Transmission of SARS-CoV-2 among healthcare workers and patients in a teaching hospital in the Netherlands confirmed by whole-genome sequencing.

AIM: To investigate the sources of infection among healthcare workers (HCWs) and patients in a teaching hospital in the Netherlands during the early stages of the coronavirus disease 2019 (COVID-19) pandemic using epidemiological and whole-genome sequencing data. METHODS: From 3rd April to 11th May 2020, 88 HCWs and 215 patients were diagnosed with COVID-19. Whole-genome sequences were obtained for 30 HCWs and 20 patients. RESULTS: Seven and 11 sequence types were identified in HCWs and patients, respectively. Cluster A was the most common sequence type, detected in 23 (77%) HCWs; of these, 14 (61%) had direct patient contact and nine (39%) had indirect patient contact. In addition, seven patients who were not hospitalized in the COVID-19 cohort isolation ward who became positive during their admission were infected with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) cluster A. Following universal masking of all HCWs and emphasis on physical distancing during meals and breaks, no further evidence was found for patient-to-HCW or HCW-to-HCW transmission or vice versa. CONCLUSION: The finding that patients and HCWs were infected with SARS-CoV-2 cluster A suggests both HCW-to-HCW and HCW-to-patient transmission.

Characterization of fluoroquinolone and cephalosporin resistance mechanisms in Enterobacteriaceae isolated in a Dutch teaching hospital reveals the presence of an Escherichia coli ST131 clone with a specific mutation in parE.

OBJECTIVES: To characterize the mechanisms of fluoroquinolone and cephalosporin resistance in Enterobacteriaceae from a Dutch teaching hospital in 2008. METHODS: We sequenced gyrA, gyrB, parC and parE. The presence of plasmid-encoded genes qnrA, qnrB, qnrS, aac(6')-Ib, qepA, bla(TEM), bla(SHV,) bla(OXA), bla(CTX-M) and bla(AmpC) was studied by PCR. Escherichia coli isolates were further characterized by AFLP and multilocus sequence typing (MLST). RESULTS: In total, 49 E. coli, 16 Klebsiella pneumoniae and 3 Enterobacter cloacae isolates were investigated. Mutations in gyrA were found in all E. coli isolates. Forty-five (92%) E. coli isolates carried at least one point mutation in parC. Most E. coli isolates (59%) also carried mutations in parE, of which I529L was the most prevalent. I529L was unequivocally associated with E. coli sequence type (ST) 131. This single-nucleotide polymorphism (SNP) was later also found in eight out of nine ST131 strains from another collection. Twenty-nine E. coli isolates carried extended-spectrum ß-lactamase (ESBL) genes, predominantly bla(CTX-M-15). In E. coli, aac(6')-Ib-cr was the predominant plasmid-mediated resistance mechanism, whereas in K. pneumoniae qnr genes were found mostly. In K. pneumoniae isolates, qnr and aac(6')-Ib-cr co-occurred with ESBL genes (n = 13; bla(CTX-M) and bla(SHV)) and/or bla(AmpC) (n = 3; bla(DHA-1)). CONCLUSIONS: E. coli ST131 was the predominant clone, which accumulated a high number of chromosomal mutations. The I529L SNP in parE was a signature of most, but not all, ST131 strains. In contrast to E. coli, fluoroquinolone resistance mechanisms were predominantly plasmid-encoded in K. pneumoniae.

Characteristics and incidence of Clostridium difficile-associated disease in The Netherlands, 2005.

During a 2-month period in 2005, 13 laboratories participated in a surveillance study of Clostridium difficile-associated disease (CDAD) in 17 hospitals in The Netherlands. The median incidence rate of CDAD was 16/10 000 patient admissions (2.2/10 000 patient-days) and varied from 1 to 46/10 000 patient admissions according to hospital. In total, 81 patients with CDAD were reported; 49 (61%) patients had nosocomial CDAD, and 29 (36%) patients were admitted to hospital when already suffering from diarrhoea. Two (2%) deaths were attributable to CDAD; both of these patients were admitted with severe community-onset CDAD and were aged >80 years. Among 64 toxinogenic isolates, ten (16%) belonged to PCR ribotype 027 and ten (16%) to PCR ribotype 014. Type 027 was identified in ten patients from one hospital during an unrecognised outbreak. Toxinotyping of the 64 isolates revealed the presence of six different toxinogenic types, with 41 (64%) isolates of toxinotype 0, ten (16%) isolates of toxinotype III, and nine (14%) isolates of toxinotype V. Of the 64 toxinogenic isolates, seven (11%) had a 39-bp deletion in the tcdC gene, 11 (17%) had an 18-bp deletion, and one (1%) had a deletion of c. 44 bp. Genes for binary toxin were present in 21 (33%) of the 64 toxinogenic isolates, mainly associated with toxinotypes III and V. It was concluded that the median CDAD incidence rate of 16/10 000 patient admissions in The Netherlands is considerably lower than that in Canada and the USA, and that the emerging type 027 can spread unnoticed. The high proportion (36%) of CDAD cases with a community onset has important implications for future studies of the epidemiology of CDAD.

Expression of beta-defensin-1 in chimpanzee (Pan troglodytes) airways.

In human airways, beta-defensins function in the elimination of various pathogens. They have been identified in a wide range of species. Here we report the identification and expression of chimpanzee beta-defensin-1 (cBD1), which is a homolog of human beta-defensin-1, in chimpanzee airways and skin. The cBD1 cDNA sequence differs by only one synonymous nucleotide substitution compared to the human cDNA sequence. In situ hybridization revealed that in lung tissue beside alveolar macrophages also airway epithelial cells, endothelial cells and type II pneumocytes express cBD1 mRNA. In skin, cBD1 mRNA was expressed in keratinocytes and endothelial cells. Together, these results show similarity in structure and expression pattern and perhaps in function.