Specific memory B cell response in humans upon infection with highly pathogenic H7N7 avian influenza virus.

H7 avian influenza viruses represent a major public health concern, and worldwide outbreaks raise the risk of a potential pandemic. Understanding the memory B cell response to avian (H7) influenza virus infection in humans could provide insights in the potential key to human infection risks. We investigated an epizootic of the highly pathogenic A(H7N7) in the Netherlands, which in 2003 led to infection of 89 persons and one fatal case.

Seasonality in carriage of extended-spectrum -lactamase-producing and in the general population: a pooled analysis of nationwide cross-sectional studies.

Infections due to extended-spectrum β-lactamase-producing Enterobacteriaceae (ESBL-E) are often preceded by asymptomatic carriage. Higher incidences in enteric infectious diseases during summer have been reported. Here, we assessed whether the presence of seasonality in intestinal ESBL-Escherichia coli/Klebsiella pneumoniae (ESBL-E/K) carriage in the general Dutch population exists.

Differences in isolation rate and antimicrobial susceptibility of bacteria isolated from foals with sepsis at admission and after ≥48 hours of hospitalization.

Background: Antimicrobial treatment protocols for foals with sepsis that do not improve clinically often are adjusted based on bacteriological and antimicrobial susceptibility testing results from samples collected at hospital admission.

Objectives: To evaluate whether hospitalization for ≥48 hours affects bacteriological and antimicrobial susceptibility testing results.

Animals: Two-hundred sixty-seven foals <30 days of age admitted to a neonatal intensive care unit and diagnosed with sepsis.

Molecular characteristics of carbapenemase-producing Enterobacterales in the Netherlands; results of the 2014-2018 national laboratory surveillance.

Objectives: Carbapenem resistance mediated by mobile genetic elements has emerged worldwide and has become a major public health threat. To gain insight into the molecular epidemiology of carbapenem resistance in The Netherlands, Dutch medical microbiology laboratories are requested to submit suspected carbapenemase-producing Enterobacterales (CPE) to the National Institute for Public Health and the Environment as part of a national surveillance system.

Methods: Meropenem MICs and species identification were confirmed by E-test and MALDI-TOF and carbapenemase production was assessed by the Carbapenem Inactivation Method.

Transmission of ESBL-producing Escherichia coli between broilers and humans on broiler farms.

Background: ESBL and AmpC β-lactamases are an increasing concern for public health. Studies suggest that ESBL/pAmpC-producing Escherichia coli and their plasmids carrying antibiotic resistance genes can spread from broilers to humans working or living on broiler farms. These studies used traditional typing methods, which may not have provided sufficient resolution to reliably assess the relatedness of these isolates.

Do vegetarians less frequently carry ESBL/pAmpC-producing Escherichia coli/Klebsiella pneumoniae compared with non-vegetarians?

Background: ESBL and plasmid-mediated AmpC (pAmpC)-producing Enterobacteriaceae are frequently found on meat products in Dutch retail, especially on poultry.

Objectives: We investigated whether vegetarians are at lower risk of carrying ESBL/pAmpC-producing Escherichia coli/Klebsiella pneumoniae (ESBL-E/K) compared with persons who consume meat.

Methods: Vegetarians, pescatarians (vegetarians who eat fish) and non-vegetarians (persons who eat meat at least three times per week) were asked to send in a faecal sample and a questionnaire.

Host factors associated with Giardia duodenalis infection in dogs across multiple diagnostic tests.

Background: The aim of this study was to assess potential associations between Giardia duodenalis infection in dogs, as determined by three diagnostic tests, and dog's group of origin, fecal consistency, age, sex, neuter status, and co-infections with other gastrointestinal parasites.

Methods: Fecal samples from 1291 dogs from four groups (household, shelter, hunting and clinical dogs) were tested with qPCR, rapid enzyme immunochromatographic assay (IDEXX SNAP Giardia), and direct immunofluorescence (DFA, Merifluor) for presence of G. duodenalis.

Immunoglobulin A deficiency in children, an undervalued clinical issue.

Immunoglobulin A (IgA) is the principal antibody in secretions that bathe the gastrointestinal and respiratory mucosal surfaces and acts as an important first line of defense against invasion of pathogenic micro-organisms. The reported prevalence rate of complete IgA deficiency in healthy children ranges from 1:170 to 1:400, and as a solitary condition, it is often considered of limited clinical importance. However, patients with IgA deficiency can develop recurrent respiratory and gastrointestinal infections, as well as allergic and autoimmune diseases.

Getting under the birds' skin: tissue tropism of Borrelia burgdorferi s.l. in naturally and experimentally infected avian hosts.

Wild birds are frequently exposed to the zoonotic tick-borne bacteria Borrelia burgdorferi sensu lato (s.l.), and some bird species act as reservoirs for some Borrelia genospecies.

Attributable sources of community-acquired carriage of Escherichia coli containing β-lactam antibiotic resistance genes: a population-based modelling study.

Background: Extended-spectrum β-lactamase-producing Escherichia coli (ESBL-EC), plasmid-mediated AmpC-producing E coli (pAmpC-EC), and other bacteria are resistant to important β-lactam antibiotics. ESBL-EC and pAmpC-EC are increasingly reported in animals, food, the environment, and community-acquired and health-care-associated human infections. These infections are usually preceded by asymptomatic carriage, for which attributions to animal, food, environmental, and human sources remain unquantified.

Anaplasma phagocytophilum evolves in geographical and biotic niches of vertebrates and ticks.

Background: Anaplasma phagocytophilum is currently regarded as a single species. However, molecular studies indicate that it can be subdivided into ecotypes, each with distinct but overlapping transmission cycle. Here, we evaluate the interactions between and within clusters of haplotypes of the bacterium isolated from vertebrates and ticks, using phylogenetic and network-based methods.

The effect of body mass index on the risk of surgical site infection.

Objective: Obesity is considered a risk factor for surgical site infection (SSI). We quantified impact of body mass index (BMI) on the risk of SSI for a variety of surgical procedures.

Methods: We included 2012-2017 data from the Dutch national surveillance network PREZIES on a selection of frequently performed surgical procedures across different specialties.

Home style frying of steak and meat products: Survival of Escherichia coli related to dynamic temperature profiles.

Microbial survival of heating and cross-contamination are the two transmission routes during food preparation in the consumers' kitchen that are relevant for QMRA (Quantitative Microbial Risk Assessment). The aim of the present study was to extend the limited amount of data on microbial survival during real-life preparation of meat and meat products and to obtain accessory temperature data that allow for a more general (product unspecific) approach. Therefore survival data were combined with extensive measurements of time- and location dependent temperature using an infrared camera for the surface and buttons for the inside of the product, supplemented with interpolation modelling.

Comparative genomics reveals a lack of evidence for pigeons as a main source of stx-carrying Escherichia coli causing disease in humans and the common existence of hybrid Shiga toxin-producing and enteropathogenic E. coli pathotypes.

Background: Wild birds, in particular pigeons are considered a natural reservoir for stx-carrying E. coli. An extensive comparison of isolates from pigeons and humans from the same region is lacking, which hampers justifiable conclusions on the epidemiology of these pathogens.

Genospecies of Borrelia burgdorferi sensu lato detected in 16 mammal species and questing ticks from northern Europe.

Lyme borreliosis is the most common vector-borne zoonosis in the northern hemisphere, and the pathogens causing Lyme borreliosis have distinct, incompletely described transmission cycles involving multiple host groups. The mammal community in Fennoscandia differs from continental Europe, and we have limited data on potential competent and incompetent hosts of the different genospecies of Borrelia burgdorferi sensu lato (sl) at the northern distribution ranges where Lyme borreliosis is emerging. We used qPCR to determine presence of B.

Infection prevalence and ecotypes of Anaplasma phagocytophilum in moose Alces alces, red deer Cervus elaphus, roe deer Capreolus capreolus and Ixodes ricinus ticks from Norway.

Background: The geographical expansion of the tick Ixodes ricinus in northern Europe is a serious concern for animal and human health. The pathogen Anaplasma phagocytophilum is transmitted by ticks and causes emergences of tick-borne fever (anaplasmosis) in livestock. The transmission dynamics of the different ecotypes of A.

Echovirus type 6 transmission clusters and the role of environmental surveillance in early warning, the Netherlands, 2007 to 2016.

BackgroundIn the Netherlands, echovirus type 6 (E6) is identified through clinical and environmental enterovirus surveillance (CEVS and EEVS). AimWe aimed to identify E6 transmission clusters and to assess the role of EEVS in surveillance and early warning of E6. MethodsWe included all E6 strains from CEVS and EEVS from 2007 through 2016.

A systematic knowledge synthesis on the spatial dimensions of Q fever epidemics.

From 2007 through 2010, the Netherlands experienced the largest Q fever epidemic ever reported. This study integrates the outcomes of a multidisciplinary research programme on spatial airborne transmission of Coxiella burnetii and reflects these outcomes in relation to other scientific Q fever studies worldwide. We have identified lessons learned and remaining knowledge gaps.

Inhibiting ex-vivo Th17 responses in Ankylosing Spondylitis by targeting Janus kinases.

Treatment options for Ankylosing Spondylitis (AS) are still limited. The T helper cell 17 (Th17) pathway has emerged as a major driver of disease pathogenesis and a good treatment target. Janus kinases (JAK) are key transducers of cytokine signals in Th17 cells and therefore promising targets for the treatment of AS.

Longitudinal study of ESBL Escherichia coli carriage on an organic broiler farm.

Objectives: To determine the molecular characteristics of ESBL-producing Escherichia coli (ESBL-E) collected during a longitudinal study on an organic broiler farm in order to investigate clonal expansion and horizontal gene transfer.

Methods: Isolates were obtained from a longitudinal study performed previously on an organic broiler fattening farm. Samples from individually followed-up broilers, the broiler house, the transport van and persons that took the samples, taken at several timepoints (days 1, 3, 4, 7, 10, 42 and 70) within a production round and during the consecutive one (days 1, 2, 3 and 70), had been investigated for the occurrence of ESBL-E.

Effects of pre-existing orthopoxvirus-specific immunity on the performance of Modified Vaccinia virus Ankara-based influenza vaccines.

The replication-deficient orthopoxvirus modified vaccinia virus Ankara (MVA) is a promising vaccine vector against various pathogens and has an excellent safety record. However, pre-existing vector-specific immunity is frequently suggested to be a drawback of MVA-based vaccines. To address this issue, mice were vaccinated with MVA-based influenza vaccines in the presence or absence of orthopoxvirus-specific immunity.

Opsonic Phagocytosis in Chronic Obstructive Pulmonary Disease Is Enhanced by Nrf2 Agonists.

Rationale: Previous studies have identified defects in bacterial phagocytosis by alveolar macrophages (AMs) in patients with chronic obstructive pulmonary disease (COPD), but the mechanisms and clinical consequences remain incompletely defined.

Objectives: To examine the effect of COPD on AM phagocytic responses and identify the mechanisms, clinical consequences, and potential for therapeutic manipulation of these defects.

Methods: We isolated AMs and monocyte-derived macrophages (MDMs) from a cohort of patients with COPD and control subjects within the Medical Research Council COPDMAP consortium and measured phagocytosis of bacteria in relation to opsonic conditions and clinical features.

Age-Dependent Pre-Vaccination Immunity Affects the Immunogenicity of Varicella Zoster Vaccination in Middle-aged Adults.

Background: Prevention of infectious diseases is of high priority in the rapidly aging population. Unfortunately, vaccine responses in the elderly are frequently diminished. Timely vaccination of middle-aged adults might improve the immune responses to vaccines, although knowledge on pathogen-specific immune responses and factors affecting these responses, in middle-aged adults is currently limited.

An Explorative Biomarker Study for Vaccine Responsiveness after a Primary Meningococcal Vaccination in Middle-Aged Adults.

Introduction: Prevention of infectious diseases in the elderly is essential to establish healthy aging. Yet, immunological aging impairs successful vaccination of the elderly. Predictive biomarkers for vaccine responsiveness in middle-aged adults may help to identify responders and non-responders before reaching old age.