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Seminars in Cell & Developmental Biology Dec 2022Legionella pneumophila, a Gram-negative intracellular bacterium, is one of the major causes of Legionnaires' disease, a specific type of atypical pneumonia. Despite... (Review)
Review
Legionella pneumophila, a Gram-negative intracellular bacterium, is one of the major causes of Legionnaires' disease, a specific type of atypical pneumonia. Despite intensive research efforts that elucidated many relevant structural, molecular and medical insights into Legionella's pathogenicity, Legionnaires' disease continues to present an ongoing public health concern. Legionella's virulence is based on its ability to simultaneously hijack multiple molecular pathways of the host cell to ensure its fast replication and dissemination. Legionella usurps the host ubiquitin system through multiple effector proteins, using the advantage of both conventional and unconventional (phosphoribosyl-linked) ubiquitination, thus providing optimal conditions for its replication. In this review, we summarize the current understanding of L. pneumophila from medical, biochemical and molecular perspectives. We describe the clinical disease presentation, its diagnostics and treatment, as well as host-pathogen interactions, with the emphasis on the ability of Legionella to target the host ubiquitin system upon infection. Furthermore, the interdisciplinary use of innovative technologies enables better insights into the pathogenesis of Legionnaires' disease and provides new opportunities for its treatment and prevention.
Topics: Humans; Bacterial Proteins; Host-Pathogen Interactions; Legionella pneumophila; Legionnaires' Disease; Ubiquitin
PubMed: 35177348
DOI: 10.1016/j.semcdb.2022.02.008 -
Epidemiology and Infection Jul 2023Over the past two decades, the incidence of legionellosis has been steadily increasing in the United States though there is noclear explanation for the main factors... (Review)
Review
Over the past two decades, the incidence of legionellosis has been steadily increasing in the United States though there is noclear explanation for the main factors driving the increase. While legionellosis is the leading cause of waterborne outbreaks in the US, most cases are sporadic and acquired in community settings where the environmental source is never identified. This scoping review aimed to summarise the drivers of infections in the USA and determine the magnitude of impact each potential driver may have. A total of 1,738 titles were screened, and 18 articles were identified that met the inclusion criteria. Strong evidence was found for precipitation as a major driver, and both temperature and relative humidity were found to be moderate drivers of incidence. Increased testing and improved diagnostic methods were classified as moderate drivers, and the ageing U.S. population was a minor driver of increasing incidence. Racial and socioeconomic inequities and water and housing infrastructure were found to be potential factors explaining the increasing incidence though they were largely understudied in the context of non-outbreak cases. Understanding the complex relationships between environmental, infrastructure, and population factors driving legionellosis incidence is important to optimise mitigation strategies and public policy.
Topics: United States; Humans; Incidence; Legionellosis; Disease Outbreaks; Temperature; Legionnaires' Disease
PubMed: 37503568
DOI: 10.1017/S0950268823001206 -
Infectious Disease Clinics of North... Mar 2017Legionella pneumophila is one of the more recently discovered bacterial pathogens of humans. The last 2 decades have seen tremendous progress in the evolution of... (Review)
Review
Legionella pneumophila is one of the more recently discovered bacterial pathogens of humans. The last 2 decades have seen tremendous progress in the evolution of diagnostic tests, for detection and characterization of this pathogen and for defining the host response to infection. This has generated several diagnostic tools that span the range from simple immunologic assays to modern genome sequencing. This review describes the state of affairs of this continuously evolving field regarding the diagnosis of Legionnaire's disease and covers detection, assessment of antibiotic susceptibility, and epidemiologic characterization of isolates of L pneumophila and other pathogenic species within the genus.
Topics: Algorithms; Anti-Bacterial Agents; Antigens, Bacterial; Bacteriological Techniques; DNA, Bacterial; Humans; Legionella pneumophila; Legionnaires' Disease; Microbial Sensitivity Tests; Sequence Analysis, DNA
PubMed: 27979684
DOI: 10.1016/j.idc.2016.10.012 -
Przeglad Epidemiologiczny 2019The aim of this study is to assess the epidemiological situation of legionellosis in Poland in 2017 in comparison with previous years.
OBJECTIVE
The aim of this study is to assess the epidemiological situation of legionellosis in Poland in 2017 in comparison with previous years.
MATERIAL AND METHODS
The analysis is based on national surveillance data published in the annual bulletin: “Infectious diseases and poisonings in Poland in 2017” and bulletins from previous years along with data from legionellosis case reports collected and sent to the Department of Epidemiology of Infectious Diseases and Surveillance NIPH – NIH by Sanitary and Epidemiological Stations.
RESULTS
In Poland, both cases of Legionnaires’ disease (an acute form of infection with pneumonia) and Pontiac fever (a mild, influenza-like form of infection) are routinely reported to the surveillance system. In 2017, a total of 39 cases of legionellosis were registered, including 38 cases of Legionnaires’ disease and 1 case of Pontiac fever; the annual incidence rate 0.102 (per 100,000 population) has increased by almost 50 percent since previous year (0.070) and is almost three times higher than the median incidence (0.036) for 2011-2015. The infections were reported in fourteen voivodeships; only one voivodeship (Świętokrzyskie) did not register any case in last years. The incidence in men (0.129 per 100,000) was higher compared to women (0.076); the highest incidence (0.323) was noted in men aged 50-59. All reported cases were sporadic and were hospitalised. The Sanitary Inspection reported nine fatal cases – 6 women and 3 men. Thirty three cases were autochthonous including four cases linked with contaminated water systems in health-care settings. Six cases were associated with travels abroad (to Egypt, Albania, Italy and Crete).
SUMMARY AND CONCLUSIONS
Although in recent years number of reported cases continues to rise, the incidence of legionellosis in Poland remains one of the lowest in the entire EU. Also draws attention variation of incidence between provinces and a high mortality among reported cases. Our data suggest significant under-diagnosis of legionellosis. A priority remains to improve early diagnosis of Legionnaires’ disease in health care settings.
Topics: Adolescent; Adult; Aged; Aged, 80 and over; Child; Child, Preschool; Female; Humans; Incidence; Legionellosis; Legionnaires' Disease; Male; Middle Aged; Poland; Registries; Young Adult
PubMed: 31385671
DOI: 10.32394/pe.73.26 -
JAAPA : Official Journal of the... Oct 2022Legionnaires disease is an important, relatively uncommon, yet well known form of atypical community-acquired pneumonia (CAP). If not appropriately treated in the early... (Review)
Review
Legionnaires disease is an important, relatively uncommon, yet well known form of atypical community-acquired pneumonia (CAP). If not appropriately treated in the early stage of infection, it can be fatal. Several factors increase the risk of contracting Legionnaires disease, including age over 50 years, chronic cardiovascular disease, underlying respiratory disease, chronic renal disease, diabetes, smoking, any immunosuppressing condition, travel history, and certain types of employment. Legionnaires disease can present without the usual symptoms associated with pneumonia. The incidence of Legionnaires disease is increasing, and because of its morbidity and mortality, clinicians should consider it in the differential when treating patients with CAP. This article reviews the pathophysiology and treatment of Legionnaires disease and when to refer patients to tertiary centers for higher levels of care, including extracorporeal membrane oxygenation.
Topics: Community-Acquired Infections; Extracorporeal Membrane Oxygenation; Humans; Legionella; Legionnaires' Disease; Middle Aged; Pneumonia
PubMed: 36165547
DOI: 10.1097/01.JAA.0000873792.00538.78 -
Frontiers in Cellular and Infection... 2018
Topics: Acanthamoeba; Biomedical Research; DNA Mutational Analysis; Host-Pathogen Interactions; Legionella; Legionnaires' Disease; Microbial Viability; Virulence; Virulence Factors; Water Microbiology
PubMed: 30283746
DOI: 10.3389/fcimb.2018.00328 -
Praxis 2020CME: Legionella pneumonia Legionnaire's disease is a usually severe form of pneumonia caused by Legionella pneumophila, a Gram-negative bacterium with an airborne...
CME: Legionella pneumonia Legionnaire's disease is a usually severe form of pneumonia caused by Legionella pneumophila, a Gram-negative bacterium with an airborne transmission. The infection is acquired in the community, but cases of hospital acquisition from hot water systems have been described. The most common clinical features are cough, fever, gastrointestinal symptoms, hyponatremia and altered liver function tests. The mainstay investigations to confirm diagnosis are urine antigen, sputum polymerase chain reaction, sputum or bronchial alveolar lavage cultures. Standard antibiotic treatment are macrolides or fluoroquinolones.
Topics: Anti-Bacterial Agents; Humans; Legionella pneumophila; Legionnaires' Disease; Pneumonia; Polymerase Chain Reaction
PubMed: 32517597
DOI: 10.1024/1661-8157/a003467 -
Current Issues in Molecular Biology 2021Legionnaires' disease and Pontiac fever are both diseases with important public health implications and require prompt and thorough responses to outbreaks for future...
Legionnaires' disease and Pontiac fever are both diseases with important public health implications and require prompt and thorough responses to outbreaks for future prevention. Effective methods for defining, diagnosing, reporting and responding to legionellosis outbreaks ideally should be standardized across countries. Therefore, the European Union surveillance methods for countering Legionnaires' disease is a useful model especially for travel-associated Legionnaires' disease (TALD) cases which are on the rise. Multi-country surveillance in the EU and European Economic Area (EEA) has evolved since the first organizational efforts in the 1980's to the currently responsible, European Legionnaires' Disease Surveillance Network (ELDSNet). This chapter outlines the practices of the EU surveillance of Legionnaires' disease including their schemata, definitions, responsibilities of participating members, methods and the results of the data collected since the program's inception. Lastly, improvements must still be made as the incidence of Legionnaires' disease in the EU is likely underestimated due to underreporting and/or underdiagnosis. Nearly 70% of cases are reported from only four countries, France, Germany, Italy and Spain, which represent 50% of the EU population.
Topics: Disease Outbreaks; Europe; Humans; Legionella; Legionnaires' Disease; Public Health Surveillance
PubMed: 33284133
DOI: 10.21775/cimb.042.081 -
Annals of Clinical Microbiology and... Aug 2017Legionnaires' disease is commonly diagnosed clinically using a urinary antigen test. The urinary antigen test is highly accurate for L. pneumophila serogroup 1, however... (Review)
Review
Legionnaires' disease is commonly diagnosed clinically using a urinary antigen test. The urinary antigen test is highly accurate for L. pneumophila serogroup 1, however other diagnostic tests should also be utilized in conjunction with the urinary antigen as many other Legionella species and serogroups are pathogenic. Culturing of patient specimens remains the gold standard for diagnosis of Legionnaires' disease. Selective media, BYCE with the addition of antibiotics, allows for a high sensitivity and specificity. Culturing can identify all species and serogroups of Legionella. A major benefit of culturing is that it provides the recovery of a patient isolate, which can be used to find an environmental match. Other diagnostic tests, including DFA and molecular tests such as PCR and LAMP, are useful tests to supplement culturing. Molecular tests provide much more rapid results in comparison to culture, however these tests should not be a primary diagnostic tool given their lower sensitivity and specificity in comparison to culturing. It is recommended that all laboratories develop the ability to culture patient specimens in-house with the selective media.
Topics: Antigens, Bacterial; Culture Media; Diagnostic Tests, Routine; Humans; Legionella pneumophila; Legionnaires' Disease; Polymerase Chain Reaction; Respiratory System; Sensitivity and Specificity
PubMed: 28851372
DOI: 10.1186/s12941-017-0229-6 -
The New England Journal of Medicine Dec 2021
Topics: Diagnosis, Differential; Female; Humans; Legionella pneumophila; Legionnaires' Disease; Lung; Middle Aged; Radiography, Thoracic
PubMed: 34874634
DOI: 10.1056/NEJMcps2108991