especially in nursing homes in the Oslo region causing several large outbreaks. The challenge was that spa-typing and the gold standard Pulsed-Field Gel Electrophoresis (PFGE) were inadequate in discriminating isolates in outbreak investigations. Additional higher resolution genotyping methods were needed.

Comparison of three distinct clean air suits to decrease the bacterial load in the operating room: an observational study.

Background: Lowering air-borne bacteria counts in the operating room is essential in prevention of surgical site infections in orthopaedic joint replacement surgery. This is mainly achieved by decreasing bacteria counts through dilution, with appropriate ventilation and by limiting the bacteria carrying skin particles, predominantly shed by the personnel. The aim of this study was to investigate if a single use polypropylene clothing system or a reusable polyester clothing system could offer similar air quality in the operating room as a mobile laminar airflow device-assisted reusable cotton/polyester clothing system.

spa typing alone is not sufficient to demonstrate endemic establishment of meticillin-resistant Staphylococcus aureus in a low-prevalence country.

Background: The prevalence of meticillin-resistant Staphylococcus aureus (MRSA) in Norway is low but increasing. Over the last decade, numerous nursing homes have experienced MRSA outbreaks. One genetic lineage, spa type t304, has been identified at multiple nursing homes and has caused large outbreaks lasting for several years.

[Cases of MRSA in nursing homes in Oslo 2005-11].

Background: The number of infections caused by MRSA has increased substantially in Norway in the past decade. It is an objective to prevent MRSA from becoming established in nursing homes and hospitals. The purpose of the article is to describe the features of the development of MRSA cases found in nursing homes in Oslo.