Legionnella You can t t see it but you can catch it Dr Charmaine Gauci MD, MSc, PhD Head of Disease Surveillance Unit
Legionella infections First documented outbreak name from 221 cases of pneumonia occurred amongst 4,000 delegates attending the 58th American Legion convention in Philadelphia in July 1976 Bellevue Stratford Hotel, Philadelphia 15% fatality rate (34 died) was intensely investigated.
Vendetta waged against Legionnaires America s s finest fighting men Five months later: BUG was identified Other previous outbreaks explained- earliest documented 1947
The Bug
Gram negative bacillus Legionella pneumophila
Legionella pneumophila Gram negative bacteria Invisible to the naked eye 1-22 micrometer long 0,5 micrometer wide Found naturally in environmental waters Rivers, lakes Reservoirs
Legionella pneumophila Can get into water systems Airconditioning systems Hot tubs, Whirpools,, spas Hot/ Cold water tanks Showers
Legionella pneumophila Proliferate Temperatures around 20-45 degrees Celsius Stagnant water
Transmission Breathing of aerosols (mists) that come from a water source contaminated with Legionella bacteria No transmission via drinking water No documented person to person transmission
Legionnaires disease Bacteria enter lungs by inhalation of aerosols of contaminated water Cause pneumonia
Susceptibility Middle-aged and older persons smokers diabetes mellitus chronic lung disease renal disease malignancy Immunosuppressed (kidney failure, cancer, AIDS)
Clinical symptoms Incubation period: 2-102 days up to 18 days Bacteria grow in lung Pneumonia Spread via blood or lymph system Extrapulmonary manifestations
Clinical symptoms fever, malaise, myalgia,, headache and often diarrhoea high fever and non productive cough which becomes productive chest signs non impressive. case fatality rate is high- 15%.
Chest X-RayX
Chest X-RayX
Diagnosis Clinical picture High index of suspicion Chest X-RayX Urinary antigen testing Culture of organism from secretions Serological testing
Outcomes Serious disease Can be fatal Up to 10% of cases In Malta : 2003 1 death 2004 2 deaths
Treatment Antibiotics (Erythromycin/ Rifampicin) Respiratory Supportive care
Frequency and Distribution About 200-300 cases occur in the UK each year mostly sporadic or small groups 8,000-18,000 occur in US each year
Outbreaks Outbreaks do occur Hotels Institutions Hospitals Community
Outbreaks Associated with: Hot and cold water systems- e.g. taking showers Cooling towers Whirlpool spas Fountains
Investigating outbreaks Patients with legionnaires disease Place of residence Whereabouts of patients Activities in the previous days Travel Investigating suspected water sources Testing water sources
Netherlands Community OB Large increase in number of cases in 1999 Environmental investigation Case control epidemiological analysis Serologic cohort study Associated with flower show Of 77,061 visitors, 188 became ill Positive for legionella bacteria 2 whirlpool spas of exhibits Sprinkler in a hall Control Actions
Muricia Community OB On 7 th July 2001 start of an epidemic 470 cases identified Of these one died
Epidemiological investigation 75% lived in Northern Region of city Case Control Study Environmental Investigation Positive cooling towers of city hospital
Australia Community OB April 2000 101 cases of legionnaires Aged 23-89 years 2 deaths Had visited Melbourne Aquarium Confirmed Legionella bacteria in cooling towers Disinfection
OB in Hotel Sweden February 2005 Luxury hotel and spa in centre of Sweden 50 guests with Pontiac fever Fever, chills, fatigue, muscle aches, headache Suspected 2 whirpools Swimming pool
OB in Oklahoma Hotel March 2004 National basketball tournament for children and family members Staying in hotel in Oklahoma 65 cases with Pontiac fever Suspected Hotel pool and hot tub
OB in Hospital, Barcelona Hospital Lasts i Reynals February 2005 9 cases, 1 death Immunodeficient patients (on cancer treatment) Nosocomial origin Problem in internal circuit of water Infection propagated through cloud of gotitas that leave showers and water faucets Hyperchlorination and disinfection
Hotel in Turkey 55 year old notified Sept 28th 2004 Ten more guests in early October Staying in hotel in Turkey Hotel closed down
Disease Surveillance Unit Department of Public Health
Legionnaires disease Malta 1989-2004
Underestimate Many go unreported We may have more cases Not reported Not diagnosed
EWGLI European Working Group for Legionnella Infections EU Working group Aim to link cases of legionelloses European Guidelines for Control and Prevention of Travel Associated Legionnaire s s Disease http://www.ewgli.org
Outbreak in Malta 2003 One case reported from EWGLI in September 2003 Inspection done Another case diagnosed in Malta in October Inspection & Sampling risk assessment and treatment recommended Two other cases diagnosed in Malta in November Closure of hotel for further control measures
Outbreak in Malta 2004 One case reported from EWGLI 24 th Sept 2004 Inspection Another three cases from EWGLI 8 th, 11 th 12 th October Closure of hotel for control actions th,
Constant vigilance Active Surveillance Awareness General public Health Professionals Personnel in hotels, institutions Information Web site of DSU: http://www.health.gov.mt/dsu Code of practice Lectures, seminars Legislation
Prevention is better than cure