COVID-19: first long-term care facility outbreak in the Netherlands following cross-border introduction from Germany, March 2020.

BACKGROUND: The Dutch province of Limburg borders the German district of Heinsberg, which had a large cluster of COVID-19 cases linked to local carnival activities before any cases were reported in the Netherlands. However, Heinsberg was not included as an area reporting local or community transmission per the national case definition at the time. In early March, two residents from a long-term care facility (LTCF) in Sittard, a Dutch town located in close vicinity to the district of Heinsberg, tested positive for COVID-19. In this study we aimed to determine whether cross-border introduction of the virus took place by analysing the LTCF outbreak in Sittard, both epidemiologically and microbiologically. METHODS: Surveys and semi-structured oral interviews were conducted with all present LTCF residents by health care workers during regular points of care for information on new or unusual signs and symptoms of disease. Both throat and nasopharyngeal swabs were taken from residents suspect of COVID-19, based on regional criteria, for the detection of SARS-CoV-2 by Real-time Polymerase Chain Reaction. Additionally, whole genome sequencing was performed using a SARS-CoV-2 specific amplicon-based Nanopore sequencing approach. Moreover, twelve random residents were sampled for possible asymptomatic infections. RESULTS: Out of 99 residents, 46 got tested for COVID-19. Out of the 46 tested residents, nineteen (41%) tested positive for COVID-19, including 3 asymptomatic residents. CT-values for asymptomatic residents seemed higher compared to symptomatic residents. Eleven samples were sequenced, along with three random samples from COVID-19 patients hospitalized in the regional hospital at the time of the LTCF outbreak. All samples were linked to COVID-19 cases from the cross-border region of Heinsberg, Germany. CONCLUSIONS: Sequencing combined with epidemiological data was able to virtually prove cross-border transmission at the start of the Dutch COVID-19 epidemic. Our results highlight the need for cross-border collaboration and adjustment of national policy to emerging region-specific needs along borders in order to establish coordinated implementation of infection control measures to limit the spread of COVID-19.

Failure of vancomycin treatment for meningitis caused by vancomycin-susceptible Enterococcus faecium.

This case report describes a nosocomial vancomycin-sensitive Enterococcus faecium meningitis with poor response to vancomycin. E. faecium infections continue to represent a therapeutic challenge in Europe, even in countries where vancomycin resistance is still rare. In the case of vancomycin-sensitive E. faecium meningitis, intravenous chloramphenicol should be considered as a treatment option.

Enrichment broth improved detection of extended-spectrum-beta-lactamase-producing bacteria in throat and rectal surveillance cultures of samples from patients in intensive care units.

We evaluated the use of a trypticase soy broth (TSB) for improving detection of extended-spectrum-beta-lactamase-producing (ESBL(+)) bacteria. Preenrichment of throat and rectal swabs in TSB prior to inoculation on solid medium doubled the number of ESBL(+) bacteria detected in samples obtained from patients in our intensive care unit.

Frequent occurrence of human-associated microsporidia in fecal droppings of urban pigeons in amsterdam, the Netherlands.

Human-associated microsporidia were frequently observed in fecal samples of 331 feral pigeons in Amsterdam, The Netherlands, obtained during high- and low-breeding periods. Thirty-six of 331 samples (11%) contained the human pathogens Enterocytozoon bieneusi (n = 18), Encephalitozoon hellem (n = 11), Encephalitozoon cuniculi (n = 6), and Encephalitozoon intestinalis (n = 1); 5 samples contained other microsporidia. Pigeon feces can be an important source of human microsporidian infection.

Chlamydia caviae Causing Community-Acquired Pneumonia: An Emerging Zoonosis.

We describe a case of community-acquired pneumonia due to Chlamydia caviae in a patient with no direct animal exposure, raising questions about the zoonotic reservoirs and potential transmission routes. Genotyping of Chamydia isolates that cause pneumonia should be performed for a precise diagnosis and to initiate adequate infection control measures.

No evidence for an association of ocular adnexal lymphoma with Chlamydia psittaci in a cohort of patients from the Netherlands.

Extra-nodal marginal zone B cell lymphomas (MZBCLs) of the mucosa-associated lymphoid tissues (MALT) arise at sites of chronic antigenic stimulation due to organ-specific autoimmunity or infections, like Helicobacter pylori-associated chronic gastritis and Borrelia burgdorferi dermatitis. Recently, conflicting data have been published regarding a possible association between Chlamydia psittaci and ocular adnexal MZBCL. In the present study, we analyzed a cohort of ocular adnexal MZBLs from the Netherlands for the presence of C. psittaci DNA. We found no evidence for the presence of C. psittaci DNA in any of the tumor samples studied. Our data do not support a role for C. psittaci in the pathogenesis of ocular adnexal lymphomas in patients from the Netherlands.

An outbreak of psittacosis due to Chlamydophila psittaci genotype A in a veterinary teaching hospital.

An outbreak of psittacosis in a veterinary teaching hospital was recognized in December 2004. Outbreak management was instituted to evaluate the extent of the outbreak and to determine the avian source. Real-time PCR, serologic testing and sequencing of the ompA gene of Chlamydophila psittaci were performed. Sputum samples from patients, throat-swab samples from exposed students and staff, and faecal specimens from parrots and pigeons were tested. In this outbreak, 34 % (10/29) of the tested individuals were infected. The clinical features of the infection ranged from none to sepsis with multi-organ failure requiring intensive-care-unit admission. C. psittaci genotype A was identified as the outbreak strain. Parrots, recently exposed to a group of cockatiels coming from outside the teaching facility, which were used in a practical class, appeared to be the source of the outbreak. One of the tested pigeons harboured an unrelated C. psittaci genotype B strain. The microbiological diagnosis by real-time PCR on clinical specimens allowed for rapid outbreak management; subsequent genotyping of the isolates identified the avian source. Recommendations are made to reduce the incidence and extent of future outbreaks.

Nasal carriage of Staphylococcus aureus among surgeons and surgical residents: a nationwide prevalence study.

BACKGROUND: Staphylococcus aureus nasal carriage is an independent risk factor for developing nosocomial infections and for developing surgical site infection (SSI) in particular. The number of post-operative nosocomial S. aureus infections can be reduced by screening patients and decolonizing nasal carriers. In addition to patients, health care workers may also be S. aureus nasal carriers. The aim of this study was to explore S. aureus nasal carriage rates among surgeons. METHODS: Nasal swabs were collected from surgeons and surgical residents during a national surgical congress. The control group consisted of non-hospitalized patients. Staphylococcus aureus carriage was detected using selective chromogenic agars by use of a fully automated inoculator. Suspected colonies were identified further by positive catalase and slide coagulation reactions. RESULTS: Samples were collected from 366 surgeons and surgical residents and 950 control patients. The S. aureus nasal carriage rate among surgeons and residents was significantly greater compared with the control group (45.4% versus 30.8%, odds ratio [OR] 1.86 [1.45-2.38], p<0.001). No significant difference in carriage rate was found between surgeons and residents (46.8% versus 43.3%, p=0.769) and years of experience as a surgeon was not associated with a greater carriage rate. Male gender was an independent risk factor for carriage among physicians odds ratio ([OR] 1.90 [95% confidence interval 1.19-3.01], p=0.007). CONCLUSIONS: The nationwide rate of S. aureus nasal carriage among surgeons and surgical residents proved to be significantly greater compared with a non-hospitalized patient control group. Male gender is an independent risk factor for carriage among physicians. Future studies are needed to investigate the possible relation with nosocomial post-operative S. aureus infections.

Evaluation of the Siemens VERSANT® CT/GC DNA 1.0 assay (kPCR) for detection of Chlamydia trachomatis and Neisseria gonorrhoeae.

The Siemens VERSANT kPCR system is an automated system which combines extraction of nucleic acids from 96 samples with subsequent real-time PCR. The VERSANT CT/GC DNA 1.0 (kPCR) assay detects Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (GC) in a multiplex real-time PCR on this system. We compared this assay with the BD ProbeTe™ ET System (PT) and the Roche Cobas Amplicor (CA). Three different sets of samples were tested in the kPCR: PT pre-treated samples, prospectively collected urine samples during routine CT/GC testing and urine samples obtained in a blinded fashion by an external lab facility. Agreement of kPCR with the comparator tests was >0.99 for sample set I and complete agreement was observed for sample set II and III. The kPCR assay demonstrated to be an easy to use robust diagnostic platform. A few modifications to the manufacturer's instructions are recommended to intercept false positivity. We advise to retest samples with Cq values above 35 cycles at least one time and we suggest checking the amplification curves.

Genotyping of Chlamydophila psittaci in human samples.

Chlamydophila (formerly Chlamydia) psittaci genotypes A, B, C, and a new genotype most similar to the 6BC type strain were found in 10 humans with psittacosis by outer membrane protein A gene sequencing. Genotypes B (n = 3) and C (n = 1) are endemic in nonpsittacine European birds. These birds may represent an important part of the zoonotic reservoir.

Emergence of multidrug-resistant Gram-negative bacteria during selective decontamination of the digestive tract on an intensive care unit.

OBJECTIVES: During treatment with selective decontamination of the digestive tract (SDD), four multidrug-resistant (MDR) strains, three different Escherichia coli and one Klebsiella pneumoniae, were isolated from four patients not known as carriers of such MDR strains before their admission to the intensive care unit (ICU) in the Academic Medical Center (AMC) in Amsterdam. These isolates were extended-spectrum beta-lactamase (ESBL)-positive. We investigated whether this was due to interspecies transfer of resistance genes. METHODS: The MDR strains were typed by amplified fragment length polymorphism (AFLP) analysis. The plasmids from these strains were characterized by restriction fragment length polymorphism and the resistance genes were characterized by PCR and sequence analysis. RESULTS: The strains were genetically unrelated and contained identical plasmids with ESBL genes. CONCLUSIONS: We identified an outbreak of plasmid-mediated ESBL genes during SDD treatment in the ICU. The use of third-generation cephalosporins in SDD is associated with the emergence of ESBLs. We conclude that identification of emerging MDR Gram-negative bacteria and recognition of resistance plasmid transfer during SDD treatment are crucial for optimal application of this regimen in ICUs.

Prevalence of Chlamydophila psittaci in fecal droppings from feral pigeons in Amsterdam, The Netherlands.

In many cities, the feral rock dove is an abundant bird species that can harbor Chlamydophila psittaci. We determined the prevalence and genotype of C. psittaci in fresh fecal samples from feral pigeons in Amsterdam, The Netherlands. The prevalence was 7.9% overall (26/331; 95% confidence interval, 5 to 11). Ten genotyped PCR-positive samples were all genotype B.

A woman with a lobar infiltrate due to psittacosis detected by polymerase chain reaction.

This report presents a case of community-acquired pneumonia due to Chlamydia psittaci presenting with a lobar infiltrate and diagnosed by a newly developed ompA gene-based polymerase chain reaction (PCR). This gene encodes a specific C. psittaci major outer membrane protein. This kind of PCR could reduce antibiotic consumption and expedite outbreak management.