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Current Opinion in Infectious Diseases Aug 2003Hospital-acquired Legionnaires' disease is being increasingly discovered with the advent of rapid diagnostic techniques. This review examines both the clinical and... (Review)
Review
PURPOSE OF REVIEW
Hospital-acquired Legionnaires' disease is being increasingly discovered with the advent of rapid diagnostic techniques. This review examines both the clinical and political aspects of this important problem.
RECENT FINDINGS
New sources are being recognized, including the water supply of pediatric hospitals, long-term care facilities, and rehabilitation centers. Concern by the public, unfavorable publicity and litigation are now emerging as hospital-acquired Legionnaires' disease is coming under scrutiny by the lay media.
SUMMARY
Pro-active approaches to environmental detection and disinfection of hospital water systems are being demanded by public officials in place of the passive approach favored by many public health agencies.
Topics: Cross Infection; Disease Susceptibility; Disinfection; Hospitals; Humans; Legionnaires' Disease; Water Microbiology
PubMed: 12861086
DOI: 10.1097/00001432-200308000-00005 -
Clinical Microbiology Reviews Jan 1988In the summer of 1976, a mysterious epidemic of fatal respiratory disease in Philadelphia launched an intensive investigation that resulted in the definition of a new... (Review)
Review
In the summer of 1976, a mysterious epidemic of fatal respiratory disease in Philadelphia launched an intensive investigation that resulted in the definition of a new family of pathogenic bacteria, the Legionellaceae. In retrospect, members of the family had been isolated from clinical specimens as early as 1943. Unsolved epidemics of acute respiratory disease dating to the 1950s were subsequently attributed to the newly described pathogens. In the intervening years, the Legionellaceae have been firmly established as important causes of sporadic and epidemic respiratory disease. The sources of the infecting bacteria are environmental, and geographic variation in the frequency of infection has been documented. Airborne dissemination of bacteria from cooling towers and evaporative condensers has been responsible for some epidemics, but potable water systems are perhaps more important sources. The mode of transmission from drinking water is unclear. The Legionellaceae are gram-negative, facultative, intracellular pathogens. The resident alveolar macrophage, usually an effective antibacterial defense, is the primary site of growth. Cell-mediated immunity appears to be the most important immunological defense; the role of humoral immunity is less clear. Erythromycin remains the antibiotic of choice for therapy of infected patients, but identification and eradication of environmental sources are also essential for the control of infection.
Topics: Disease Outbreaks; History, 20th Century; Humans; Legionnaires' Disease; Philadelphia; United States
PubMed: 3060246
DOI: 10.1128/CMR.1.1.60 -
Journal of Thoracic Imaging Jul 1991The Legionella bacillus is a relatively common pulmonary pathogen that has been responsible for a number of outbreaks of respiratory illness this century. Not until... (Review)
Review
The Legionella bacillus is a relatively common pulmonary pathogen that has been responsible for a number of outbreaks of respiratory illness this century. Not until 1976, however, after exciting epidemiologic and microbiologic investigation, was the organism isolated and identified. Legionnaires' disease does not have a characteristic radiographic appearance, but certain features may alert the clinician to its presence. It often rapidly progresses to a lobar pneumonia that may not respond immediately to treatment. The radiographic findings lag behind clinical improvement, and radiographic resolution is prolonged. Organ transplantation patients often present with ill-defined, rounded, pleura-based opacities that may simulate pulmonary infarction and can cavitate.
Topics: Humans; Legionnaires' Disease; Radiography
PubMed: 1861275
DOI: 10.1097/00005382-199107000-00004 -
International Journal of Dermatology May 1983
Review
Topics: Adult; Aged; Disease Outbreaks; Erythromycin; Female; Humans; Legionella; Legionnaires' Disease; Male; Middle Aged; Radiography; Serologic Tests
PubMed: 6345418
DOI: 10.1111/j.1365-4362.1983.tb03376.x -
Clinical Infectious Diseases : An... Jun 1993
Review
Topics: Anti-Infective Agents; Disease Outbreaks; Erythromycin; Fluoroquinolones; Humans; Legionnaires' Disease; Trimethoprim, Sulfamethoxazole Drug Combination
PubMed: 8329504
DOI: 10.1093/clind/16.6.741 -
Archives of Internal Medicine Nov 1993Legionella pneumophila is associated with outbreaks of either Pontiac fever, a self-limited influenzalike condition without pneumonia, or Legionnaires' disease, a severe...
Legionella pneumophila is associated with outbreaks of either Pontiac fever, a self-limited influenzalike condition without pneumonia, or Legionnaires' disease, a severe pneumonic disease affecting elderly or immunocompromised individuals. An outbreak of both Legionnaires' disease and Pontiac fever after a point-source exposure to L pneumophila was studied. Our observations demonstrated the spectrum of illness that L pneumophila may cause and emphasized the importance of host factors in affecting the expression of infection.
Topics: Adult; Baths; Disease Outbreaks; Humans; Legionnaires' Disease; Male; Vermont; Water Microbiology
PubMed: 8239853
DOI: 10.1001/archinte.153.22.2597 -
Journal of Environmental Health 1986Legionellosis (Legionnaires' disease and Pontiac fever) outbreaks have been associated with aerosols ejected from contaminated cooling towers--wet-type heat rejection...
Legionellosis (Legionnaires' disease and Pontiac fever) outbreaks have been associated with aerosols ejected from contaminated cooling towers--wet-type heat rejection units (WTHRUs) used to dissipate unwanted heat into the atmosphere. The Vermont Department of Health undertook a program to inventory, inspect, and sample all WTHRUs in Vermont from April 1981 to April 1982. All WTHRUs were sampled for Legionella pneumophila and data were obtained for location, design, construction, and operating characteristics. Of the 184 WTHRUs operating, statistical analyses were performed on those 130 which were sampled for L. pneumophila only once during the study period. Of these, 11 (8.5%) were positive for L. pneumophila. Sources of makeup water and period of operation had significant association with the recovery of L. pneumophila. Five out of 92 towers (5.4%) utilizing surface water sources for cooling were positive for L. pneumophila, in contrast to 6 positive towers of the 38 units (15.8%) which obtained makeup water from ground water sources (p = .054 by chi-square test). Nearly 15% of the 54 units which operated throughout the year were positive, compared to less than 4% of the 76 towers operating seasonally (p = .03 by chi-square test). The mean pH of the cooling water in units where L. pneumophila was recovered (8.3) was significantly higher than the mean pH of 7.9 in units testing negative (p less than .05 by t-test). In addition, the mean log-transformed turbidity of positive towers, 0.03 nephelometric units (ntu), was significantly lower than the mean of log turbidity of negative towers, 0.69 ntu (p less than .02 by t-test).
Topics: Air Conditioning; Data Collection; Environmental Exposure; Humans; Legionnaires' Disease; Maintenance and Engineering, Hospital; Vermont; Water Microbiology
PubMed: 10281778
DOI: No ID Found -
Microbial Genomics Mar 2023are host-adapted bacteria that infect and reproduce primarily in amoeboid protists. Using similar infection mechanisms, they infect human macrophages, and cause...
are host-adapted bacteria that infect and reproduce primarily in amoeboid protists. Using similar infection mechanisms, they infect human macrophages, and cause Legionnaires' disease, an atypical pneumonia, and the milder Pontiac fever. We hypothesized that, despite the similarities in infection mechanisms, the hosts are different enough that there exist high-selective value mutations that would dramatically increase the fitness of inside the human host. By comparing a large number of isolates from independent infections, we identified two genes, mutated in three unrelated patients, despite the short duration of the incubation period (2-14 days). One is a gene coding for an outer membrane protein (OMP) belonging to the OmpP1/FadL family. The other is a gene coding for an EAL-domain-containing protein involved in cyclic-di-GMP regulation, which in turn modulates flagellar activity. The clinical strain, carrying the mutated EAL-domain-containing homologue, grows faster in macrophages than the wild-type strain, and thus appears to be better adapted to the human host. As human-to-human transmission is very rare, fixation of these mutations into the population and spread into the environment is unlikely. Therefore, parallel evolution - here mutations in the same genes observed in independent human infections - could point to adaptations to the accidental human host. These results suggest that despite the ability of to infect, replicate in and exit from macrophages, its human-specific adaptations are unlikely to be fixed in the population.
Topics: Humans; Legionella pneumophila; Legionella; Legionnaires' Disease; Macrophages
PubMed: 36947445
DOI: 10.1099/mgen.0.000958 -
The American Review of Respiratory... Jun 1977
Topics: Disease Outbreaks; Humans; Legionnaires' Disease; Pennsylvania
PubMed: 262103
DOI: 10.1164/arrd.1977.115.6.911 -
British Medical Journal Nov 1978
Topics: Adult; Aged; Disease Outbreaks; Female; Humans; Legionnaires' Disease; Male; Middle Aged; United Kingdom; United States
PubMed: 719378
DOI: No ID Found