Legionnaires’ Disease
Asif Khan
Biology 065
April 15, 2010
Background
July 21st, 1976: First Discovered at the
American Legion Convention.
 August 2nd, 1976: Tort Claim Act (50 million
doses)
Mist of Confusion
Early 1977: Dr. Joseph McDade
Legionella pneumophilia: the Legions; “lungloving” as it infects alveolar macrophages.
BBC (editor). (2003). Legionnaires’ Disease-a History of its Disocvery. BBC. Retrieved from:
…..http://www.bbc.co.uk/dna/h2g2/A882371
Image Courtesy:
http://www.phoenixmasonry.org/masonicmuseum/fraternalism/images/American_legion_color_emblem.jpg
Environment
Dr. Carl Fliermans: lipids of
L.pneumophilia resembled those of
thermophilic bacteria.
Grows best in warm water sources such
as: hot tubs, cooling towers, hot water
tanks, large plumbing systems, or parts of
the air-conditioning systems of large
buildings.
BBC (editor). (2003). Legionnaires’ Disease-a History of its Disocvery. BBC. Retrieved from:
…..http://www.bbc.co.uk/dna/h2g2/A882371
Image Courtesy: http://www.britishcouncil.org/science-dv-climate-330x270-cooling-towers.jpg
Environment
Hilbi, H et al. (2010). Update on Legionnaires’ disease: pathogenesis, epidemiology, detection and control.
Molecular Microbiology. Micromeeting 71 [1] p 2.
Infectious Agent
A thin and flagellated gram-negative
bacterium.
Non-capsulated rod-like bacteria.
Dot/Icm secretion system to inject large
numbers of protein effectors into the host
cells.
Pseudopod acts as a phagocytosis.
Incubation period: two to ten days.
Madigan M and Martinko J (editors). (2005). Brock Biology of Microorganisms (11th ed.).
…..Prentice Hall.
Image courtesy: http://www.aquatreat.co.uk/aquatreat/LEGIONNAIRES%27%20DISEASE.jpg
Risk Factors
Opportunistic Disease: underlying illness/weak immune
system.
Nosocomial infections are major concerns.
Middle-aged, elderly, COPD, smokers and other genetic
susceptible patients are primary targets.
OSHA (editor). (2007). LEGIONNAIRES' DISEASE: QUESTIONS AND ANSWERS. U.S. Department of Labor
…...Occupational Safety &.Health Administration. Retrieved from:
…..http://www.osha.gov/dts/osta/otm/otm_iii/otm_iii_7.html#1
Image Courtesy: http://www.childrenshospital.org/chnews/10-12-05/images/handHygieneFact298.gif
Symptoms
Early Symptoms
Malaise, muscle aches, lethargy and slight headaches.
High Fever, non-productive cough, abdominal pain, diarrhea.
Late Symptoms
Extreme lethargy, comatose state
Impaired kidney and liver functioning
Nervous System disorders
Bartram, J et al. (2007). Legionella and the prevention of legionellosis. World Health
…..Organization. WHO Press: India. p. 1-27
Imperiale T.F., Gupta S.K. and Sarosi G.A. (2001). Evaluation of the Winthrop-University
…..Hospital criteria to identify Legionella pneumonia. Chest, 120(4):1064–1071.
OSHA (editor). (2009). Legionnaires’ Disease. U.S. Department of Labor Occupational Safety &
…..Health Administration. Retrieved from:
…..http://www.osha.gov/dts/osta/otm/legionnaires/faq.html
Diagnosis
Urinary Antigen Test
The serogroup of Legionella often times overlap with other
immunocompromised diseases.
Culture
Lung biopsy, respiratory secretions, sputum
Less preferable technique
CDC (Editor). 2008. Patient Facts: Learn More about Legionnaires' disease. Centers for Disease …..Control and
Prevention. Retried from: http://www.cdc.gov/legionella/patient_facts.htm
Rathore, M. H. (2009). Legionella Infection: Treatment & Medication
…..Emedicine from WebMD. Retrieved from: http://emedicine.medscape.com/article/965492
Photo Courtesy: http://www.alere.co.uk/images/product/thumbs/1_prod_4f15ebc716c482f10018f230ab1bb8cd.gif
Transmission
L. pneumophilia is NOT spread by human-human interaction.
Mist or vapor contaminated with the bacteria.
Warm stagnant water (90-122 F) in complex systems is ideal.
OSHA (editor). (2007). LEGIONNAIRES' DISEASE: QUESTIONS AND ANSWERS. U.S. Department
…..of Labor Occupational Safety &.Health Administration. Retrieved from:
…..http://www.osha.gov/dts/osta/otm/otm_iii/otm_iii_7.html#1
Incidence
8,000 to 18,000 people are hospitalized in US with more than
4,000 deaths.
32,000 cases between1995 and 2005.
Potential major outbreaks with the retiring baby boomers?
EWGLI (editor). (2009). About Legionnaires' Disease (Legionellosis). The European Working
…..Group for Legionella Infections. Retrieved from:
…..http://www.ewgli.org/data/factsheets/about_ld.htm#Outbreaks
Treatment
Wide-range antibiotics to treat pneumonia
Fluoroquinolones (levofloxacin,
moxifloxacin)
Macrolides (azithromycin)
Mechanism
Quinolones: DNA gyrase inhibitors
Macrolides: binds to 50S subunit of
ribosomes
CDC (Editor). 2008. Patient Facts: Learn More about Legionnaires' disease. Centers for Disease …..Control and
Prevention. Retried from: http://www.cdc.gov/legionella/patient_facts.htm
Rathore, M. H. (2009). Legionella Infection: Treatment & Medication
…..Emedicine from WebMD. Retrieved from: http://emedicine.medscape.com/article/965492
Photo Courtesy: http://imghost1.indiamart.com/data2/KF/CB/MY-1678174/2macrolides-drugs-250x250.jpg
Prevention
Regularly maintain and clean cooling towers and evaporative condensers
to prevent growth of Legionnaires’ disease Bacteria (LDB). This should
include twice-yearly cleaning and periodic use of chlorine or other effective
biocide.
Maintain domestic water heaters at 60°C (140°F). The temperature of
the water should be 50°C (122°F) or higher at the faucet.
Avoid conditions that allow water to stagnate. Large water-storage tanks
exposed to sunlight can produce warm conditions favorable to high levels of
LDB. Frequent flushing of unused water lines will help alleviate stagnation.
OSHA (editor). (2009). Legionnaires’ Disease. U.S. Department of Labor Occupational Safety &
…..Health Administration. Retrieved from: http://www.osha.gov/dts/osta/otm/legionnaires/faq.html
Future
No evidence of drug-resistance
Survival techniques both inside and outside of the human
environment is remarkable. Hence, Legionella pneumophilia is here
to stay.
Treatment can effectively treat yet prevention is always better.
References
Barbaree, J. M., Breiman R. F., Dufour A. P. (1993). Legionella: Current Status and Emerging …..Perspectives - American Society for
Microbiology, Washington DC
Bartram, J et al. (2007). Legionella and the prevention of legionellosis. World Health …..Organization. WHO Press: India. p. 1-27
BBC (editor). (2003). Legionnaires’ Disease-a History of its Disocvery. BBC. Retrieved from: …..http://www.bbc.co.uk/dna/h2g2/A882371
CDC (Editor). 2008. Patient Facts: Learn More about Legionnaires' disease. Centers for Disease …..Control and Prevention. Retried from:
http://www.cdc.gov/legionella/patient_facts.htm
EWGLI (editor). (2009). About Legionnaires' Disease (Legionellosis). The European Working …..Group for Legionella Infections.
Retrieved from: …..http://www.ewgli.org/data/factsheets/about_ld.htm#Outbreaks
Fitzgeorge RB et al. (1983). Aerosol infection of animals with strains of Legionella pneumophila
…..of different virulence: comparison with intraperitoneal and intranasal routes of infection.
…..Journal of Hygiene, London, 90(1):81–89.
Imperiale T.F., Gupta S.K. and Sarosi G.A. (2001). Evaluation of the Winthrop-University …..Hospital criteria to identify Legionella
pneumonia. Chest, 120(4):1064–1071.
Madigan M and Martinko J (editors). (2005). Brock Biology of Microorganisms (11th ed.). …..Prentice Hall.
OSHA (editor). (2009). Legionnaires’ Disease. U.S. Department of Labor Occupational Safety & …..Health Administration. Retrieved
from: …..http://www.osha.gov/dts/osta/otm/legionnaires/faq.html
OSHA (editor). (2007). LEGIONNAIRES' DISEASE: QUESTIONS AND ANSWERS. U.S. …..Department of Labor Occupational Safety
&.Health Administration. Retrieved from: …..http://www.osha.gov/dts/osta/otm/otm_iii/otm_iii_7.html#1
Rathore, M. H. (2009). Legionella Infection: Treatment & Medication
…..Emedicine from WebMD. Retrieved from: http://emedicine.medscape.com/article/965492
Swanson M and Heuner K (2008). Legionella: Molecular Microbiology. Caister Academic Press.
Special Thanks to
Christopher Hurt, MD. Clinical Instructor UNC School of Medicine.
Specialized in Internal Medicine. RESEARCH SUMMARY: Acute HIV
infection, transmission of antiretroviral drug resistance, substance
use/abuse and HIV risk, and behavioral approaches to secondary HIV
prevention. Detailed information can be obtained here:
http://www.med.unc.edu/infdis/faculty/christopher-hurt-md
Joseph P. Vogel. Department of Molecular Microbiology. Washington
University School of Medicine Ph.D., Molecular Biology Princeton
University, NJ. Research Intersest:
“The key to Legionella virulence is its ability to survive and replicate
within alveolar macrophages. In order to accomplish this, Legionella
uses a specialized secretion system called "Dot/Icm" to inject a large
number of protein effectors into it's host cell.”
Detailed information can be obtained here:
http://microbiology.wustl.edu/Bio_Sketches/vogelCV.html