To the Editor: Legionnaires' disease is an often severe form of pneumonia that is typically acquired by susceptible persons (e.g., elderly persons and smokers) through inhalation of aerosols that contain legionella species. 1-4 A cluster of cases of this disease occurred in Vila Franca de Xira, Portugal, in 2014. 5 One of the first cases of disease in this cluster occurred in a 48-year-old man (Patient 1), a smoker, who had been employed since October 6, 2014, as a maintenance worker at an industrial cooling tower complex in Vila Franca de Xira that was subsequently found to be contaminated with Legionella pneumophila. 5 He returned to the home that he shared with is mother in Porto (approximately 300 km from Vila Franca de Xira) on October 11 and again on the evening of October 19 (Fig. 1). His symptoms began on October 14, and on October 19, he had severe respiratory symptoms, including an intense cough. During that night, his mother (Patient 2) took care of him until he was admitted to the hospital (Centro Hospitalar do Porto) approximately 8 hours later. On October 22, he was transferred to another hospital to receive extracorporeal membrane oxygenation. On October 27, Patient 2, who was a previously healthy 74-year-old woman, began to report fever, cough, and loss of appetite. She was admitted to the same hospital on November 3 with septic shock due to pneumonia, and she died on December 1. Patient 1 died on January 7, 2015. Urine specimens obtained from both patients showed positive results on testing for legionella
A first strong evidence of person-to-person transmission of Legionnaires’ Disease (LD) was recently reported. Here, we characterize the genetic backbone of this case-related Legionella pneumophila strain (“PtVFX/2014”), which also caused a large outbreak of LD. PtVFX/2014 is phylogenetically divergent from the most worldwide studied outbreak-associated L. pneumophila subspecies pneumophila serogroup 1 strains. In fact, this strain is also from serogroup 1, but belongs to the L. pneumophila subspecies fraseri. Its genomic mosaic backbone reveals eight horizontally transferred regions encompassing genes, for instance, involved in lipopolysaccharide biosynthesis or encoding virulence-associated Dot/Icm type IVB secretion system (T4BSS) substrates. PtVFX/2014 also inherited a rare ~65 kb pathogenicity island carrying virulence factors and detoxifying enzymes believed to contribute to the emergence of best-fitted strains in water reservoirs and in human macrophages, as well as a inter-species transferred (from L. oakridgensis) ~37.5 kb genomic island (harboring a lvh/lvr T4ASS cluster) that had never been found intact within L. pneumophila species. PtVFX/2014 encodes another lvh/lvr cluster near to CRISPR-associated genes, which may boost L. pneumophila transition from an environmental bacterium to a human pathogen. Overall, this unique genomic make-up may impact PtVFX/2014 ability to adapt to diverse environments, and, ultimately, to be transmitted and cause human disease.
gMeat and meat products are important sources of human intestinal infections. We report the isolation of Helicobacter pullorum strains from chicken meat. Bacteria were isolated from 4 of the 17 analyzed fresh chicken meat samples, using a membrane filter method. MIC determination revealed that the four strains showed acquired resistance to ciprofloxacin; one was also resistant to erythromycin, and another one was resistant to tetracycline. Whole-genome sequencing of the four strains and comparative genomics revealed important genetic traits within the H. pullorum species, such as 18 highly polymorphic genes (including a putative new cytotoxin gene), plasmids, prophages, and a complete type VI secretion system (T6SS). The T6SS was found in three out of the four isolates, suggesting that it may play a role in H. pullorum pathogenicity and diversity. This study suggests that the emerging pathogen H. pullorum can be transmitted to humans by chicken meat consumption/contact and constitutes an important contribution toward a better knowledge of the genetic diversity within the H. pullorum species. In addition, some genetic traits found in the four strains provide relevant clues to how this species may promote adaptation and virulence. Infectious diarrhea is a major cause of morbidity and mortality throughout the world, particularly in children (1). Besides the most commonly associated pathogens, such as Salmonella enterica, Campylobacter spp., and Shiga toxin-producing Escherichia coli, infectious intestinal pathogens also include Helicobacter species. Among these, Helicobacter pullorum has been detected in poultry as well as in human samples (2, 3).H. pullorum is a Gram-negative, gently curved rod, with an unsheathed monopolar flagellum (4). This enterohepatic Helicobacter species was initially isolated from the liver, duodenum, and cecum of asymptomatic poultry, but it has also been associated with enteritis and vibrionic hepatitis in broiler chickens and laying hens (4). In poultry, H. pullorum was found to colonize the cecum at high concentrations, as well as to be present on poultry carcasses, possibly due to contamination during slaughtering. Therefore, the potential role of this bacterium as an emerging foodborne human pathogen needs to be considered (3, 5-7). In humans, H. pullorum is considered an emergent agent implicated in several digestive pathologies, such as gastroenteritis (2) and chronic inflammatory conditions of the intestine (8, 9) and liver (for a review, see reference 10 and references cited therein). However, the lack of available detection tools and the difficulties in cultivating this fastidious organism result in an underdetection of the pathogen and underdiagnosis of the associated infection. Despite its zoonotic potential, there is no proof to date that one can acquire H. pullorum infection by the handling and consumption of raw or undercooked broiler chicken meat.In the present work, we report the isolation of H. pullorum from chicken meat and present antimicrobial susceptibility data and ...
Helicobacter pylori genetic diversity is known to be influenced by mobile genomic elements. Here we focused on prophages, the least characterized mobile elements of H. pylori. We present the full genomic sequences, insertion sites and phylogenetic analysis of 28 prophages found in H. pylori isolates from patients of distinct disease types, ranging from gastritis to gastric cancer, and geographic origins, covering most continents. The genome sizes of these prophages range from 22.6–33.0 Kbp, consisting of 27–39 open reading frames. A 36.6% GC was found in prophages in contrast to 39% in H. pylori genome. Remarkably a conserved integration site was found in over 50% of the cases. Nearly 40% of the prophages harbored insertion sequences (IS) previously described in H. pylori. Tandem repeats were frequently found in the intergenic region between the prophage at the 3′ end and the bacterial gene. Furthermore, prophage genomes present a robust phylogeographic pattern, revealing four distinct clusters: one African, one Asian and two European prophage populations. Evidence of recombination was detected within the genome of some prophages, resulting in genome mosaics composed by different populations, which may yield additional H. pylori phenotypes.
In Portugal, the epidemiological stage for the spread of carbapenemase-producing Enterobacteriaceae (CPE) increased from sporadic isolates or single hospital clones (2010–2013), to hospital outbreaks, later. Here we report data from a 6-month study performed under the European Survey on Carbapenemase-Producing Enterobacteriaceae (EuSCAPE). During the study period, 67 isolates (61 Klebsiella pneumoniae and 6 Escherichia coli) non-susceptible to carbapenems were identified in participant hospital laboratories. We detected 37 blaKPC–type (including one new variant: blaKPC–21), 1 blaGES–5, and 1 blaGES–6 plus blaKPC–3, alone or in combination with other bla genes. Bioinformatics analysis of the KPC-21-producing E. coli identified the new variant blaKPC–21 in a 12,748 bp length plasmid. The blaKPC–21 gene was harbored on a non-Tn4401 element, presenting upstream a partial ISKpn6 (ΔISKpn6/ΔtraN) with the related left IR (IRL) and downstream a truncated Tn3 transposon. PFGE and MLST analysis showed an important diversity, as isolates belonged to distinct PFGE and STs profiles. In this study, we highlighted the presence of the high-risk clone E. coli sequence-type (ST) 131 clade C/H30. This worldwide disseminated E. coli lineage was already detected in Portugal among other antibiotic resistance reservoirs. This study highlights the intra- and inter-hospital spread and possible intercontinental circulation of CPE isolates.
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