LEGIONNAIRE’S DISEASE Dr. Ramkesh Prasad Department of Community Medicine Gauhati Medical College
LEGIONNAIRE’S DISEASE
Dr. Ramkesh Prasad
Department of Community Medicine
Gauhati Medical College
Legionnaire’s Disease
Caused by Legionella pneumophila Ranks fourth among the causes of
pneumonia(S. pneumoniae, H. influenzae,
Chlamydophila pneumoniae ) One of the atypical pneumonias, Gram
stained sputum smear does not show organisms.
Prevalent worldwide
Epidemiology
Each year, between 8,000 and 18,000 people are hospitalized with Legionnaires' disease in the U.S.
While Legionellae are ubiquitous in freshwater environments, and likely have been for centuries, it is their unique growth requirements in the environment coupled with the advent of human technology favoring complex water systems that has led to the designation of legionellosis as an emerging infectious disease in the late twentieth century.
Outbreaks
Year City Venue Source Cases Deaths
Fatality rate
July 1973 Benidorm, Spain Rio Park Hotel Not known 4 4 100%
July 1976
Philadelphia, Pennsylvania
Bellevue-Stratford Hotel
Air conditioning 221 34 15.4%
April 1985
Stafford, England
Stafford District Hospital
Air conditioning 175 28 16.0%
March 1999
Bovenkarspel, Netherlands
Westfrisian Flora flower exhibition
Hot tub 318 32 10.0%
2005 Toronto, CanadaSeven Oaks
Home for the Aged
Cooling tower 127 21 16.5%
OutbreaksYear City Venue Source Cases
Deaths
Fatality rate
April 2000
Melbourne Australia
Melbourne Aquarium
Cooling tower 95
July 2001
Murcia, Spain Hospital Cooling towers800
(449)10 17.8%
2002Barrow –in-
FurnessBarrow –in-
FurnessAir
conditioning172 7 4.1%
2005Fredrikstad,
NorwayFactory Air scrubber 56 4 4.2%
2008 New JerseySaint Peter’s University Hospital
Drinking water 6 3 0.3%
Feb 2012
Calp, SpainAR Diamante Beach Hotel
Not known 14 3 17%
HISTORYThe 1976 Philadelphia epidemic Legionnaires' disease was first recognized
as a distinct entity during an epidemic of pneumonia that occurred in Philadelphia, in the July1976. About 4,000 members of the Pennsylvania
State American Legion, an organization of former military veterans, met in July for American Bicentennial celebration, which lasted from 21 - 24 July.
On 27th July, one of the legionnaire died of a pneumonia like illness
On 30th July a physician in Bloomsburg, realized that the 3
patients he was treating from similar condition had all attended
the convention
On the same day, a nurse in Chambersburg Hospital noted a
similar condition in 3 patients who had gone to the convention
By Aug 2nd it was realized that there was some undeniable
connection
By August, 18 legionnaires had already died, it attracted huge
media coverage Out of the 221 cases - 72 were people who were not involved in
the American Legion convention - people who had either been inside the Bellevue Stratford Hotel, or had walked past it.
On January 18, 1977 CDC announced that the cause of
Legionnaire’s disease was isolated. (Thanks to the works of Dr
Joseph McDade * )
The source of the breeding site of the organism traced to the
cooling towers that were connected to the air conditioners of the
hotel.
Agent Legionella pneumophila Gram negative, aerobic bacteria bacterial cells are 0.5–1 µm wide and 2–50
µm long and motile, with one or more polar or lateral flagella
Ubiquitous worldwide Do not grow on routine microbiologic media. Requires Iron, L cystiene and temperature
25-45 °C Grown on Buffered charcoal yeast extract
(BCYE) agar medium.
Breeding grounds
Found in lakes, streams, and other bodies of water,
Grows inside free living ameba (Acanthameba,
Naegleria, Hartmannell)
Grows best in warm water, like in hot tubs, cooling towers, hot water tanks, large plumbing systems, or parts of the air-conditioning systems of large buildings. Indoor ornamental fountains have been confirmed as a
cause of Legionnaires' disease outbreaks, in which submerged lighting as a heat source was attributed to the outbreak in all documented cases.
HostRisk Factors Age: Elderly are more susceptible cigarette smoking; chronic lung disease; advanced age; Immunosuppression/immunodeficiency
transplantation, HIV infection treatment with glucocorticoids or tumor
necrosis factor antagonists
Transmission Inhalation of Legionellae in aerosolized droplets is the primary means of
transmission
These aerosolized droplets must be of a respirable size (1–5 μm).
No person-to-person transmission of Legionnaires’ disease has been
documented.
A number of devices have been implicated as sources of aerosol transmission
of Legionellae.
These sources are associated with both potable and non-potable water.
Sources producing aerosols of contaminated potable water include
showers, faucets, and respiratory therapy equipment.
Sources utilizing non-potable water include cooling towers, heated spas,
decorative fountains, humidifiers, ultrasonic mist machines, and
industrial manufacturing systems.
Disease occurs after exposure to aquatic settings that promote
bacterial growth—the aquatic environment is somewhat stagnant,
the water is warm (25°C – 42°C), the water must be aerosolized so that the
bacteria can be inhaled into the lungs
These 3 conditions are met almost exclusively in developed or industrialized settings
Pathogenesis
Legionella enters the lungs through aspiration or direct inhalation.
Attachment to host cells is mediated by bacterial type IV pili, heat-shock proteins, a major outer-membrane protein, and complement.
Because the organism possesses pili that mediate adherence to respiratory tract epithelial cells, conditions that impair mucociliary clearance, including cigarette smoking, lung disease, or alcoholism, predispose to Legionnaires' disease.
Clinical Feature
Fever
Pleurisy
Grossly purulent sputum
Diarrhoea
Renal failure
Diagnosis
Chest X-ray Culture
Sputum Tracheal Aspirate
Direct fluorescent antibody staining of sputum
Urinary antigen testing Antibody serolgy - fourfold
seroconversion
Treatment
Macrolide: Azithromycin, Clarithromycin,
Fluoroquinolones: Levofloxacin,
Ciprofloxacin, Moxifloxacin, Levofloxacin
Tetracycline,
Prognosis
Mortality rates vary with patient's underlying disease and its severity, the patient's immune status, the severity of pneumonia, and the timing of administration of appropriate
antimicrobial therapy. With appropriate and timely antibiotic
treatment, mortality rates in immunocompetent patients range from 0 to 11%; without treatment, the figure may be as high as
31%
Prevention There is no vaccine for legionellosis, Antibiotic prophylaxis is not effective always.
Travelers at increased risk for infection, such as the elderly or those with immunocompromising conditions such as cancer or diabetes, may choose to avoid high-risk areas, such as whirlpool spas.
If exposure cannot be avoided, travelers should be advised to seek medical attention promptly if they develop symptoms of Legionnaires’ disease or Pontiac fever
Chemoprophylaxis with a macrolide antibiotic has been effective in immunocompromised patients during nosocomial epidemics of the disease
Routine environmental culture of hospital water supplies is recommended as an approach to the prevention of hospital-acquired Legionnaires' disease
Hyperchlorination and superheating of water
can help control the multiplication of legionellae
in water and in air-conditioning systems.
Use of monochloramine, rather than chlorine to
treat public drinking water to reduce
colonization
Proper building and plumbing design and
construction can reduce frequency and intensity
of L. pneumophila contamination of potable
water.
Proper insulation of hot water pipes to prevent
warming of water in adjacent cold water pipes.
Maintaining hot water temperature above 50 °C
and cold water below 20 °C
Recreational spas must be properly constructed,
regularly maintained and closely monitored to
prevent high level of bacterial growth.
Pontiac Fever
An acute, self-limiting, flu-like illness with
an incubation period of 24–48 h.
Pneumonia does not develop.
Malaise, fatigue, and myalgia are the
most common symptoms.
Complete recovery occurs within a few
days; antibiotic therapy is unnecessary.
Legionnaire’s Disease in India
Agrawal L, Dhunjibhoy KR, Nair KG. Isolation of Legionella pneumophila from patients of respiratory tract disease and environmental samples. Indian J Med Res 1991; 93: 364-5.
In this preliminary study, 45 patients suffering from pneumonia were screened for L. pneumophila.
17 random environmental samples, water from a cooling system used for air conditioning units, and samples from a respirator-humidifier were screened.
Four of the 45 clinical specimens (9 %) and 13 of the 17 environmental samples (76 %) showed the presence of L. pneumophila. This is the 1st report from India of the isolation of L. pneumophila
Chaudhry R, Dhawan B, Dey AB. The incidence of Legionella pneumophila: a prospective study in a tertiary care hospital in India. Trop Doct 2000; 30: 197-200.
Between April 1997 and December 1998, 60 patients with CAP
admitted to the All India Institute of Medical Sciences were
included in the study.
Etiological diagnosis was based on the results of routine
microbiological blood culture for bacteria and serological test
by ELISA for L. pneumophila serogroup 1-7.
Eight patients (13 %) had a conventional bacterial etiology and
9 patients (15 %) had serological evidence of recent infection
with L. pneumophila.
Legionnaire’s Disease in India
Sero diagnosis of Legionella infection in community acquired pneumonia, Sabah Javed, Rama Chaudhry, Kapil Passi, Sutikshan Sharma, Padmaja K., Benu Dhawan & A.B. Dey, Indian J Med Res 131, January 2010, pp 92-96
All 113 clinical samples of paediatric (27) and adult (86) patients were collected during May 2005 to January 2008 on their first visit to the AIIMS, New Delhi, with the symptoms of pneumonia
Thirty one of the 113 cases (27.43%) were
serologically positive.
Isolation of Legionella pneumophila from clinical & environmental sources in a tertiary care hospital, S. Anbumani, A. Gururajkumar & A. Chaudhury, Indian J Med Res 131, June 2010, pp 761-764
Study done at Sri Venkateswara Institute of Medical Sciences, Tirupati, India
A total of 470 lower respiratory tract samples and 24 water samples from hospital outlets were examined. Culture was done on buffered charcoal yeast extract agar with supplements and identification of the isolates was done by microscopy and biochemical tests.
L. pneumophila could be isolated from 12 (2.55%) patients suffering from community-acquired lower respiratory tract infection, unassociated with other aetiological agents of bacterial pneumonia. Of the 24 water samples tested, 8 (33.3%) grew the same organism.
A 53 years old British tourist had come to India in November 2003, and had visited Delhi, Agra, Jaipur, and Goa. He went back to the United Kingdom on 5 Dec 2003 and died 2 days later.
According to the British High Commission, the person died of Legionnaire’s disease
Thank You
Thank You
Why it Took so Long to Find the Bacillus
It was no ordinary microbe. It could not be grown under typical conditions, being dependent upon ridiculous demands: high levels of the amino acid cysteine and inorganic iron supplements, low sodium concentrations, as well as activated charcoal to absorb free radicals. In addition, it preferred elevated temperatures, which was highly abnormal among pathogens, who preferred near-body temperatures.
It did not help that the team of CDC researchers had been using the wrong animal model at the start, and had only gotten results when they switched from mice to guinea pigs
where exactly was this bacteria from, and how did it come to infect the World War II
veterans?
Dr Carl Fliermans solved the first part of the puzzle when he discovered that L pneumophila lipids resembled those of the thermophilic bacteria he'd found in the thermal regions of the Yellowstone National Park, and that this bacteria tended to live as biofilm (scum) associated with certain species of algae. Subsequently, Fliermans began poking around aquatic habitats and found - guess what? - this bacteria residing in thermal waters discharged from a nuclear reactor at Savannah River Laboratory.
This bacteria was later found to be living in natural hot springs all over the United States and, most importantly, in air-conditioning cooling towers.