scholarly journals Legionellosis Caused by Non-Legionella pneumophila Species, with a Focus on Legionella longbeachae

2021 ◽  
Vol 9 (2) ◽  
pp. 291
Author(s):  
Stephen T. Chambers ◽  
Sandy Slow ◽  
Amy Scott-Thomas ◽  
David R. Murdoch
Keyword(s):  
New Zealand ◽  
Legionella Pneumophila ◽  
Community Acquired Pneumonia ◽  
High Rate ◽  
Surveillance Systems ◽  
Secretion Systems ◽  
Public Health Response ◽  
Cell Functions ◽  
Worldwide Distribution ◽  
Legionella Species

Although known as causes of community-acquired pneumonia and Pontiac fever, the global burden of infection caused by Legionella species other than Legionella pneumophila is under-recognised. Non-L. pneumophila legionellae have a worldwide distribution, although common testing strategies for legionellosis favour detection of L. pneumophila over other Legionella species, leading to an inherent diagnostic bias and under-detection of cases. When systematically tested for in Australia and New Zealand, L. longbeachae was shown to be a leading cause of community-acquired pneumonia. Exposure to potting soils and compost is a particular risk for infection from L. longbeachae, and L. longbeachae may be better adapted to soil and composting plant material than other Legionella species. It is possible that the high rate of L. longbeachae reported in Australia and New Zealand is related to the composition of commercial potting soils which, unlike European products, contain pine bark and sawdust. Genetic studies have demonstrated that the Legionella genomes are highly plastic, with areas of the chromosome showing high levels of recombination as well as horizontal gene transfer both within and between species via plasmids. This, combined with various secretion systems and extensive effector repertoires that enable the bacterium to hijack host cell functions and resources, is instrumental in shaping its pathogenesis, survival and growth. Prevention of legionellosis is hampered by surveillance systems that are compromised by ascertainment bias, which limits commitment to an effective public health response. Current prevention strategies in Australia and New Zealand are directed at individual gardeners who use potting soils and compost. This consists of advice to avoid aerosols generated by the use of potting soils and use masks and gloves, but there is little evidence that this is effective. There is a need to better understand the epidemiology of L. longbeachae and other Legionella species in order to develop effective treatment and preventative strategies globally.

scholarly journals Impact of the COVID-19 nonpharmaceutical interventions on influenza and other respiratory viral infections in New Zealand

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Q. Sue Huang ◽  
◽  
Tim Wood ◽  
Lauren Jelley ◽  
Tineke Jennings ◽  
...  
Keyword(s):  
New Zealand ◽  
Pandemic Influenza ◽  
Viral Infections ◽  
Surveillance Systems ◽  
Respiratory Viral Infections ◽  
Nonpharmaceutical Interventions

AbstractStringent nonpharmaceutical interventions (NPIs) such as lockdowns and border closures are not currently recommended for pandemic influenza control. New Zealand used these NPIs to eliminate coronavirus disease 2019 during its first wave. Using multiple surveillance systems, we observed a parallel and unprecedented reduction of influenza and other respiratory viral infections in 2020. This finding supports the use of these NPIs for controlling pandemic influenza and other severe respiratory viral threats.

scholarly journals 66. Impact of a Pharmacist-Driven Azithromycin De-escalation Protocol for Community-Acquired Pneumonia

2020 ◽  
Vol 7 (Supplement_1) ◽  
pp. S52-S52
Author(s):  
Pegah Shakeraneh ◽  
Jeffrey Steele ◽  
Robert Seabury ◽  
Stephen J Thomas ◽  
Kristopher M Paolino ◽  
...  
Keyword(s):  
Legionella Pneumophila ◽  
Panel Member ◽  
Community Acquired Pneumonia ◽  
Hospital Length Of Stay ◽  
Post Intervention ◽  
Review Panel ◽  
Icu Patients ◽  
Significant Difference ◽  
Atypical Bacteria ◽  
Research Grant

Abstract Background Ceftriaxone and azithromycin are common empiric antibiotics for community-acquired pneumonia (CAP). Despite low suspicion for atypical infection, azithromycin is often continued for a full course. Negative laboratory data for atypical bacteria may assist with azithromycin de-escalation. Thus, a pharmacist-driven azithromycin de-escalation protocol was implemented for immunocompetent, non-intensive care unit (ICU) patients treated for CAP. The primary outcome was to compare azithromycin duration before and after protocol implementation. Secondary outcomes included hospital length of stay (LOS) and all-cause 30-day readmission. Methods This was a single-center, quasi-experimental study of hospitalized, non-ICU patients treated with azithromycin and a beta-lactam for CAP. The pre- and post-intervention cohorts were from 07/01/2018–04/30/2019 and 07/01/2019–04/30/2020, respectively. Patients were included if they were ≥18 years old, diagnosed with CAP, and had a negative Legionella pneumophila urinary antigen and negative nasopharyngeal swab PCR for Mycoplasma pneumoniae and Chlamydia pneumoniae. Patients were excluded if they were immunocompromised, admitted to an ICU, prescribed azithromycin for an alternative indication, or had evidence of atypical bacteria. Results After exclusion criteria were applied, 90 and 100 patients were included in the pre- and post-intervention cohorts, respectively. Demographic and clinical characteristics were mostly similar between cohorts. This initiative was associated with a statistically significant decrease in azithromycin duration (2 days (IQR 1–2.75) vs. 5 days (IQR 3–6), p < 0.001) and hospital LOS (3 days (IQR 2–5) vs. 5 days (IQR 3–8.25), p < 0.001). No statistically significant difference was observed for all-cause 30-day readmission (14 days (15.6%) vs 13 days (13.0%), p=0.614). Conclusion Implementation of a pharmacist-driven azithromycin de-escalation protocol for CAP was associated with reduced azithromycin duration and hospital LOS, but not all-cause 30-day readmission. Disclosures Jeffrey Steele, PharMD, Paratek Pharmaceuticals (Advisor or Review Panel member) Wesley D. Kufel, PharmD, Melinta (Research Grant or Support)Merck (Research Grant or Support)Theratechnologies, Inc. (Advisor or Review Panel member)

scholarly journals Viruses in community-acquired pneumonia in children aged less than 3 years old: High rate of viral coinfection

2008 ◽  
Vol 80 (10) ◽  
pp. 1843-1849 ◽  
Author(s):  
Gustavo Cilla ◽  
Eider Oñate ◽  
Eduardo G. Perez-Yarza ◽  
Milagrosa Montes ◽  
Diego Vicente ◽  
...  
Keyword(s):  
Community Acquired Pneumonia ◽  
High Rate ◽  
Viral Coinfection

scholarly journals MavN is aLegionella pneumophilavacuole-associated protein required for efficient iron acquisition during intracellular growth

2015 ◽  
Vol 112 (37) ◽  
pp. E5208-E5217 ◽  
Author(s):  
Dervla T. Isaac ◽  
Rita K. Laguna ◽  
Nicole Valtz ◽  
Ralph R. Isberg
Keyword(s):  
Legionella Pneumophila ◽  
Transmembrane Protein ◽  
Iron Acquisition ◽  
Broth Culture ◽  
Growth Defect ◽  
Secretion Systems ◽  
Intracellular Growth ◽  
Iron Starvation ◽  
Macrophage Infection ◽  
Intracellular Iron

Iron is essential for the growth and virulence of most intravacuolar pathogens. The mechanisms by which microbes bypass host iron restriction to gain access to this metal across the host vacuolar membrane are poorly characterized. In this work, we identify a unique intracellular iron acquisition strategy used byLegionella pneumophila.The bacterial Icm/Dot (intracellular multiplication/defect in organelle trafficking) type IV secretion system targets the bacterial-derived MavN (more regions allowing vacuolar colocalization N) protein to the surface of theLegionella-containing vacuole where this putative transmembrane protein facilitates intravacuolar iron acquisition. TheΔmavNmutant exhibits a transcriptional iron-starvation signature before its growth is arrested during the very early stages of macrophage infection. This intracellular growth defect is rescued only by the addition of excess exogenous iron to the culture medium and not a variety of other metals. Consistent with MavN being a translocated substrate that plays an exclusive role during intracellular growth, the mutant shows no defect for growth in broth culture, even under severe iron-limiting conditions. Putative iron-binding residues within the MavN protein were identified, and point mutations in these residues resulted in defects specific for intracellular growth that are indistinguishable from the ΔmavNmutant. This model of a bacterial protein inserting into host membranes to mediate iron transport provides a paradigm for how intravacuolar pathogens can use virulence-associated secretion systems to manipulate and acquire host iron.

scholarly journals Community-acquired pneumonia due to Legionella pneumophila, the utility of PCR, and a review of the antibiotics used

2011 ◽  
pp. 15 ◽  
Author(s):  
Paul Zarogoulidis ◽  
Gioulia Romanidou ◽  
EIRINI TERZI ◽  
Kostas Zarogoulidis ◽  
Ioanna Alexandropoulou
Keyword(s):  
Legionella Pneumophila ◽  
Community Acquired Pneumonia

scholarly journals Common Pathogens and Their Resistance to Antimicrobials in Community Acquired Pneumonia (CAP): A Single Center Study in Bangladesh

2020 ◽  
Vol 7 (12) ◽  
pp. 5144-5153
Author(s):  
Abu Kausar Mohammad ◽  
Morshed Nasir ◽  
Sujat Paul ◽  
Habibur Rahman ◽  
Kalam Abul ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Blood Culture ◽  
Legionella Pneumophila ◽  
Community Acquired Pneumonia ◽  
Hospitalized Patients ◽  
Sputum Culture ◽  
College Hospital ◽  
Cross Sectional ◽  
Female Ratio ◽  
Sensitivity Pattern

Pneumonia is a worldwide, serious threat to health and an enormous socio-economic burden for health care system. Community-acquired pneumonia (CAP) is associated with a significant mortality and morbidity. Knowledge of predominant microbial patterns in CAP constitutes the basis for initial decisions about empirical antimicrobial treatment. The aim of this study was to identify the bacterial etiology of CAP in adult hospitalized patients and to see their antibiotic sensitivity pattern. It was a hospital based cross sectional observational study on 87 hospitalized patients diagnosed with CAP admitted in Medicine department of Chittagong Medical College Hospital (CMCH). Sputum for Gram staining, Z N staining, culture sensitivity, blood culture and sensitivity and PCR for Legionella pneumophila, Mycoplasma pneumoniae, Chlamydophila pneumonia and Streptococcus pneumonia were done. Patients were followed up for in-hospital outcome and 30-day mortality. The mean (±SD) age was 49.59±16.97 years and male female ratio was 1.56:1. Sputum culture, blood culture and PCR were positive in 60.9%, 1.1% and 4.6% of the samples respectively. Klebsiella pneumoniae was identified in the sputum culture of the majority of the patients (39.1%), followed by Pseudomonas aeruginosa (10.3%), Staphylococcus aureus and Escherichia coli (5.7%). The only one sample which was positive in blood culture and it was Staphylococcus aureus. Streptococcus pneumoniae was identified in all the 4 PCR positive cases. The highly sensitive drugs were meropenem, levofloxacin and amikacin. In hospital mortality and 30-day mortality was 6.9% and 16.1% respectively. Gram-negative bacteria pre-dominate in the bacteriologic profile of CAP using conventional sputum and blood culture. There is need for further conventional serologic tests for atypical and viral pathogens in all patients admitted with CAP.

scholarly journals Community-acquired pneumonia caused by Legionella pneumophila (“Legionnaire's Disease”): a brief overview and clinical observation

2020 ◽  
Vol 30 (3) ◽  
pp. 350-360
Author(s):  
I. S. Tartakovskiу ◽  
S. A. Rachin ◽  
A. I. Sinopal'nikov ◽  
S. A. Rachina ◽  
Y. A. Yanovich ◽  
...  
Keyword(s):  
Legionella Pneumophila ◽  
Clinical Observation ◽  
Community Acquired Pneumonia ◽  
Legionnaire's Disease ◽  
Legionnaire’S Disease

scholarly journals Controlling membrane barrier during bacterial type-III protein secretion

2020 ◽  
Author(s):  
Svenja Hüsing ◽  
Ulf van Look ◽  
Alina Guse ◽  
Eric J. C. Gálvez ◽  
Emmanuelle Charpentier ◽  
...  
Keyword(s):  
Conformational Changes ◽  
High Speed ◽  
Membrane Integrity ◽  
Salt Bridge ◽  
High Rate ◽  
Salt Bridges ◽  
Secretion Systems ◽  
Bacterial Flagellum ◽  
Type Iii ◽  
Membrane Barrier

Type-III secretion systems (T3SSs) of the bacterial flagellum and the evolutionarily related injectisome are capable of translocating proteins with a remarkable speed of several thousand amino acids per second. Here, we investigated how T3SSs are able to transport proteins at such a high rate while preventing the leakage of small molecules. Our mutational and evolutionary analyses demonstrate that an ensemble of conserved methionine residues at the cytoplasmic side of the T3SS channel create a deformable gasket (M-gasket) around fast-moving substrates undergoing export. The unique physicochemical features of the M-gasket are crucial to preserve the membrane barrier, to accommodate local conformational changes during active secretion, and to maintain stability of the secretion pore in cooperation with a plug domain (R-plug) and a network of salt-bridges. The conservation of the M-gasket, R-plug, and salt-bridge network suggests a universal mechanism by which the membrane integrity is maintained during high-speed protein translocation in all T3SSs.

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