Legionnaire’s Disease HPA Surveillance & Outbreak Management
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Transcript of Legionnaire’s Disease HPA Surveillance & Outbreak Management
Legionnaire’s Disease
HPA Surveillance & Outbreak Management
Rebecca Ingham
Health Protection Practitioner
West Yorkshire Health Protection Unit
The West Yorkshire HPU
West Yorkshire HPU:
5 CCDC’s (Consultant in Communicable Disease Control):
All CCDC’s are Dr’s in our Unit
Patch work – 1 CCDC to each patch
Duty CCDC - on daily basis
9 Health Protection Specialists:
8 HP Nurses + 1 HP Practitioner
Patch work – 2 HPS to each patch
Duty Professional – approx 1 or 2 days/ week
Surveillance team
PA support/ Administration Team
Trainees
Specialist Registrars (medic trained) & Specialist Trainees (non medic)/ FY2’s – Junior Dr’s
Legionella pneumophilia
• Ubiquitous: Aquatic: lakes and streams
• 46 species including L. pneumophilia (serogroup 1 causes most LD)
• Spread through aerosols
• Cooling towers, spas, shower heads, taps, humidifiers
• No person-to-person transmission
Clinical features
• Legionnaires’ disease: Incubation Period 2-10 days
Non specific flu like illness: fever, malaise, myalgia, headache, dry cough, anorexia often with diarrhoea and confusion
• Difficult to differentiate clinically from other atypical pneumonias
• Become ill quickly
• Complications:
resp failure, pericarditis, acute renal failure
• Treatment:
Erythromycin
• 5-15% mortality
• Pontiac fever: self limiting, Incubation Period 5-66hrs
Microbiological Investigation
• Culture: need special media
• Antibody detection: takes 3-6 weeks to rise to diagnostic levels
• Serogroup 1 urinary antigen: early diagnosis – fast and dirty testing of urine
• Usual to also get sputum or other respiratory samples (bronchial washings) for testing
• Genotyping available to support epidemiological investigations
i.e. human and env samples ‘fingerprint’ the same
• Environmental sampling to investigate suspected sources. Routine sampling not worthwhile
Epidemiology
• Incidence ?? Over 200 cases a year in the UK
• 70% in Males
• 90% in the over 30’s
• Travel associated accounts for about 50% of cases
Spain, Turkey, France, Italy, Greece
• 15% associated with outbreaks
• 2% hospital acquired
• Risk factors:
Age, smoking, lung and kidney disease, immunosuppression, alcohol
• Incidence appears to be rising, probably due to better awareness and testing
Year Total Cases Male CasesFemale Cases Deaths
Travel Associated
(Abroad & UK)
1997 226 165 61 28 114
1998 227 162 65 25 115
1999 200 150 50 28 91
2000 180 143 37 25 101
2001 182 142 40 26 100
2002 387 256 131 33 154
2003 314 238 76 35 174
2004 318 239 79 38 173
2005 355 271 83 30 179
2006 551 433 118 53 213
2007 442 328 114 53 199
2008# 359 281 78 34 152
Legionella cases Eng and Wales
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Month
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of C
ases
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2008#
Surveillance: Why?
• See trends: descriptive epidemiology, at risk populations – age, travel
• Detect outbreaks
• New infections: seasonal flu virus, pandemic virus
• Implement interventions to prevent spread of disease
• Monitor effectiveness of interventions
Dissemination of Surveillance Data
• Health Protection Report and HPA website
• European Legionnaires’ disease Surveillance Network (ELDSNet )
• European Centre for Disease Prevention and Control (ECDC)
• World Health Organisation (WHO)
Investigation of a Case
• Confirm case: Test validated at CfI
• Notifiable in Eng&Wales (since 2010)
• Risk factor history for previous 2 weeks
– Travel, place of work, hospital acquired?
• Other cases? (diagnosed, undiagnosed?)
• Inform LA H&S and HSE
• LA holds a database of cooling towers (is it up to date?) Check out sampling records
Surveillance Data Set:
• Patients demographics:
Age/ DoB/ Gender/ Home & Work Address/ Occupation
• Clinical History:
Onset/ Relevant med history/ Hospital admission/ Outcome
• Exposure history:
? hospital acquired
Community acquired (known exposure to cooling towers, whirlpool spas, showers)
Travel associated Country (s) visited, dates of stay, name & address of accommodation, room number, tour operator, use
of showers, spa pools
Household acquired - Use of household water system during incubation period, in absence of other exposures
Clusters, Outbreaks & Travel Associated Clusters
• Cluster
• Outbreak
• Travel Associated Cluster
Strength of evidence for outbreaks
• High
• Low
Outbreaks
• Active case finding
• Detailed analysis of movements
• Mapping
• Identify potential sources: inspections and detailed look at records
• Hospital acquired: check all sources
• Engineer’s advice
• Typing results
Legionella
Prevention and Control
• Health and Safety
– Employers should identify, assess and manage risks
– Cooling towers notified and maintained
– Testing and addition of biocides to limit growth
• Reporting of cases: locally and nationally
• Investigation of cases
• Increasing awareness
– Professionals: thinks of Legionella and if you find it report it
– Employers aware of risks and duties
– Public beware of the risks
Managing Outbreaks Requires All of us Working Together
How to reach us:
West Yorkshire HPU
6th floor South EastQuarry HouseQuarry HillLEEDS LS2 7UE
Telephone:
0113 386 0300
Duty desk: option 1
Email:
1st April 2013:
NB soon to be Public Health England
HPA website:
www.hpa.org.uk
1st April 2013
www.phe.gov.uk